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Title: A Treatise on the Plague and Yellow Fever: With an Appendix, containing histories of the plague at Athens in the time of the Peloponnesian War; at Constantinople in the time of Justinian; at London in 1665; at Marseilles in 1720
Author: Tytler, James
Language: English
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*** Start of this LibraryBlog Digital Book "A Treatise on the Plague and Yellow Fever: With an Appendix, containing histories of the plague at Athens in the time of the Peloponnesian War; at Constantinople in the time of Justinian; at London in 1665; at Marseilles in 1720" ***

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YELLOW FEVER ***

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                                    A

                                TREATISE

                                 ON THE

                                 PLAGUE

                                   AND

                              YELLOW FEVER.

                     _With an APPENDIX, containing_

           HISTORIES OF THE PLAGUE AT ATHENS IN THE TIME OF
              THE PELOPONNESIAN WAR; AT CONSTANTINOPLE IN
               THE TIME OF JUSTINIAN; AT LONDON IN 1665;
                      AT MARSEILLES IN 1720; &c.

                            By JAMES TYTLER,
      Compiler of the Medical Part of the Encyclopædia Britannica.

   Let every one, Physician or not, freely declare his own sentiments
    about it; let him assign any credible account of its rise, or the
 causes strong enough, in his opinion, to introduce so terrible a scene.

                                                          THUCYDIDES.

                       ‘Twas all the business then
              To tend the sick, and in their turns to die,
                           In heaps they fell.

                                                           ARMSTRONG.

                _Published according to Act of Congress._

                                _SALEM_:

                     PRINTED BY JOSHUA CUSHING, FOR
                            B. B. MACANULTY.

                                  1799.



CONTENTS.


  PART FIRST.

  _Of the_ Asiatic _or_ True _Plague_.


  SECTION I.                                                        Page

  _Of the Plague in general.--Inquiry into the Antiquity of the
  Distemper.--Of the Plagues mentioned in the Old Testament.--
  History of several remarkable Plagues which, at various times,
  have desolated the world._                                           1


  SECTION II.

  _Of the Countries where the Plague is supposed to originate.--
  The Influence of Climate in producing Diseases.--And of the Moral
  Conduct of the Human Race in producing and influencing the same._   21


  SECTION III.

  _Of Disease in general.--The nature of the Plague as a Disease
  considered.--Of Contagion.--Whether the Plague is Contagious or
  not.--Medical History of the Distemper.--Inquiry into its
  Immediate Causes, and whether an approaching Plague is indicated
  by any visible Signs._                                              74


  SECTION IV.

  _Of the best Methods of Preventing the Plague._                    302


  SECTION V.

  _Of the Cure of the Plague._                                       347


  PART SECOND.

  _Of the Yellow Fever._


  SECTION I.

  _History of the Yellow Fever._                                     371


  SECTION II.

  _Symptoms of the Yellow Fever, as described by various authors.
  --Comparison between them and those of the Plague, with an
  inquiry into the Causes.--History of the Distemper as it has
  appeared in various parts of the United States since the year
  1793.--A discussion of the question Whether the Yellow Fever
  is Contagious or not._                                             382


  SECTION III.

  _Methods of Prevention and Cure._                                  507


  SECTION IV.

  _Remarkable Cases._                                                534


  _APPENDIX._

  N^o I.

  _Account of the Plague at Athens, in the time of the
  Peloponnesian War:--From_ THUCYDIDES,--SMITH_’s Translation_.      545


  N^o II.

  _Account of the Great Plague in the time of_ JUSTINIAN:--_By_
  PROCOPIUS.                                                         547


  N^o III.

  _Account of the Plague at London in 1665:--From Dr._HODGES _and
  others_.                                                           548


  N^o IV.

  _Account of the Plague at Marseilles in 1720:--From the
  Periodical Publications of the time._                              554


  N^o V.

  _Account of the Plague in Syria, Cyprus &c.--From Dr._PATRICK
  RUSSEL_’s Treatise_.                                             ibid.


  N^o VI.

  _Remarkable case of a Remitting Fever at Bassorah in 1780._        556


  N^o VII.

  _Set of Queries furnished by Doctors_ AIKIN _and_ JEBB; _and by
  Mr._ HOWARD _put to several foreign Physicians, during his tour;
  with their Opinions concerning the Plague_.                        563



A

TREATISE

ON THE

Plague and Yellow Fever.



PART FIRST.

_Of the_ Asiatic _or_ True _Plague_.



SECTION I.

  _Of the Plague in general.--Inquiry into the Antiquity of the
  Distemper.--Of the Plagues mentioned in the Old Testament.--History
  of several remarkable Plagues which, at various times, have desolated
  the world._


Among the many diseases which afflict the human race, we find ONE,
upon record, so irresistible in its progress, so fatal in its attacks,
and so entirely beyond the powers of medicine; that, like the serpent
_Python_, the _Leviathan_, or the _Mammoth_, among animals, it has
generally been distinguished by names expressive of its destroying
nature; not, like other diseases, by any particular appellation derived
from its symptoms. In the Hebrew language this distemper is expressed
by the word which signifies _perdition_;[1] in Greek it is called
_loimos_, from _luo_, to destroy; in Latin, _pestis_, from _pessundo_,
to overthrow; and in English, the _plague_, from the Latin _plaga_,
a stroke with a whip; alluding to the common opinion, that it is a
scourge from heaven, taking vengeance on mankind for their sins.

  [1] Thus Dr. Hodges; but Calmet informs us, that the Hebrews call
  by the name of plagues all diseases sent by way of punishment or
  correction from God; as the pestilence, infection, the leprosy,
  sudden deaths, famines, tempests: in a word, all calamities, whether
  public or private. _Calmet’s Dict._ vol. ii. fol. 412. _Plaga._

  Parkhurst derives the Greek term _loimos_, either from _luo_, as
  above, or from another Greek word signifying _to faint_; the same
  from which the English word _eclipse_ has its origin; or it may be
  from the Hebrew _lehem_, to consume.

  A friend observes, that “we no where find the word _perdition_
  in our version of the Old Testament. We have, however, the word
  _destruction_, which is of a similar import; as, for instance, in
  Prov. xv. 11. where the Hebrew is _abdun_. In Rev. xvii. 8 & 11, we
  find the English word _perdition_; but as we have no Hebrew version
  of the New Testament, we may advert to the ancient Syriac version.
  The Syriac being a sister dialect of the Hebrew, differs, radically,
  but little from it. The Syriac of the two places referred to above is
  _abdna_; hence the word _abaddon_, whole root is _abd_, and is the
  same with that of the Hebrew word above.

  “As to the word _plague_, we often find it in the Old Testament, but
  perhaps never in that specific sense in which the moderns use it. The
  original word, rendered plague, is pretty generally _ngp_, or its
  derivations; as Exod. xii. 13., ii. Sam. xxiv. 21, &c.” On this last
  occasion, however, as the word _pestilence_ had been used before, in
  the same chapter, we can scarce doubt its having been really some
  kind of disease: and we know that modern plagues will sometimes
  destroy as quickly as this is said to have done.

Other distempers, called by the general name of _Epidemics_, have at
different times infected whole cities, and even overspread extensive
regions; but these, though sometimes very fatal, have always been
found so much inferior to the distemper of which we treat, that, on
a comparison, we may justly say, though epidemics have slain their
_thousands_, the true plague has slain its _ten thousands_. In speaking
of the destructive ravages of epidemics, we may count the dead by
tens, by hundreds, or by thousands; but in the true plague, always by
thousands, by myriads,[2] or by millions. Procopius, when speaking of
a plague which desolated the world in his time, compares the number
of the dead to the sand of the sea; and Mr. Gibbon, who attempts to
specify, thinks they might amount to an hundred millions;[3] and I
cannot help being of opinion, that the destruction generally occasioned
by violent plagues, amounts to about one half of the population; the
reasons for which opinion will be given in the course of this work. In
all violent plagues, we hear of the dead being left unburied; of their
being cast into pits, &c. But if we wish to make any gross comparison
between the destructive power of the true plague, and that of any other
violent epidemic, we cannot, perhaps, have a better instance than
that which took place at Bassorah (a city on the confines of Persia)
in the years 1773 and 1780.[4] In the former of these years that city
was visited by the true plague; and in the latter, by an epidemic
remittent fever. The fever was most violent in its kind, and destroyed
twenty-five thousand in the city and neighbourhood; but the true
plague, no fewer than two hundred and seventy-five thousand in the same
place. Supposing the two computations therefore to be equally exact, we
must calculate this plague to have been eleven times more deadly than
the epidemic. If therefore the ingenious classifiers, in modern times,
have brought into alliance the plague with other epidemic diseases,
and characterised the former from the latter; we may justly say, that
they have fallen into the same error with other naturalists, who
characterise the superior from the inferior; the lion from the cat, not
the cat from the lion. As to the remedies applied in these diseases,
doubtful in epidemics, they so universally fail in the true plague,
that, notwithstanding the improved state of medicine, we may yet say,
it stands among diseases, in a great measure, like a giant without any
champion to oppose; like a poison without any antidote.

  [2] A myriad is generally supposed to contain ten thousand.

  [3] Gibbon’s History, vol. iv.

  [4] Transact. of Society for improving Medical Knowledge.

In this unhappy predicament, the breaking out of a plague, in any city
or country, proves a most distressing calamity, not only on account of
the numbers destroyed by the disease itself, but by reason of the bonds
of society being loosed; so that humanity gives way to terror; children
are abandoned by their parents, and parents by their children; every
thing wears the appearance of ruin and desolation; while, in too many
instances, avarice urges on the unprincipled to rapine, or even to
murder. Nor are the cruel modes of prevention, sometimes practiced even
by the authority of the magistrate, less abhorrent to humanity, then
the lawless outrages of the thief or murderer. Instances of all this
will appear in the course of the work; the following are so remarkable,
that I cannot help inserting them in this place. In the great plague at
Marseilles, in 1720, the town being almost deserted, and few choosing
to venture into it, “three sea-captains, and some hundreds of sailors,
having the courage to enter the city, from the sea-side, found therein
a gang of murderers, who made it their business to destroy people
seized with the plague, and to plunder their houses. The ringleader of
them, named _Rouanne_, a gunsmith, was broken alive upon the wheel, and
forty others were hanged. Rouanne owned that he had killed a thousand
persons. There were found, upon one of the murderers, jewels to the
value of more than thirty thousand livres.”[5] During the time of
this public calamity, four men, who came from Marseilles to Aix, were
shot by order of the parliament, lest they should have brought the
infection along with them.[6] Even this is not equal to what Mr. Howard
informs us was practiced in a hamlet of Dalmatia, where, the plague
having raged with such violence, that only two or three remained; the
neighbouring magistrates ordered these miserable survivors to be shot.
At such prices will people buy a precarious, nay, an imaginary, safety.
In short, what Mr. Gibbon says of the situation of people in the time
of violent earthquakes, will also, in a great measure, hold good in
the time of pestilence, or any great public calamity. “Instead of the
mutual sympathy which might comfort and assist the distressed, they
dreadfully experience the vices and passions which are released from
a fear of punishment; the houses are pillaged by intrepid avarice,
revenge embraces the moment and selects the victim: while [7]vengeance
frequently overtakes the assassin or ravisher in the consummation of
his crimes.”

  [5] Political State for 1720.

  [6] Political state, ibid.

  [7] Mr. Gibbon, agreeably to the subject on which he writes,
  particularises the mode of vengeance; saying, “the _earth frequently
  swallows up_ the assassin,” &c. It is hoped the substitution of
  the word _vengeance_, in general, will not be deemed a material
  alteration.

Whether the world hath been in the same predicament ever since the
human race began to multiply, or whether plagues have originated at
some remote period, is a question not easily determined. It is certain
that, as far as histories go, they give us accounts of plagues;
much less frequent indeed in very ancient times than in those which
followed; but the compass of historical knowledge is narrow. There are
no authentic histories of any nation previous to the termination of
those of the Old Testament. Where sacred history ends, profane history
begins. The fabulous period affords many accounts of wars, heroes,
giants, and monsters, but scarce any of plagues. Diodorus Siculus
indeed makes mention of a plague which happened in Greece, after the
flood of Deucalion; and which, he says, was occasioned by the general
corruption of vegetables, &c. consequent on the flood. Deucalion’s
flood is supposed to have been nearly cotemporary with the departure
of the Israelites from Egypt; so that, if there is any truth in the
relation of Diodorus, it is not improbable that some of the Egyptian
plagues might have spread into Greece. We are likewise told of a
pestilence at Athens in the time of Theseus;[8] but all the accounts
of these times are so uncertain, and so much involved in fable, that
little or no dependence can be placed on any of them.

  [8] Univ. Hist. vol. vi.

The first distinct account we have of plagues of any kind, then, is in
the book of Exodus, where we are told of many heavy judgments sent upon
the Egyptians because of their disobedience. Before this, indeed, we
read of plagues sent on the king of Egypt, for having taken Abraham’s
wife; but as these fell only upon the king and his household, we cannot
suppose any thing like a general pestilence to have taken place among
the people. In like manner did it happen to Abimelech, king of Gerar,
on the same account. All the women belonging to the king’s household
were rendered barren for a time; but we hear of nothing happening
to the nation at large. Again, when Moses and Aaron went in before
Pharaoh, they said to him, “Let us go and sacrifice to the Lord our
God; lest he fall upon us with the sword, or with _pestilence_.” This
shews indeed that both Moses and Pharaoh knew that such a thing as
_pestilence_ existed, or might exist; but it cannot prove that the
disease we now call the plague or pestilence commonly took place among
nations in those days as it has done since. Even among the plagues
inflicted upon the Egyptians by the hand of Moses and Aaron, we find
only two that can be supposed to have any similarity to the disease we
now call the _plague_; viz. the _boil_, and the destruction of their
first born. The former _may_ have been pestilential buboes; the latter
also _may_ have been the effect of a most malignant pestilence; such
as, in the beginning of it, is said frequently to kill suddenly, as by
lightning; but whether it was so or not, we cannot now determine.

In the history of Job, who is supposed to have been cotemporary with
Moses, we have a case more in point. The boils, with which he was
covered, are by Dr. Mead supposed to have been the small pox; though in
the true plague the body is sometimes covered with gangrenous pustules,
constituting a disease still more dangerous and painful than the small
pox; but whatever the disease of Job was, we may reasonably conclude,
that in his time there was none similar to it commonly existing among
mankind.

After the departure of the Israelites from Egypt, we find frequent
mention of a plague as a disease commonly to be met with; but it was
always that of leprosy; those destructive plagues, which might be
supposed to resemble the disease we now call by that name, being all
miraculous. Concerning the prevalence of the leprosy among the Jews,
Diodorus says that they “were driven out of Egypt as impious, and
hateful to the gods; for their bodies being overspread and infected
with the itch and leprosy, (by way of expiation) they got them
together, and, as profane and wicked wretches, expelled them out
of their coasts.” This he tells us was a reason given to one of the
kings of Syria why he should exterminate the Jews. In another place
our author gives the following account of the origin of the Jewish
nation. “In ancient times there happened a great plague in Egypt, and
many ascribed the cause of it to God, who was offended with them. For
there being multitudes of strangers of several nations who inhabited
there, who used foreign ceremonies, the ancient manner of worship was
quite lost and forgotten. Hence the natural inhabitants concluded,
that unless the strangers were driven out, they should never be freed
from their miseries. Upon which they were all expelled,” &c. He then
tells us that some of them came into Greece under the conduct of Danaus
and Cadmus; but the greater part entered Judea, then quite desert and
uninhabited. Their leader “was one _Moses_, a very wise and valiant
man,” &c.[9]

  [9] Diodor. Sic. Frag.

The allusion, in this last passage of Diodorus, to the plagues of
Egypt, mentioned in Exodus, is manifest; and it is equally manifest,
that the Egyptians themselves, as well as the sacred historian, owned
them to be miraculous. Here, however, let it be remarked, that, though
these, and others inflicted on the Israelites, were miraculous, we
are not from thence to conclude that they took place without the
intervention of natural causes. On the contrary, in speaking of the
plagues of Egypt, we are told, that when the locusts came, “the Lord
sent a strong _east wind_, all that day and all that night; and when
it was morning, the _east wind_ brought the locusts.” In like manner
“the Lord turned a mighty strong _west wind_, which took away the
locusts, and cast them into the Red sea.” Again, when the sea itself
was divided, “the Lord caused it to go back by a strong _east wind_ all
that night.” The Egyptians were witnesses to this; but, as they did not
believe that the powers of nature had any superior, they could never be
induced to think that any of the elements would take part in a dispute
between two nations, or favour the one more than the other.

In diseases inflicted on the human body, we are assured that the powers
of nature were as much employed as in the miracles already mentioned.
When it was told David that the child born to him by Bathsheba should
die, the infant was seized with a natural distemper, probably a fever,
and died the seventh day. When Hezekiah was informed that he should
die, he did not, any more than David had done, give himself up to
despair; but used, for his recovery, such means as were in his power,
viz. prayers to God; from whom, by the constitution of things under the
Old Testament, he would receive a direct answer. And it is remarkable,
that though the answer was favourable, yet the disease was not removed
by any invisible power operating like a charm, but by the use of a
remedy. It is plain therefore that this disease was occasioned by one
natural power, and removed by another. The boil (for that was the
distemper) was brought to maturity by a poultice of figs, and the king
recovered.[10] If then the scripture informs us, that even where the
Deity himself speaks, he has directed the use of a remedy, much more
ought we to be diligent in the use of such as our feeble skill can
suggest, in those cases where he leaves us entirely to the exercise
of our own judgments. To sit down supinely, in case of a dangerous
distemper, with a notion, that if God wills us to die we certainly
shall die, _in any use of natural means_; and if he wills the contrary,
that we shall as certainly recover, _in any neglect of them_; is a
conduct equally unscriptural and absurd.

  [10] Mead.

In the books of Moses we find the Israelites, in case of disobedience,
threatened with the _botch_ of Egypt; with terror, consumption, and the
_burning ague_. From the name of this last we may reasonably suppose
it to have been the same with the remitting fever of the East, which
is attended with the most intolerable sensation of burning in the
bowels; but whatever the nature of these diseases might have been,
they certainly were not very common in the world at that time, or they
would not have been threatened as extraordinary judgments. They were
not the same with the pestilence; because we find, that after they
had been threatened with fever, consumption, and extreme burning, it
is added, “I will make the _pestilence_ cleave unto thee:” as if it
had been said, that the pestilence, which hitherto had appeared only
on extraordinary occasions, should then become _endemic_, and never
leave them. But, on the whole, the first account we have of any general
plague, seems to be that which was inflicted on the Jews on account
of the sin of their king in numbering the people. David was nearly
cotemporary with the Trojan war; and Homer, in the first book of his
Iliad, informs us, that a plague likewise took place in the camp of
the Greeks; and that too for the sin of their king in carrying off the
daughter of the priest of Apollo, and refusing to restore her at the
entreaty of her father.

In comparing the account of the sacred historian with that given by
Homer, we cannot help observing a striking similarity between them.
Both plagues were inflicted on the people for the sin of their kings;
both were miraculous; the one continued three days, the other nine.
In both the Deity himself appeared: an angel brandished a drawn sword
over Jerusalem; and Homer says, that, from the top of Olympus, Apollo
shot his arrows into the Grecian camp. Lastly, both were stopped in a
similar manner: David offered sacrifices to the true God; and Agamemnon
returned Chryseis, his captive, to her father, the priest of Apollo,
by whose prayers and sacrifices the plague was stopped. Hence it seems
not impossible, that the story told by Homer, is only that of David,
altered as he thought most proper for embellishing his poem; and that
this was the first remarkable plague in the world.

In the year 767 B. C. we hear of a universal pestilence; but the
imperfect state of history in those early periods affords few accounts
that can be depended upon, either concerning that or any thing
else.[11] Till after the foundation of Rome, indeed, authentic history
scarce commences; and it is not till the 279th year of that city,
that we hear of its being in any remarkable degree infected with a
pestilential disorder.[12] The plague we speak of is said to have taken
place about the year 469 B. C. which comes within 38 years of that of
Athens in the time of the Peloponnesian war. The near coincidence of
these dates, in times so remote, and when chronology was so little
settled, tends to excite a suspicion that both arose from the same
infection. Of its ravages at Athens we have an excellent account
by the historian Thucydides,[13] who was an eye witness of what he
writes. He says, that according to report it began in Ethiopia, from
whence it came down into Egypt, and thence into other countries. It is
possible, therefore, that it might reach Italy some time before it came
into Greece; for it seems scarce probable, that such a very violent
infection could have taken place in Italy without being communicated to
the neighbouring countries; whence we may reasonably conclude, that the
first plague at Rome, and that of Thucydides, were the same. At Rome,
we are informed, it swept away almost all the flower of the youth who
were able to bear arms, the greatest part of the tribunes, and both the
consuls. The mortality was so great, that no place of sepulture could
be found for the dead bodies, but they were thrown promiscuously into
the Tiber. In short, so low were the Romans at this time reduced, that
the Æqui and Volsci, two Italian nations with whom they were almost
always at war, made an immediate attack, in hopes of being easily able
to carry the city; but in this they were disappointed. The situation
of Athens was truly deplorable; being not only engaged in a foreign
war, but crowded with people from the country; numbers dying daily in
the streets, and the survivors giving themselves up to all manner of
licentiousness.[14]

  [11] In the subsequent section this plague will be more fully treated
  of.

  [12] A plague is spoken of in the time of Romulus; but the accounts
  of this, and some others, are extremely obscure and indistinct.

  [13] See Appendix No. I.

  [14] See Thucydides’s account at large, Appendix No. I.

As it seems probable that the same infection desolated both Rome and
Athens, so it seems not unlikely that it was a continuance of the same
which destroyed the Carthaginian army in Sicily, while carrying on a
successful war against Dionysius, tyrant of Syracuse. The plague, as we
are informed by the Universal History, was common in the Carthaginian
territories, especially those on the continent of Africa; and this
pestilence broke out soon after the conclusion of the Peloponnesian
war. As it originally came from Africa, it is probable that it had
never been quite extinguished there; and the compilers of the Universal
History think it probable that the army might have brought the seeds
of it along with them into Sicily. But, whatever was the origin, the
distemper soon became so malignant, that the living were not sufficient
to bury the dead; and those who attended the sick perished in such a
manner, that, after some time, few dared to come near them. At first
they gave the dead a kind of burial; but in time the number became
so great, and the survivors so few and weak, that an hundred and
fifty thousand are said to have rotted above ground. “Justin seems
to intimate that almost the whole Carthaginian army perished by the
plague; and that in a manner all at once, as it were in an instant.
Diodorus, however, informs us, that a considerable body of Africans
and Iberians survived the dreadful calamity. It is worth observation,
that not a single person of those who attended the sick survived.” The
miserable remains of this army, consisting at first of more than three
hundred thousand, were now attacked by their enemies, whom they were no
longer able to resist. Their land forces were entirely defeated, and
their fleet was burnt: “the Gods themselves, (says Diodorus) when the
ships were all in a blaze, and the flames ascending above the masts,
seeming to destroy the Carthaginians with lightning from heaven.” Forty
gallies still remained, and the unfortunate general was now obliged to
purchase liberty to return with the few men he had left. But even these
were treacherously attacked by the tyrant’s fleet, and several of them
sunk. On his arrival at Carthage, he found the whole city not only in
mourning, but in despair: “the wretched inhabitants giving full vent to
their grief, made the shore ring with their groans and lamentations.
In short, a greater scene of horror, except the spot of ground where
the Carthaginian army encamped before Syracuse, than Carthage now was,
cannot well be conceived.” This reception completed the despair of
the unhappy general. Clothing himself in mean and sordid attire, he
joined with the rest in bewailing their common calamities. After some
desperate exclamations against the gods, whom he accused of partiality,
“The enemy, said he, may rejoice at our misery, but have no reason to
glory in it. The troops we have lost did not fall by their valour, nor
did they now oblige those that arrived here to leave Sicily by force.
We return victorious over the Syracusians, and are only defeated by
the plague. As for the baggage found in our camp, this ought not to be
looked upon as the spoils of a conquered enemy, but as moveables which
the casual death of their owners has left the Syracusians in possession
of.” Having then gone on to express his grief for the loss of his army,
and declared his intention not to outlive them, he shut himself up in
his house, refusing admittance even to his own children, and put an end
to his life.[15]

  [15] Univ. Hist. vol. xvii.

Whether the unfortunate remains of this army brought with them the
infection to Carthage, and there produced a new scene of desolation, we
are not informed; but there seems to have been a very great tendency
to pestilential disorders in the Carthaginian armies; for, in the time
of the siege of Syracuse by Marcellus, a plague broke out in the camp
of the Carthaginians who had come to assist the Syracusians. From them
it passed into the city itself, with so much malignity, that nothing
was to be seen but heaps of dead and dying. None durst receive or
assist the sick, for fear of being infected by them; and the bodies
of the dead were, for the same reason, left unburied, to infect and
poison the air with their putridity and corruption. Nothing was heard,
night and day, but groans of dying men; and the heaps of dead bodies
continually presented mournful objects to the living, who expected
every moment the same fate.[16] The infection reached the Roman camp;
but we do not hear of its being conveyed, at this time, either to
Rome or Carthage. In the time of the contest with Jugurtha, however,
a very terrible calamity took place in Africa. “According to Orosius,
a great part of Africa was covered with locusts, which destroyed all
the produce of the earth, and even devoured dry wood. But, at last,
they were all carried by the wind into the sea, out of which being
thrown in vast heaps upon the shore, a plague ensued, which swept
away an infinite number of animals of all kinds. In Numidia only,
perished eight hundred thousand men; and in Africa Propria, two hundred
thousand; among the rest, thirty thousand Roman soldiers, quartered
in and about Utica for the defence of the last mentioned province. At
Utica, in particular, the plague raged with such violence, that fifteen
hundred dead bodies were carried out of one gate in a day.”[17]

  [16] Univ. Hist. vol. viii.

  [17] Id. vol. xviii.

From the time that the Romans finished their African wars, till they
had accomplished most of their conquests in Asia, their empire seems
to have continued free from this dreadful scourge; but soon after the
destruction of Jerusalem by Titus, such a violent infection seized on
the city, that for some time upwards of twenty thousand are said to
have died in it daily.

As the Roman arms were carried still farther to the eastward, and all
the countries reduced, to the confines of Persia, the plague seems to
have become more common among them. In the time of Marcus Aurelius, a
war was undertaken against the Parthians, which was carried on by the
Romans with great success, and with no less cruelty; for, though the
city of Seleucia opened its gates to the Roman general, he caused the
inhabitants, to the number of four hundred thousand, to be massacred.
But they soon paid dear for this cruelty, by a dreadful pestilence,
which broke out, according to the historian Ammianus Marcellinus, in
the very city which they had desolated, and was brought by their army
into Italy, from whence it spread throughout the whole empire. Other
historians say, that it originated in Ethiopia, from whence it spread
into Egypt, and thence into the country of the Parthians. We know not
how long the infection continued; only that, some years afterwards,
when the emperor was defeated by the Germans, the pestilence still
raged to such a degree, that slaves, gladiators, and even the banditti
of Dalmatia and Dardania, were enlisted for the defence of the empire.
It is certain that great havock must have been made by it, as we find
that the barbarians were encouraged to invade the empire on all sides,
and could scarcely be repulsed; insomuch that historians compare this
with the most destructive wars the Romans had ever waged.[18]

  [18] Univ. Hist. vol. xv.

During the time that the empire was overrun by the northern barbarians,
the plague frequently made its appearance; which we shall have occasion
to notice more particularly in the following section; but in those
times the destruction by the sword was so extraordinary, that less
mention is made by history of any pestilential disorder. In the time of
Justinian, however, about sixty-five years after the final destruction
of the western empire, the most violent plague recorded in history took
place. Of this we have a particular account by Procopius.[19] “The
distemper (says Mr. Gibbon) arose in the neighbourhood of Pelusium,
on the confines of Egypt, between the Sarbonian bog and the eastern
channel of the Nile. From thence, tracing, as it were, a double
path, it spread to the east, over Syria, Persia, and the Indies,
and penetrated to the west, along the coast of Africa, and over the
continent of Europe. In the spring of the second year, Constantinople,
during three or four months, was visited by this pestilence. Such was
the corruption of the air, that the pestilence was not checked, nor
alleviated, by any difference of seasons. The numbers that perished
in this extraordinary mortality have not been recorded; only we find
that, during three months, there died at Constantinople five, and at
last ten thousand a day. Many cities of the east were left vacant, and,
in several districts of Italy, the harvest and vintage withered on the
ground. The triple scourge of war, pestilence and famine afflicted the
subjects of Justinian; and his reign is disgraced by a visible decrease
of the human species, which has never been repaired, in some of the
fairest countries of the globe.”[20]

  [19] See Appendix, No. II.

  [20] Gibbon’s Hist. vol. iv. Procopius, in speaking of the numbers
  who died in this extraordinary plague, compares them to the sand of
  the sea; and afterwards expresses them by a phrase which has been
  translated _two hundred millions_. The phrase is _myriadas myriadon
  myrias_. Mr. Gibbon, by dropping the first word, restricts the sense
  to _one hundred millions_; which he thinks not wholly inadmissible;
  but the probability seems to be, that Procopius did not mean to
  specify the number, but to represent it as incalculable. This is done
  by putting a comma, or semicolon, after the first word; and we may
  then read, that there perished _myriads; a myriad of myriads_. The
  grammar is rectified by reading _myriades_ instead of _myriadae_.

This plague broke out in the time of Justinian, in the year 541 or 542
of the christian era; and not only ravaged Constantinople in the time
of Justinian, but returned with increased violence during the reigns of
many of his successors. In the time of Mauritius we find the Avari, a
barbarous nation to the north of the Danube, driven back by the plague
after they had crossed that river to invade the Roman territories. The
reign of Phocas, successor to Mauritius, was still more unfortunate.
“Great numbers were swept off, either by famine or pestilence; the
earth refused her fruits in season; the winters were so severe, that
the seas were frozen, and the fish destroyed.” Phocas ascended the
imperial throne in 603; but in the midst of such confusion as then
filled the world, we can scarce expect an accurate account of the time
when this most malignant pestilence ceased. We can scarcely suppose
it to have lasted two centuries; but, in the reign of Constantine
Copronymus, which began in 742, we find the distemper still raging, and
the same dreadful phenomena of nature still continuing. The plague, we
are now told, broke out in Calabria in Italy; whence it soon spread
over Greece, Sicily, the islands in the Ægean sea; and at last reached
Constantinople; where it raged for three years together, with such
fury, that the living were scarce sufficient to bury the dead. The
earthquakes, which accompanied or preceded this pestilence, were such
as had never been known in any age. In Syria and Palestine several
cities were swallowed up; others, entirely ruined; and some, if we may
give credit to Nicephorus, removed without any considerable damage, six
miles and upwards from their former seats. At the same time happened an
extraordinary darkness, which lasted from the fourth of August to the
first of October, there being little or no distinction, during all that
time, between day and night.[21] During the reign of the same prince,
there happened such an extraordinary frost, that, at Constantinople,
both seas were frozen for an hundred miles from the shore; the ice
being covered with snow twenty cubits deep, and sufficiently strong
to bear the heaviest carriages. When the frost broke, mountains of
ice and frozen snow, being driven by the wind through the straits,
did a great deal of damage to the walls of Constantinople. The month
following, several prodigies appeared, or were thought to appear, in
the air. At the same time a comet, which the Greeks called _Docites_,
because it resembled a beam, was seen for ten days in the east, from
whence it moved into the west, and shone there for one and twenty days
more. The people were struck with terror and amazement at the sight
of the prodigies, and apprehended the last day to be at hand.[22]
Dreadful earthquakes, strange phenomena in the heavens, inundations,
&c. occurred in the year 812, during the reign of Michael Balbus; but
no remarkable plague is mentioned by the Greek historians, till the
year 1025, when a new train of calamities took place. The plague broke
out in Cappadocia, raging with such violence there, as well as in
Paphlagonia and Armenia, that the people were forced to abandon their
dwellings. A terrible famine followed; after which the earthquakes
again commenced with redoubled fury: at Constantinople they continued
forty days together; while people were terrified by a _comet_ (probably
a large meteor) which passed with a dreadful noise from north to south;
the whole horizon appearing to be in a flame.

  [21] Univ. Hist. vol. xvii.

  [22] Ibid.

From these calamities the world, at least that part of it known to
the Greek historians, appears to have enjoyed some respite till the
year 1346. Indeed we may now say, as in the time of the invasion by
the northern barbarians, that the sword, and not the pestilence, was
the plague of those times. A most violent and universal pestilence,
however, now took place; though, for want of such historians as
Thucydides and Procopius, we cannot here give a particular account of
it. In general we are told, that it began in the kingdom of Cathay (the
northern part of China) from whence it gradually overspread all the
countries between that and the western extremity of Asia. Invading,
at last, Constantinople, it proceeded from thence to Greece, Italy,
France, Africa, Germany, Hungary, Denmark, Britain and Ireland. Thus,
it seems to have been as extensive a contagion as ever appeared in the
world. It is even probable, that, from the remains of this contagion,
Europe hath been but very lately set at liberty; as we hear, not long
after, of plagues being very frequent in different parts of that
continent. In England it assumed somewhat of a new form towards the end
of the fifteenth century; being then known by the name of the English
Sweating Sickness. But, except in the greater propensity to sweat,
the disease appears not to have differed from the true plague. The
sweating sickness first made its appearance in the army of Henry VII,
when he landed at Milford in 1483; and that year invaded London, where
it continued only from the 21st of September to the end of October.
It returned in 1485, 1506, 1517, 1528 and 1551; since which time it
has not been known in Britain. In 1517 it was extremely violent and
mortal; sometimes killing the sick in three hours; and so general was
the infection, that, in some places, one half of the inhabitants
died. In 1528 it also raged with great violence; the sick sometimes
dying in four hours. The last attack, in 1551, was also very violent.
In 1529 it appeared in Holland and Germany, destroying great numbers
of people; but it hath not been observed, at least in any remarkable
degree, in those countries since that time. In the course of the 17th
century, various parts of Europe have suffered very much from the
plague in its usual form. Indeed (for reasons given in the subsequent
section) we can scarce suppose the pestilential contagion ever to
have ceased entirely. In 1603, London was visited with the plague;
and on this occasion the practice of shutting up infected houses was
first introduced.[23] In 1656 another plague took place in the same
metropolis, but does not appear to have made any violent attack. In
Naples it raged that year with great fury; destroying, according to
some accounts, fifteen thousand, according to others, twenty thousand,
a day. But these accounts the author of the Journal just quoted, with
great probability, supposes to have been exaggerated. Others say, that
four hundred thousand Neapolitans were destroyed by this infection;
so that we must at any rate believe it to have been very violent. In
the plague of London in 1665, immense numbers perished; and particular
accounts were published of this calamity; of which an abridgment is
given in the Appendix to this work, No. III. Since that time it has not
been known in Britain; but other parts of Europe have not been equally
fortunate. In the beginning of the eighteenth century it appeared in
several parts of the continent; particularly in Copenhagen in the year
1711; where it committed great ravages, as it had done at Dantzic two
years before; but in 1720 it appeared at Marseilles in France, where it
raged with such fury as to destroy sixty out of the hundred thousand
supposed to be the whole population of the place.[24] Since that time
France hath been free from the distemper; but in Sicily, the dominions
of the Ottoman Porte, and places adjacent, it hath been felt very
severely. In 1743 it was supposed to have destroyed two thirds of the
inhabitants of Messina. A particular account of its ravages was read
before the Royal Society of London by Dr. Mead. The following is taken
from Dr. Lobb’s Treatise on the Plague. “From the beginning of June to
the end of July, of forty thousand inhabitants, two thirds perished.
The disorders in the city were incredible. All the bakers died, and no
bread was baked for many days. The streets were full of dead bodies;
at one time from twelve to fifteen thousand remaining in the open air:
men, women and children, rich and poor, all together dragged to the
church doors. The vaults being full, and the living not sufficient
to carry the dead out of the city, they were obliged to put them on
funeral piles, and burn them promiscuously. Nothing was more shocking
than to see people, far above the common stations, go about begging for
a loaf of bread, when they could hardly walk, with their tumours upon
them; and few were in a state to help them. All these calamities did
not hinder the most execrable villanies, which were committed every
moment; and, though so few survived, the governor was obliged to make
several public examples.”

  [23] Journal of the Plague Year.

  [24] See Appendix, No. IV.

In the Turkish dominions, though we have not read of such extraordinary
devastations as formerly took place, yet we are assured that the
pestilence rages there very frequently. From 1756 to 1762 we have
histories of it by Dr. Russel and others, the substance of which
accounts is given in the Appendix, No. V. In the time of the great war
between the Turks and Russians, it found its way to Moscow, which city
it invaded in 1771. M. Savary says, it was brought thither by infected
merchandise from the store houses of the Jews; and that it carried
off two hundred thousand people. In the sixth volume of the Medical
Commentaries, however, we are told that it was brought from the army
by two soldiers; both of whom were carried into the military hospital,
and both died. The anatomist who dissected their bodies died also. The
infection quickly seized the hospital, and thence the whole city.
This happening in the beginning of the year, its progress was for some
time checked by the cold; but its ravages became greater as the summer
advanced. It raged most violently during the months of July, August
and September; in which time there were instances of its destroying
twelve hundred persons in a day. Twenty-five thousand died in the month
of September; in the course of which month scarce one in an hundred
of the infected recovered. Only seventy thousand, according to this
account, perished by the disease. The year 1773 proved very fatal to
Bassorah; where, as formerly mentioned, two hundred and seventy-five
thousand perished in the summer season, through the violence of the
distemper.[25] But in countries where the plague rages so frequently,
and where there are few that make observations with any accuracy, we
cannot expect complete histories of every attack made by it; neither
would the limits of this Treatise admit of a detail of them, though
there were. We know, however, that since the year we speak of, the
plague has ravaged Dalmatia, particularly in the year 1784, when
it almost desolated the town of Spalatro, destroying three or four
thousand of its inhabitants. Though some countries therefore have for a
number of years remained free from the attacks of this terrible enemy,
yet there are others where it is as it were stored up, and from whence
it may, on a proper occasion, break forth as formerly, and once more
spread ruin and desolation through the world.

  [25] An English gentleman, who resided in Bassorah at that time,
  preserved himself from the infection by retiring to a mud-house,
  where he had no communication with the inhabitants. Having a large
  quantity of Bengal cotton, he sold it to the people to wrap their
  dead in. The price was put in a basket, which he hauled up by a rope
  to his ware-room; lowering it again with the proportionate quantity
  of cloth. In the course of the summer he had an account of _seventy
  thousand_ winding sheets thus disposed of!

  (Transact. of a Society for improving Medical Knowledge.)



SECTION II.

  _Of the Countries where the Plague is supposed to originate.--The
  Influence of Climate in producing Diseases--And of the Moral Conduct
  of the Human Race in producing and influencing the same._


In considering the origin of a calamity so dreadful and so universal,
we might reasonably suppose that the fatal spots which gave rise to
it would long ago have been marked out and abandoned by the human
race altogether. But this is far from being the case. In the accounts
already given of various plagues, they are always said to have been
imported from country to country, but never to have originated in that
of the person who wrote of them. If a plague arose in Greece, we are
told it came from Egypt; if in Egypt, it came from Ethiopia; and had we
any Ethiopic historians, they would no doubt have told us that it came
from the land of the Hottentots, from Terra Australis Incognita, or
some other country as far distant as possible from their own. In short,
though it has been a most generally received opinion, that plagues
are the immediate effects of the displeasure of the Deity on account
of the sins of men; yet, except David and Homer (already quoted) we
find not one who has had the candour to acknowledge that a plague
originated among his countrymen on account of their sins in particular.
In former times Egypt and Ethiopia were marked out as the two great
sources of the plague; and even as late as the writings of Dr. Mead
we find that the same opinion prevailed. The Doctor, who attempts to
explain the causes of the plague, derives it entirely from the filth
of the city of Cairo, particularly of the canal that runs through it.
But later writers, who have visited and resided in Egypt, assure us
that the country is extremely healthy, and that the plague is always
brought there from Constantinople. It is true that Dr. Timone, in the
Philosophical Transactions, No. 364, tells us, that it appears from
daily observation, as well as from history, that the plague comes
to Constantinople from Egypt; but the united testimonies of Savary,
Volney, Mariti and Russel, who all agree that Egypt receives the
infection from Constantinople, must undoubtedly preponderate.

“The pestilence (says M. Savary) is not a native of Egypt. I have
collected information from the Egyptians, and foreign physicians who
have lived there twenty or thirty years; which all tended to prove the
contrary. They have assured me that this epidemic disease was brought
thither by the Turks, though it has committed great ravages. I myself
saw the caravelles of the Grand Signior, in 1778, unlade, according to
custom, the silks of Syria at Damietta. The plague is almost always
on board; and they landed, without opposition, their merchandise, and
their people who had the plague. It was the month of August; and, as
the disease was then over in Egypt, it did not communicate that season.
The vessels set sail, and went to poison other places. The summer
following, the ships of Constantinople, alike infected, came to the
port of Alexandria, where they landed their diseased without injury
to the inhabitants. It is an observation of ages, that if, during the
months of June, July and August, infected merchandise be brought into
Egypt, the plague expires of itself, and the people have no fears; and
if brought at other seasons, and communicated, it then ceases. A proof
that it is not a native of Egypt is, that, except in times of great
famine, it never breaks out in Grand Cairo, nor the inland towns, but
always begins at the seaports on the arrival of Turkish vessels, and
travels to the capital; whence it proceeds as far as Syria. Having come
to a period in Cairo, and being again introduced by the people of Upper
Egypt, it renews with greater fury, and sometimes sweeps off two or
three hundred thousand souls; but always stops in the month of June, or
those who catch it then are easily cured. Smyrna and Constantinople are
now the residence of this most dreadful affliction.”

M. Volney informs us, that the European merchants residing at
Alexandria agree in declaring that the disease never proceeds from the
internal parts of the country, but always makes its first appearance on
the sea-coasts at Alexandria; from thence it passes to Rosetta, from
Rosetta to Cairo, and from Cairo to Damietta, and through the rest of
the Delta. It is invariably preceded by the arrival of some vessel
from Smyrna or Constantinople; and it is observed, that if the plague
has been violent during the summer, the danger is greater for the
Alexandrians during the following winter.

To the same purpose, the Abbe Mariti says, “The plague does not usually
reside in Syria, nor is this the place where it usually begins. It
receives this fatal present from Egypt, where its usual seat is
Alexandria, Cairo or Damietta. The plague of 1760 came at once from
Cairo and Alexandria; to the latter of which it had been brought from
Constantinople. When it comes from that capital, as well as from the
cities of Smyrna and Salonica, it acquires a peculiar malignity; and
its activity never expands itself with more fury than in the plains of
Egypt, which it overspreads with incredible rapidity. It is observed,
that this plague, so destructive to Egypt, seldom attacks Syria; but
that the latter has every thing to dread from a plague hatched in the
bosom of Egypt.”

The testimony of these three authors, who have all been lately on
the spot, must certainly have very great weight, especially when
corroborated by that of Dr. Russel; for which see Appendix, No. V. But
still there is some difficulty. M. Savary informs us, that, _except
in cases of great famine_, the disease never breaks out in Cairo;
which certainly implies that in cases of famine it does originate in
the city itself; and Mariti, by saying that the Syrians have much
reason to dread a plague _hatched in the bosom_ of Egypt, undoubtedly
intimates that plagues sometimes do originate in Egypt. Smyrna and
Salonica likewise seem to come in for their share of the blame; and
Dr. McBride, in his Practice of Physic, informs us, that some parts
of Turky are visited by the plague once in six or seven years; and M.
Savary says, that Egypt is visited with it once in four or five years;
but if Egypt never receives it but from Turky, it would seem that the
plague could at least be no more frequent than in that country; or,
if the fact be otherwise, that the disease must either originate in
Egypt itself, or be brought to it from some other country than Turky.
Dr. Timone, in the paper already quoted,[26] tells us, that the plague
has taken up its residence in Constantinople; but that, though the
seeds of the old plague are scarce ever wanting, yet a new infection
is likewise imported from time to time. Thus, in attempting to find
out the countries where the plague originates, we are led in a circle.
Constantinople accuses Egypt, and Egypt recriminates on Constantinople.
Ethiopia, the most distant and least known of those countries which
in former times had any connexion with the more civilized parts of
the world, for a long time bore the blame of all; but the Jesuit
missionaries who resided long in Abyssinia (the ancient Ethiopia) do
not mention the plague as more common in that country than some others;
neither does Mr. Bruce, in the accounts he has published, take notice
of any such thing. Ethiopia could not speak for itself, by reason of
the ignorance and barbarity of its inhabitants; and Constantinople
is now very much in the same predicament. The investigation of this
subject therefore would require an accurate account of the climates
of those countries where the plague is found to commit the greatest
ravages, and a comparison of them with those which are now accounted
the most unhealthy in other respects, and likewise a comparison of the
diseases produced in the latter, with the true plague.

  [26] Philosoph. Transact. No. 364.

The most unhealthy climates now existing (those where the plague
commonly rages excepted) are to be met with in the hottest parts of the
world; the East and West Indies, the wastes of Africa, and some parts
of America. In all these, Dr. Lind, who has written a treatise on the
diseases incident to Europeans in hot climates, seems to lay the whole
blame upon the heat and moisture accompanying it. In the East Indies
Bencoolen, in the island of Sumatra, is the most unhealthy of all the
English settlements; but he informs us, that by building their fort
on a dry, elevated place, about three miles from the town, it became
sufficiently healthy. Next to this, Bengal is most subject to sickness;
for which he assigns the following reason: “The rainy season commences
at Bengal in June, and continues till October; the remainder of the
year is healthy and pleasant. During the rains, this rich and fertile
country is covered by the Ganges, and converted as it were into a
large pool of water. In the month of October, when the stagnated water
begins to be exhaled by the heat of the sun, the air is then greatly
polluted by the vapours from the slime and mud left by the Ganges, and
by the corruption of dead fish and other animals. Diseases then rage,
attacking chiefly such as are lately arrived. The distempers are fevers
of the remitting or intermitting kind; for, though sometimes they may
continue several days without sensible remission, yet they have in
general a great tendency to it. If the season be very sickly, some
are seized with a malignant fever, of which they soon die. The body
is covered with blotches of a livid colour, and the corpse, in a few
hours, turns quite livid and corrupted. At this time fluxes prevail,
which may be called bilious or putrid, the better to distinguish them
from others which are accompanied with inflammation of the bowels. The
island of Bombay has of late been rendered much more healthy than it
formerly was, by a wall built to prevent the encroachments of the sea,
where it formed a salt marsh; and by an order that none of the natives
should manure their cocoa-trees with putrid fish.

“Batavia, the capital of the Dutch East India dominions, is annually
subject to a fatal and consuming sickness. Here the Dutch, in
attempting to make this, their capital in India, resemble their cities
in Europe, have adorned it with canals or ditches, intersecting
each other, running through every part of it. Notwithstanding the
utmost care to keep these clean, during the rainy season, and after
it, they become extremely noxious to the inhabitants, but especially
to strangers. It has been remarked, that the sickness rages with
the greatest violence when the rains have abated, and the sun has
evaporated the water in the ditches, so that the mud begins to appear.
This happened in 1764, when some British ships of war had occasion
to stay for a little time at Batavia. The stench from the mud was
intolerable; the fever was of the remitting kind; some were suddenly
seized with a delirium, and died in the first fit; but none survived
the attack of a third. Nor was the sickness at that time confined
to the ships; the whole city afforded a scene of disease and death;
streets covered with funerals, bells tolling from morning to night, and
horses jaded with dragging the dead in herses to their graves. At that
time a slight cut of the skin, the least scratch of a nail, or the most
inconsiderable wound, turned quickly into a putrid, spreading ulcer,
which, in twenty-four hours, consumed the flesh, even to the bone.
Besides these malignant and remitting fevers, which rage during the wet
season in the unhealthy parts of the East Indies, Europeans, especially
such as live intemperately, are also subject to fluxes, and to an
inflammation, or disease of the liver; which last is almost peculiar to
India, and particularly to the Coromandel coast.”

In the same work we have an extract from Mr. Ives’s journal of a
journey from India to Europe by land. “Gambroon in Persia, says he,
is very unhealthful. Few Europeans escape being seized with putrid
intermitting fevers, which rage from May to September, and are often
followed with obstructions of the liver. Various authors who have
treated of Gambroon, do, as well as the present English factory, impute
its unhealthfulness, during the summer months, to the noxious effluvia
with which the air is contaminated, from the great quantities of
blubber fish left by the sea upon the shore, and which very soon become
highly offensive. In the rainy seasons, at the island of Karee, in the
Persian Gulf, intermitting fevers and fluxes are the usual distempers.
On our arrival at Bagdad (supposed to contain 500,000 souls) we found
a purple fever raging in the city; but though it was computed that an
eighth part of the inhabitants were ill, yet the distemper was far from
being mortal. Here we were informed that the Arabs had broken down the
banks of the river near Bassorah, with a design to cover with water
the deserts in its neighbourhood. This, it seems, is the usual method
of revenge taken by the Arabs for any injury done them by the Turks
at Bassorah; and was represented to us as an act of the most shocking
barbarity, since a general consuming sickness would undoubtedly be
the consequence. This was the case fifteen years before, when the
Arabs, by demolishing the banks of this river, laid the environs of
Bassorah under water. The stagnating and putrefying water in the
adjacent country, and the great quantity of dead and corrupted fish
at that time lying upon the shore, polluted the whole atmosphere, and
produced a putrid and most mortal fever, of which between twelve and
fourteen thousand of the inhabitants perished; and, at the same time,
not above two or three of the Europeans who were settled there escaped.
The effects of the violent heats we endured were, an entire loss of
appetite, a faintness and gripes, with frequent and bilious stools;
which greatly exhausted our strength. My stomach was often so weak,
that it could receive only a little milk. Several of us became feverish
through the excessive heat, and were obliged to have recourse to gentle
vomits, &c. Though we were furnished with the most ample conveniencies
for travelling, which money, or the strongest recommendations to the
principal christians, as well as mahometan chiefs, could procure,
and had laid in a quantity of excellent madeira, claret, and other
provisions, &c. yet most of us suffered in our constitutions by this
long and fatiguing journey.”

On these climates in general Dr. Lind observes, that in well cultivated
countries, such as China, the air is temperate and wholesome; while
the woody and uncultivated parts prove fatal to multitudes accustomed
to breathe a purer air. In all places also, near the muddy and impure
banks of rivers, or the foul shores of the sea, mortal diseases are
produced from the exhalations, especially during the rainy season.
“There is a place near Indrapour, in Sumatra, where no European can
venture to remain, or sleep one night on shore, during the rainy
season, without running the hazard of his life, or at least of a
dangerous fit of sickness; and at Podang, a Dutch settlement on
Sumatra, the air has been found so bad, that it is commonly called the
Plague-Coast. Here a thick, pestilential vapour or fog arises, after
the rains, from the marshes, which destroys all the white inhabitants.”

In treating of the diseases of Africa, the same author takes notice of
those of Egypt; which country, he says, is rendered unwholesome by the
annual inundation of the Nile, and being surrounded on three sides by
large and extensive deserts of sand, by which means it is exposed to
the effects of that noisome vapour, which, during the summer months,
arises from sultry, hot sand. He doth not, however, say, that the true
plague originates in this country, either from the inundation of the
Nile or any other cause. On the climate of Egypt I shall once more
quote M. Savary, who is a strenuous advocate for its healthiness, and
is at pains to confute the opinion of Mr. Pauw, and others, who assert
the contrary. “Mr. Pauw (says he) pretends, that at present Egypt is
become, by the negligence of the Turks and Arabs, the cradle of the
pestilence; that another epidemical disease, equally dreadful, appears
here, by the caravans of Nubia; that the culture of rice engenders
numerous maladies; that the want of rain and thunder occasions the
air of the Thebais to acquire a violence that ferments the humours
of the human body, &c.” “These assertions (M. Savary observes) have
an air of probability, which might impose on people who have not
lived in Egypt; but Mr. Pauw has ventured opinions in his closet,
without the guidance of experience. In vallies, indeed, enclosed by
high mountains, where the atmosphere is not continually renewed by
a current of air, the culture of rice is unwholesome, but not so,
near Damietta and Rosetta. The plains are nearly on a level with the
sea; neither hill nor height impedes the refreshing breath of the
north, which drives the clouds and exhalations off the flooded fields
southwards, continually purifies the atmosphere, and preserves the
health of the people; so that the husbandmen who cultivate the rice are
not more subject to diseases than those who do not. The heats of the
Thebais certainly surpass those of many countries under the equator.
Reaumer’s thermometer, when the burning breath of the south is felt,
sometimes rises to thirty-eight degrees above the freezing point,[27]
often to thirty-six. Were heat the principle of diseases, the _Said_
(Upper Egypt) would not be habitable; but it only seems to occasion a
burning fever, to which the inhabitants are subject; and which they
cure by regimen, drinking much water, and bathing in the river: in
other respects they are strong and healthy. Old men are numerous, and
many ride on horseback at eighty. The food they eat in the hot season
contributes much to the preservation of their health; it is chiefly
vegetables, pulse and milk. In Lower Egypt, the neighbourhood of the
sea, the large lakes, and the abundance of the waters, moderate the
sun’s heat, and preserve a delightful temperature. Strabo and Diodorus
Siculus, who long lived here, did not think the country unhealthy.
There is, indeed, an unwholesome season in Egypt. From February till
the end of May, the south winds blow at intervals, and load the
atmosphere with a subtile dust, which makes breathing difficult, and
drive before them pernicious exhalations. Sometimes the heat becomes
insupportable, and the thermometer suddenly rises twelve degrees. The
inhabitants call this season _Khamsin, fifty_; because these winds are
most felt between Easter and Whitsuntide; during which season they eat
rice, vegetables, fresh fish and fruit; bathing frequently, and using
plenty of perfumes and lemon juice; with which regimen they prevent the
dangerous effects of the Khamsin. But it must not be supposed that this
wind, which corrupts meat in a few hours, blows fifty days. Egypt would
become a desert. It seldom blows three days together; and sometimes is
only an impetuous whirlwind, which rapidly passes, and injures only
the traveller overtaken in the deserts. When at Alexandria a tempest
of this kind suddenly arose, driving before it torrents of burning
sand, the serenity of the sky disappeared, a thick veil obscured the
heavens, and the sun became blood-coloured. The dust penetrated even
the chambers, and burnt the face and eyes. In four hours the tempest
ceased, and the clearness of the day appeared. Some wretches in the
deserts were suffocated, and several I saw brought to appearance dead;
some of whom, by bathing in cold water, were restored to life.”

  [27] Water boils at eighty degrees of this thermometer.

The internal parts of the continent of Africa are but little known.
The northern parts, containing the States of Barbary, are sufficiently
healthy; the middle parts of the western coast, known by the names
of Negro-land, Guinea, &c. are extremely unhealthy and pernicious to
strangers. Dr. Lind informs us, that, at a distance, this country
appears in most places flat, covered with low, suspended clouds; and
on a nearer approach heavy dews fall in the night time; the land being
every morning and evening wrapped up in a fog. The ground is clothed
with a pleasant and perpetual verdure, but altogether uncultivated,
excepting a few spots, which are generally surrounded with forests or
thickets of trees, impenetrable to refreshing breezes, and fit only for
the resort of wild beasts. The banks of the rivers and rivulets are
overgrown with bushes and weeds, continually covered with slime, which
sends forth an intolerable stench. All places however are not equally
unhealthy; nor is any place equally unwholesome at all times of the
year. It is only with the rainy season that the sickness commences.
But as it would be tedious, and not answer our present purpose, to
enumerate those places which are healthy, and those which are not,
I shall only extract from Dr. Lind’s work an account of one which
seems to be as bad as can well be imagined. It is called _Catchou_, a
town belonging to the Portuguese, and situated in 12 degrees N. lat.
“I believe (says the author of this account) there is scarce to be
found on the whole face of the earth a more unhealthy country than
this during the rainy season. We were thirty miles distant from the
sea, in a country altogether uncultivated, overflowed with water,
surrounded with thick, impenetrable woods, and overrun with slime. The
air was vitiated, noisome and thick, insomuch that the lighted torches
or candles burnt dim, and seemed ready to be extinguished; even the
human voice lost its natural tone. The smell of the ground, and of
the houses, was raw and offensive; but the vapour arising from the
putrid water in the ditches was much worse. All this, however, seemed
tolerable, in respect of the infinite numbers of insects swarming every
where, both on the ground and in the air; which, as they seemed to
be produced and cherished by the putrefaction of the atmosphere, so
they contributed greatly to increase its impurity. The wild bees from
the woods, together with millions of ants, overran and destroyed the
furniture; while swarms of cock-roaches often darkened the air, and
extinguished even the candles in their flight; but the greatest plague
was the musquetoes and sand-flies, whose incessant buzz and painful
stings were more insupportable than any symptom of the fever. Besides
all these, an incredible number of frogs, on the banks of the river,
made such a constant and disagreeable croaking, that nothing but being
accustomed to such an hideous noise, could permit the enjoyment of
natural sleep. In the beginning of October, as the rains abated, the
weather became very hot, the woods were covered with abundance of dead
frogs, and other vermin, left by the recess of the river; all the
mangroves and shrubs were likewise overspread with stinking slime.”

No doubt these accounts are calculated to inspire us with dreadful
ideas of the countries mentioned in them. What could be done by the
putrefaction of dead animals and vegetables, certainly would be done
here; the produce, however, was not the true plague; not even in
_Catchou_; but “a sickness which could not well be characterised by
any denomination commonly applied to fevers; it however approached
neared to what is called a nervous fever, as the pulse was always
low, and the brain and nerves principally affected,” &c. Certainly
if in any country heat, moisture and putrefaction could produce a
plague, it would be in this. Yet, in all the places we have mentioned,
whether India, Arabia, Egypt, or Guinea, (and we might go through the
whole world in the same manner) we have not been able to find either
moist heat or dry heat, even when aided by putrefaction, insects, and
nastiness of all kinds (not justly chargeable upon any climate;) I
say, we have not found the united powers of all these able to produce
a plague. Nay, it is even doubtful whether climates can produce those
inferior diseases above mentioned. Even Dr. Lind, who appears to be
so willing to ascribe every thing to climate, seems embarrassed in
this respect. “There are many difficulties (says he) which occur in
assigning a satisfactory reason, why in some countries, as in those
between the tropics, heavy and continual rains should produce sickness;
while in other places, especially in the southern parts of Europe,
a want of rain for two or three months in summer brings on diseases
almost similar. Upon this occasion (adds the Doctor) I cannot help
observing, that there is hardly a physical cause which can be assigned
for the produce of any disease, that will not admit of some exceptions:
thus, not only the woods and morasses in Guinea are tolerably healthy,
with some exceptions, in the dry season; but a few instances might be
produced of towns surrounded with marshes and a foggy air, where the
inhabitants suffer no inconvenience from their situation, even during
the rainy season. Do the impetuous torrents of water poured from the
clouds during the rainy seasons, in tropical countries, contain what
is unfriendly to health? Thus much is certain, that the natives of
such countries, especially the mulattoes, avoid being exposed to these
rains as much as possible, and when wet with them immediately plunge
themselves into salt water, if near it. They generally bathe once a
day, but never in the fresh water rivers, when overflown with rains,
preferring at such times the water of springs. Is the sickness of these
seasons to be ascribed to the intense heat of the then almost vertical
sun; which frequently, for an hour or two at noon, dispels the clouds,
and with its direct beams instantly changes the refreshing coolness of
the air into a heat almost insupportable?

“Further: As the season of those sudden and terrible storms, called
the hurricanes, in the East and West Indies, and tornadoes on the
coast of Guinea, partly coincides with that of the rains, do these
dreadful tempests in any measure contribute to produce the prevailing
sickness at those times? It was remarkable one year at Senegal, that,
in the beginning of the rainy season, in the night succeeding one of
these tornadoes, a great number of the soldiers, and two thirds of
the English women, were taken ill, this garrison before having been
uncommonly healthy.

“Lastly: Is it not more probable, as in those countries the earth for
six or eight months in the year receives no moisture from the heavens
but what falls in dews, which every night renew the vegetation, and
reinstate the delightful verdure of the grass, that the surface of the
ground in many places becomes hard and incrustated with a dry scurf,
which pens up the vapours below, until, by the continuance of the
rains for some time, this crust is softened, and the vapours set free?
That these dews do not penetrate deep into the surface of the earth,
is evident from the constant dryness and hardness of such spots of
ground, in those countries, as are not covered with grass and other
vegetables. Thus the large rivers, in the dry season, being confined
within narrow bounds, leave a great part of their channel uncovered,
which, having its moisture totally exhaled, becomes a hard, dry crust;
but, no sooner the rains fall, than, by degrees, this long parched up
crust of earth and clay gradually softens, and the ground, which before
had not the least smell, begins to emit a stench, which in four or five
weeks becomes exceeding noisome; at which time the season of sickness
commences.”

From these quotations it must certainly appear, that the author himself
is dissatisfied with his theory; and that, though in the outset he
thought heat and moisture, assisted by the exhalations from putrid
animal and vegetable substances, sufficient to produce the disorders
of which he treats, yet, on a more minute investigation, he is obliged
to acknowledge, that something inexplicable still remains. This he
now wishes to solve by unknown properties in the water, by confined
exhalations, &c. But as the consideration of these things belongs
properly to the next section, I shall here only remark, that there hath
not yet been given any satisfactory account of the origin of epidemic
diseases of what I call the _inferior_ kind, much less of the true
plague, which stands above them all, as I have already said, like the
serpent Python above other serpents.

To what has been quoted from Dr. Lind, I shall here subjoin the
testimony of Dr. Clark, who had an opportunity of observing the
epidemic diseases which raged at Bengal in 1768 and 1769. These were,
“the remittent fever and dysentery, which begin in August, and continue
till November. During the beginning of the epidemic, the fever is
attended with extreme malignity and danger; frequently carrying off
the patient in twelve hours; and, if not stopped, generally proves
fatal on the third or fourth day. In August the remissions are very
imperceptible; in October they become more distinct; and, as the cold
weather comes on, the fever becomes a regular intermittent. At that
time, too, the putrid dysentery begins to rage with the fever. These
diseases were very fatal to many Europeans, particularly new comers,
in 1768. But in the year 1770, when there was a scarcity of rice, it
was computed, that about eighty thousand natives, and one thousand
five hundred Europeans, died at Bengal. The streets were covered
with funerals; the river floated with dead carcases; and every place
exhibited the most melancholy scenes of disease and death. During
the sickly seasons at Bengal, the uncertainty of life is so great,
that it frequently happens that one may leave a friend at night in
perfect health, who shall not survive next day. There have been several
instances of persons who have returned home in a state of perfect
health from performing the last duties to a deceased friend, and have
next day been numbered with the dead. But the cool, agreeable season,
from December to March, is productive of no prevailing diseases.
The complaints to be met with are in general the consequences, or
remains, of the diseases of the former period. The complaints which
the Europeans are subject to in the dry months are, the cholera and
diarrhœa. Fluxes and fevers are then seldom epidemic; and, when they do
happen, are not attended with much danger.

“At Batavia the rainy season is from November to May, during which time
malignant, remitting and continued fevers and the dysentery rage with
great fatality. Captain Cook, in his first voyage, arrived here in
October 1779; the whole crew, excepting Tupia, a native of Otaheite,
being in the most perfect health. But, in the course of nine days, they
experienced the fatal effects of the climate, and buried seven people
at Batavia. On the 3d of December, the ship left the harbour. At that
time the number of sick amounted to forty; and the rest of the ship’s
company were in a very feeble condition. When the ship anchored at
Prince’s Island, in the Straits of Sunda, the sickness increased, and
they buried twenty-three persons more in the course of about six weeks.
The Grenville Indiaman, which touched at this island in 1771, suffered
equally from the malignity of the air. A few were taken on board, when
the ship sailed from Batavia, ill of a malignant fever; which spread
by contagion at sea, and carried off great numbers. I visited several
in this ship, when she arrived at China, who were reduced to mere
skeletons, by the duration of the fever and dysentery; both of which
were most certainly propagated by contagion.

“Those parts of Sumatra lying immediately under the line are
continually subject to rain, and the ground near the shore is low, and
covered with thick trees and underwood. The heat being intense, noisome
fogs arise, which corrupt the air, and render the country fatal to
foreigners. The land of North Island, which lies on this coast, near
the beginning of the Straits of Sunda, appears at a distance finely
variegated; but at the place where the wood and water are to be got it
is low, and covered with impenetrable mangroves, and infested with a
variety of insects. It is here that most of the East India ships take
in wood for their homeward voyage. A Danish ship, in 1768, anchored
in this island, and sent twelve of her hands on shore to fill water;
where they only remained two nights. Every one of them was seized with
a fever, whereof none recovered: but although the ship went out to
sea, none, except the twelve who went on shore, were attacked with the
complaint.”

With regard to China, this author says, that the “port of Canton is
by no means so healthy as is generally represented. The comparative
degree of health which Europeans enjoy here has been ascertained from
the instances of the supercargoes, which is, however, a very erroneous
standard. The generous and regular way in which these gentlemen live,
for the most part, exempts them from diseases; and, being but few in
number, no great mortality can take place among them. But seamen, who
never observe much regularity in their way of living, who work hard in
the day time, are but badly clothed, and not provided against the damps
and cold north-easterly winds at night, seldom fail to be afflicted
with the diseases already mentioned (fevers and fluxes.) Even the
factors of different nations, who reside here for any considerable
time, experience all the inconveniences peculiar to any sultry climate:
florid health is a stranger to their countenances; their constitutions
are soon weakened and enfeebled; and they become subject to habitual
fluxes and other complaints, the usual consequences of too great
relaxation.”

The climate of the southern part of China, according to the same
author, is excessively hot during the summer months. Even in September
and October, when the nights are cold, the days continue to be sultry.
The cold months are, December, January and February; “and during this
time the vicissitudes of the weather are more quick than in any other
part of the world. When the wind is northerly, and the thermometer
at 46, upon a change of the wind to the south, it is next day up to
60 or 70. People who reside here are always at a loss with regard to
their clothing; one day finding a silk coat sufficient; and the next,
upon a sudden change of wind, finding it necessary to wear a flannel
waistcoat.”

On the subject of climate, therefore, I must conclude with the
following observations:--First: That, as the diseases above mentioned
are produced both in moist and dry countries, in those in the torrid
and those in the temperate zone, they can neither be the offspring of
moisture or drought, of heat or cold, of septics or antiseptics, but of
something not yet discovered. Second: That, upon fair investigation, it
does not appear, that ancient historians have been able to ascertain
the origin of any plague whatever: they have universally ascribed it
to the anger of the Deity, while their own pride would never allow
it to have originated in any country with which they were connected.
Third: It doth not by any means appear, that the climates of those
countries, where the plague is known to be most common, are at all
inferior to those already described, excepting the very circumstance
of having the plague frequently in them: nay, indeed, that they
are equally bad. Nobody will pretend to argue, that the climate of
Asia Minor, of Greece, of the Morea, or of any of the countries most
infected with the plague, was, or is, worse than that of _Catchou_ in
Africa, already described; yet it is certain, that we have a number
of testimonies that the plague has ravaged Asia Minor, while we have
not one of its visiting _Catchou_. Ancient Greece, the Peloponnesus
(Morea) and Asia Minor, were accounted healthy and fine countries; and
modern travellers assure us, that they have not degenerated in this
respect; yet these countries are desolated by the plague, while the
unwholesome regions above described are entirely free from it, unless
imported from some other quarter. To give this matter, however, as
fair a discussion as possible, I shall here consider the account we
have of the climate of Bassorah, given by the gentleman residing there
in 1780; whose case, in the remitting fever, is given, Appendix, No.
VI. “The overflowing of the Euphrates, and its waters stagnating in
the desert, have always been accounted primary causes of epidemical
diseases at Bassorah. The great floods from the melting of the snow
on the mountains of Diarbekir, the ancient Assyria, happened in the
year 1780, early in the month of May, when the heats in Persia and
Arabia begin to be excessive. The desert, which reaches to the gates of
Bassorah, is, for many miles, incrusted with a surface of salt; which,
when mixed with the stagnated waters, and exposed to the sun, produces
the most noxious effluvia. As early as the 25th of May, the town was
surrounded by a salt marsh, the heated steam arising from which was, at
times, almost intolerable; but the canal that runs through a great part
of the city being filled with the bodies of animals, and all kinds of
putrid matter; and, at low tides, all these substances exposed to the
sun, made the air in the town scarce supportable; and, being totally
destitute of police, the streets were in many places covered with human
ordure, the bodies of dead dogs and cats, &c. which emitted a stench
more disagreeable and putrid than any thing I ever experienced in my
life. As to the degree of solar heat, it far exceeded what I conceived
the human frame to be capable of bearing. The sensation under this heat
was totally different from what I had ever experienced; it resembled
the approach of an heated substance to the body. The quicksilver, in
Fahrenheit’s thermometer, rose to between 156 and 162 degrees.[28] From
the 30th of May I never saw it so low as 156, but generally between 158
and 160. After I left Bassorah I was told that it rose still higher.
In the coolest part of the house, with the aid of every invention to
decrease the heat, the quicksilver rose to 115; but after I came away,
I was informed that it rose still higher, even at seven in the morning,
the hour which we accounted the coolest in the day. Once the heat was
said to be so intolerable, that no one could expose himself to it
long enough to observe the thermometer in the sun. Some of the oldest
inhabitants of Bassorah said that they never remembered to have heard
of such a heat in any part of Persia or Arabia. The natives of the
country appeared more alarmed at the heat than the Europeans: nothing
could induce them to expose themselves to the sun after ten o’clock. I
left Bassorah for Aleppo on the 30th of May. On our arrival at Zabira,
the heat was so intense, that even the Arabs sunk under it.”

  [28] Spirit of wine boils at 175.

From this account it was natural to expect that violent sickness would
ensue. This was the opinion of the inhabitants, and they were not
deceived. The sickness, however, was not the true plague, but a violent
remitting fever; and even this did not originate in the city itself,
but was observed to approach from Asia Minor, ravaging Diarbekir, and
keeping the course of the Tigris, to Bagdad, where many died. From
thence it followed the course of the Euphrates to Bassorah, and for
about twenty miles lower. The opposite, or Persian shore, though within
a few miles, was exempted, and it did not spread more than twenty
miles into the desert.[29]

  [29] Transactions of Society for improving Medical Knowledge.

I might now proceed to give an abstract of what has been said of the
power of climate in producing diseases on the Western Continent, and
West India islands; but as this belongs more especially to the second
part of this Treatise, I shall here pass it over, as well as what Dr.
Smith has said of the climate of Greece, in the Medical Repository,
and which he endeavours to prove to be similar to the climate of
North America. But, before we proceed to consider what diseases may
be produced by _climate_ alone, it is proper to discuss the question,
how far man is naturally subject to diseases of any kind? Many, no
doubt, will be apt to suppose this a very absurd question; for as man
is now, by nature, subject to death, it seems to follow, that he is
also naturally subject to disease, as the means of bringing on death.
But, however plausible this may appear, experience shows, that disease
and death are not always connected. Many people die of mere old age;
the powers of life being exhausted, and the system so far decayed,
that the various parts of it can no longer perform their offices. On
the other hand, a disease destroys by attacking some particular organ,
and either totally consuming or altering it in such a manner, that
it disturbs the vital operations, while yet strong and vigorous. We
may therefore compare the death of a person from mere old age to the
natural extinction of a candle when the tallow is totally consumed;
and death from disease, to the blowing out of a candle while a part
of it remains, and might have burned for a considerably longer time.
Thus I am inclined to consider all diseases as merely accidental; and
this with the greater certainty, because, though, in common with other
believers in revealed religion, I think that death is the consequence
of Adam’s transgression, yet I do not find that disease of any kind was
threatened except in cases of positive transgression, long after the
days of Adam.

Every one allows, that, though some diseases are natural, some are
likewise artificial; but nobody hath attempted to draw the line of
demarcation between them. Every thing is charged upon climate, heat,
moisture, drought, vapour, &c. and yet, upon examination, we shall find
the utmost difficulty in deriving a single disease from the causes we
assign. No person in his senses will say that Adam, in consequence of
eating the forbidden fruit, became liable to the venereal disease. As
little can we say for the gout, the stone, or the dropsy; and if we
cannot particularize the diseases to which he became naturally liable,
we have no right to say that any kind of disease became natural to
him in consequence of his transgression. If, therefore, death itself,
originally not natural to man, did yet take place in consequence of
his moral conduct; and if diseases, without number, have arisen among
his posterity, though not natural to him in consequence of his first
transgression, we have equal reason to believe that these diseases
have taken place among them in consequence of their moral or rather
_immoral_ conduct, in totally deviating from the line prescribed them
by their Maker, and following others of their own invention; and this
will appear the more probable, when we consider, that, long after
mankind became subject to death, we find diseases, particularly the
pestilence, threatened as the consequence of subsequent transgressions.

If, without taking scripture into consideration, we attend only to
what may be gathered from profane history, we find the testimony of
all the ancients concurring in one general point, viz. that in times
of great antiquity men were more healthy, and even stronger, than in
the times when those authors lived. This is taken notice of by Homer,
when comparing the strength of men in the time of the Trojan war with
those in his days, about two centuries later.[30] Virgil, who lived in
much more modern times than Homer, carries his ideas of the degeneracy
of man much farther; and informs us, that Turnus, when fighting with
Æneas, took up and threw a stone which twelve men of that time could
not have lifted. Now, though we know that both these accounts are
fabulous, yet they perfectly coincide with the voice of historians of
all nations; for we are universally told, that the first inhabitants
of countries were a brave, hardy people, living according to the
simplicity of nature, free from diseases, and attaining to a good old
age.

  [30]

  A pond’rous stone bold Hector heav’d to throw,
  Pointed above, and rough and gross below;
  Not _two_ strong men th’ enormous weight could raise,
  Such men as live in these degenerate days.

    Iliad, B. xii.


This is so conformable to what is generally said at present, probably
very often by rote, without regard to rational evidence, that, were
we so inclined, ample room might be found for declamation against
modern luxuries, particularly the practice of drinking ardent spirits,
as pernicious to health, and destructive to the human body. On this
subject, however, we may once for all observe, that, although we find
ample evidence of the baleful influence of these liquors in producing
other diseases, yet we find none of their ever having had any share
in the production of an epidemic or general disease among mankind.
In ancient times the art of distillation seems to have been unknown;
so that whatever mischief was done in those days must have been done
by wine, or other fermented liquors. In modern times, though the use
both of fermented liquors and ardent spirits is undoubtedly carried
to excess, yet there is no evidence of their producing an epidemic,
or even making it more violent or general than it would otherwise
have been. Dr. Cleghorn, having spoken largely of the manner of
living of the natives in Minorca, proceeds thus: “I should next give
a circumstantial account of the diet and way of life of the British
soldiers in this island; but as this would be a disagreeable task,
I shall only observe, that the excess of drinking is among them
an universal vice, confirmed into habit. But, however different
the Spaniards be from the English, in their meat, drink, exercise,
affections of the mind, and habit of body; yet the health of both
nations is equally influenced by the seasons. An epidemical distemper
seldom or never attacks the one class of inhabitants without attacking
the other also; and, surprising as it may appear, it is nevertheless
true, that the peasants, remarkable for temperance and regularity, and
the soldiers, who, without meat and clothes, frequently lie abroad
drunk, exposed to all weathers, have diseases almost similar, both as
to their violence and duration.”

There can be no doubt that excess in drinking hath put an end to the
lives of many individuals; and it hath been observed, that such as
attempt to preserve themselves from the plague by the use of strong
liquors, have generally fallen sacrifices to it;[31] but this cannot
prove that such excess would have brought on the distemper without some
other cause. It hath been certainly found, that excess in drinking or
eating, excess in venery, excessive fatigue by labour, watching, study,
&c. will all make an epidemic disease more violent when it attacks a
particular person; but no experience hath yet shown that the _first_
person seized with an epidemic always fell under this description. All
that can be said on the subject is, that, by such excesses as have
already been described, the body is prepared for receiving the disease,
by an exhaustion, or evaporation (if we please to call it so) of the
vital principle; as wood is prepared for burning by the evaporation
of its moisture; but as wood, however dry, will not burn without the
contact or application of fire, so neither will the body, though ever
so well prepared, be attacked by any epidemic, unless the true cause of
that epidemic be also applied.

  [31] See Sec. IV. Preventives of the Plague.

Thus we are still disappointed in our attempts to discover the origin
of the plague. We have seen that the most unhealthy climates in the
world do not produce it of themselves; neither can the conduct of any
individual bring it upon himself, without an unknown _something_, which
nobody has yet found out. It was this difficulty of finding out the
natural cause, which certainly induced by far the greatest number of
writers on the subject to ascribe it to Divine Power; and even as late
a writer as Dr. Hodges tells us, that he believes in the _to Theion_,
the “finger of God,” in the plague, as much as any body. As for those
who have endeavoured to account for the origin of this distemper
from an inquiry into natural causes, and conclusions drawn from the
late experiments on air, they have totally failed; as will be fully
elucidated in the following section.

If then we are to believe that diseases, especially those called
epidemics, among which the plague holds the first place, have arisen
in consequence of a certain line of conduct adopted by the human race,
or have been inflicted by the Deity as punishments on that account, we
are to look for their origin among those to whom the Deity principally
manifested himself; that is, the Jews, and nations who interfered with
them. Among the Jews we hear of the first general plague distinctly
mentioned; viz. the three days pestilence of David, and to which it is
possible that Homer alludes in his Iliad. Next to this is the great
plague of 767 B. C. said to have spread all over the world. This
coincides with the time of Pul, king of Assyria; who, having overthrown
the ancient kingdom of Syria, turned his arms against that of Israel,
and no doubt extended his conquests among the eastern nations, as we
know very well the Assyrian monarchs did. As the ten tribes, ever after
their separation from the house of David, had in a manner totally given
themselves up to idolatry, we are not to wonder if the pestilence, so
frequently threatened by Moses, was very common, or, as physicians
term it, _endemic_, among them. Thus, whatever enemy invaded the
country, would almost certainly carry the disease along with them, and
spread it among the other nations with whom they afterwards had any
connexion. At this time, or even before this, during the wars of Syria
with Israel and Judah, this dreadful pestilence might begin; but, as
to its being all over the world in any particular year, I do not see
how it can be ascertained; because there are no general histories of
the world in those early times. It appears more probable that this
general pestilence took place at the time that Sennacherib’s army was
destroyed. I have no doubt, indeed, for the reasons already given,
that the plague had infected Sennacherib’s army before he went into
Ethiopia. In that country, in all probability, he would leave it; and,
after his return to Judea, when the dreadful catastrophe befel him
of an hundred and eighty-five thousand of his men being destroyed in
one night, there can be no doubt that the remains of his army would
carry with them the seeds of a most malignant pestilence, capable of
spreading destruction far and wide. It is true, we are not directly
told, in Scripture, that the Assyrian army was destroyed by a plague,
but that the angel of the Lord destroyed them; but, as this expression
is quite similar to what we read of the pestilence in David’s time,
there can be but little doubt that the means of destruction made
use of in both cases were the same. Josephus expressly says, that
Sennacherib’s army was destroyed by a pestilence. Neither are we to
conclude, because this pestilence was miraculous, that it therefore
certainly killed every one on whom it fell; or that it would not infect
those who came near the sick, as any other disease of the kind would do.

From the same source may we derive the propensity in the Carthaginian
armies to pestilential disorders. Carthage was a colony of Tyre; and
the Tyrians were in close alliance with the Jews, during the reigns
of David and Solomon, and very probably afterwards; so that from
them the distemper might be communicated in such a manner as to be
almost endemic; and thus hardly an army could be sent out but what
would have the infection with it, breaking out with violence now and
then, as occasional causes tended to give life to the contagion. It
is impossible, however, from the source just mentioned to trace the
plague of Athens, or the first plague in Rome; but it is very natural
to suppose that the violent one which raged in Rome, during the reign
of Titus, came from Jerusalem. That city had sustained a most dreadful
siege, and the obstinate and wretched inhabitants had endured such
calamities as have scarcely been recorded in the history of nations.
Among these calamities was a pestilence, which, in all probability,
would be conveyed to Rome, and there occasion the destruction already
mentioned.

But what seems to render this account of the origin of the plague more
probable is, that the Jews are to this day accused of propagating the
disease in those countries where it is most frequent. Baron de Tott
is of opinion that the plague in Constantinople originates among the
Jewish dealers in old clothes; for these avaricious dealers, purchasing
the infected goods, sell them indiscriminately to every one who will
buy, and that without the least care taken to remove the infection
from them; by which means it is no wonder to find the plague, as well
as other diseases, disseminated among them in great plenty. Dr. Russel
informs us, that the Jews are most liable to the plague, the most
fearful of it, and the most ready to fly from the infection. The Abbe
Mariti agrees in the same accusation against this unfortunate people.
“The Jews (says he) purchase at a low price the goods and wares which
remain when most of the family are deceased, and then store them up;
which, when the plague is over, they sell at a dear rate to those will
buy, and thus propagate the pestilential poison: again it kindles,
and presently causes new destruction. Thus this opprobrious nation,
preferring gold to life, sell the plague to mussulmen, who purchase it
without fear, and sleep with it, till, renewed of itself, it hurries
them to the grave.” M. Volney, though he does not mention the Jews in
such express terms as Mariti and Russel, yet agrees as to the mode of
its propagation in Constantinople, and the reason of its continuance
in that city. “It is certain (says he) that the plague originates in
Constantinople, where it is perpetuated by the absurd negligence of
the Turks, which is so great, that they publicly sell the effects of
persons dead of the distemper. The ships which go to Alexandria never
fail to carry furs and woolen clothes, purchased on these occasions,
which they expose to sale in the bazar of the city, and thereby spread
the contagion. The Greeks who deal in these goods are almost always the
first victims.”

Thus the account we have of the origin of the plague at present is,
that the city of Constantinople, having been long and deeply infected,
the infection is stored up through the avarice of the Jewish merchants,
who buy the goods and clothes of the infected. The stupidity of the
Turks allows these goods to be sold in Constantinople, or exported
freely to all parts to which their vessels sail, particularly to
Alexandria; where the avarice of the Greeks prompts them to buy without
examination or precaution, to the destruction of their own lives, and
of multitudes of others. Egypt being the principal place of traffick,
the plague is more frequent there than in other parts of the empire.
Syria is comparatively free from it; which M. Volney supposes to be
owing to the small number of vessels which come there directly from
Constantinople.

In this way we may, in a pretty plausible manner, account for the
origin of this distemper; viz. that it originally fell upon the Jews
as a punishment for their iniquities; that from the Jews it has been
at different times conveyed to other nations; and, by a mixture of
those nations, has, at times, become general all over the world. At
last it has, by the avarice of that people who first had been the
occasion of its being introduced into the world, become permanent in
Constantinople, whence it is still diffused among different nations in
proportion to their dealings with that capital.

But it may now be said, ‘Allowing the positions contended for to be
true in their utmost extent, how comes it to pass that the plague
hath not been general in every age and in every country? Since the
destruction of Jerusalem, the Jews have been dispersed over all
nations: if nothing then were wanting to produce a pestilence but
Jews and old clothes, no age or country ought to have been free from
it; nevertheless it is certain that violent plagues take place only
at particular times, with long intervals between; and of late the
pestilential disposition seems to have become much less frequent than
formerly; the western parts of Europe, particularly Britain, having
been free from it for a great number of years. There must therefore be
some cause, different from what has yet been mentioned, by which the
infection is occasionally roused from inactivity, and excited to spread
desolation all around.’

That there are predisposing causes to epidemic disorders, especially to
the plague, the most fatal of them all, is not denied. These prepare
the body for receiving the infection, but they will not, without that
infection, produce the disorder. Of these causes so many are to be
found in the conduct of mankind themselves, that we scarcely need to
look for them any where else. In looking over the histories of plagues,
we find them in an especial manner connected with famines and wars.
The former sometimes take place in consequence of the failure of crops
through natural causes; but, considering the general fertility of the
earth, we must certainly account it owing to bad management, in some
respect or other, that every country hath not as much laid up within
itself as would guard against the consequences of at least one or two
bad crops. Yet we believe there is not, at present, a country upon
earth in this predicament. If a crop fails any where, the inhabitants
must import largely, or they must starve. This is the case even in the
fertile regions of the East, where the earth produces in excessive
abundance,[32] and there is little or nothing of any kind of provision
exported to other countries. A remarkable instance of this occurred in
the plague at Aleppo, a history of which is given by Dr. Russel. He
tells us, that the winter of 1756 proved excessively cold, which was
followed by a famine next year. This account is confirmed by Mr. Dawes,
in a letter to the bishop of Carlisle.[33] He tells us, that in the
course of the winter many perished through cold; that the inhabitants
were reduced to such extremities, by the single failure of the crop in
1757, that women were known to eat their own children as soon as they
expired in their arms with hunger; and that human creatures might be
seen contending with dogs, and scratching for the same bone with them
in a dunghill. A dreadful plague followed; which, the two succeeding
years, swept off not fewer than sixty thousand in the city of Aleppo.

  [32] Herodotus says, that in his time the province of Babylonia
  produced commonly two hundred, and in plentiful years three hundred
  fold.

  [33] Philos. Transact. vol. liv.

It is probable that in this case the famine either produced the
plague, or made it worse than it would have otherwise been; and it is
not denied that the cold and bad season was the direct cause of the
famine. But as little can it be denied, that had the people, or their
governors, been so provident as to have laid up stores sufficient to
supply the country for one year, this famine would not have been felt.
As far, therefore, as the plague was connected with the famine, we must
own that it was chargeable on the human race themselves; not the sins
of this or that particular person, but a general deviation from the
task assigned them by their Maker, viz. that of cultivating the ground;
and, instead of this, spending their time in folly and trifling, to say
no worse.

But famines are occasioned not only by natural causes, but by wars;
in which mankind, acting in direct opposition to the laws of God and
nature, destroy and lay waste the earth, taking every opportunity of
reducing to extremity both those whom they call innocent and those whom
they call guilty. Thus vast multitudes are reduced to want, to despair,
and rendered a prey to grief, terror, and every depressing passion of
the human mind; they are exposed to every inclemency of the weather; to
the scorching heats of the day, and the chilling damps of the night; in
short, to every thing that we can conceive capable of predisposing the
body for the reception of diseases of the very worst kind. No wonder
therefore that war and pestilence go hand in hand; and, by taking a
review of the history of mankind, we shall see, that, always at those
times when the nations have been most actively employed in the trade
of butchering one another, then, or very soon after, they have been
afflicted with pestilence. To begin with the great plague of 767 B. C.
which coincides with the rise of the Assyrian empire: Till this time,
though there had been numberless wars, yet they were carried on upon a
much smaller scale than now, when great empires were to be set up, and
when the most distant nations were to be assembled in order to gratify
the pride and ambition of an individual. The Assyrians, we know,
penetrated into Ethiopia; but how far east or how far west they went,
we are not certainly informed. To their wars, however, we may with
reason ascribe the desolations occasioned by this first plague. From
Thucydides’s account of the plague at Athens, it seems plain that it
was occasioned, or at least rendered more violent, by the wars of the
Greeks with one another at that time. Had the Carthaginian army staid
at home when they went to war with Dionysius, tyrant of Syracuse,[34]
it is very probable that the pestilence would not have broke out among
them. The like may be said of the plague which broke out among them in
the time of Marcellus.[35] That in the time of Jugurtha, indeed, is
said to have been occasioned by locusts; but, had not vast bodies of
men been collected together for the purposes of war, the plague could
never have committed such ravages. The plague in the time of Titus
could not have been brought from Jerusalem, nor perhaps would it have
existed there, had not Titus made war against that city; and so of
others.

  [34] See Sec. i. p. 10.

  [35] Ibid. p. 12.

The plague which began in the reign of Justinian, as it was more
violent than any recorded in history, so it was preceded by wars
equally unexampled. The Romans had indeed for ages employed themselves
in war; but, by their constant superiority to every adversary, their
empire had become so amazingly extensive, that, whatever wars were
carried on in the remote provinces, the great body of the empire always
remained at peace; and this was the case even in their most violent
civil wars. On the accession of Alexander Severus, about the year 232,
they began to encounter enemies so numerous and formidable, that all
their power proved insufficient to repel them. In the tenth year of
Alexander’s reign, the Persians, having overthrown the ancient empire
of the Parthians, turned their arms against the Romans, and, though
frequently defeated at that time with great slaughter, renewed their
incursions in the reign of Gordian, about the year 242, when they
were in like manner defeated and obliged to retire. As these defeats,
however, did not at all affect the strength of the Persian empire,
the Romans still found them as formidable enemies as ever; while the
Goths, Sarmatians, Franks, and other northern nations, harassed them in
other parts. In the reign of Decius, who ascended the throne in 249,
they became extremely formidable, insomuch that the emperor himself,
with his whole army, was at last cut off by them. The consequence of
this was, that the empire was instantly invaded in many different
parts, and, though the barbarians were at times defeated, we never
find that the empire regained its former tranquillity. The Persians
and Scythians, taking advantage of the general confusion, invaded the
provinces next them, while the finishing stroke seemed to be given
to the Roman affairs by the defeat and captivity of Valerian by the
Persians.

This disaster, as may well be imagined, produced an immediate invasion
by numberless barbarians, while such multitudes of pretenders to the
imperial crown were set up, each asserting his claim by force of
arms, that the whole Roman territories were filled with bloodshed
and slaughter. At this time Gallienus, the son of Valerian, was the
_lawful_ emperor, if indeed we may apply the word to the domination
of such a monster. His mode of government may be imagined from the
following letter written to one of his officers in consequence of
a victory gained over an usurper named _Ingenuus_. “I shall not be
satisfied with your putting to death only such as have borne arms
against me, and might have fallen in the field: you must in every city
destroy all the males, old and young; spare none who have _wished_ ill
to me, none who have spoken ill of me, the son of Valerian, the father
and brother of princes. _Ingenuus_ emperor! Tear, kill, cut in pieces,
without mercy: you understand me; do then as you know I would do, who
have written to you with my own hand.” In consequence of this horrible
order, not a single male child was left alive in some of the cities of
Mœsia, where this inhuman tragedy was acted.

In the midst of this dreadful commotion, we find the pestilence
contributing its share to the common work of desolation. In Alexandria
in Egypt, says Dionysius, bishop of that place, “fury and discord raged
to such a degree, that it was more easy to pass from the east to the
remotest provinces of the west, than from one place of Alexandria to
another. The inhabitants had no intercourse but by letters, which were
with the utmost difficulty conveyed from one friend to another. The
port resembled the shores of the Red Sea strewed with the carcases
of the drowned Egyptians: the sea was dyed with blood, and the Nile
choked up with dead bodies. The war was attended with a general famine,
and the famine with a dreadful plague, which daily swept off great
numbers of people, insomuch that there were then in Alexandria fewer
inhabitants, from the age of fourteen to that of eighty, than there
used to be from forty to seventy.” It was not in Egypt alone that this
calamity prevailed. It raged with great violence in Greece, and at Rome
itself; where, for some time, it carried off five thousand persons a
day. Many terrible phenomena of nature took place at the same time.
The sun was overcast with thick clouds, and great darkness took place
for several days, attended with a violent earthquake, and loud claps
of thunder, not in the air, but in the bowels of the earth, which
opened in several places and swallowed up great numbers of people in
their habitations. The sea, swelling beyond measure, broke in upon the
continent, and drowned whole cities.[36]

  [36] Univ. Hist. vol. xvi. pp. 433, 435.

At last the civil commotions were settled by the accession of Claudius
to the empire in 268. He found the Roman force so exhausted, that, when
marching against the Goths, he wrote to the senate in the following
terms: “If I should not be attended with success, you will remember
that I fight after the reign of Gallienus. The whole empire is quite
spent and exhausted, partly by him, and partly by the many tyrants
who, during his reign, usurped the sovereignty, and laid waste our
provinces. We want even shields, swords and spears.” In this miserable
plight, however, he gained a most extraordinary victory; three hundred
thousand of the enemy being killed or taken. But, while Claudius thus
carried on the work of death successfully against the barbarians,
he was attacked from a quarter where he could make no resistance: a
violent plague broke out in his army, and carried off himself and a
vast number of his men.

The dreadful defeat given to the Goths did not long preserve the
tranquillity of the empire. New invasions took place, and new massacres
ensued. At last, on the accession of Dioclesian to the empire, it was
thought proper, on account of the present emergences, to divide such
wide-extended territories into four parts, to be governed by four
emperors of equal authority. By the activity and valour of these,
particularly of one of them, named Galerius, the northern barbarians
were repressed, and the Persians reduced so low, that they were obliged
to yield up a great part of their territories; and it is said that
their country might even have been reduced to a Roman province, had the
emperor so inclined. We know not whether, in his eastern expedition,
the Roman army received any infection, nor do we hear of any plague
breaking out in it; but we are told that Galerius himself died of an
uncommon distemper; an ulcer, attended with mortifications, violent
pains, and the production of an infinite number of vermin, which
devoured and tormented him day and night. This distemper, however,
seems rather to have been a cancer than a pestilential disorder, as
he laboured under it for more than a year. After his death, dreadful
wars continued, both by reason of the incursions of barbarians, and
the contests of those who enjoyed, or wished to enjoy, the empire. The
eastern parts, however, had for some time kept free from pestilential
contagion; of which the christian writers say, that Maximin, who
reigned there, had made his boast; and, being a heathen, ascribed it
to the care he took of preserving the worship of the gods. But, if
this was really the case, he soon found his gods unable to protect
him; for, soon after the accession of Constantine the great, and his
embracing christianity, the dominions of Maximin were afflicted with
famine accompanied with pestilence, and that attended by symptoms of a
most extraordinary nature; particularly ulcers about the eyes, which
rendered multitudes of those who were infected with the distemper
totally blind. The christians did not fail to ascribe this plague to
the sins of Maximin; but it must be observed, that to his other sins
he had added that of involving himself in a violent war, during which
the pestilence broke out, and which probably was one of the causes of
it. We may likewise observe, that if the sins of Maximin brought on the
plague, the piety of Constantine could not keep it off; since we find
that in the year 332, a considerable time after the death of Maximin,
the territories of Constantine were ravaged by a dreadful plague, and
the famine was so severe, that, at Antioch, wheat was sold at four
hundred pieces of silver per bushel. The distemper which put an end to
the life of Maximin himself was indeed so extraordinary, that we may
reasonably excuse those who called it a judgment sent directly from
heaven. His eyes and tongue are said to have putrefied; “an invisible
fire was kindled in his bowels, which, being attended with unrelenting
torments, reduced him in a few days to a perfect skeleton; his whole
body was covered over with a kind of leprosy, and devoured by swarms
of vermin; he could not be prevailed upon to take any nourishment, but
greedily swallowed handfuls of earth, as if he had hoped by that means
to assuage his pains, and allay the hunger with which he was tormented
without intermission.”[37] All this, we are told, was the effect of
poison, which he had swallowed in despair, after being defeated in
battle; but the symptoms are unaccountable.

  [37] Univ. Hist. vol. xvi.

After the death of Constantine, the empire being again parted, civil
dissensions took place; the northern barbarians and Persians renewed
their incursions, and at length the battle of Mursa, between the
emperor Constantius and an usurper named Magnentius, destroyed such
numbers that the empire no more recovered its former strength. From
this time therefore the wars with the barbarians became more and more
violent; and, though frequently overcome, the advantage was ultimately
on their side. In 361, the first year of the emperor Julian, the
pestilence again made its appearance. It was accompanied by many
other grievous calamities: Dreadful earthquakes were felt in every
province; most of the cities in Palestine, Libya, Sicily and Greece,
were overturned. Libanius writes, that not one city in Libya was left
standing, and but one in Greece; that Nice was utterly ruined, and
Constantinople greatly damaged. The sea, in several places, broke in
upon the land, and destroyed whole cities with their inhabitants. At
Alexandria, the sea, retiring during an earthquake, returned again
with such violence, that it drowned several towns and villages in the
neighbourhood. The earthquakes were followed by a famine, and the
famine by a pestilence. It was observed by the christian writers, that
the famine seemed to follow Julian from place to place: and no wonder
that it did so; for he not only had always a large army along with
him, which consumed great quantities of provision, but, attempting to
remedy the evil by fixing the prices of provisions, he rendered it much
worse, as the dealers in corn were thereby tempted to convey it to
other places.[38] Indeed this emperor seems to have been inclined to
produce famines wherever he went; for, on his entering the territories
of the Persians, with whom he was at war, he wasted the country to such
a degree, that he could neither subsist nor return; while the enemy,
imitating his example, destroyed all before him. The consequence was,
that, by the time Julian was killed, the famine raged in the Roman camp
to such a degree, that not a single person could have escaped, had not
the enemy mercifully granted them peace.

  [38] Univ. Hist. vol. xvi.

Notwithstanding this dismal situation, we hear of no plague invading
the camp of the Romans at that time. The wars, however, continued with
great violence; and, in the time of Valentinian, Valens and Gratian,
became worse than ever. The dreadful state of the empire in the time
of Gratian is thus described by St. Jerom: “The whole country, from
Constantinople to the Julian Alps, has been swimming these twenty years
in Roman blood. Scythia, Thrace, Macedon, Dardania, Dacia, Thessaly,
Achaia, both Epiruses, Dalmatia, both Pannonias, are filled with Goths,
Sarmatians, Quadians, Alans, Huns, Vandals, Marcomans, &c. whose
avarice nothing has escaped, whose cruelty has been felt by persons of
all ranks, ages and conditions.” “What evils, (says Gregory Nazianzen)
have we not seen or heard of! Whole countries have been destroyed with
fire and sword; many thousand persons of all ranks and ages have been
inhumanly massacred; the rivers are still dyed with blood, and the
ground covered with heaps of dead bodies.”

In the midst of so great calamities, the pestilence, as an evil of
inferior nature, might in many cases pass unnoticed by the historians
of the times; nevertheless, even during that distracted period, we
find some accounts of it. In 384 we are told of a famine and plague
at Antioch; and, in 407, of one in Palestine, said to be occasioned
by multitudes of grasshoppers, which even obscured the sun, and
turned day into night. After having done incredible mischief, they
were thrown by the wind partly into the Red Sea, and partly into the
Mediterranean; whence being again cast ashore by the waves, they
putrefied, and occasioned a pestilence. Two years after, when Rome
had been first besieged by Alaric the Goth, the city was reduced to
such straits, that human flesh was publicly sold, and some mothers
are said to have devoured their children. This terrible famine was
occasioned by the uncultivated state of the country, which had lain
waste for several years, by reason of the wars, and the ports of Africa
being blocked up by Heraclianus lest an usurper should become emperor;
and thus this loyal admiral, for fear that the people should have a
bad governor, determined rather that there should be no people to be
governed. Notwithstanding this terrible famine, however, we hear of no
pestilential disorder taking place; not even after the taking of the
city by Alaric, when bloodshed and massacre were added to the other
calamities.

All this time the empire, by the incursions of barbarians, by
usurpations, civil wars, and the general licentiousness of the people,
had been in a situation not to be described. The invasion of the Hunns,
a new and more formidable enemy than they had ever experienced, now
completed the ruin of the Romans. The whole western part of the empire
became one continued scene of carnage and desolation. The common
epithet bestowed upon Attila, the king of these barbarians, was, “The
_Scourge_ of GOD, the _Destroyer_ of _Armies_.” As a specimen of his
behaviour, we shall select the account of his taking of Aquileia in
452. That city, “being well fortified, and defended by the flower of
the Roman troops, held out, in spite of his utmost efforts, for three
months; at the end of which it was taken by assault, pillaged for
several days together, and laid in ashes; not a single house being
left standing, nor one person alive that fell into the enemy’s hands.
The cities of Trevigio, Verona, Mantua, Cremona, Brescia and Bergamo,
underwent the same fate; the barbarians raging every where with such
fury as can hardly be expressed or conceived, and putting all to the
sword, without distinction of sex, age, or condition.”[39]

  [39] Univ. Hist. vol. xvi.

Every one must own that this was a very effectual method of preventing
the plague in those cities. It did not, however, prevent that, or some
other diseases, from destroying such numbers of the tyrant’s troops,
that he was for that time prevented from taking Rome itself. From this
time, to the total extinction of the western empire, we do not hear of
any remarkable infection taking place. The barbarians still continued
their wars with one another, while the emperors of Constantinople were
likewise at continual variance with the Persians. At last, in the
year 532, they concluded what they called a _perpetual_ or _eternal_
peace, which lasted _eight years_! Other treaties and truces were
concluded; notwithstanding which, the war was almost continual in the
east; while, by the second conquest of Italy, and the invasion of the
Gothic territories, new desolations overspread the west. Thus, for a
great number of ages, mankind had been preparing themselves for the
dreadful pestilence which was about to ensue. Whatever infection could
be communicated to the air by multitudes of carcases rotting above
ground had been done in an ample manner. Whatever debility could be
communicated to the human frame by famine, exposure to the inclemency
of weather, by fatigue, terror, grief, and every thing that can render
life miserable, had also been communicated by the most powerful
means. There only wanted _something_ to begin the calamity; and this,
whatever it was, took place in the fifteenth year of Justinian. Mr.
Gibbon ascribes the origin of it to locusts; and its universality, to
the general mixture of all nations, and the unrestrained intercourse
they had with one another. “No restraints (says he) were imposed on
the frequent intercourse of the Roman provinces. From Persia to France
the nations were mingled by wars and emigrations; and the pestilential
odour, which lurks for years in a bale of cotton, was imported, by the
abuse of trade, into the most distant regions. Procopius relates, that
it spread always from the sea-coast to the inland countries: the most
sequestered islands and mountains were successively visited; the places
which had escaped the fury of its first passage, were alone exposed to
the contagion of the ensuing year. In time, its malignity was abated
and dispersed; the disease alternately languished and revived; but
it was not till the end of a calamitous period of fifty-two years,
that mankind recovered their health, or the air resumed its pure and
salubrious qualities.”

Thus Mr. Gibbon endeavours to explain the causes of this plague from
an alteration in the salubrity of the atmosphere, without taking into
consideration the dreadful commotions among mankind, above related.
But, now that we have noticed two very general infections, one in
767 B. C. the other 1300 years after, we find them both preceded and
accompanied by wars uncommonly violent and destructive. The great
plague in the time of Justinian is said by Mr. Gibbon to have continued
only fifty-two years; but this we must understand of its first and most
violent attack; for it appears, from the testimonies produced in the
former section, that pestilential disorders, even very violent ones,
continued at intervals for several centuries. Thus, from the year 541
to 593, the space of fifty-two years is included; nevertheless, in the
time of Phocas, who began to reign ten years after, the same calamity
continued; as did also violent wars with the Persians and other
barbarians.

The year 622 is remarkable for the flight of Mahomet from Mecca to
Medina, from which time we may date the rise of the empire of the
Saracens; a people who, for desolation and destruction, were perhaps
never equalled except by the Hunns and Moguls. In 630 the impostor
himself died, after having just united the Arabs or Saracens, and
fitted them for the work in which they were to be employed. Their first
exploit was, to fall upon the empire of Persia, now weakened by its
endless wars with the Romans. This was conquered in two years; after
which they broke into Palestine, and conquered the provinces bordering
upon Syria. In 634 they reduced Syria itself and Egypt. In 636 they
took and plundered Jerusalem. In 642 they conquered the African
provinces, and reduced some of the islands in the Levant. With unabated
fury they proceeded to the east and west; laying siege, in 668, to
Constantinople itself, where they received their first check by the
shipwreck of their fleet, and the defeat of their army. Thus, in the
space of 38 years, the immense tract of country from the eastern part
of Persia to the confines of the Mediterranean Sea, with the northern
coasts of Africa, the whole including a space scarce inferior to the
empire of Alexander the Great, was reduced under subjection to a race
of savage barbarians, who knew only how to plunder, destroy, and reduce
other nations to slavery.

In this manner were the eastern parts of the world prepared for a new
infection, supposing the old one to have been entirely gone off. The
Saracens pursued their good fortune, ravaged and conquered from India
to Spain, and from Spain were proceeding northward through France, to
extend their conquests to the other countries of Europe. But here, in
728, their fury was stopped by Charles Martel, the father of Pepin, and
grandfather of Charles the Great. After a most obstinate and bloody
battle, which lasted seven days, and in which the barbarians lost three
hundred and seventy-five thousand men,[40] they were driven beyond the
Pyrennean mountains, and never after durst enter France. Thus was one
fury stopped, only to give place to another. Charles, as ambitious and
as cruel as the Saracens, having in vain attempted the conquest of
Spain, reduced Italy and Germany; and, having dreadfully massacred the
Saxons, and almost exterminated the Hunns, set up the German Empire,
and was crowned emperor of the West in 800.

  [40] M. Millot places this account among the “exaggerations which
  ought not to have a place in history;” but, as we have no evidence
  for or against the fact, it was thought proper to let it remain as
  related by the historians of those times. It is certain that in those
  days mankind assembled for the purposes of bloodshed and slaughter in
  prodigious numbers; the destruction was commonly in proportion to the
  numbers assembled. The account is not more incredible than that of
  Tamerlane’s filling up the harbour of Smyrna by causing each of his
  soldiers to throw a stone into it. Such an army could have spared the
  number in question.

While the nations were thus deluging the earth with blood, the
pestilence made its appearance in the east, attended with extraordinary
phenomena.[41] Some of these are taken notice of by the Arabian
historians, and others are mentioned by them, concerning which
the Greek histories are silent. In 636, particularly, we hear of
violent storms of hail throughout the Arabian Peninsula, and of Syria
being ravaged by epidemic distempers. It would seem, indeed, that
the plague, during the whole of these horrible periods, had never
been extinguished; for in 671 they tell us that a celebrated Arab,
named _Ziyad_, died of the plague; though neither Greek nor Arabian
historians take notice of any remarkable pestilence as raging at that
time. We are told that this man was attended by no fewer than _an
hundred and fifty_ physicians.[42] “But, _as the decree was sealed_,
and _the thing determined_, they found it impossible to save him.” This
distemper was attended with such an excruciating pain in his right
hand, that the unhappy patient had recourse to a _cadi_, or judge, to
inform him whether he might lawfully cut it off. The judge determined
that it was absolutely unlawful to do so; notwithstanding which,
Ziyad resolved to proceed: but his heart failed him when he saw the
instruments and cauterising irons to be employed in the operation; for
in those times of barbarity and ignorance they knew no other method of
stopping blood but by a hot iron; and therefore some of the physicians
in ancient times, when a limb was to be cut off, ordered the incision
to be made down to the bone with a red hot razor. But, to return to our
subject: In Syria and Mesopotamia swarms of locusts infected the earth
about the year 679; but, as it seems extremely probable that the plague
was never out of the eastern regions, we cannot expect to hear much
of it, unless when extremely violent. That in the time of Constantine
Copronymus seems to have extended over Arabia, as we are told that
the Khalif Yezid, who was cotemporary with Copronymus, died of the
plague. We are also told, that the earthquakes which afflicted the
territories of the Greek emperors extended themselves to the countries
about the Caspian Sea. In those ages indeed the phenomena of nature
appear to have been so extraordinary, that we can scarcely account
them any other than miraculous. Some of these have been described in
the former section, on the authority of the Greek historians: the
Arabians make mention of others similar. They tell us, also, that
once or twice it rained black stones, and that some of these were so
inflammable, that an Arab having attempted to make a fire with one of
them in his tent, it burst out into such a violent flame as consumed
the tent altogether.[43] This rain may be accounted for from the
explosion of a volcano; but how shall we account for the sun himself
losing his light? a phenomenon acknowledged even by Mr. Gibbon; though
that author huddles things together in such a manner as seems totally
inconsistent with the regular chain of events. He tells us, that the
dreadful plague, which broke out in the time of Justinian, was preceded
by comets, and most violent earthquakes; and that these comets were
attended with an extraordinary paleness of the sun. This may be; but
the word _paleness_ cannot apply to the _darkness_ which lasted from
the fourth of August to the first of October, and to which he seems to
allude, though it happened long after the time of Justinian; neither
can it be applied to what I am now about to relate, viz. that in the
year 782, a little after sunrise, the solar light was lost without an
eclipse, and the darkness continued till noon. It is impossible to
read the histories of those times without remembering the words of
our Saviour, that there should be signs in the sun and in the moon,
distress and perplexity of nations, the sea and waves roaring, men’s
hearts failing them for fear, &c. But, however the God of nature might
thus intimate to mankind his displeasure with their proceedings, it
is certain they made no alteration in their conduct. The Saracens,
having conquered immense tracts of country, engaged in civil wars
among themselves; the western nations, after having tried in vain to
destroy each other, at last united in a romantic design of conquering
Palestine from the Infidels; while the Turks, leaving their habitations
about Mount Caucasus, where, like the vultures of Prometheus, they
had for ages remained unseen and unknown, precipitated themselves
upon the Greeks and Saracens, and lastly, as if all hell had broke
loose at once, the Moguls, from the most easterly part of Asia, poured
destruction upon the countries to the west, even as far as Russia and
Poland.

  [41] See Sec. i.

  [42] Modern Univ. Hist. Arabia.

  [43] That such accounts are not to be looked upon as entirely
  fabulous, may be gathered from what is related by Mr. Thomson in
  his travels through Palestine, viz. that on the brink of the lake
  Asphaltites he found numbers of “small _black pebbles_, which are
  soon set on fire by being held in the flame of a candle, and yield a
  smoke intolerably stinking and offensive; but have this remarkable
  property, that by burning they lose nothing of their weight, nor
  suffer any diminution in their bulk. They are capable of taking as
  fine a polish as black marble, and are likewise said to be met with
  of considerable size in the neighbouring mountains.”

All these events took place in a few centuries. In 844 the Turks
quitted Mount Caucasus, and settled in Armenia Major. In 1030 they
fell upon the Saracen empire, now divided among innumerable chieftains
continually at war with each other. Among these was one called the
Sultan of Persia, and another of Babylon. The former being worsted,
called in the Turks to his assistance. They sent him an auxiliary
army of only _three thousand_ men; and from this slender beginning
has arisen the vast empire of the Ottoman Porte. The three thousand
men were commanded by a general called by the Greeks _Tangrolipix_,
and by the Asiatics _Togrul Beg_. Being a man of ability, the Sultan
of Persia, by his assistance, got the better of his adversary; but,
refusing to let the Turks depart, Tangrolipix with his army withdrew
to the desert of Carbonitis, where, being joined by numbers of
discontented Persians, he began to invade the territories of the
Saracens. The Sultan of Persia sent against him an army of twenty
thousand men, whom Tangrolipix surprised and defeated, acquiring at the
same time an immense booty. The fame of his victory, and his wealth,
procured him bands of robbers, thieves, and blackguards, from all the
neighbouring countries; so that he soon found himself at the head of
fifty thousand. Against such a formidable force the Sultan of Persia
marched in person; but happening to lose his life in the engagement by
a fall from his horse, his men threw down their arms and acknowledged
Tangrolipix to be Sultan of Persia.

The new sultan instantly thought of destroying other sultans and
potentates; for which purpose he opened a passage for his countrymen
from Armenia to Persia. The Sultan of Babylon was the first victim;
after which Tangrolipix turned his arms unsuccessfully against the
Arabians, but afterwards more successfully against the Greek emperors.
The first invasion by the Turks took place in 1041; and in four hundred
and twelve years they became absolute masters of the empire. Though
unsuccessful at first against the Saracens, they prevailed greatly
afterwards, and, by the time of the crusades, we find them masters of
Palestine, as well as several other countries formerly conquered by
the Arabs. From the time of their first invasion, in 1041, we may say,
the war never ceased; and there is the greatest reason to suppose that
the Greek empire would have been overthrown in a very short time, had
not the crusaders checked their progress. The immense numbers with
whom the barbarians had now to contend (amounting to no fewer than
seven hundred thousand) threatened with destruction the newly erected
empire of the Turks; and had it not been for the want of unanimity
among the crusaders themselves, and the jealousy of the emperors of
Constantinople, they certainly would have overthrown it. But, as
matters went, all their labour was lost; and they only increased the
general carnage and desolation to an extreme degree. The first crusade
was planned in 1093, published in 1095, and in March 1096 the first
army set out. In 1097 they began their conquests, but soon found it
very difficult to keep them. The Turks being at home, and united, had
many advantages over foreign invaders; which the latter endeavoured
to counteract by drawing continual supplies of fresh men from Europe.
Thus, for several centuries, the western part of Asia was rendered
a scene of bloodshed and desolation. When they had contended for
something more than _two hundred_ years, Jenghiz Khan, the Mogul, seems
to have formed the _noble_ design of destroying the whole human race
at once, excepting only his own immediate followers. His plan was, to
_exterminate_ man, woman and child wherever he went, and to plant the
countries with his own people. It is impossible to do justice to his
exploits. Voltaire, speaking of the irruption of the Moguls, says,
that the people fled every where before them, like wild beasts roused
from their dens by other beasts more savage than themselves. In the
Universal History we are told, that he is supposed to have destroyed
_fourteen millions and an half_ of his fellow creatures. He died in
1227, and left successors worthy of himself. Some of these proceeded
eastward, and some westward. The latter, under the conduct of a
_monster_ named _Hula-ku_, overthrew, in the year 1256, the remains
of the Saracen empire, by the taking of Bagdad. The miserable Khalif,
coming forth to meet his conqueror, was trampled under his horse’s
feet, then sewed up in a sack, dragged through the streets, and thrown
into the river. The Moguls who proceeded eastward invaded China. The
Chinese resisted with innumerable multitudes, and battles were fought
to which those of the present age are mere skirmishes. The soldiers,
overcome with thirst, drank blood instead of water; hundreds of
thousands fell on both sides, while human blood ran in streams for five
or six miles. At last the fury of the Moguls was stopped by the ocean;
for, having attempted the conquest of Japan, their fleet was wrecked,
and an hundred thousand perished. Like other great empires, also,
pretenders to the sovereignty started up, and the whole was parcelled
out into a number of little states, which, of course, ceased to be
formidable.

The decline of the Mogul empire did not restore peace to the world.
The Turks continued their ravages; the western nations continued their
crusades. England, which became a kingdom in 800, had been ravaged
and conquered by the Danes and Normans, and likewise distressed by
civil wars. At last, having emerged from its own difficulties, it
began to inflict upon other nations the miseries itself had endured.
Wales and Scotland became objects of the ambition of Edward I, who had
already signalized his valour in the crusade. The Welsh were totally
subjugated, and the Scots overthrown in the very bloody battle of
Falkirk, where almost the whole force of the country was destroyed. The
Scots, however, were never totally subdued. Robert Bruce retaliated on
the English in the battle of Bannock-burn, where two hundred thousand
English were defeated by thirty thousand Scots. But Robert was not
contented with asserting the liberty of his country. Jealous of his
brother Edward, he sent him with an army to conquer Ireland. We shall
not doubt of his valour, or of the miseries he inflicted, or was
willing to inflict, upon the people among whom he came. In destroying
them he destroyed his own army. They were reduced to the most dreadful
straits by famine, insomuch that they were obliged to feed upon the
most loathsome matters, their own excrements not excepted.

Being now arrived at the beginning of the fourteenth century, we see
that, from Ireland to China, mankind had involved themselves in one
general work of destruction. Besides the wars, famines had been so
frequent, that the eating of one another seemed to be but a common
affair. Indeed the history of mankind would tempt one to believe that
they thought themselves brought into the world for no other purpose but
to destroy each other. As far back as the year 409, in the time of the
wars of the Vandals in Spain, a dreadful famine took place, which, in
410, reduced many to the necessity of feeding upon human flesh; parents
devoured their children, and the wild beasts, being deprived of the
dead bodies which they used to feed upon, but which were at this time
devoured by the living, fell upon the latter, and thus increased the
general destruction. Such of the Romans as fled into strong holds and
fortresses, were in the end obliged to feed upon one another. To these
calamities the pestilence was added, which did not fail to rage in its
usual manner. Famine and pestilence had also ravaged the city of Rome
when besieged by the Goths under Vitiges, and under Totila. In this
last siege the unhappy citizens were reduced to such straits, that they
consumed even the grass which grew near the walls, and were at last
obliged to feed on their own excrements. We do not indeed hear, at this
time, of any particular instances of people feeding upon one another;
though, in such dreadful emergences, it is scarcely to be doubted that
some would have recourse to this terrible expedient in order to allay
their hunger. But in the famines which took place during the ravages of
the Saracens, Turks and Moguls, nothing seems to have been more common.
In 1066 a most grievous famine took place at Alexandria in Egypt, and
throughout the whole country. Three bushels and a half of flour were
sold at eighty dinars, a dog at five, and a cat at three. The Visir,
having waited on the Khalif, left his horse at the palace gate; but,
before he returned, the animal had been carried off and eaten. Three
men were hanged for this theft, and their bodies ordered to be exposed
upon gibbets; but next day they were found picked to the bones, their
flesh having been all cut off and devoured the preceding night. Bodies
of men and women were boiled, and their flesh publicly sold. A violent
plague followed, which swept away the greatest part of the inhabitants.
As the hellish Moguls spread desolation wherever they advanced, so
their retreats were equally formidable. In 1243, having advanced as far
as Aleppo in Syria, they found themselves obliged to retreat, and that
for a very odd reason, viz. that their horses were not well shod. This,
however, did not hinder them from destroying every thing the earth
produced, and stripping every man, nay, every woman, they met, even of
their clothes. The consequence was, a terrible famine, so that people
were fain to sell their children for small pieces of bread.

Such was the conduct of men, from one end of the earth to the other,
during the interval, if any interval there was, between the plague
in the time of Justinian and that of 1346. The pestilence, which had
continually raged in one place or other, now overspread the whole
world. At what time it began to decline we know not; and, indeed, as
the same desolations and massacres continued, if these had any share in
its production, it ought scarcely to have declined at all. That there
was all this time little or no interval, appears from what Dr. Rush
says, vol. iii. p. 165, that between the years 1006 and 1680, that is,
in a period of 674 years, the plague was _fifty-two_ times epidemic all
over Europe. Supposing the intervals between every general infection
then to have been equal, and the plague to have lasted only one year at
a time, it must have recurred once in twelve years. But the intervals
were not equal; for the Doctor tells us that it prevailed _fourteen_
times in the fourteenth century; which gives an interval of less than
seven years; and if the pestilence so frequently overspread the whole
continent, we may be very sure that it never was out of particular
places of it. The Doctor adds, “The state of Europe in this long period
is well known.” We shall also consider that of Asia.

The empire of the Moguls, which had fallen into decay, revived under
Tamerlane; who, following the example of Jenghiz Khan, had the epithet
of the _destroying prince_ bestowed upon him by the Indians, on account
of his behaviour in their country. Building his captives into walls
with stones and lime, pounding them by thousands in large mortars, was
his common practice; while the Turks, proceeding westward, wasted every
thing with fire and sword; the christians all the while continuing
their mad crusades, and when driven from one place endeavouring to
establish themselves in another. At last the Turks and Tartars, or
Moguls, or rather their emperors, happening to quarrel, the battle of
Angora, in Galatia, decided (at the expense of some hundred thousand
lives) the dispute in favour of Tamerlane; but, as his empire ended
with his life, the Turks soon recovered from the blow they had
received; and, by the taking of Constantinople in 1453, put an end to
the terrible commotions which had prevailed in the east for so many
ages. The crusades had also for some time been discontinued, and the
world hath since that time been comparatively in a state of peace.

But, by so much intercourse with the Asiatics, especially with the
countries particularly subject to the plague, all Europe had been so
deeply infected, that the distemper could not but prevail for a long
time, even though it had not been kept up by the almost continual
wars of the Europeans with one another, which was too much the case.
Dr. Sydenham informs us that before his time the plague commonly
visited England once in forty years; but by this we must understand a
very violent infection; for Dr. Rush tells us that plagues prevailed
in London _every year_ from 1593 to 1611, and from 1636 to 1649. The
author of the Journal of the Plague Year (1665) mentions a visitation
in 1656; and Mr. Carey, in the beginning of his account of the plague
of London in 1665, says, that the plague was _almost continually_
among the diseases enumerated in their bills of mortality; so that we
may fairly conclude it to have been _endemic_ in that city. Now let
us see how England had employed itself. Its kings, as well as many of
their subjects, had gone to the holy wars, as they called them, and, by
continuing in that devoted country where most probably the pestilence
first originated, it is impossible to suppose that some of them did not
receive the contagion. Having caught the pestilence in the _holy war_,
they came home to diffuse it among their countrymen, and to keep it up
by _profane wars_, I suppose, both foreign and domestic. Henry VII put
an end to a very long and bloody contest between the houses of York and
Lancaster; but he brought the pestilence along with him, which raged
violently during the fifteenth and sixteenth centuries. A most violent
war, for half a century, on the continent of Europe, and civil wars in
England, would still continue to keep the infection alive from 1600
to 1648, when a general peace was concluded; and from the subsequent
state of tranquillity, probably, after the violent attack in 1665, it
seems to have languished and died in England, as a plant in a soil not
natural to it.

But, though England has since remained in peace, on the continent it
has been otherwise. In the beginning of the eighteenth century, the
heroic madness of Charles XII seemed ready to confound the north, while
the glorious exploits of prince Eugene and the duke of Marlborough
appeared equally confounding to France. In the midst of these grand
atchievments, the pestilence silently claimed its share in the common
work of destruction; carrying off upwards of two thousand in a week for
some time, in 1709, in the city of Dantzick, and, in 1711, twenty-five
out of sixty thousand inhabitants in Copenhagen.

The infection, however, seemed now to be retiring to the place from
whence it originally came. In 1666, or soon after, it seems to have
totally abandoned the island of Britain; with the attack in 1711 it
left the western countries of the continent next to that island; in
1713, 1714 and 1715 we are informed by baron Van Swieten that it
ravaged Austria; in 1721, or soon after, it abandoned France; in 1743
it made its last attack on Messina; and in 1784 we find it confined
to Dalmatia and the eastern territories, where it has so long reigned
without interruption.

From the view then which we have taken of the conduct of the human
race, and the consequences of that conduct, we may reasonably conclude,
that war will produce famine and pestilence, and that after all
violent wars a violent pestilence may be expected, especially if the
contending parties interfere with those nations where it is most
frequent. Another piece of conduct by which mankind expose themselves
to pestilential contagions is, the practice of cooping themselves up
in great cities. Mr. Gibbon, speaking of earthquakes, says, that men,
though always complaining, frequently bring mischief upon themselves.
“The institution of great cities (adds he) which enclose a nation
within the limits of a wall, almost realises the wish of Caligula, that
the Roman people had but one neck. In these disasters (earthquakes) the
architect becomes the enemy of mankind. The hut of a savage, or the
tent of an Arab, is thrown down without injury to the inhabitant; and
the Peruvians had reason to deride the folly of the Spanish conquerors,
who with so much cost and care erected their own sepulchres. The rich
marbles of a palace are dashed on its owner’s head, a whole people
is buried under the ruins of public or private edifices, and the
conflagration is kindled and propagated by innumerable fires necessary
for the subsistence and manufactures of a great city.” In plagues,
great cities are unquestionably as pernicious as in earthquakes; not
indeed by reason of the weight and bulk of the materials, but the
confinement of the people within the sphere of infection, and their
continual exposure to the causes which prepare the body for receiving
it. In fact, it has always been found that plagues begin in cities;
and were it not for the multitudes that continually fly out of them
there can be no doubt that the mortality would be much greater than
it is. The intercourse of many nations with one another, the carrying
from one end of the earth to the other of goods capable of bringing
with them the infection, must also be supposed a very principal cause
of pestilence; but this last will be more fully considered in the next
section. At present we may conclude, that, the pestilential contagion
having originally fallen upon mankind for their sins, it is still kept
alive by the same causes; and, as far as we can conjecture, these sins
are, the propensity to murder and destroy which breaks forth in war;
the vanity, pride and luxury which produces great cities; and the same
vanity, &c. joined with avarice, which gives life to commerce. Add to
all this the neglect of the cultivation of the earth, which ought to be
the principal business of man. In consequence of this neglect, immense
tracts of it are still overrun with woods, covered with stagnant and
noxious waters, or lying in waste and now uninhabitable deserts, fit
only for serpents and the most destructive animals. Thus the very
climate is changed from what it ought to be; the elements become
hostile to man in an extreme degree, and the whole system of nature,
originally designed to give life and happiness to the human race, is,
through their own misconduct, changed into a system of misery, disease
and death.

The account just now given of the ways in which mankind bring upon
themselves the plague, and other diseases almost equally terrible, is
so conformable to the opinions of the learned Dr. Mead, that I shall
conclude this section with a few extracts from his works. Of the
small pox he says, that he supposes this “to be a plague of its own
kind, originally bred in Africa, and more especially in Ethiopia, as
the heat is excessive there; and thence, like the true plague, was
brought into Arabia and Egypt, after the manner above mentioned” (i.
e. by war and merchandise.) “Now (adds he) if any one should wonder
why this contagion was so long confined to its native soil, without
spreading into distant countries, I pray him to consider, that foreign
commerce was much more sparingly carried on in ancient times than
in our days, especially between Mediterranean nations; and likewise
that the ancients seldom or never undertook long voyages by sea, as
we do. And Ludolfus observes, that the Ethiopians in particular were
ignorant of mercantile affairs. Therefore when in process of time the
mutual intercourse of different nations became more frequent by wars,
trade and other causes, this contagious disease was spread far and
wide. But, towards the end of the eleventh century, and beginning of
the twelfth, it gained vast ground by means of the wars waged by a
confederacy of christian powers against the Saracens, for the recovery
of the Holy Land; this being the only visible recompense of their
religious expeditions, which they brought back to their respective
countries.” Of the true plague he says, “It appears, I think, very
plainly, that the plague is a real poison, which, being bred in the
southern parts of the world, is carried by commerce into other parts
of the world, particularly into Turky, where it maintains itself by
a kind of circulation from persons to goods; which is chiefly owing
to the negligence of the people there, who are stupidly careless in
the affair: that, when the constitution of the air happens to favour
infection, it rages there with great violence; that at that time,
more especially, diseased persons give it to one another, and from
them contagious matter is lodged in goods of a soft, loose texture,
which, being packed up and carried into other countries, let out, when
opened, the imprisoned seeds of the contagion, and produce the disease
whenever the air is disposed to give them force; otherwise they may be
dissipated without any considerable ill effects. The air of our climate
is so far from being ever the original of the true plague, that most
probably it never produces those milder infectious distempers, the
small pox and measles. For these diseases were not heard of in Europe
before the Moors had entered Spain; and, as already observed, they were
afterwards propagated and spread through all nations, chiefly by means
of the wars with the Saracens. The sweating sickness was most probably
of foreign original. It began in the army with which king Henry VII
came from France, and landed in Wales; and it has been supposed by some
to have been brought from the famous siege of Rhodes, three or four
years before, as may be collected from one place of what Dr. Keyes says
in his treatise on the disease. We had here the same kind of fever
in 1713, about the month of September, which was called the _Dunkirk
fever_, is being brought by our soldiers from that place. This,
probably, had its original from the plague which broke out at Dantzick
a few years before, and continued some time among the cities of the
north.”

I now take leave, for the present, of this subject, which exhibits
the conduct of mankind in such a disagreeable view. Some, like M.
Millot above quoted, may be apt to suppose that many of the accounts
are exaggerated. But it is evident, that in our days it is impossible
to determine any thing to be a falsehood, said to have happened in
former ages, which is not absolutely contradictory to reason. Every
one of the accounts inserted in this section has found a place in the
works of historians reckoned authentic, particularly in the Universal
History. All who believe the New Testament must certainly believe,
from the words of our Saviour, that extraordinary things were to
happen in the ages subsequent to his appearance. Can we then discredit
the relations of those historians who inform us that extraordinary
things have happened? Modern historians, making their own judgments
the infallible measure of wisdom, and the strength of nations now
existing the ultimate measure of human power, have endeavoured to turn
into ridicule every thing which does not precisely accord with these
two. In this the French are particularly culpable; accounting every
thing to be incredible which exceeds the power of modern France to
accomplish, though they certainly do not know even the extent of this
power. Of such scandalous vanity we have a notable instance in the
works of president Goguet, who positively determines that the walls of
ancient Babylon, the pyramids of Egypt, and all the wonderful works of
Semiramis, Nebuchadnezzar, &c. were not equal to the canal of Languedoc
made by Louis XIV!



SECTION III.

  _Of Disease in general.--The nature of the Plague as a Disease
  considered.--Of Contagion.--Whether the Plague is really Contagious
  or not.--Medical History of the Distemper.--Inquiry into its
  Immediate Causes, and whether an approaching Plague is indicated by
  any visible Signs._


Hitherto we have considered the origin of the plague entirely in
a moral point of view. We have seen, that, in conformity to the
general opinion of mankind, it may reasonably be supposed to have
been inflicted upon mankind, the Jews particularly, for their
transgressions; that, having been once introduced, it has been
perpetuated, and spread from nation to nation, and that in proportion
to the degree of immorality of a certain kind prevailing through the
world. From this it is naturally to be inferred, that, were the human
race to live at peace with one another, to disperse themselves over
the face of the earth for the purpose of improving it by cultivation,
and were they to be contented with what the produce of each country
affords, there would be no plague among them. But we know that such
a reformation is not to be expected, and we must take the world as we
find it. The question then is, By what means shall individuals secure
themselves from being destroyed by a plague which shall happen to
invade any country; or how shall a person, already infected with it, be
restored to health? For this purpose let us begin with considering the
nature of disease in general, and of the plague particularly.

As to disease in general, physicians have differed very considerably
in their definitions; and, though many have been given, few seem to be
unexceptionable. That of Dr. Fordyce seems to be among the clearest
and most expressive. “Disease (says he) is such an alteration in the
chemical properties of the fluids or solids, or of their organization,
or of the action of the moving powers, as produces an inability or
difficulty of performing the functions of the whole or any part of the
system, or pain, or preternatural evacuation.” But as this definition,
however just, cannot be easily understood by such as are unaccustomed
to medical language, I shall attempt the following explanation of the
animal economy, and the diseases to which it is subject.

1. By nature our bodies are formed of certain solid and fluid parts,
operating upon one another in a manner of which we know but little.
Anatomists have described the structure of the human body and its
parts in a certain degree, but have always found themselves lost in an
inconceivable minuteness of texture. The whole structure of the human
body, visible and invisible, is called its ORGANIZATION.

2. This organized body is acted upon by certain powers residing in the
atmosphere, by which it becomes endowed with LIFE.

3. The operation of those powers upon a well organized body constitutes
that agreeable and vigorous state which we call HEALTH.

4. The operation of any other power, substituted in place of the
natural one, even upon a body perfectly organized, produces a state
very different from health; commonly attended with some uneasy
sensations, and which is called DISEASE. I say it is _commonly_
attended with uneasiness, but not always; for many persons within a few
hours, nay, a few minutes, of their death, have imagined themselves
quite recovered and well. To illustrate the meaning of what is said
of the substitution of any power instead of the natural one: It is
natural for man to breathe air of a certain quality; and while he does
so he continues in health; but let him breathe the vapour of burning
charcoal, or of fermenting liquor, mixed in considerable quantity with
the air to which he has been accustomed, and he will very soon find
himself diseased. Many other kinds of elastic fluids may be substituted
instead of the vapour just mentioned, all of which will in a short time
produce a disease in the most healthy man. The state of a diseased body
being very different from that of a sound one, the appearances are
consequently very different. The various appearances of disease in the
human body are called _symptoms_ of that disease, from a Greek word
signifying _appearance_.[44]

  [44] “_Symptom_ (says Dr. Fordyce) is the Greek name for
  _appearance_:” but, from the strict etymology of the word, it
  ought rather to be translated _accident_. The universal consent of
  physicians, however, has applied it to every appearance produced in
  the human body by any distemper whatever.

5. A disease proves mortal only by the DISORGANIZATION of the body. By
disorganization I mean any considerable alteration in the structure of
the body, visible or invisible. The truth of this will appear from a
consideration of the method by which animals may be recovered, after
being to appearance dead by breathing the vapour of charcoal, or fixed
air in any other form, viz. by plunging them in cold water. In a cave
in Italy a continual stream of this kind of air issues from the ground.
It rises but a small way, so that a man may safely enter, because his
head is above the vapour; but, if he brings a small dog with him, the
animal, in consequence of breathing the pernicious fluid, falls down
as if dead, and would very soon die if left there. By throwing it into
a lake in the neighbourhood, (cold water of any kind would answer as
well) it recovers. In the dissection of some unfortunate people,
who have been killed by breathing this pernicious fume, a manifest
disorganization has been observed, viz. a rarefaction of the blood, and
too great dilation, or even rupture, of the small vessels.

6. A disease cannot always be cured by removing the cause which
brought it on: it is necessary also to repair the injury done to
the organization. This is exemplified in the case of the dog just
mentioned. Taking him out of the vapour is not sufficient for his
recovery, because the organization of the body is injured; the cold
water by contracting the vessels repairs the injury, and the cure
is completed. To the entire preservation of this organization it is
probably owing, that people have frequently recovered after being
thought dead for a long time.[45]

  [45] Dr. Anthony Fothergill, in his prize dissertation upon the
  suspension of vital action, quotes some experiments of Dr. Kite,
  in which he was able to restore to life animals that had been
  immersed in water for eight, ten or twelve minutes, though he
  acknowledges that this operation, though performed with great
  attention, often failed; while other animals, that had been longer
  immersed, recovered spontaneously. He further adds, that if it be
  not attempted before the convulsions of the animal cease, which
  on an average of many experiments happens in about eleven minutes
  and a half, it will not be sufficient to renew the vital motions.
  But, “among the human species (says Dr. Fothergill) there are not
  wanting well authenticated instances of spontaneous recovery at
  an incomparably longer interval, and after every external mark of
  life had disappeared. Such is the latent energy of the heart, that
  it sometimes, after remaining several hours quiescent, renews on
  a sudden the secret springs of life, surmounts the barriers of
  the resisting blood, and restores circulation with all the other
  functions. Hence the unexpected recoveries from death-like syncope
  brought on by sudden terror, or great effusions of blood, even after
  the funeral obsequies have been prepared. Hence some persons have
  accidentally been brought to life, even after interment, by the rude
  motion produced in sacrilegious attempts to wrest rings or bracelets
  from the apparently dead body.”

  Several surprising instances of the recovery of persons supposed to
  be dead, even of the plague, are given by Fabricius Hildanus; to
  one of which Dr. Fothergill seems to allude in the above quotation.
  Hildanus relates, that in the year 1357, when the plague raged
  violently at Cologne, a certain noble lady, by name _Reichmuth
  Adoleh_, being seized with the disease, was thought to have died,
  and was buried accordingly. Her husband, out of affection, would not
  take off her wedding ring, which she happened to have on her finger.
  The undertakers being acquainted with this circumstance, next night
  came to the church where she was buried, opened the sepulchre, and
  prepared to take off the ring; when to their utter astonishment she
  began to raise herself up in the coffin. Struck with consternation
  they fled in the utmost haste, leaving to the fortunate lady the
  lantern with which they lighted themselves to the church, and by
  means of which she now found out where she was, and after being
  come to herself, returned to her own house. Here being known by her
  voice, and the ring she wore, she found admittance, and by means of
  a generous diet gradually regained her health; bringing her husband
  afterwards three children, and surviving the accident many years.

  A second instance no less remarkable is of a woman of the name of
  _Nicolle Lentille_, who, being supposed dead of the plague, had been
  thrown into a pit with a great number of the bodies of others, dead
  of the same distemper. After lying there a whole night, she came to
  herself in the morning, but neither knew at first where she was, nor,
  when she did, could she find any means of escaping, or extricating
  herself from the heap of dead bodies with which she was oppressed.
  Being at a distance from any house, her cries were of no avail, and,
  in the mean time, having taken no nourishment for four days, she was
  so tormented with hunger that she eat part of the cloth which covered
  her face. At last, after remaining twenty-four hours in this dreadful
  situation, the pit being opened to bury some other person, she
  exerted her utmost endeavours in calling for assistance, and at last
  was heard by those who stood round. Being taken up and brought home,
  she presently recovered, and lived several years after.

  A third example is given by our author of one who, being carried to
  a church to be buried, had his face previously sprinkled with holy
  water by a priest. But this was no sooner done than he shuddered and
  opened his eyes in a fright; on which he was carried home, recovered,
  and lived eight years after. Other examples might be brought, but
  these are sufficient to show what dreadful accidents may ensue from
  early burials, and how cautious people ought to be in consigning
  their friends and relations to the dust from whence they were taken.

7. When the organization of the body is injured, the action of the
natural powers themselves occasions uneasiness, and increases the
disease. The cure then is, to substitute instead of the natural
power, as far as possible, the action of some other power till the
organization is restored; after which the natural power must be again
allowed to act, or a disease of another kind will take place. This
may be exemplified in a consumption of the lungs; where, that part
being very much disorganized, pure air renders the disease worse; and
the sick are relieved by mixing with the common atmosphere such kinds
of air or vapour as would prove pernicious to people in health. But,
supposing this method to be successful, and the consumption to be
entirely removed, it is plain that the use of the pure atmosphere must
be resumed, or the impure air would bring on a disease in the same
manner as on a healthy person.

8. The body is wasted in the natural operations of life; part of
it passing off with the vapour of the breath, part by insensible
perspiration, &c. Hence it naturally tends to disorganization and
death, unless the waste be repaired.

9. This natural waste of the body is repaired, and health kept up, by
the food and drink taken into the stomach.

10. Hence arises another set of diseases; for as the reparation of the
waste, just mentioned, depends on the proper action of the stomach upon
the food, and the assimilation of the latter with the substance of
the body, it is plain that this operation depends both on the proper
quality of the food, and the sound state of the stomach itself.

11. The body is composed of solids and fluids of different kinds,
every one of which is subject to diseases peculiar to itself; but, by
reason of the connexion of the parts of the body with one another,
it is impossible that any one can be very much disordered without
affecting all the rest. As the bond of connexion, however, is in many
cases totally invisible to us, surprising instances frequently occur
of one part being affected in consequence of an injury done to another
very distant from it. This connexion between all parts of the body is
called SYMPATHY. Dr. Gardiner of Edinburgh, in his observations on
the animal economy, &c. says, that “the stomach is the principal seat
of many of the most remarkable sympathetic affections which happen in
valetudinary states of the body. Every disorder accompanied with severe
pain affects the stomach, whilst this viscus affects not only in its
diseased state every part of the system, but at other times the effects
of healthful stimuli applied to it are instantly communicated to the
rest of the body, as when we take food, wine, or medicine.” Dr. Darwin
in his Zoonomia informs us that the stomach is said to sympathize with
almost every part of the body; but Dr. Moore, in his medical sketches,
tells us that the _heart_ possesses a greater share of sympathy than
any other part in the body, and next to it the stomach.[46]

  [46] Dr. Gardiner, in his observations above quoted, gives the
  following curious anecdote. “An unmarried lady, of a healthy
  constitution, has such a peculiarity in the structure of her nerves,
  that, though she can, in general, bear strong odours as well as
  most people, yet she cannot suffer a rose to be in her bosom, or
  to hold it in her hand a few minutes, without becoming faint, and
  having an inclination to vomit. Conserve of roses, rose-water, and
  similar articles made from roses, have more powerful effects upon
  her, and usually excite vomiting. Going into a room where any of her
  companions are washing with rose-water, never fails to produce this
  effect; nor does she recover of her indisposition in less than two
  hours.”

12. The solid parts of the body are the bones, the muscles, brain
and nerves; the fluids are, the blood, and others produced from it.
The bones are known to every one; the muscles are the fleshy parts
throughout the whole body; and the nerves are a kind of cords seemingly
originating from the brain, and from thence accompanying the blood
vessels through all parts of the body.

13. Much has been disputed about what is to be accounted the primary
part of the body, on which all the rest depend; and one class of
disputants have arranged themselves on the side of the _blood_, and
the other on that of the _nerves_. The dispute is like one about
the beginning of a circle. It cannot be decided, because the blood
cannot act without nerves, nor the nerves without blood. I speak of
the human body, being aware that in some animals the position may be
controverted. The following is a concise state of the matter.

14. All the blood in the body passes through the heart; which has four
cavities; two called _ventricles_, and two _auricles_. These, from
their position in the body, are called the _right_ and _left_. The
right ventricle communicates with the right auricle, as does also the
left ventricle with the left auricle; but there is no communication
between the right ventricle and the left, nor between the right
auricle and the left. Through these cavities all the blood passes to
every part of the body, and returns from every part; but, as in the
former case, we are here at a great loss where to begin its motion;
for this is precisely to find the beginning of a circle. As we must
begin somewhere, however, we shall do so with the right ventricle of
the heart. This receives the blood returning from all parts of the
body, and propels it into the right ventricle; not the whole quantity
at once, for it cannot contain one half of it; but by degrees. The
auricle contracts as soon as it is full; and in the time that the
auricle fills, the ventricle contracts, so that it may be empty, and
ready to receive the blood from the auricle. By the contraction of
the right ventricle the blood is driven into the pulmonary artery,
and passes into the lungs. Here the artery branches into an infinite
number of small vessels much finer than hairs; and these again,
uniting into larger trunks, form at last the pulmonary vein, which
brings back the blood to the heart. The pulmonary vein is inserted
into the left auricle of the heart, which, as soon as it is filled
with blood, contracts, and expels the blood from it into the left
ventricle. From the left ventricle issues a large artery called the
_aorta_, which by its branches supplies the whole body with the vital
fluid. In all parts of the body the arteries divide themselves into
innumerable small branches, which terminate in veins equally small
as in the lungs; but it has been disputed whether the arteries and
veins actually join each other in the form of vessels, or whether the
arteries deposit the blood in small cells, from which the veins suck
it up. The dispute is of no consequence, nor can it be absolutely
decided, on account of the exceeding smallness of the vessels; though
the microscopical observations are rather favourable to the opinion
of a continuation of vessels. The veins from all parts of the body
unite into larger vessels, and these again uniting with one another,
form at last one very large vein called the vena cava, which opens
into the right auricle of the heart, from which the circulation goes
on as already described. The two ventricles of the heart, and all the
veins throughout the body, are furnished with a kind of valves, which
allow the blood to proceed in the way of circulation, but prevent its
returning in a contrary direction.

15. The lungs, through which all the blood in the body passes, receive
likewise the air which we draw in every time we breathe. They consist
of two large bodies called _lobes_; from their situation called the
right and left. The air is conveyed into them by the wind-pipe, called
also the _trachea_, and the _aspera arteria_. On entering the cavity of
the breast, the wind-pipe divides into two large branches called the
_bronchiæ_; one of which goes to the right and the other to the left
lobe of the lungs. By the further division and subdivision of these
vessels the lungs are filled with an innumerable multitude of little
tubes, terminating in exceedingly minute bladders or cells, which
are the final receptacles of the air sucked in when we breathe. Each
of these cells is surrounded with a kind of network of blood-vessels
exceedingly small, and consisting of very thin membranes; so that, in
passing through the lungs, the blood is exposed as much as possible to
the action of the air.

16. It is a matter of great importance to find out what is the use
of this exposure of the blood; and great disputes have taken place
concerning it. In former times it was supposed that the blood received
from the air a _vital spirit_, without which it would have been totally
incapable of performing its offices in the body. Later physiologists
endeavoured to explode this notion. Dr. Hales particularly, by shewing
that the circulation of the blood through the lungs might be continued
by inflating and contracting them alternately by the fumes of burning
brimstone, endeavoured to prove that the use of the air was only to
give the lungs an opportunity of dilating and contracting alternately,
by which means principally he thought the circulation might be carried
on. This continued to be the most common hypothesis as late as the time
of Dr. Huxham. It was however thought also that by the compression of
the air the blood was altered in its texture, its bulk, &c. Accordingly
Dr. Huxham tells us in the preface to his treatise on air and epidemic
diseases, that “air fit for respiration ought neither to be too hot,
nor very cold; for the use of the inspired air is to temperate the
blood, which would otherwise grow too hot, and putrefy, as is evident
from the experiment of the most excellent Boerhaave made in a hot
house; for, if the air is more hot, or even equally hot, as the blood
of any animal, it certainly soon dies.”[47]

  [47] This certainly does not hold good if we suppose the heat of the
  atmosphere to be indicated by a thermometer; for we are assured that
  animals can live in a heat much superior to that which raises the
  mercury to 97.

17. The modern discoveries in the composition of air, have tended
greatly to elucidate the use of this fluid in the lungs, and its action
on the blood in respiration. Dr. Priestly first determined it to be
what he terms a _phlogistic process_, i. e. a process by which the
parts of the blood no longer proper to be retained among the rest, or
at least some of them, are carried off. That _something_ is carried off
either from the lungs themselves, or from the blood circulating through
them, is evident; for the air which is taken into the lungs in a dry
state, comes out of them extremely moist, and loaded with vapour. An
essential change is also made in the nature of the air itself; for it
now assumes in a great measure the nature of what has been called fixed
air, or the fume of charcoal, or fermenting liquor, and thus becomes
unfit for being breathed a second time. This change is made by the
addition of some terrestrial substance to the pure atmosphere, which
the latter volatilizes and carries along with it.[48]

  [48] The discoveries of modern chemists have determined that the
  aerial fluid, termed _fixed air_ or _carbonic acid_, and which is
  nearly the same with the vapour arising from fermenting liquor, and
  is also largely contained in the fume of burning charcoal, is not
  a simple but a compound substance; one part consisting of the pure
  part of the atmosphere, or _oxygene_, the other of real charcoal. The
  proportions, according to M. Chaptal, are 12,0288 parts of charcoal
  to 56,687 of oxygen.

18. But, whatever may be _carried off_ from the blood, during its
passage through the lungs, something is certainly _added_ to it,
for the blood in the pulmonary artery is of a dark red, but when it
has undergone the action of the air in the lungs, and returns by
the pulmonary vein, it is then of a bright scarlet, which colour it
retains through all the arteries of the body, but loses it on its
return through the veins. This scarlet colour is communicated to blood
in all cases when exposed to the air; and Dr. Priestley has observed
that it is acted upon by the air even through a bladder; much more
then must it be so through those very thin membranes which form the
coats of the fine pulmonary vessels. What this subtile matter is which
the blood receives, shall be afterwards inquired into; at present it
is sufficient to take notice that it is absolutely necessary, for the
purposes of life, that the blood should pass through the lungs: for,
as Dr. Huxham observes, “we see neither nutrition, nor the motion of
the muscles, performed by any blood that hath not passed through
the lungs; this is observable from the coronary arteries[49] to the
ultimate ramifications of the aorta.” As the previous circulation
of the blood through the lungs therefore is absolutely necessary to
the growth and life of the body, and as the blood certainly receives
_something_ from the air, we must account this a proof, and no
inconsiderable one, that the air contains a _vital spirit_, which it
imparts to the blood in the lungs. But, before we proceed farther on
this subject, it is proper to take some notice of

  [49] The name of the vessels by which the heart itself is supplied
  with blood. These come from the aorta by the circuitous way of the
  lungs.

19. _The nerves._ These, which constitute such a remarkable and
important part of the human body, are white cords, of a soft pulpy
substance, defended by a tough skin which goes along with them as far
as they can be traced. All the nerves either originate from the brain,
or terminate in it. The former doctrine hath been generally adopted,
and in conformity to that doctrine the following account of the nerves
is laid down. The brain is enclosed in the cavity of the scull, but not
without the intervention of two membranes, called the _dura_ and _pia
mater_, to prevent injury from the hard bones, as well as for other
purposes. The brain is divided into two lobes, the right and left. It
is composed of two different kinds of substance, the outermost called
the cortical, the innermost the medullary substance; the latter seems
composed of fine fibres. The whole of the medullary part of the brain
terminates in a substance called the _cerebellum_, very much resembling
the brain, but smaller. The cerebellum terminates in another substance
resembling the medullary part of the brain, called the _medulla
oblongata_. The cerebellum lies in the back part of the head, and
the medulla oblongata under it. The latter terminates in the spinal
marrow, extending from the lower and back part of the head to the lower
extremity of the back bone, and is enclosed in the hollow of that bone.
The nerves proceed from these four substances, viz. the brain, the
cerebellum, the medulla oblongata, and spinal marrow. As they pass to
all parts of the body they accompany the arteries, dividing with them
into innumerable small branches; but they do not return with the veins;
so that they seem not to contain any fluid which goes and comes, or
which circulates like the blood. The nervous fluid, if any such there
be, seems to move constantly one way, either to the brain or from it.

20. Hitherto we have noticed only things which are evident to our
senses, and which the industry of anatomists has abundantly evinced;
but now our subject renders it necessary to step aside a little into
the obscure regions of theory and conjecture. The muscles, as we have
formerly said, are the fleshy parts of the body; and by them all the
motions of the body are performed. The flesh is distributed into
distinct portions, each of which is enclosed in a membrane belonging
to itself. Each of these portions is a muscle, and each muscle has
a branch of an artery and the branch of a nerve belonging to it. On
both these the action of the muscle depends; for, if we cut the nerve
belonging to a muscle, it immediately loses all power of action; and
if we cut the artery which accompanies the nerve, it does the same. As
therefore the blood is found to receive _something_ from the air, and
as it loses this when passing through the arteries, and as the nerves
lose their power when the communication with the blood is cut off, it
seems extremely probable, that what is imbibed by the blood in the
lungs is taken up by the fine ramifications of the nerves, and is no
other than the immediate principle of life and sensation. Thus we will
establish a doctrine directly opposite to that commonly received; for,
instead of supposing that the nerves originate from the brain, we are
now led to suppose that they terminate in it. Instead of supposing that
the sensations originate in the brain, we will be led to suppose that
every sensation originates in the organ appointed for that sensation.
Thus we are conscious that our _eyes_, not our _brain_, are the parts
of our body which immediately perceive the light; our fingers, or
any other parts of the body, _feel_ what is applied to them; and of
consequence we have reason to believe that the _animal spirits_,
_nervous fluid_, or whatever we please to call it, proceed from the
surface of the body inwards to the brain, not outwards from the brain
to the surface of the body. The brain itself seems to resemble a large
collection or reservoir of water, in which the sensations, like so many
small streams from every part of the body, unite, and in which our
intellectual faculties reside in a manner totally inexplicable by us.
Thus far it seemed necessary to theorise, in order to form some idea,
however obscured, of the connexion between the nerves and our sensitive
and intellectual, or, if we please to call them so, our _spiritual_
faculties.

21. In consequence of this very intimate connexion between the blood
and nerves, it is easy to see that any injury done to the one may
very greatly affect the other; and that a very slight, nay, to us
imperceptible, change in the organization of either, may produce the
most grievous, and even incurable disorders throughout the whole body,
or in any particular organ. Let us now consider a little farther the
blood-vessels.

22. It hath been a question, whether in the structure of these vessels
nature hath observed an exact proportion. For instance, if the blood
passes by a kind of starts through four cavities, as we are assured
that it does, it seems natural to suppose that these four should be
exactly equal. This, however, hath been denied; and some, from its
accommodating the human frame to their theory, have fancied that
they saw the use of such disproportionate work. Dr. Huxham expresses
himself in the following words: “Nor doth the air only refrigerate the
blood, but, by preventing its too great ebullition, and condensing
it, hinders it from bursting the vessels. This indeed is of exceeding
great importance, if, with the very learned _Helvetius_, we suppose
the capacity of the right ventricle of the heart to be greater than
that of the left, and that the pulmonary arteries are larger than the
correspondent veins; for it thence follows, that the blood ought to
be considerably condensed by the inspired air, that an equal quantity
of blood may be received, in one and the same time, by the pulmonary
veins and left ventricle of the heart, that is thrown off from the
right ventricle, and through the more capacious pulmonary arteries.
This indeed many deny, asserting quite the contrary. It is necessary,
however, that the aorta should receive as much blood from the left
ventricle of the heart, as is thrown off from the right ventricle
through the pulmonary artery; and that in the very same and equal
time, or a fatal deluge would soon overwhelm the lungs, because the
contraction of each ventricle is made at one and the same time; we
always find therefore the aorta and pulmonary artery, in a natural
state, equal on this account; also the capacity of the ventricles ought
to be equal, that they may receive, in one and the same space of time,
equal quantities of blood,” &c.

If any thing farther is necessary upon this subject, we may still
observe, that if the blood were at all condensed by the air, it would
be so unequally, because the air is at some times much colder than at
others; and thus the disproportion of the cavities of the heart to
one another could not fail of producing the most disagreeable if not
fatal effects. We often see what terrible consequences ensue upon the
enlargement of any part of an artery near the heart; and these would,
sometimes at least, be felt by every individual.[50]

  [50] But there is a still more egregious blunder, and this the more
  surprising as it has been very general among physiologists, viz.
  that when an artery branches into two the capacity of the branches
  taken together is greater than that of the trunk. This would make the
  whole arterial system one continued _aneurism_,[51] and, instead of
  promoting the circulation of the blood, would in the most effectual
  manner prevent it. In what manner an error so extraordinary in its
  nature could pass the mathematical physicians of the last century,
  I cannot imagine; but certain it is, that, in the year 1780 or
  1781, the Edinburgh College were schooled on this subject by one of
  their own students named _John Theodore Vander Kemp_, a Dutchman.
  This gentleman found, by accurate mensuration, that when an artery
  divides, if the diameters of the two branches are made the two
  shorter sides of a right-angled triangle, the diameter of the trunk
  will be the hypothenuse; and thus, as the areas of circles are to one
  another in proportion to the squares of their diameters, the sum of
  the areas of the two branches will be equal to the area of the trunk.
  On looking into Blumenbach’s physiology, I find the same remark.

  [51] An aneurism is a preternatural enlargement of an artery. The
  blood stagnates in that place, and at length eats through the flesh
  and skin.

It is true, indeed, that this objection will in some degree hold, even
though we suppose all the cavities of the heart to be equal, and the
capacities of the blood vessels to be perfectly uniform throughout the
whole body. For, if we suppose the blood to be at all condensed in the
lungs by the coldness of the atmosphere, it must undoubtedly follow,
that while passing from them it occupies less space than before it
arrives at them. Hence the pulmonary vein, the left auricle of the
heart, the left ventricle, the aorta, and all the rest of the arteries
for a considerable way, must be comparatively empty, even though
they receive as much fluid as fills the vena cava, right auricle and
ventricle of the heart, and pulmonary artery. The equality which ought
to prevail in the system, and which indeed cannot be dispensed with,
can only take place in those remoter branches of the arteries in which
the blood has reassumed its former state of dilation or rarefaction.

23. If we consider this matter attentively, we shall find it not a
little mysterious. Every time we breathe out the air we have sucked
into our lungs, a considerable quantity of moist vapour is breathed
out along with it; but it has been proved by undeniable experiments
that the emission of aqueous vapour from any substance cools it in
proportion to the quantity of vapour emitted. Every breath we draw,
then, cools the lungs, and consequently the blood, to a certain degree,
and, as the number of times that we breathe in a day is exceedingly
great, the cold produced by the evaporation ought to be in proportion.
But we see that, notwithstanding all this cooling, whether we breathe
cold air or hot air, the temperature of the body remains still the
same. The air then, though constantly carrying off the heat of the
body, does not cool it in the least by its action on the lungs. The
only possible way of solving this apparent contradiction is, by
supposing that the air, when acting upon the blood in the lungs, leaves
precisely as much heat as it carries off, and therefore, though we
breathe ever so long, we cannot by this means become either hotter or
colder.

24. To illustrate this subject, we might now enter into an inquiry
concerning the origin and cause of animal heat; but this will be
touched upon hereafter. We shall here only take notice that the heat of
the body is almost universally allowed to proceed from the lungs. It
has likewise been demonstrated, that the air does in fact contain an
incredible quantity of heat, even when it appears to us to be extremely
cold. A certain proportion of this heat is separated from it every time
we breathe; and if, either by the mixture of other fluids with the air
we breathe, or by any change in the organization of the body itself,
a greater or smaller proportion of heat should be communicated to the
blood, disease must ensue.

25. To sum up then what has been said concerning the blood and nerves:
The whole mass of fluid passes from the right side of the heart to the
lungs. In the lungs it receives from the air something[52] necessary
to the functions of life and sensation, and purifies itself from
those matters which might prove pernicious. From the lungs it passes
to the left side of the heart, and thence through the whole body. In
its passage through the body, it is accompanied with nerves, which,
taking up from the arterial blood that _vital spirit_ received from
the air, convey it to all the organs of motion, of sensation, and to
the brain, where the whole powers of perception being united form our
_intellectual faculties_, and, as far as our senses can perceive,
the human spirit itself. The blood, thus deprived of its spirit, is
collected from all parts of the body by the veins, and returned to the
right side of the heart, from whence it is again sent to the lungs,
and the process carried on as before. This hypothesis concerning the
peculiar function of the nerves I first inserted in the Encyclopædia
Britannica, second edition, under the article BLOOD, in the year 1778.
It has been since continued in the third Scots edition, and from thence
into the Irish and American editions.

  [52] It seems now to be proved beyond a doubt that this
  _something_ so long unknown is that fluid called by Dr. Priestley
  _dephlogisticated air_, and by Lavoisier _oxygen_.

26. It has already been observed, that the body is subjected to a
continual waste. One source of this waste is the breath, by which a
considerable part passes off in vapour. A great quantity also passes
off by the pores of the skin; frequently in a perceptible liquid called
_sweat_, but oftener in an invisible vapour from all parts of the body,
called _insensible perspiration_. The latter has been thought to be the
great source of waste to the human body; and it is certain, that if any
person in health be weighed when he rises in the morning, he will be
found considerably lighter than when he went to bed. The loss of weight
in this case proceeds not only from the pores of the skin, but from the
lungs; but though physicians have made a general allowance for both
these, I have not heard of any experiment by which we can determine
how much passes off by the one, and how much by the other, nor indeed
does it appear easy to make such an experiment. Galen plainly overlooks
the perspiration from the lungs entirely. “This excrementitious vapour
(says he) is expelled through small orifices, which the Greeks call
pores, dispersed all over the body, and especially over the skin,
partly by sweat, and partly by insensible perspiration, which escapes
the sight, and is known to few.” Sanctorius, and the succeeding
writers, have classed both together indiscriminately; allowing the
discharge to be so great, that if eight pounds of aliment be taken in,
five of them pass off in this manner. In a system of anatomy, published
at Edinburgh in 1791, the author says, that the discharge by the skin
“is even much larger than this (the discharge from the lungs we may
suppose) since it not only throws off a quantity of the aliment, but
likewise what is added to the blood by inhalation, which, entering
often in a very considerable quantity, is thus again expelled.” The
same author likewise says, that the “perspirable matter from the skin
is principally water,” and that it issues in such quantity as to be
seen in subterraneous caverns evidently flying off from the surface of
the body like a dense vapour. But other physiologists, particularly Dr.
Blumenbach, inform us, that the matter of insensible perspiration is
quite similar to the discharge from the lungs, particularly containing
a great quantity of fixed air. The same account is given in Chaptal’s
chemistry, on the authority of Messrs. Milly and Fouquet. This may
be looked upon as a valuable discovery, especially in conjunction
with that related by Drs. Beddoes and Girtanner, viz. that the flesh
of animals contains a quantity of oxygen. Dr. Girtanner obtained a
quantity of this air from the raw flesh of animals, and says that it
may be repeatedly obtained by exposing the flesh to the atmosphere, and
distilling with a heat of 60 or 70 degrees of Reaumur’s thermometer
(something below that of boiling water.) Hence it is natural to
conclude, that, as the discharge from the lungs purifies the blood
from its useless parts, so does the insensible discharge from the skin
purify the solid parts from those particles which are no longer useful.
The probability of this also becomes greater by considering, that in
diseases, when the quantity of matter to be thrown off is very great,
the skin becomes foul, the teeth furred with black sordes, &c. all
which disappear as soon as the quantity of the offensive particles is
reduced to its natural standard. As to any considerable quantity of
aqueous vapour being discharged this way, unless in case of sweat, it
does not seem probable; for in such a case our clothes would always
be moist; and in the night time the accumulation of moisture would
certainly be perceptible. The sweat is entirely of a different nature
from the insensible perspiration, and blood and even _sand_ has been
known to issue through the skin along with it. (_See the Anatomical
System above quoted._)

27. This very considerable waste of the body is repaired by the aliment
taken into the stomach. In the mouth it is mixed with a considerable
quantity of the liquid called _saliva_, and in the stomach with another
called the _gastric juice_, with which that organ always abounds. From
the stomach it passes into the intestines, where it is mixed with other
two fluids; one called the _pancreatic juice_, the other the _bile_.
This last is of a yellow colour, and is sometimes produced in enormous
quantities, insomuch that Dr. Wade, in his account of the fevers in
Bengal, mentions some patients who have voided by stool half a gallon
of bilious matter in one day.

28. In the stomach principally the aliment undergoes a certain change
called _digestion_, by which it becomes capable of being converted into
the substance of the body. Much has been inquired and disputed, to no
purpose, about the nature of this change, and how it is effected. One
party has declared for _attrition_; a second for _putrefaction_; a
third for _heat_; a fourth have supposed that our meat was digested by
_chewing_; as if, like the lobster, people had teeth in their stomach!
and, lastly, some learned moderns, after much pains and trouble, have
found out that it is digested by _solution_. Dr. Moore has summed up
the discoveries concerning digestion in the following words: “The
food, being previously divided and blended with the saliva and air by
mastication, (chewing) is swallowed, and meets in the stomach with
the gastric juice, whose dissolving power, assisted by the natural
heat of the place, is the principal agent in digestion. The process is
completed by the pancreatic juice and bile, the nutritious parts of the
food being by this process converted into chyle for the support of the
body, and the grosser parts thrown out.”[53]

  [53] Moore’s Medical Sketches.

29. The inside of the stomach and intestines are full of the mouths of
innumerable small vessels, which continually suck up from the aliment,
as it passes downwards, the finer parts, in form of a white liquid,
called _chyle_; and from the whiteness of their colour the vessels have
the name of _lacteals_, from the Latin word _lac_, milk. After passing
through the substance of the stomach and intestines, and running along
the membrane called the _mesentery_, to which the intestines are
attached, the lacteals unite in a large reservoir called the _thoracic
duct_; and this again opens into a large vein on the left side, called
the _subclavian_, which conveys the blood from half the upper part of
the body; soon after terminating in the vena cava, by which the chyle
is conveyed to the heart, thence to the lungs, and so on in the common
course of circulation. The conversion of the chyle into blood is called
the process of _sanguification_.

30. The blood, thus formed out of the aliment we swallow, is not one
uniform fluid like water, but composed of three distinct substances;
one, which gives it the red colour, and seems to be composed of little
round globules; another, quite colourless, but of a viscid nature,
and which very soon coagulates, called the _lymph_; and a third, of a
yellowish colour, and retaining its fluidity much longer, called the
_serum_. A remarkable property of this last fluid is, that air can act
through it upon the blood; for Dr. Priestly found that a portion of
black blood assumed a bright, florid colour from the air, even though
covered with serum an inch deep. When blood is drawn, the red globules
are detained by the lymph which coagulates, and both together form
the red mass called _crassamentum_; the serum remaining fluid, and
retaining its name.

31. Besides these fluids, the blood either invisibly contains, or
is capable of being converted into, a great many others; for all
the fluids in the body are separated from it, and all of them, the
bile only excepted, from the arterial blood, before it has lost that
portion of its spirit which it imbibes from the air. When a fluid is
to be secreted, sometimes it is done only by an infinity of small
vessels branching off from the arteries, and depositing the liquids
which pass through them in particular places; and such are the fluids
which moisten the inside of the body, and which are carried off by the
breath, or by sweat. But this separation does not by any means hinder
the artery from terminating in its usual way in a vein, for in no case
is the whole substance of the blood converted into any other liquid;
all of them appear to be contained in it. But the greatest number of
fluids are separated by means of certain substances called _glands_.
These are small round or oval shaped bodies; each of them enclosed in
a membrane or skin which separates it from the other parts, and each
furnished with a small tube called the _excretory duct_, through which
the liquor separated in the gland passes to its place of destination.
Each gland has also an artery and nerve, and a vein to bring back the
blood after it has parted with the fluid intended to be separated. The
bile is separated in the liver from the blood of a large vein called
the _vena portarum_, formed by the union of some of the veins of the
intestines and mesentery. This vein branches out through the liver like
an artery, terminating in other veins, which at last bring back the
blood to the heart.

32. As the human body is thus furnished with an apparatus for
separating and carrying off, it is also furnished with one for
absorbing or taking in. All the inward parts of the body are moist;
and the moisture is furnished by the small vessels above described,
and which separate part of the lymph from the blood. By such continual
separation the cavities of the belly, breast, brain, &c. would soon
be filled with liquid, were not some means provided for carrying it
off as fast as it is formed. The means in question are a set of small
vessels called _lymphatics_. These “arise from the internal surface of
the breast, belly, and every cavity of the body; they also overspread
the whole external surface of the body, and large lymphatic vessels
are usually found close to the large blood vessels of the extremities,
besides those small superficial ones which lie above the muscles in the
cellular membrane (the fat or rather the membrane containing it.) The
large viscera generally have two sets of lymphatics, one lying on the
surface of the viscus, and the other accompanying the blood vessels
belonging to it. The faculty of absorption, though refused to the
lymphatics, was ascribed by many anatomists to common veins, and this
opinion continued to prevail in some degree, until Hunter and Monro
totally overturned it, exploding at the same time the notion that any
of the lymphatics are continuations of arteries, and establishing,
beyond a doubt, that all are absorbent vessels.”[54] All the lymphatics
terminate in the thoracic duct; so that the liquid separated by the
_exhalant arteries_ (so the vessels are termed by which that fluid is
separated) is again mixed with the blood, and again performs the same
offices.

  [54] Moore’s Medical Sketches.

We have now taken a review of the several parts of the human body,
slight and superficial indeed, but such as the limits of this work
would allow, and sufficient to furnish to those entirely unacquainted
with medical matters some general ideas on the subject. We have seen
that the body, in general, consists principally of four great parts,
the blood-vessels, the lymphatic vessels, the nerves, and the muscles.
Besides these we enumerate the glands and membranes; the former being
nearly allied to the blood-vessels, the latter _apparently_ to the
nerves. The bones, having no concern with our present inquiry, are not
taken notice of. The stomach and intestines, being principally composed
of muscular fibres, nerves, and blood-vessels, must be considered
as belonging to these departments. Each of these large divisions
has obtained the name of _system_; and even the subdivision of the
blood-vessels into arteries and veins. Thus the arteries of the body,
taken collectively, are called the _arterial system_; the veins the
_venous system_; the brain and nerves the _nervous system_; the muscles
the _muscular system_; the lymphatics the _lymphatic system_; and the
glands the _glandular system_; &c. These appellations have been given
for the sake of distinctness and perspicuity, but they have had a bad
tendency. Insignificant disputes have arisen concerning the superiority
of one system to the other, and which is to be accounted the _primum
mobile_ of the body. By observing also the _general_ structure of the
body in a more full and ample manner than that of the parts which
compose it, physicians have been apt to generalize too much in their
theories, and to fancy that from a few obvious laws they might be able
to explain the phenomena of disease in almost every possible variety.
To illustrate this, let us take the blood for an example. This to sight
appears an homogeneous fluid; and Boerhaave and others have ascribed
diseases to some defect or bad quality of the blood. But this fluid
consists of three parts, each, as far as we can perceive, essentially
distinct from the other; viz. the lymph, serum, and red globules.
As each of these happens to be diseased, the cure must be different;
or if two happen to be diseased, the medicines must still be varied.
But, besides these general diseases arising from what, like the blood,
is common to the whole body, each component part of the body has an
arterial system, a venous system, a nervous and lymphatic system, &c.
belonging to itself; all of which, though dependent on the body at
large, have yet laws of their own, in consequence of which any one of
them may be considerably diseased without much affecting the general
system; and this constitutes what is called _local_ disease. Again:
The parts of the body are so connected with one another, that the
disease of one may show itself in another; or it may affect the whole
body in such a manner as to produce a general disease; though Dr.
Rush considers this last, at least from injuries of the viscera, as a
rare occurrence;[55] but we certainly know that general diseases are
very often followed by evident diseases of particular organs; and in
these cases it is impossible to say whether the general disease did
not begin, though imperceptible to us, in that very organ in which
we suppose it to terminate when the local disease was come to such
an height as to be evident to our senses. In some cases it is plain
that local injuries will bring on most violent diseases of the whole
system. Thus a local inflammation of the end of one of the fingers,
by physicians called a _paronychia_, has been known to induce a most
violent fever, nay, even to occasion death. These violent symptoms
end as soon as the suppuration is completed; so that, were it not for
the excessive pain of the inflammation, we might be apt to suppose
that the fever terminated in the suppuration, whereas it evidently
was occasioned by the local disease, or the tendency of the part to
suppurate; the pain and inflammation being necessary preliminaries.
Again: When an intermittent fever is said to terminate, or to be
followed, by a hardness of the liver, we do not certainly know whether
an original disease of the liver might not have been the cause of
the intermittent. From a consideration of all these things, viz. the
extreme diversity of parts which compose the human body, the ultimate
invisibility of the structure of each, the incomprehensible manner
in which they are united, the equally incomprehensible dependence
they have upon one another in some cases, and independence in others,
the numerous laws by which they are governed, and which must be very
much unknown to us, the invisible and incomprehensible nature of the
powers which act upon them, &c. &c. I say, when we consider all these
things, the boldest theorist must be humbled when he attempts to
account for the phenomena of disease in any one instance. The excessive
difficulty in which we are involved is beautifully described by Dr.
Ferriar when speaking of hysterics; and obstacles equally insuperable
by our theories will undoubtedly be met with in any other distemper.
“We are ignorant (says he) by what laws the body possesses a power of
representing the most hazardous disorders, without incurring danger;
of counterfeiting the greatest derangement in the circulating system,
without materially altering its movements; of producing madness,
conscious of its extravagances; and of increasing the acuteness of
sensation by oppressing the common sensorium. In hysterical affections
all these appearances are excited, which are incompatible with the
reasonings of every system-maker who has yet endeavoured to explain the
inexplicable. Nature, as if in ridicule of the attempts to unmask her,
has, in this class of diseases, reconciled contradictions, and realized
improbabilities, with a mysterious versatility, which inspires the true
philosopher with diffidence, and reduces the systematic to despair.”

  [55] Medical Inquiries and Observations, vol. iv, p. 133.

Notwithstanding all these difficulties, however, physicians have
theorised, and that with such animosity, as if all the arcana of nature
had been laid open to every professor who thought proper to invent or
new-model a system; though the constant succession of theories might
certainly have shown them the vanity of such attempts. Some of these we
must now consider.

Medical theorists have exerted their greatest abilities in explaining
the nature of those general diseases affecting the whole body,
denominated _fevers_; and which are likewise called _acute_ diseases,
from the violence with which they sometimes attack, and the rapidity
with which they run through their course. Dr. Fordyce says, that
fever will sometimes kill in _five minutes_ from the first sensation
of uneasiness. Ancient physicians have described a number of fevers,
which they supposed to be of different species, and accordingly have
distinguished by different names. Modern system-makers have added
to the number; so that a bare detail of the names which they have
given to their divisions and subdivisions, would constitute a very
formidable catalogue; but the latest practitioners are decidedly of
opinion that there is but one kind of fever, varying itself according
to circumstances. Dr. Rush declares himself of this opinion in
the most express and positive terms. “There is (says he) but one
fever. However different the predisposing, remote or exciting causes
may be, ... still, I repeat, there can be but one fever.... Thus
fire is an unit, whether it be produced by friction, percussion,
electricity, fermentation, or by a piece of wood or coal in a state of
inflammation.”[56]

  [56] Vol. iv, p. 133.

“I have said that there is but one fever. Of course I do not admit
of its artificial division into genera and species; a disease which
so frequently changes its form and place, should never have been
designated, like plants and animals, by unchangeable characters....
Much mischief has been done by nosological arrangements of diseases.
They erect imaginary boundaries between things which are of an
homogeneous nature.... They gratify indolence in a physician, by fixing
his attention upon the name of a disease, and thereby leading him to
neglect the varying state of the system, &c.”[57]

  [57] Ibid. p. 149.

So much then having been said and written upon the disease in question,
one might be apt to suppose that the nature of fever would have
been thoroughly investigated, and its causes explained in the most
satisfactory manner, long before this time. Instead of this, however,
we find it still like a word which every body uses, and nobody
understands. Dr. Fordyce, who has lately written a treatise on the
subject, endeavours to prove that there is not any single symptom from
the existence of which we can certainly determine the presence of this
disease. “Fever (says he) has obtained its name in Greek, Latin, Arabic
and Persian, principally from the idea of heat: _pur_, in Greek fire;
_febris_ in Latin, from _fervere_, to burn,” &c. This idea, he goes
on to demonstrate, is erroneous; as the body of a feverish patient
frequently sinks the thermometer below the natural standard; while the
patient sometimes finds himself cold when the thermometer shows him
to be really hot, and hot while the same instrument shows him to be
cold. Neither is cold, followed by heat, a certain indication of the
presence of fever, as many fevers begin without any previous sensation
of cold. Frequency of the pulse also is no certain sign; and having
discussed this last symptom he concludes thus. “If we examine the
restlessness, anxiety, state of the tongue, head-ach, or any other of
the symptoms which often take place in fever, we shall find that they
also may be present when there is no fever, and absent in a patient
afflicted with this disease; and therefore we cannot allow that there
is any pathognomic symptom of fever.”[58] Dr. Rush declines giving
any definition of fever;[59] but, with all due deference to these two
very experienced physicians, we must account such extreme scepticism
altogether erroneous. If fever cannot be defined, it cannot be
described; for a _definition_ is no other than a short _description_.
If again there be no single symptom by which the presence of fever
can be known, it is impossible that there can be any _combination_
by which it can be known, any more than we can form an unit by any
combination of cyphers. In fact Dr. Fordyce himself is at last obliged
to acknowledge that there is a certain symptom with which fever
_generally_ begins; and, by his insisting upon it in various parts of
the work, we must certainly be induced to suppose that it was by this
sign principally that he determined whether his patients had a fever
or not. “The first appearance (says he) which generally takes place is
uneasiness and restlessness; a general uneasiness, the patient feeling
himself ill, but incapable of fixing on any particular part of the
body. This uneasiness affects the mind at the same time. Perhaps in
this case it is the mind that is first affected.... Along with this
uneasiness there is a restlessness, the patient wishing to change his
place or posture frequently; the mind cannot likewise rest upon one
object; it often wanders from one to another subject. At the same time
there is a feel of weariness which resists the disposition in the
patient to change his place and posture, and resists the disposition
of the mind to alter the object of its attention, rendering the wish
for such changes ineffectual. With these arises an actual inability of
exerting the muscular powers, or performing any of the functions of the
body; and also an actual inability of exercising the great faculties of
the mind, the powers of perception, memory, arrangement of ideas, and
of the judgment, in the same degree that they existed in health. The
degree in which these take place is extremely different in the attacks
of different fevers; but these appearances are _very rarely_ absent,
although indeed they may also happen in other diseases.”

  [58] A _Pathognomic_ symptom is one which being present _certainly_
  indicates the presence of a disease, and being absent, the contrary.

  [59] Vol. iv, p. 123.

Dr. Rush accounts the lassitude with which fever begins, one of the
transient phenomena of it; and this with other phenomena he calls
_symptoms_. Such as are more permanent and fixed, and which by other
writers have been reckoned different species, he calls _states_; and of
these he enumerates forty. Such as have any relation to the plague are
as follow.

I. The MALIGNANT state, known by attacking frequently without a
chilly fit, is attended with coma, a depressed, slow or intermitting
pulse, and sometimes by a natural temperature or coldness of the
skin.... This depressed state of fever more frequently when left
to itself terminates in petechiæ, buboes, carbuncles, abscesses and
mortifications, according as the serum, lymph, or red blood, is effused
in the viscera or external parts of the body.

2. The SYNOCHA, or common inflammatory state; attacking suddenly with
chills, succeeded by a quick, frequent and tense pulse, great heat,
thirst, and pains in the bones, joints, breast or sides.

3. The BILIOUS state of fever; known by a full, quick and tense pulse,
or by a quick, full and round pulse without tension, and by a discharge
of green, dark coloured or black bile from the stomach and bowels. This
state sometimes assumes the form of an hectic; the patient feels no
pain in his head, has a tolerable appetite, and is even able to sit up
and do business.

4. The TYPHUS state; known by a weak and frequent pulse, a disposition
to sleep, a torpor of the alimentary canal, tremors of the hands, a
dry tongue, and, in some instances, a diarrhœa. Sometimes it assumes
symptoms of synocha on the eleventh, fourteenth, and even twentieth
days. The common name of this state is the _nervous_ fever.

5. Intermissions, or the INTERMITTING and REMITTING states, occur
most distinctly and universally in those which partake of the bilious
diathesis.

6. The SWEATING state occurs not only in the plague, but in the yellow
fever, small pox, pleurisy, rheumatism, hectic and intermitting states.

7. The FAINTING state; occurring in the plague, yellow fever, small
pox, and some states of pleurisy.

8. The BURNING state. This is attended not only with an intolerable
sensation of heat in the bowels, but with a burning sensation excited
in those who touch the patient’s skin. It occurs mostly in the
remitting fevers of Asia.

9. The CHILLY state differs from a common chilly fit by continuing four
or five days, and to such a degree that the patient frequently cannot
bear his arms out of bed. The coldness is most obstinate in the hands
and feet. A coolness only of the skin attends in some cases, which is
frequently mistaken for an absence of fever.

10. The INTESTINAL state; including the cholera morbus, diarrhœa, and
cholic.

11, 12, 13, 14, 15. The APOPLECTIC, PHRENETIC, PARALYTIC, LETHARGIC and
VERTIGINOUS states.

16. The ERUPTIVE state; including the small pox, measles, and other
exanthemata of Dr. Cullen.

17. The HÆMORRHAGIC state; known by fluxes of blood from various parts
of the body.

18. The CONVULSIVE or SPASMODIC state. Convulsions are frequently
attendant on the malignant state of fever.

19. The CUTANEOUS state; attended with various eruptions on the skin,
particularly _petechiæ_.

These include the most remarkable varieties described by physicians
as different species. From the subsequent account of the symptoms of
the plague, it will appear that this single distemper monopolises,
as it were, the symptoms, at least the most dangerous and terrible,
belonging to them all. Those nosologists therefore who suppose the
states of fever above described to be different species, instead of
saying that the plague belongs to one kind of fever, ought to say
that it is a complication of a great many different kinds. But here a
question arises: Do all the varieties of fever just now described, or
do all the other fevers described by different authors, include all the
different modes by which the plague makes its attack? If so, then we
know that the plague really partakes of the nature of fever, or may be
accounted the highest degree of it. This is the opinion of Dr. Rush;
for in his 4th vol. p. 153, he considers the different inflammatory
states of fever, according to their strength, in the following order.
1. The plague. 2. The yellow fever. 3. The natural small pox. 4. The
malignant sore throat, &c. To this I can have but one objection,
and to me it appears insuperable; viz. that the plague frequently
destroys without any symptom of fever; and, if so, we must certainly
account it a distemper of another kind. To decide this matter, let
us compare the symptoms of the most violent fever with what happens
in times of violent pestilence. We can scarce imagine a fever more
powerful than that which destroys in five minutes, and the following
is the description of it from Dr. Fordyce. “When the first attack of
fever has been fatal, it has been classed among sudden deaths, and
all of these have been very erroneously called apoplexy, or syncopy
(_fainting_.).... When the attack is fatal, it sometimes kills in five
minutes, sometimes it requires half an hour, seldom longer than that
time. While the patient is yet sensible, violent head-ach with a great
sense of a chilliness takes place, the extremities become very cold,
and perfectly insensible; there is great prostration of strength,
so that the patient is incapable of supporting himself in an erect
posture; he becomes pale, his skin is of a dirty brown, and he is soon
insensible to external objects; the eyes are half-open, and the cornea
somewhat contracted. If the patient goes off very soon, the pulse is
diminished, and at last lost, without any frequency taking place, but
if it be longer before he dies, the pulse becomes excessively small
and frequent; all the appearances of life gradually subside, and
the patient is carried off. Of this the author has seen instances,
sometimes at the first attack, oftener in the returns of the disease,
although very few.”

This no doubt is very terrible, and no plague whatever can exceed it.
Indeed, when _death_ is the termination, it signifies little what the
_disease_ is called. But the question is not whether fever or plague is
the most dreadful, but whether they are the same. Now, from the above
description, it is plain that fever never kills without some warning.
In the present instance, head-ach and chilliness give a certain, though
short, warning of the ensuing catastrophe; but, in violent plagues, Dr.
Sydenham informs us, that people have been suddenly destroyed as if by
lightning. Dr. Guthrie assures us that in the last plague at Moscow
he has seen soldiers drop down suddenly as if they had been struck
by lightning, or by a musket ball; yet some of these recovered by
bleeding and proper management; but it is certainly not unreasonable
to suppose that many, who were not thus taken care of, perished. Dr.
Hodges speaks of the contagion of the plague in the most energetic
terms. He says, “it is so rare, subtile, volatile and fine, that it
insinuates into, and resides in, the very pores and interstices of
the aerial particles. It is said to be of a poisonous nature also,
from its similitude to the nature of a poison, so that they seem to
differ in degree only; for the deadly quality of a pestilence vastly
exceeds either the arsenical minerals, the most poisonous animals or
insects, or the killing vegetables; nay, the pestilence seems to be
a composition of all the other poisons together, as well as in its
fatal efficacies to excel them.... The contagion of the plague is
more active than lightning, and in the twinkling of an eye carries to
a distance putrefaction, mortification and death. As for the manner
whereby it kills, its approaches are generally so secret, that persons
seized with it seem to be fallen into an ambuscade or a snare, of which
there seems to be no suspicion.... In the plague of 1665, as in many
others, people frequently died without any symptoms of horror, thirst,
or concomitant fever. A woman, who was the only one left alive of a
family, and in her own opinion in perfect health, perceived upon her
breast the pestilential spots, which she looked upon to be the fatal
_tokens_; and in a very short space died, without feeling any other
disorder, or forerunner of death.... A youth of a good constitution,
after he had found himself suddenly marked with the tokens, believed at
first that they were not the genuine marks, because he found himself
so well; yet he was dead in less than four hours, as his physician had
prognosticated. A fever, however, did for the most part show itself,
and was always of the worst kind. Sometimes it seemed to resemble a
quoridian, sometimes a tertian; there never was a total cessation, but
every exacerbation was worse than before.” In like manner the author
of the Journal of the Plague Year informs us that many, supposing
themselves, and supposed by others, to be in good health, would
suddenly find themselves seized with great sickness, crawl to a bench,
and instantly expire. “Many (says Dr. Hodges) in the middle of their
employ, with their friends and other engagements, would suddenly fall
into profound, and often deadly sleeps.”

It is needless to multiply examples: the above are sufficient to
show that the plague, when in its most violent state, kills suddenly
and imperceptibly, and that like the bite of a vampire,[60] without
producing any sensible disorder. In a state somewhat inferior, it
excites the most malignant fevers; in one still inferior it produces
fevers of a milder nature, and so on until we find it so mild, that
those infected with it are not even confined to their bed. In all
this inquiry, however, we find the secrecy and invisibility of the
pestilence, so often mentioned in scripture, still confirmed. Other
distempers may “waste openly at noon-day,” but this always “walks in
darkness.”

  [60] The vampire is a kind of bat, of a very large size, met with
  in some parts of South America and in the East Indies. This vile
  creature delights in human blood, and often attacks people in the
  night time in the most insidious manner. A late traveller relates
  that at Surinam he was bit by one of them, which sucked so much of
  his blood that in the morning he found himself exceedingly weak and
  faint. He felt no pain, nor was sensible of the injury in any other
  way. The vampire commonly attacks the great toe, making a wound
  so exceedingly small that the person is not awaked by it; it then
  sucks till gorged with blood, and, lest the patient should awake, it
  keeps fanning him all the while with its large wings, the coolness
  of which, in that hot climate, promotes sleep. In this manner some
  are said to have been destroyed. Captain Cook relates an humourous
  anecdote of one of his sailors, who being ashore at New Holland, and
  having wandered a little way into the woods, returned in a fright,
  crying out that he had seen _the devil_! Being asked in what shape
  Satan had appeared, he answered, “He was about the size of a _one
  gallon keg_, and very like it; and if I had not been _afear’d_, I
  might have touched him.” It was a vampire. The man, notwithstanding
  his fright, had not exaggerated its magnitude. People, though
  mistaken and terrified, are not to be disbelieved in every part of
  their relation.

In one of the inferior stages of this distemper the body is affected
with those eruptions named buboes and carbuncles. Dr. Patrick Russel,
in his treatise on the plague at Aleppo, divides the symptoms of the
distemper into six classes. In the first there were no eruptions,
and all the patients of this class died. In the second, and all the
rest, there were buboes and carbuncles. But, in the latter of these
especially, it is worthy of remark, that they appear neither as
a suppuration, nor as a common mortification, but like the eschar
formed by a caustic, which can scarcely be cut by a knife. This
appearance is not to be met with in any other disease. In many there
are mortifications of various parts of the body, but all these are
soft, and seemingly corruptions of the flesh. When a person dies of any
ordinary distemper, the flesh soon corrupts and dissolves, but there
is no example of its turning to a hard eschar like that made by a hot
iron, or the caustic with which issues are made. This shews not merely
a cessation of life, but the operation of some very active power in the
body, like fire, tending to destroy the texture of it entirely, and to
reduce it to a cinder. This power seems also to operate internally in
the fleshy parts; for when the bodies of those were opened who died
with the _tokens_, as they are called by Dr. Hodges, upon them, the
mortification was always found much larger inwardly than it appeared
to be on the outside. The tokens themselves are by Dr. Hodges called
“minute distinct _biasts_, which had their origin from within, and
rose up in little pyramidal protuberances, sometimes as small as pins’
heads, at others as large as a silver penny; having the pestilential
poison chiefly collected at their bases,” &c.

That the plague was by the ancients reckoned a disease of a nature
different from all others, appears from Galen, as quoted by Deusingius.
“What is called the _pestilence_ is most properly remarked by Galen
not to be a _genus_ of any known disease. For whatever diseases and
symptoms are associated with the plague, truly and properly so called,
the same are wont to be called _pestilential_ diseases; of which indeed
there are an innumerable multitude, and these not always nor every
where the same.”[61]

  [61] Non esse certi morbi genus, id quod _pestilens_ vocatur,
  rectissime notatum a Galeno est (3 Epid. comm. 3. t. 20.) quicunque
  enim morbi ac symptomata consociantur pesti veræ proprieque diclæ,
  ijdem _morbi pestilentes_ apellari consuevere, quorum equidem
  innumerabilis existit cohors, ac non semper et ubivis eadem.
  (_Deusing. de Peste_, _Sect._ iii.)

In like manner Diemerbroeck, as quoted by Allen, gives his opinion,
that “The plague is something different from a fever, and a fever is
only a symptom of it, as I have _very often_ observed; and therefore
some very ill define the plague by a fever, since a fever does not
essentially belong to it.... A pestilential fever, the _companion
of the plague_, is not occasioned by a pestilential venom, but by
the mediation of putrefaction; that is, it is not produced because
the humours are infected with the pestilent venom, but because the
heart, being irritated, overwhelmed and much weakened by the pestilent
venom, can neither duly digest and rarefy, nor govern and sufficiently
discharge the infected humours; which for this reason putrefy and
acquire a preternatural heat, and so excite a fever; which by reason
of the foresaid secondary cause, is different and distinct from the
plague, and a symptom of it. This is confirmed both by the maxims and
authority of the ancients and moderns, as well as by practice, and
evident examples.”

Thus it appears, both by fair reasoning by induction from facts, and
from the authority of the greatest physicians, that the plague is
certainly a disease by itself, and entirely distinct from all others.
Hence it follows, that, though we could investigate the causes of
fever in their utmost extent, we might still be ignorant of the true
plague. That nothing, however, may be omitted, let us now consider what
physicians have advanced on this subject, and what progress they have
made in ascertaining the sources from whence so many direful calamities
are derived.

In an inquiry of this kind, or indeed concerning any cause whatever,
it is plain that the nature of the effect must be first understood.
Fever then being an _effect_, we must begin with investigating its
_nature_. But fever itself is only manifest by certain changes in the
human body. Before we can investigate the nature of fever, therefore,
we must investigate the human body, and that in a manner very different
from what we did before. We must now consider the sources of life; in
what manner the vital principle acts upon the body, and by what means
its motions can be disturbed, or how they may be rectified when once
disordered, &c. &c.

The systems of medicine before the time of Boerhaave are now so
generally exploded, that it is needless to take any notice of them;
and the reputation of Boerhaave himself in this way seems to be almost
expiring. His doctrines, nevertheless, merit some attention, because
he takes into account a principle overlooked by succeeding theorists,
viz. the _cohesion_ of the parts of the body. That he did so is
evident, from his having written upon the diseases of a _weak and
lax_ fibre, and the diseases of a _strong and rigid_ fibre. In other
respects he followed in a great measure the mechanical physicians of
the former century. He therefore took but little notice of the nervous
system, as being less subject, or indeed to appearance not at all
subject, to the known laws of mechanics. The blood was more manageable.
The microscopical discoveries of Lewenhoeck furnished an excellent
foundation for his system. This celebrated observer had discovered, or
fancied he had discovered, that the red part of the blood is composed
of globules. Inaccurate indeed these globules must have been, since
each of them was composed of six; four touching one another in the
middle, with one above, and one below, thus [Inline illustration].
The serum was said to be composed of single globules, and by this
attenuation it was supposed that the fluid, instead of red, appeared
of a _yellow_ colour. Still, however, this was insufficient. Each of
the yellow globules was _discovered_ (either by fancied observations
or by conjecture, it matters not which) to be composed of six others,
which, singly taken, might constitute the lymph or some other fluid;
and thus, like the number of the Beast, we might go on by sixes to the
end of the chapter, and solve all the phenomena of nature. In justice
to the microscopists, however, it must be observed, that some of
them have given a much less fanciful account of the structure of the
blood than Lewenhoeck. Mr. Hewson found it composed of vesicles, or
small bladder-like substances, with a black spot in the middle. These
vesicles dissolved in pure water, but kept their original form, which
he says was as flat as a shilling, when a small portion of neutral salt
was added to the fluid. The solid particles he supposed to be produced
by the lymphatic system; the black particles by the spleen.

The supposed observations of Lewenhoeck were of considerable use to
Boerhaave in the forming of his system of medicine, though they seem
not to have accorded very well with his doctrine of lentor or viscidity
in the blood. But, let this be as it will, having laid it down as the
foundation of his theory, that the diseases of the body proceeded from
too great a laxity of the fibres, or from too great a rigidity of them,
and a great many from this _lentor_, his practice was accordingly
directed to such medicines as he imagined would remove these supposed
causes of disease. As the lentor of the blood was one of his favourite
suppositions, he was therefore perpetually at war with this imaginary
enemy, and dealt very much in saponaceous medicines with a view to
break it down. But here it is evident that this great man was mistaken,
even though we should allow the existence of lentor as much as he
pleased. The viscidity, _lentor_, or any other state of the blood, is
an _effect_ of something. It is part of that state into which the body
is brought by the disease. The efforts of the physician therefore ought
to be against that which produces the lentor; for, unless this be done,
the cause of the disease must perpetually counteract the medicines by
producing new lentor as fast as they destroy it; and besides, must have
greatly the advantage of the physician, by being already in possession
of the whole mass of blood, while the medicines can only enter it very
gradually, and that by the stomach and lacteals, instead of being
instantly mixed with it, and exerting their power immediately upon the
fluid itself.

But besides this mistake, which is common to other systems, Boerhaave’s
lentor has been denied, and that upon such strong grounds that it is
now universally exploded. Another system quickly succeeded, in which
every thing was managed by the nerves. This was introduced by Hoffman,
adopted, and perhaps improved, by Dr. Cullen, under whose auspices
it acquired such a degree of celebrity, that for a long time it was
dangerous to write or speak against it; and the person who had the
audacity to do so underwent a kind of medical proscription from the
Edinburgh College and all its students. According to this celebrated
theorist, the brain is that part of the body first formed in the
embryo; it may be seen with nerves proceeding; from it long before the
heart or any blood-vessel belonging to it is visible. Hence we are to
conclude that this part is necessary to the existence of every other
part of the body, though it doth not appear that they are essentially
necessary to its existence. The superiority of the nerves to all other
parts being thus established, the Doctor undertook to prove that
all other parts of the body were formed from them; that the body is
nourished immediately from them, and in short that the whole body is
in such subjection to the nervous system, that, except for the mere
purpose of distending the vessels, we can scarcely know for what end
the blood exists; since the nerves can alter its consistence, or that
of any of the fluids secreted from it, by a mere affection of that
system, without any thing either added to or taken from the vital fluid.

Thus we were compelled to believe that all diseases at their first
origin are affections of the nervous system, from whence they are
propagated through the whole body. The Cullenian practice in acute
diseases, of which the plague is the most violent, was built upon a
maxim of Hoffman: “Atonia gigoit spasmos:” _Atony produces spasms_. In
explaining the nature of typhus fever, therefore, with which he classes
the plague, the Doctor supposed that the contagion acted first upon
the nervous system, by producing therein a debility. The immediate
effect of this debility is a _spasm_, or preternatural contraction of
the capillary vessels, or extremely small arteries. Hence the blood
finds some difficulty in circulating, and the patient is seized with
shivering, and has a sense of cold. When this has continued for some
time the system begins to _re-act_ against its enemy; the spasm is
resolved, and, the reaction of the system continuing, the action of the
heart and arteries is augmented, and the body becomes warmer.

Thus the coldness, shivering, and consequent heat, which constitute
the first attack of fever, are very plausibly explained; but in the
mode of cure this learned physician fell into the same mistake with Dr.
Boerhaave; for though spasm is undoubtedly, even according to himself,
an _effect_, he directs his medicines entirely against it, as if it
were a _cause_. Thus, forgetting what he had just before advanced,
that the spasm is occasioned by debility, he recommended the most
debilitating medicines and regimen to cure people already too much
debilitated; and to such practice his enemies alledged that many fell
victims. The theory and practice, however, still kept its ground; and
as great numbers of students were every year bred up in the belief of
it at Edinburgh College, who carried the principles of their teacher to
all parts of the world, it bade fair for becoming universal. But, in
the midst of this eclat, the whole system received such a rude shock
from the doctrines of _John Brown_, though at that time not even M. D.
as it hath not yet recovered.

Though the author of the new system contended, as much as Dr. Cullen,
for the supremacy of the nerves, he did not upon that foundation
attempt to establish his practice. He considered the living body as one
machine, the _whole_ of which might be acted upon, and always was acted
upon by certain powers. It possesses a certain inexplicable property
called _excitability_, capable of being augmented or diminished. Every
power which augments the _excitability_ he called a _stimulus_; the
opposite would have been a _sedative_; but according to this system
there is not any sedative, nor can there be one in nature. The reason
is, that excitability itself has no existence but in consequence of
the action of certain powers called _stimulants_. The total subduction
of these reduces the excitability to nothing; of consequence no power
can act against it in a state of non-existence. What other physicians
call _sedatives_, therefore, according to the new system, are only weak
_stimulants_. The fallacy of such reasoning is obvious; but as it does
not affect the practice, we shall not spend any time in considering it
further.

On the principles just now laid down, the Brunonian system divides all
diseases to which the human body is liable into two great classes;
the one produced by too much excitement, the other by too little. The
former contains those diseases by other physicians called inflammatory;
the latter such as are called nervous, putrid, or all in which the
powers of life are too weak, and require to be supported. This last
is supposed to be much more numerous than the former; and in the cure
of these it was that the founder of the system appeared to greatest
advantage. A most violent altercation took place between Dr. Brown and
the Edinburgh College; yet, notwithstanding all the influence of the
professors, and their unanimous opposition to the new doctrines, they
found themselves ultimately unable to resist a single man unsupported
either by wealth or reputation. The plausibility of his system, and
its being obvious to every capacity, overcame every obstacle; so that
even the practice of the Cullenians themselves underwent considerable
alterations. It is not, however, to be denied that the system hath
been considerably improved, or at least altered, by some of Dr.
Brown’s pupils, who have had the advantage of extensive practice,
and of visiting many different countries; which the Doctor himself
never had. His materia medica was besides exceedingly confined; the
only medicines he had any great opinion of, being laudanum and ardent
spirits. The Peruvian bark he held in very little estimation, as being
a weak stimulus. He seems to have been unacquainted with the virtues
of mercury, except in the venereal disease, and most probably would
have given laudanum in those cases of fever where mercury is found by
others to be so efficacious. But this deficiency hath been abundantly
supplied by some of his followers. In a work entitled “The Science
of Life,” published by Dr. Yates and Mr. McLean, practitioners in
the East Indies, we find mercury exhibited in prodigious doses. As a
specimen we shall select their third case, which was a dysentery. On
the first of September the patient took two grains of calomel and as
much opium every two hours. This was continued for two days. On the
third, the dose was given every hour; besides which, he had half an
ounce of mercurial ointment with a drachm of calomel rubbed into his
body. Next day the pills were continued, and the quantity of ointment
tripled by thrice rubbing in. This was continued for three days, at
which time, an eruption on the skin appearing, it was feared he could
not be salivated; this eruption being a sign that no salivation could
be produced. The same mode of treatment, however, was persisted in.
September 7th the calomel in the pills was augmented to four grains;
the warm bath was used, and the ointment continued; but at night twenty
grains of calomel and six of opium were given every two hours. At the
same time two ounces of ointment, with four of calomel, were ordered
to be rubbed in. Next day, though his pulse was almost imperceptible,
and his extremities cold, “the medicines were continued as far as
circumstances would admit;” with what view it is not said, nor indeed
is it easy to be discovered. At one in the morning, however, the
patient died; an event not at all surprising. Our authors excuse
themselves for this failure by saying that the viscera of the patient
were diseased, as was evinced by the impossibility of exciting a
salivation; and “that when a patient is evidently incurable by the
common practice, it becomes the duty of the practitioner to depart from
it.”

No doubt we may readily assent to both these assertions; but though
a patient be evidently incurable by the common practice, or by any
other, there is no necessity for killing him, or for persevering in
a course of violent medicines that evidently make him worse. The
whole of this case indeed strongly militates against the doctrine of
excitement; for if mercury be such a powerful stimulus to the powers
of life in general, how comes it to pass that in the present case the
unhappy patient, instead of being in the smallest degree excited, was
prodigiously debilitated, and that from the very first time of taking
the medicines. This will appear from the following table, exhibiting
the symptoms of the disease as they kept pace with the medicines taken.

DAYS OF THE     MEDICINES TAKEN.             SYMPTOMS.
MONTH.

_August 29      Ordinary doses of            Pain of bowels,
& preceding._   mercury and opium.           and frequent stools,
                                             growing worse.

_Sept. 1 & 2._  Opium and mercury,           Still increasing.
                two grains
                each, every two
                hours; besides opiate
                draughts.

3d              The opium and                Stools very frequent,
                mercury as before,           with violent
                but now given every          pain in the bowels;
                hour; half an                extreme thirst,
                ounce of mercurial           tongue furred, and
                ointment, with 60            no sleep.
                grains calomel.

4th             Pills as usual.              Vomiting during
                Ointmt. thrice rubbed        the night. Tongue
                in, once with                brown and furred.
                120 grains of mercury.

5th             Medicines as before.          Violent pain in bowels.

6th             Medicines as before.          Extreme pain on
                                              pressing the arch
                                              of the colon; frequent
                                              stools, profuse
                                              sweats, great dejection
                                              of spirits.


7th             Pills as before,              As yesterday. An
                with four grains of           eruption on the skin.
                calomel. Mercury              At night incessant
                in the ointment increased     stools, with violent
                to half an                    pain in the belly;
                ounce. Warm bath.             profuse sweat.
                At night an ounce
                of mercurial ointment,
                with two ounces
                calomel.

8th     Pills, ointment &     Incessant stools
        calomel as before.    with violent pain;
        Warm bath thrice.     at night with blood.
        At night two ounces   Extreme debility.
        ointment, with four
        of calomel.

9th     Medicines of the      Stools innumerable;
        same kind, as many    extremities
        as could be taken.    cold, pulse scarce to
                              be felt.

10th                          Death at one in
                              the morning.

From a consideration of this patient’s symptoms, in comparison with the
quantity of mercury taken, it most evidently appears, that it acted
in no other way than as an irritating poison; affecting, with extreme
violence, the already diseased intestines, and, instead of exciting
the vital powers of the whole system, manifestly destroying them. Let
it not be imagined, however, that this case is selected from the rest
merely because it was fatal, or because it affords an opportunity of
finding fault with the practice recommended in the book. It is the only
one in which the mercury had a fair trial; and even here it was not
very fair, as being conjoined with a great quantity of opium. In the
other cases, which terminated favourably, the mercury was overpowered
by such horrible doses of opium, that we cannot tell which medicine
had the greatest share in the cure; besides, that in other cases the
patients were allowed the free use of wine, which we all know to be a
powerful stimulant and cordial; but it is not said that the poor man,
whose case is above related, had a single drop of wine, or any thing
else, except opium, to support him against the action of such a violent
medicine.

On this case it is of importance still to remark, that it affords,
in the strongest manner, an argument against what our authors say,
p. 86, that “mercury acts by supporting the excitement of the whole
body, it invigorates each particular part; and thus occasions, to a
certain extent, the regeneration of those organs which may have been
injured by disease.” In the instance adduced, there is no evidence of a
stimulus upon any other part of the system than the bowels, which were
already debilitated or diseased in such a manner that they could not
bear it. The system in general, instead of being excited, was sunk and
debilitated from the very first moment, until at last the excitement
terminated entirely by the patient’s death. But further: There is very
little probability that mercury or any other medicine whatever can
prove a general stimulus, and that for the following reasons.

1. No medicine can assimilate with the substance of the body. Medicines
properly so called are here alluded to. Food or drink of any kind taken
for the support of the body while in health, however they may act
medicinally upon occasions, are excepted.

2. The body is composed of many various substances, each differing in
its nature from the other. The nature of the medicine, whatever it may
be, is uniform, and cannot act upon substances of different kinds in
an uniform manner; and without this there can neither be an universal
stimulant, nor an universal debilitant.

3. All medicines, being incapable of assimilation with the body,
must be considered, when taken into it, as foreign matter; and the
introduction of them at any rate is in fact the creating of a disease.
This is evident from multitudes of instances where people by quacking
with themselves, and taking medicines unnecessarily, have destroyed
their health.

4. As every medicine has one peculiar nature, and one mode of action
in consequence of that nature, it must, when introduced into the body,
where there are fluids of various natures, act upon one of them more
than the rest; and this may be called the _chemical_ action of that
medicine upon the body.

5. In consequence of the chemical action of the medicine, the mode
by which it is expelled out of the body will be different; for, as
all medicines are extraneous substances, they must be sent out of the
body as fast as possible; and it is their action upon one particular
part which promotes their expulsion. Thus, if from the nature of the
medicine it acts in a certain way upon the stomach and bowels, it will
vomit or purge, or perhaps both; and by this action it is expelled
from the body, along with whatever other matters happen to be in the
stomach or intestines; and thus medicines do good only accidentally;
for mere vomiting or purging are most certainly diseases; but where
noxious matters exist in the bowels, and do not naturally excite
these operations, an emetic or purgative is unquestionably useful.
Here the authors of the Science of Life reason differently; and it is
worth while to refute their argument, as being the foundation of such
_tremendous_ practice as nobody of common sense would choose to be the
subject of. Of tartar emetic they speak in the following terms. “That
tartar emetic is a stimulant of very high power, is evident from the
small quantity of it which produces the state of indirect debility that
occasions vomiting. It should be given in such a manner as to increase
and to support the excitement. But this will be found difficult, as the
duration of its action seems to be even shorter than that of opium.
If its action does not continue more than a quarter of an hour, might
it not be repeated at such short intervals, and the doses so reduced
as to allow the establishment of the indirect debility?” This is
arguing in a circle. They first suppose that vomiting is occasioned
by indirect debility, that is, the weakness produced by an excessive
stimulus to the whole system, as in cases of drunkenness; and then,
from the existence of vomiting, they prove that a general stimulus
had pre-existed. The cases, however, are widely different. In cases
of drunkenness, the person feels himself at first exhilarated, alert
and active, which shows the existence of a general stimulus. But
who has ever found himself exhilarated by taking a dose of tartar
emetic? Yet in a general excitement it is absolutely necessary that
this exhilaration should take place, because it is an inseparable
consequence of an addition of vital power, let it come in what way
it will. Thus we know that if a person happens to be much exhausted
by fatigue and abstinence, he will be exhilarated and his strength
augmented by a single mouthful of meat, as well as by a glass of wine.
This shows that both these are general stimulants to the system; but
what medicine have we that will produce similar effects? Perhaps opium
comes the nearest in the whole materia medica; but the uneasiness
it occasions in the stomach manifests a greater action upon it than
the other parts; for if the whole body were equally excited, the
withdrawing of the stimulus, or its naturally losing its force, could
only have the same effect with fasting or fatigue; but the debility of
the stomach, the confusion of the head, and other effects which attend
a dose of opium, demonstrate that it acts partially, and not equally
over the whole body. The Science of Life indeed says that these effects
are owing to the improper omission of the medicine, or not repeating
the doses in due time. This may be; but no improper exhibition of
food, or want of due repetition, will produce such symptoms; which
undoubtedly is a proof that food stimulates the system in one way, and
opium in another.

6. If any medicine could be found that acted as an universal stimulus
or exciter of the whole system, it could not like others be expelled,
by any particular evacuation; but, by destroying the balance between
the force of the acting powers and the subject on which they act,
would most certainly kill, unless very powerful means were used to
counteract its effect. The only stimulant we are acquainted with which
acts equally on the whole system, and which can be readily exhibited
as a medicine, is that pure kind of air called by Dr. Priestley
_dephlogisticated_, by Scheele _empyrean_, and by the French chemists
and their followers _oxygen_. The exciting powers of this air, when
breathed instead of the ordinary atmosphere, are astonishing. It not
only augments the appetite, but the power of the muscles, and the
inclination to use them; so that without any intoxication or delirium
the person cannot refrain from action; and it not only exhilarates
the spirits in an extraordinary manner, but beautifies the face. Did
the cure of diseases therefore, or any set of them, depend on mere
excitation, no other medicine but _oxygen_ would be necessary. What
effects it may have in diseases of debility is not yet ascertained; but
to persons in health it certainly proves fatal: their bodies are unable
to bear its powerful action, and of consequence they waste, and would
die of consumptions, if its effects were not counteracted. Nor is this
at all an easy matter; for Dr. Beddoes informs us that, by breathing
this air for a short time each day, only for three weeks, he found
himself in great danger of a consumption, and was obliged to use much
butter and fat meat in his diet, besides giving up the use of the air
altogether, in order to get clear of its mischievous effects.

Another mode of stimulating or exciting the whole system is, by
putting into it a larger quantity of blood than it naturally contains.
This is entirely similar to the breathing of _oxygen_; especially if
arterial blood be used, which has already imbibed its spiritous part
from the atmosphere. In the last century the transfusion of blood was
proposed not only as a mode of curing diseases, but of restoring old
people to youth; and Dr. McKenzie, in his Treatise on Health, quotes
from the memoirs of the Academy of Sciences several instances of the
blood of brute animals being infused into human veins, without any
inconvenience. It seems, however, not only a bold but an unnatural
attempt to use the blood of beasts for such a purpose; and, however
lavish mankind may be of their blood upon certain occasions, it is
to be feared that there are few who would be willing to spare any to
relieve another from sickness; but indeed little can be said about the
practice; as, on account of some bad consequences, or failures, it was
forbidden by the king of France, and by the pope’s mandate in Italy,
and has now fallen into disuse. In a paragraph at the end of Heister’s
surgery (4to edition) it is asserted that the transfusion of blood was
productive of madness. Dr. Darwin, however, in his Zoonomia, still
proposes the transfusion of blood as a remedy, and even describes a
convenient apparatus for performing the operation. In one part of his
work he says, “Might not the transfusion of blood, suppose of four
ounces daily, from a strong man, or other healthful animal, as a sheep
or an ass, be used in the early state of nervous or putrid fevers?”
In another place he mentions his having proposed it to a gentleman
whose throat was entirely closed up by an incurable swelling, so that
he could swallow nothing. This is a disease not very rare, and which
always must be fatal; because the patients, though not affected by
any sickness, die of hunger; and, to relieve them from this miserable
situation, extraordinary attempts are not only allowable but laudable.
The Doctor proposed to his patient, “to supply him daily with a few
ounces of blood taken from an ass, or from the _human animal_, who is
_still more patient and tractable_, in the following manner: To fix a
silver pipe, about an inch long, to each extremity of a chicken’s gut,
the part between the two silver ends to be measured by filling it with
warm water; to put one end into the person hired for that purpose, so
as to receive the blood returning from the extremity; and when the gut
was quite full, and the blood running through the other silver end,
to introduce that end into the vein of the patient, upwards towards
the heart, so as to admit no air along with the blood. And, lastly, to
support the gut and silver ends on a water plate filled with water of
98 degrees of heat; and, to measure how many ounces of blood were taken
away, to compress the gut from the receiving pipe to the delivering
pipe.” The gentleman desired a day to consider of this proposal, and
then another; after which he totally refused it, saying that he was now
too old to have much enjoyment of life, and that, being so far advanced
in a journey which he must certainly accomplish sooner or later, he
thought it better to proceed than return. The Doctor informs us that
he died a few days afterwards, seemingly very easy, and careless about
the matter. One experiment of this kind I have been witness to; not
indeed on a human creature, but on a calf. This creature received into
one of its jugular veins a considerable quantity of blood from the
carotid artery of another, nearly of the same age (about a month, or
little more.) It was impossible to say any thing about how much was
transfused; only the bleeding was continued till the animal which lost
the blood began to shew signs of faintness. The artery was then tied
up, and the orifice in the jugular vein closed. The calf which had
lost the blood appeared very languid and faint, but lived a few days
in a drooping state; when it either died of itself, or was killed,
as being supposed past recovery. The other, which had received the
blood, appeared to be in every respect highly excited. It became
playful, even in the room where the operation was performed, its eyes
assumed a bright and shining appearance, and its appetite was greatly
increased. Thus it continued for about a fortnight; appearing all the
time to be in high health, and eating much more than usual; but at last
died suddenly in the night. From these effects on healthy subjects,
however, we cannot infer what would happen in such as are diseased;
but it is plain that if the cure of diseases were to depend upon mere
_excitation_, the means are in our power, without any local irritation,
which always must take place in some degree by the use of ordinary
medicines. This path is not absolutely untrodden: the pneumatic
practitioners of the present day have tried oxygen in consumptions, and
found it pernicious; and Dr. McKenzie informs us that the transfusion
of blood was tried ineffectually in the same.

7. As all the medicines usually prescribed at present are only to be
accounted partially stimulant, or as acting upon particular parts of
the system, we see that some may promote one evacuation, and some
another; while all produce some change in the organization, which may
prove useful or detrimental, may increase the disease or cure it,
or may produce another, according to the judicious or injudicious
application. But for a knowledge of all this we must be indebted to
experience: there is not a theory on earth that can lead us a single
step.

Before we dismiss the consideration of medical theories, however,
it will still be necessary to give some account of the new system
as it hath branched out in various ways: for though the fundamental
principle is now received by a great number of physicians, yet the
superstructure is exceedingly different from what Dr. Brown himself
erected and, indeed, from the very same principles we find conclusions
made as directly opposite to one another as can be expressed in words.
Drs. Yates and McLean, for instance, at Calcutta in the East Indies,
have concluded that the plague “is a disease of a very high degree of
exhaustion;” which Dr. Brown would have called debility. Dr. Rush at
Philadelphia, proceeding also upon the Brunonian principles, determines
it to be the most inflammatory of all diseases,[62] and which Dr. Brown
would have called a disease of excitement. These two doctrines are, in
every sense of the word, as distant from one another as east from west.
Let us then consider both, if any consideration can avail us on the
subject.

  [62] See above, p. 102.

By the ancients it was supposed that diseases were occasioned by
something either bred in the body or received into it, and that the
power of nature produced, during the course of the disease, a certain
change in this matter, called _coction_, or _concoction_; which, if we
please, we may express by the English word _cooking_. The matter of the
disease, called also _morbific_ matter, thus _cooked_, was in a state
proper for expulsion, and was therefore thrown out by sweat, vomit,
stool, &c. or it might be expelled artificially, which could not have
been attempted with safety before. Modern systems deny the existence
of morbific matter, and resolve all into an affection of the nerves,
according to Dr. Cullen by certain sedative causes, but according
to Dr. Brown by an accumulation in some cases, and an exhaustion in
others, of the excitability or excitement of the body. The Science of
Life commences with stating what they suppose to be an improvement
of the Brunonian principles, and from which the following account of
the origin of diseases is extracted. “Upon the different states of
_excitability_ depend all the phenomena of health and disease. There
are three states of the excitability. 1. The state of accumulation;
when a portion of the usual stimuli is withheld.... When a portion
of the usual stimuli is withheld, the excitability accumulates, and
the body becomes susceptible of impression in the direct ratio of
the subduction. This state constitutes diseases of accumulation,
or of direct debility. 2. The middle state; when the excitability
is such that the application of the accustomed degree of exciting
powers produces _tone_ or _health_. 3. The state of exhaustion. When
the application of stimuli has been greater than that which produces
healthy action, the excitability is exhausted, and the body becomes
less susceptible of impression in the direct ratio of the excess. This
state constitutes diseases of exhaustion, or of indirect debility. The
states of accumulation and exhaustion of the excitability, in their
different degrees, constitute all the diseases to which living bodies
are subject.”

Here the chime runs on the word _excitability_, which is not defined.
If we call this property _life_, then we are only informed, that, as
life is more or less vigorous, the body enjoys a greater or smaller
degree of health; which we know without any medical instructor. If,
instead of the accumulation and exhaustion of excitability, we take the
original doctrine of excitement and debility laid down by Dr. Brown
himself, we are nothing better. The whole theory is lost for want of
the definition of a single word. As long as _excitability_ remains an
unknown property, we can explain nothing by it. We may indeed vary
our terms. We may call it _nervous influence_ with Dr. Cullen, or
_sensorial power_ with Dr. Darwin; but we shall still be as much in the
dark as ever; and all that can be made out of our theories, when our
language is _decyphered_, must be, that sometimes people are well, and
sometimes they are sick!

Dr. Rush, in his Treatise on the Proximate Cause of Fever, adopts in
part Dr. Brown’s system pretty nearly as the author himself laid it
down. “Fevers of all kinds (says he) are preceded by general debility.
This debility is of two kinds, viz. direct and indirect. The former
depends upon an abstraction of usual and natural stimuli; the latter
upon an increase of natural, or upon the action of preternatural,
stimuli upon the body.... Debility is always succeeded by increased
excitability, or a greater aptitude to be acted upon by stimuli.... The
diminution or abstraction of one stimulus is always followed by the
increased action of others.” Here it is evident we are as much in want
of definitions as ever. We know neither what _excitability_ is, nor
what _debility_ is, and yet they are both held out as the _causes_, and
_proximate_ or _immediate_ causes, too, of symptoms produced by things
quite obvious to our senses. Thus cold and heat, with which we are
daily conversant, are only called the _predisposing_ causes of fever;
while _debility_ and _excitement_, words to which we have no meaning,
are said to be the _proximate_ cause. It would certainly be better to
throw away such words altogether, and say that cold, heat, &c. cause
fevers, without troubling ourselves farther about the matter.

It remains now to take into consideration the pneumatic theories,
founded upon the discoveries made by Dr. Black, Dr. Priestley,
Lavoisier, and others, concerning various kinds of aerial fluids, or
_gases_,[63] as they are also called. Some of these, particularly
that afterwards called fixed air, were discovered by Van Helmont.
Considerable advances were made by a German chemist, named _Mayow_, in
the last century; but his book had fallen into such oblivion that his
name was scarce ever mentioned, until his discoveries were repeated,
and still greater advances made by others. Dr. Hales obtained air from
a great many different substances, but was unable to ascertain any
thing concerning its nature. Dr. Black of Edinburgh laid the foundation
of pneumatic chemistry, by discovering that a certain species of air is
capable of being absorbed by earths of different kinds, and that many
very heavy substances owe at least one half of their weight to this
condensed air. The discovery was accidental. Wishing to obtain a very
pure and white lime, he had recourse to the fine white earth called
_magnesia alba_. Some of this he distilled with a heat sufficient to
make the vessel red hot. Only a very small quantity of water came over,
but the magnesia had lost almost two thirds of its weight. This immense
loss was found to arise from an emission of air during the operation;
and by other experiments it was likewise found that the air might be
transferred from one portion of magnesia to another from which it had
been previously expelled; that the existence of this species of air in
certain bodies was the cause of that fermentation which takes place
when any acid is poured upon them, as vinegar upon chalk or potash.
Hence if any of these substances be deprived of its air, it will not
any longer ferment in this manner. It must not be forgot, however,
that when air thus unites itself with any terrestrial substance it no
longer has its former properties. It is reduced exceedingly in bulk,
and in proportion to this reduction only the body is increased in
weight; and therefore though we say that the _air_ is absorbed, we must
still remember that only _one part_ of it is so, and that by far the
least considerable in bulk. A violent fire will always expel the air
again, and restore it to its former bulk; and again the condensation
or absorption of the air is always attended with the production of
heat. This last property was not much attended to by Dr. Black, but
others have observed it; and the late Dr. Charles Webster of Edinburgh
published a theory in which he maintained that condensation was in
_all_ cases the cause of of heat. But, however true it may be that
condensation of any kind is followed or accompanied by heat, it is
evidently necessary to know the cause of the _condensation_ also,
otherwise we make no advance in solid theory.

  [63] _Gas_ is a German word, or derived from one, signifying
  _spirit_. The word _ghost_ comes from the same original.

The aerial fluid, discovered by Dr. Black, was one of those most
commonly met with. He called it _fixed air_, from its property of
adhering or fixing itself to different bodies. It was found to be the
same with that which had been discovered by Van Helmont, and by him
named _gas sylvestre_ (spirit of wood)[64] or the fume of charcoal;
it was found to be the same with the steam of fermenting liquor, and
with that very frequent and dangerous vapour, met with in coal mines,
called in Scotland the _choke-damp_. Like other discoveries, this was
quickly pushed beyond its proper bounds, and applied to the solution of
phenomena which it could not solve. Dr. MBride, particularly, supposed
it to be the bond of union between the particles of matter, or in other
words the principle of cohesion itself. It was also supposed to be
the substance of those scorching winds, called _samiel_, met with in
Asia and Africa, and which sometimes prove fatal to travellers. The
pernicious vapours called _mofetes_, which sometimes issue from the old
lavas of Vesuvius in Italy, were likewise supposed to be the same;[65]
but of this, particularly with regard to the samiel, there seems to be
no sufficient evidence.

  [64] This must be understood only of its general properties and
  effects; for, though the fume of charcoal possesses many of the
  apparent properties of pure fixed air, it contains also a very
  considerable quantity of another kind of gas.

  [65] Many fabulous stories have been related concerning the samiel.
  Even so late a traveller as Mr. Ives has adopted some of those
  exaggerated accounts which have been discredited by those who have
  long resided in the countries where this wind is commonly met with.
  It is not peculiar to the deserts of Arabia, but is met with in all
  hot countries which are destitute of water. In the African deserts
  therefore it is common; and Mr. Bruce describes it by the name of
  _simoom_. It was preceded by whirlwinds of a very extraordinary
  kind. “In that vast expanse of desert (says he) from W. and to N. W.
  of us, we saw a number of prodigious pillars of sand at different
  distances, at times moving with great celerity, at others walking on
  with a majestic slowness. At intervals we thought they were coming
  in a very few minutes to overwhelm us; and small quantities of sand
  did actually more than once reach us. Again they would retreat so as
  to be almost out of sight; their tops reaching to the very clouds.*
  There the tops often separated from the bodies; and these, once
  disjoined, dispersed in the air, and did not appear more. Sometimes
  they were broken near the middle, as if struck with a large cannon
  shot. About noon they began to advance with considerable swiftness
  upon us, the wind being very strong at north. Eleven of them ranged
  along side of us at about the distance of three miles. The largest
  of them appeared to me at that distance to be about ten feet
  diameter.... It was in vain to think of flying; the swiftest horse or
  the fasted sailing ship could be of no use to carry us out of this
  danger; and the full persuasion of this rivetted me as if to the spot
  where I stood.” At another time he saw them in much greater number,
  but of smaller size. They began immediately after sunrise, like a
  thick wood, and almost darkened the sun. His rays darting through
  them gave them the appearance of pillars of fire. They now approached
  to the distance of two miles from our travellers. At another time
  they appeared beautifully spangled with stars. in Darwin’s Botanic
  Garden we find a reason assigned for the appearance of these
  whirlwinds; viz. the impulse of the wind on a long ledge of broken
  rocks which bound the desert. By these the currents of air which
  struck their sides were bent and were thus like eddies in a stream of
  water which falls against oblique obstacles. In the same work we have
  the following poetical description of them:

    * _N. B._ In these sandy deserts, where it never rains,
      there are no clouds.

          “Now o’er their heads the whizzing whirlwinds breathe,
          And the live desert pants and heaves beneath;
          Ting’d by the crimson sun, vast columns rise
          Of eddying sands, and war amid the skies,
          In red arcades the billowy plains surround,
          And whirling turrets stalk along the ground.”

  Whether the simoom is always preceded by these whirlwinds we know
  not; but Mr. Bruce mentions an extreme redness of the air, pointed
  out by his attendant Idris, as the sure presage. His advice was, that
  all of them, upon the approach of the pernicious blast, should fall
  upon their faces, with their mouths on the earth, and hold their
  breath as long as possible, so that they might not inhale the deadly
  vapour. They soon had occasion to follow this advice; for next day
  Idris called out to them to fall upon their faces, for the simoom
  was coming. “I saw (says Mr. Bruce) from the S. E. a haze coming, in
  colour like the purple part of the rainbow, but not so compressed
  or thick. It did not occupy twenty yards in breadth, and was about
  twelve feet high from the ground. It was a kind of blush upon the
  air, and it moved very rapidly; for I could scarce turn to fall upon
  the ground, with my face to the northward, when I felt the heat of
  its current plainly upon my face. We all lay flat on the ground, as
  if dead, till Idris told us it was blown over. The meteor, or purple
  haze, which I saw, was indeed passed; but the light air that still
  blew was of heat sufficient to threaten suffocation. For my part, I
  felt distinctly in my breast that I had imbibed a part of it; nor
  was I free of an asthmatic sensation till I had been some months
  in Italy, at the baths of Poretta, near two years afterwards.” It
  continued to blow for some time, and in such a manner as entirely to
  exhaust them, though scarcely sufficient to raise a leaf from the
  ground.

  The account given by Mr. Ives is, that it blows over the desert (of
  Syria) in the months of July and August, from the northwest quarter,
  and sometimes continues with all its violence to the very gates of
  Bagdad but never affects any body within its walls. Some years it
  does not blow at all and in others it comes six, eight, or ten times,
  but seldom continues more than a few minutes at a time. It often
  passes with the apparent quickness of lightning. The sign of its
  approach is a thick haze, which appears like a cloud of dust rising
  out of the horizon, on which they throw themselves with their faces
  on the ground, as already mentioned. Camels are said, instinctively,
  to bury their noses in the sand. As for the stories of its dissolving
  the cohesion of the body in such a manner that a leg or an arm may
  be pulled away from those who are killed by it, or that their bodies
  are reduced to a gelatinous substance, we cannot by any means give
  credit to them. From its extreme quickness, and luminous appearance,
  it would seem to be an electrical phenomenon immediately preceding
  those vehement hot winds which all travellers agree in likening to
  the vapour issuing from a large oven when the bread is newly taken
  out. Its electrical nature will be more probable from the account
  given by Mr. Ives, that the Arabians say it always leaves behind it a
  very sulphureous smell. These particulars do not at all accord with
  the supposition of its consisting of fixed air. I have indeed been
  assured by a gentleman long in the service of the English East India
  Company, that the samiel cannot pass over a river. Hence probably it
  has been supposed to be a blast of fixed air, because this species
  of gas is readily absorbed by water; but we know that the same thing
  would also take place with any quantity of electric matter; for water
  takes up this also much more completely than it does fixed air.

  The _mofetes_ are invisible, and kill in an instant. They rise from
  old volcanic lavas, and, as it were, creep on the ground, and enter
  into houses, so that they are very dangerous; but, though they may
  probably consist of fixed air, we have not as yet any direct proof
  of it. It is not indeed easy to imagine why any lava should suddenly
  emit a great quantity of fixed air, and then as suddenly cease; nor
  in what manner the air thus emitted should continue unmixed with
  the atmosphere; for fixed air will very readily mix in this manner,
  insomuch that a large quantity of it being let loose in a room has
  been found to vanish entirely in less than half an hour. Sir William
  Hamilton mentions a mofete having got into the palace of the king of
  Naples.

The industry of other experimenters did not long leave theorists
without abundance of materials upon which they might exercise their
talents. It is impossible in this place to assign to each his proper
rank in the way of discovery, or indeed to mention their names. Dr.
Priestley has distinguished himself far above the rest. He not only
repeated and improved Dr. Black’s experiments on _fixed air_, but
likewise found out a number of other kinds; particularly that from
animal substances in a state of putrefaction, which is so pernicious
to living creatures, insects excepted; for these last will thrive
amazingly in air that would prove certain death to a man. He also
discovered that this kind of air, and some others, were absorbed by
vegetables, and thence inferred the use of vegetables in purifying
the atmosphere. He even analysed the atmosphere itself, and found
that it consisted of two different kinds of fluids, one of which he
called _dephlogisticated_, the other _phlogisticated_ air. The former
was found to support animal life for a time, the latter to destroy it
instantly. Their effects upon fire were the same; the former exciting
the most vehement heat and bright flame, the latter extinguishing a
fire at once.

The fame of Dr. Priestley’s discoveries quickly reached the continent
of Europe; the French chemists repeated his experiments with
improvements, as they thought; and indeed certainly made many curious
discoveries. Lavoisier was particularly remarkable for his numerous
and accurate experiments; but, by his changing entirely the language
of former chemists, and substituting a set of new terms of his own
invention, he certainly entailed the greatest curse upon the science
it ever met with. It belongs not to this treatise to give an account
of his system farther than to say, that, from the immense proportion
of condensed aerial matter found in most terrestrial substances, he
and his followers were led to conclude, that different species of
air constitute almost the _whole_ of the terraqueous globe. Water
particularly they have absolutely and most positively determined to
be a composition of two airs condensed, viz. the dephlogisticated and
inflammable, which they call _oxygen_ and _hydrogen_. However, this
doctrine is still opposed by Dr. Priestley and some others.

In the midst of so much theory, and so many new and surprising
discoveries, it would have been wonderful indeed if the science of
medicine had kept free from innovation. It did not: the new chemistry,
with all its formidable apparatus of hard words, was introduced,
and thus the study of the science, already very difficult, was
rendered still more so. In passing this censure upon the modern
_nomenclature_, as it is called, I am sensible that I must rank with
the minority; nevertheless, I have the satisfaction of finding that I
am not altogether singular. Dr. Ferriar, in the preface to his second
volume, complains, “that, with every attempt towards the formation
of a system, new applications of words are introduced, which, though
desirable in the art of poetry, are very inconvenient in pathological
books, especially when this is done to give an air of novelty to old
theories and observations. For, between the ancient language, which
practitioners cannot entirely reject, and the new dialect, which they
cannot wholly adopt, the style of medical books is reduced to a kind
of jargon, that the author himself may possibly understand, but which
his readers find it very difficult to unriddle. Hence results a neglect
of medical literature, and hence the pernicious habit of regarding as
new whatever has not appeared in the publications of the last half
century.” To the same or a similar purpose, in the preface to his first
volume, he cites Quintilian. [66]“Some have such a multitude of vain
words, that, while they are afraid of speaking like other people, by a
kind of affected elegance, they confound every thing they have to say
with their immense loquacity.”

  [66] Est etiam in quibusdam turba inanium verborum, qui dum communem
  loquendi morem reformidant, ducti specie nitoris, circumeunt omnia,
  copiosa loquacitate, quæ dicere volunt.

The pneumatic system naturally arose from a consideration of the
composition of the atmosphere we breathe. Finding this fluid to be
composed of two others, the one of which would preserve life for some
time at least, and the other instantly destroy it, it became natural to
think that diseases might be produced by any considerable variation in
the proportion of these ingredients. An instrument was soon invented by
which any considerable variation in this respect might be discovered;
but upon trial this was found to be of very little use. Dr. Priestley
himself tried, by means of this instrument, some very offensive air
which had been brought from a manufactory, and could find no remarkable
difference between it and that which was accounted pure. Still,
however, it was evident that by increasing very much the proportion
of one of the ingredients, some considerable alteration might be
produced, which could not but be perceptible in the human body; and
this led to the application of aerial chemistry to disorders of the
lungs. The mixture chosen for this purpose was pure dephlogisticated
(_oxygen_) with inflammable air (_hydrogen_;) and, though this has not
been known to effect a radical cure, it certainly has given relief in
many cases. In fevers also the application of fixed air (carbonic acid)
hath been found advantageous; but with regard to oxygen and some others
we have not yet a decided instance of their good effects in any case.
Dr. Beddoes indeed is of opinion that it would be of service in the
sea-scurvy; but in this (whether his conjecture be right or wrong) the
theory is certainly erroneous, as shall presently be evinced.

In considering the pneumatic system it is evident that modern chemists
have fallen into the same error with their predecessors, viz. of
supposing that every thing which by the force of fire or otherwise they
could produce, from any substance, previously existed in it. Hence, as
from a piece of bone for instance, a chemist can produce water, salt,
oil and earth, it was supposed that these four were the principles or
elements of the bone. But this was false reasoning; for if these were
really the chemical principles, they ought to have been able to produce
some kind of bony substance by mixing them together after they had been
distilled. But no such thing could be done; and though we should add to
the mixture the whole quantity of air emitted during the distillation,
and which escaped the notice of ancient chemists, our success would
be no better. In like manner, because in certain circumstances oxygen
is obtained from the flesh of animals, it has been concluded that it
necessarily exists as an ingredient in their bodies while living; and
that, if this kind of air happens to predominate, the animal will be
affected in one way, or if hydrogen prevail, in another. But though
we have already quoted Dr. Girtanner with approbation as having
obtained oxygen gas from fresh meat, yet this does not by any means
prove to us that it exists in flesh as one of its component parts.
Even in the Doctor’s experiment it was necessary to expose the flesh
to the atmosphere in order to procure the gas by distillation; which
undoubtedly must excite a strong suspicion that the air in question
comes from the atmosphere itself; and, if this is the case, it is not
reasonable to suppose that a disease could be cured by any addition
of oxygen to the solid parts; because, though sound flesh may have an
inclination to absorb this kind of air, we do not know whether it would
have such a property of absorption in a diseased state. Indeed in the
scurvy, which Dr. Beddoes chooses as an example, experiment seems to
determine in favour of _fixed air_ rather than any other. But let us
hear Dr. Girtanner himself, who has at large discussed this subject
in two memoirs; one upon the laws of irritability, and another on the
principle of irritatibility.

In these memoirs we find the Brunonian doctrine set forth with such
silence in regard to Dr. Brown himself, that some have not scrupled to
charge Dr. Girtanner with literary _theft_; but this is a matter which
belongs not to us to consider: the theory may be very good, whether
stolen or not. He changes the word _excitability_, used by Dr. Brown,
for _irritability_; but hath the misfortune of not being able to tell
us what he means by it. He goes on, however, to distinguish the three
states of _tone_ or health, _accumulation_, and _exhaustion_, as other
Brunonians do. Health, he says, in a fibre “consists in a certain
quantity of the irritable principle necessary for its preservation. To
maintain this state, the action of the stimulus must be strong enough
to carry off from the fibre the surplus of this irritable principle
which the lungs and the circulation of the fluids are continually
supplying. For this a certain equilibrium is necessary between the
stimuli applied and the irritability of the fibre, in fine that the sum
of all the stimuli acting upon it may be always nearly equal; powerful
enough to carry off from the fibre the excess of its irritability, and
not so strong as to carry off more than this excess.... When the sum
of the stimuli acting upon the fibre is not great enough to carry off
all its excess of irritability, the irritable principle accumulates in
the fibre, and then it is found in that state which I call the _state
of accumulation_; the irritable principle accumulates in the fibre,
its irritability is augmented, and the stimuli produce much stronger
contractions than when the fibre only retains its tone.... When the
sum of the stimuli acting upon the fibre is too great, the fibre is
deprived not only of the excess of its irritability, but also of some
portion of the irritable principle necessary for the tone of the fibre;
or, more properly speaking, the fibre loses more irritability than
it receives, and, of course, in a short time finds itself in a state
of _exhaustion_; and this exhaustion will be either _temporary_, or
_irreparable_.”

Here it is evident that we have nothing but Dr. Brown’s system, without
the least explanation to render it more intelligible. A definition
is still wanting. This invisible and incomprehensible property of
_irritability_ ruins our whole fabric; nor can the deficiency be
supplied by human art or skill: of consequence we must abandon this
part of the system entirely, and come to something more cognizable
by our senses. It is impossible, however, to pass over in silence
the amazing inattention of the author, in imagining that on such
unintelligible principles he could explain other phenomena. “In the
state of _temporary exhaustion_ (says he) the fibre loses its tone, and
fails for want of irritability. The application of a stimulus while it
is in this state will not make it contract. Provided the stimulus be
not very strong, it will produce no effect at all, but in a short time
the irritable principle will accumulate afresh in the fibre, and then
it will again contract. It is only by little and little that the fibre
recovers its irritability. This truth, I dare venture to say, is as
new as it is striking. It unfolds a vast number of phenomena hitherto
inexplicable.” Here we have nothing but the pompous declaration of a
fact already well known; viz. that not only a _fibre_, but the whole
body, may be in a state of temporary insensibility, and yet recover
either of itself or by the use of external means. How many people have
fallen into a _syncope_, and yet recovered! How many limbs have become
paralytic, and in time recovered their sense and motion! Yet this is
all that we are informed of with so much parade and assumption of
novelty. We know that when a person is in a faint he is insensible to
ordinary stimuli, though very strong ones will rouse him; but what can
we infer from this? Nothing; only we see it is so. Does it avail us any
thing to be told that during the time of fainting the _irritability_ is
exhausted, and “in a short time the irritable principle will accumulate
afresh;” in which case the patient will no doubt recover, unless he
happens to be dead, which is the true meaning of an _irreparable
exhaustion_ of the irritability.

In speaking of the principle of irritability he expresses himself in
the following manner. “I think that the oxygen is absorbed by the
blood, and that the venous blood is oxygenated in the lungs during
respiration. The most celebrated naturalists and chemists are of a
different opinion: they think that the oxygen does not combine with the
venous blood. According to them, this last loses carbon and hydrogen,
and recovers the bright colour natural to it, without absorbing any
thing from the atmosphere.... After having a long time attended the
phenomena of respiration, and made many experiments upon this subject,
I think it may be concluded that one part of the oxygen of the vital
air combines with the venous blood, of which it changes the black
colour, and makes it vermilion;[67] the second part of the oxygen
unites with the carbon contained in the carbonic-hydrogen gas, which
exhales from the venous blood, and forms carbonic acid air; a third
part unites with the carbon of the mucus, contained in great quantities
in the lungs, and which is continually decomposing; this part also
forms carbonic acid air; a fourth part of the oxygen combines with the
hydrogen of the blood to form water.”

  [67] Here Dr. Beddoes, from whose publication this account of
  Girtanner’s memoir is taken, has the following note: “Dr. Goodwyn
  had proved this before. Could Dr. Girtanner be ignorant of his
  experiments?” In justice to myself, however, I must observe that this
  very doctrine had been published in the Encyclopædia Britannica long
  before either Dr. Goodwyn or Dr. Girtanner had made any experiments
  on the subject. It may still be seen under the article BLOOD, and
  reasons are there given for supposing that only one part of the
  oxygen, viz, the elastic part, can be absorbed.

On this theory I shall only observe, that though I lay claim to the
former part, I allow the Doctor all the latter part to himself;
particularly where he speaks of the _formation_ of water to be exhaled
during respiration. The air in question consists of two parts, like
_fixed air_ already mentioned. One of these is capable of being
attracted, condensed, or united with certain substances; the other
vanishes, leaving no other traces of its having ever existed, but heat,
greater or less according to circumstances. When the air is taken into
the blood, one part of it undoubtedly combines with something thrown
out by the lungs, and forms _fixed air_, of which our breath contains
a considerable quantity. We know certainly that the condensable part
of fixed air is formed out of the condensable part of the oxygen,
with certain additions. As therefore great part of this condensable
oxygen is thrown out in fixed air at every expiration, it is natural
to suppose that all of it is so: at least we cannot know the contrary
without a series of very difficult and tedious experiments, which have
never been made by Dr. Girtanner or any body else. But if the whole
of this condensable part be thrown out, none can enter the blood by
the breath; and consequently whatever true oxygen may afterwards be
expelled from that fluid, must be a factitious substance, formed either
during the artificial process, used for distilling it, or by a natural
process In the body itself. It is not therefore at all probable that
the oxygen which flesh emits in distillation can be derived from the
air by respiration.

Another and more probable source is the food and drink we take; all
of which are more or less impregnated with air of different kinds,
particularly fixed air. This, we know, very readily condenses, and
certainly will do so when taken into the body. In this state it not
only may, but certainly will, pass into the blood, and through all the
different parts of the body, until, having accomplished its purpose,
whatever that may be, it is thrown out by insensible perspiration, as
has been already explained.

The conclusions drawn by Dr. Girtanner from his experiments are,
1. That the change of colour which the blood undergoes during the
circulation is not owing to its combination with hydrogen air[68]. 2.
The deep colour of the blood in the veins is owing to the _carbon_ it
contains. 3. That the vermilion colour of the arterial blood proceeds
from the oxygen with which the blood is conjoined during its passage
through the lungs. 4. That respiration is a process exactly analogous
to the combustion and oxydation of metals; that these phenomena are
the same, and to be explained in the same manner. 5. That, during
circulation, the blood loses its oxygen, and charges itself with
_carbonic hydrogen_ air, by means of a double affinity. 6. That, during
the distribution of the oxygen through the system, the heat which was
united with this oxygen escapes; hence the animal heat. 7. That the
great capacity of arterial blood for heat is owing to the oxygen with
which it is united in the lungs.

  [68] Here it is necessary to observe, for the sake of accuracy and
  perspicuity, that, in the new chemistry, the terms of which are
  now very generally adopted, the words _oxygen_ and _hydrogen_ when
  mentioned by themselves are not understood to signify any kind of
  air, but what I have called the condensable part of the air. If
  the word _air_ is added, then the whole substance of the fluid is
  understood. But though this is the strict orthodox language of the
  new chemistry, it is impossible to say whether every one who adopts
  the terms be sufficiently careful in this respect. Indeed this is
  one out of many inconveniences that might be pointed out which
  have arisen from this nomenclature; for thus the mere omission of
  a monosyllable, which may happen in numberless instances, totally
  perverts the meaning of the author, and may of course subject him
  to unmerited censure. Besides, it is not to be known, unless the
  author tells us so, that he designs to observe this strictness, and
  of consequence we must in multitudes of cases be uncertain of the
  meaning of what we read. Thus, in the present instance, when Dr.
  Girtanner speaks of _oxygen_, we know not certainly whether he means
  the air in substance, or only one of its component parts. Probably
  he means the condensable or solid part. If he does so, there must be
  a very material difference between his theory and that laid down in
  the Encyclopædia, and which is supported throughout this treatise. In
  the latter it is maintained that the condensable part is thrown out
  by the breath, being previously converted into fixed air, while the
  elastic part enters the vital fluid, communicating to it not only the
  red colour, but heat, and the principles of life and sensation, as
  will be more fully explained in the sequel.

On these propositions, which constitute in a great measure the
fundamental principles of the doctrine of _oxygenation_ of the human
body, we may remark,

1. Nobody can reasonably suppose that hydrogen air is the cause of the
dark colour of the blood in the veins, because there is no source from
which it can be derived; and, besides, it is certain that no kind of
air can exist in its elastic state in the blood, without destroying
the life of the animal. Some experiments proving this are given by Dr.
Girtanner himself. It is true that an aerial vapour, of the nature of
_fixed air_, exhales from the body by insensible perspiration; but
there can be no doubt that this receives its elasticity only at the
surface of the body, and is expelled the moment it is formed. It has
indeed been proved, by undeniable experiment, that no air of any kind
exists in the larger veins; because a portion of a vein, included
between two ligatures, being cut out, and put under the receiver of an
air-pump, does not swell in the least when the air is exhausted, which
yet must be the case, did the smallest quantity of elastic air exist in
it.[69]

  [69] _Hydrogen_ air is the same with that by Dr. Priestley called
  _inflammable_ air. He also discovered the true composition of it.
  Having included a few grains of charcoal in the receiver of an
  air-pump, and exhausted the air, he heated it in vacuo by means of
  a large burning glass. The charcoal was entirely volatilized and
  converted into this kind of air. He found, however, that without some
  small portion of moisture this volatilization did not take place.

2. When the Doctor asserts that the dark colour of the venous blood is
owing to the carbon it contains, he is in the first place chargeable
with the error of former chemists, who supposed that every thing which
could be extracted from any substance by fire, existed previously in
it, in that very form in which it is extracted by the fire; and in
the second place he speaks entirely at random, without even a shadow
of proof. Nay, he himself tells us, that he has repeated two of Dr.
Priestley’s experiments, which in the clearest manner demonstrate,
that neither the addition nor the abstraction of carbon, or any thing
else, give this dark colour to the venous blood. “A small glass tube
(says he) filled with arterial blood, of a bright vermilion, was sealed
hermetically,[70] and exposed to the light. The blood changed its
colour by degrees, and in six days became black as venous blood. The
same experiment was repeated, with this difference only, that the tube
was exposed to heat, and not to the light. The blood became black in
a shorter time.” In these experiments it is plain, that if the blood
contained oxygen at first, it did so at the last; the same with regard
to carbon. How came it then to pass, that without either evaporation of
the former, or addition of the latter, the change should be produced?
If the oxygen imbibed by the blood in the lungs was sufficient to
produce the red colour, why did it not preserve it? The case here is
precisely similar to what happens with the calx of silver. When that
metal is dissolved in aqua fortis, and again reduced to a solid form,
it appears as a white powder, and will preserve its colour if carefully
kept from the light; but if a vial be filled with it, and exposed to
the sun, that side on which the light falls will in a short time become
black, and this though the vial has been ever so carefully sealed.[71]
Formerly, chemists had a method of accounting for this appearance, as
well as that of the venous blood, by what they called the _evolution of
phlogiston_: but now that the very existence of phlogiston is denied,
we are deprived of this resource. But, whatever words we may use, it
is plain that in neither case have we any ideas affixed to them which
can make the matter at all more intelligible than it was before. But
with regard to the blood, we are at a considerable loss to understand
what the natural colour of it is; and indeed the question can only be
determined by examining the blood of a fœtus which has never breathed.
If the arterial blood of such a fœtus be of a dark colour, resembling
that in the veins of a grown person, we must look upon this to be
_natural_ to it, and we may as well inquire why a rose is red, or an
iris blue, as why the blood is of a dark, and not of a bright red. But,
if we find this dark red change to a bright scarlet in the arteries,
as soon as the child has breathed, we have as much reason to conclude
that the air occasions this superior redness, as that an acid is the
cause of a red colour in the syrup of violets, or an alkali of a green
colour in the same. Experiments are yet wanting to determine this
matter. Mr. Hunter has observed that “in such fœtuses as convert animal
matter into nourishment, they most probably have it (the colour of the
blood) influenced by the air, such as the chick in the egg, although
not by means of the lungs of the chick, we find the blood, in the veins
of their temporary lungs, of a florid colour, while it is dark in the
arteries.”--The probability therefore is, that the blood is naturally
dark; by the elastic principle of the oxygen that it is rendered
brighter; and that, this elastic principle being expended in the course
of circulation, the fluid reassumes its original colour.

  [70] A glass tube is sealed hermetically, by heating the open end or
  ends, till they become soft, and then closing them with a pair of
  pincers.

  [71] Thus letters, or other characters, may be curiously marked upon
  the calx within the vial, by cutting them out in paper, and then
  pasting them on the side to be exposed to the light. We may have them
  in this manner either dark upon a white ground, or white upon a dark
  ground.

3. Though enough has already been said to evince that the superior
redness of the arterial blood is derived from oxygen gas, we shall
still quote two instances from Mr. Hunter’s Treatise on the Blood,
which set this forth in the clearest manner; and these instances are
the more remarkable, because they demonstrate the phenomena not of
the _dead_, but of the _living_ body. 1. A gentleman in an apoplexy,
who seemed to breathe with great difficulty, was bled in the temporal
artery. The blood flowed very slowly, and for a long time. It was as
dark as venous blood. He was relieved by the operation; but, on opening
the same orifice in two hours, the blood flowed of the usual florid
colour. 2. A lady in an apoplexy was treated in the same manner, and
Mr. Hunter observed, that when she breathed freely, the blood from the
temporal artery assumed a bright red colour; but when her breathing
was become difficult, or when she seemed scarce to breathe at all, it
resumed its dark colour, and this several times during the operation.

4. Respiration is not, as Dr. Girtanner says, a process similar to the
combustion and oxydation (the calcination) of metals. Some of these
by calcination, and _all_ of them in the opinion of Dr. Girtanner,
unite with the condensable part of the oxygen contained in the air,
while the elastic part is dissipated in flame or heat. The reverse of
this takes place in breathing; for here the elastic part of the oxygen
unites with the blood, and makes it warm, while the condensable part,
uniting with certain particles to be thrown off from the body, passes
away in fixed air. Thus the process of respiraton does not resemble
the calcination of a metal (at least according to our author’s opinion
of that operation) but rather the inflammation of some combustible
substance; for in both cases a certain quantity of carbon is found
to be united with the basis of oxygen in the atmosphere, and thrown
off from the place of combustion; and thus a quantity of fixed air is
produced from every burning substance. Just so is it with respiration.
If the condensable part of the oxygen combined with the blood, then no
fixed air could be produced; or if any part of the oxygenous base was
absorbed, it must certainly be known by a proportional deficiency in
the quantity of fixed air produced. But there are no experiments made
with accuracy sufficient to determine this point. It is true that many
very able physiologists, as Borelli, Jurin, &c. have been of opinion,
that part of the air is absorbed in respiration; but when we come to
particulars nothing can be determined. Dr. Hales by experiment found
the quantity absorbed to be a _sixty-eighth_ part of the whole quantity
inspired; but, on account of supposed errors, he states it only at _an
hundred and thirty-sixth_ part. Between these two the difference is
so enormous, that we know not how to draw any conclusion from them.
The French chemists are more decisive, and agree pretty well with one
another. Chaptal calculates it at _three hundred and fifty-three_, and
La Metherie at _three hundred and sixty_, cubic inches in an hour.
Allowing these experiments to be just, the next question is, what
part of the air is absorbed. Lavoisier says, that it is the oxygenous
base, or the same with that which is absorbed in the calcination of
mercury. But how comes he to know this? Surely not in the same way
that he determines the absorption of it by mercury. In the latter case
he takes a certain quantity of mercury, includes it in another known
quantity of oxygen air, and heats the metal by means of a burning-glass
or otherwise: the consequence is, that the air is absorbed, the mercury
loses its fluidity, and is increased in weight. The metal gains the
_whole_ weight of the air absorbed; and, by another process, _all_ the
air and _all_ the metal, or very nearly so, may be obtained in their
original form. This experiment is so decisive, that nothing can be
said against it with any shadow of reason; but who _hath_ made, or who
_can_ make, similar experiments with the blood of a living man? Such
experiments indeed might be made, if _insensible perspiration_ did not
stand in our way. Common atmospherical air is about _eight hundred_
times lighter than water. A cubic inch of distilled water, according to
Dr. Kirwan, weighs _two hundred and fifty-three grains and a quarter_.
Oxygen air is somewhat lighter than common air: we shall therefore
suppose that six hundred inches of it are equal to an inch of water.
If then the blood absorb three hundred and sixty inches of air in one
hour, it will in twenty-four hours have absorbed eight thousand six
hundred and forty inches, equal in weight to fourteen inches of water
and two fifths, which according to Dr. Kirwan’s estimate is between
seven and eight ounces. But the quantity of matter insensibly perspired
in that time is so much greater, that no calculation can be made. Here
is one mode of determining the quantity of oxygen inspired totally
impracticable in the human body, though quite easy and practicable in
the case of mercury. The other mode of determining it by the expulsion
of oxygen from the blood is equally impracticable. Dr. Girtanner indeed
has expelled oxygen from flesh; but we know not in what proportion,
nor can we determine whence it came. With regard to this last, indeed,
there are two sources allowed by Drs. Beddoes and Girtanner themselves;
viz. the absorption of oxygen by the lungs, and the quantity taken in
with the aliment. A third source was also manifest from Dr. Girtanner’s
experiments; viz. absorption from the atmosphere; for, by exposure to
the atmosphere, flesh, which had once parted with its oxygen, became
again impregnated with it. In this case therefore we must acknowledge
that the uncertainty of the absorption by the lungs must be extremely
great. A certain quantity of oxygen is undoubtedly thrown out in fixed
air. How are we to determine this quantity? Certainly not by the first
reverie that happens to occupy our imagination. It is a problem, the
solution of which must be attended with the utmost difficulty. We must
know, in the first place, how much oxygen was contained in the air
_inspired_. In the second place we must know the quantity of fixed
air _expired_. In the third place we must exactly know the proportion
of oxygen contained in the fixed air thrown out by the breath. In the
fourth place we must determine whether, by the conversion of oxygen
into fixed air, any change is made in its bulk. For, if this shall be
found to be the case, we should be led to suppose an absorption or
augmentation of air when no such thing took place. This point therefore
ought to be determined with the utmost accuracy. In the fifth place we
must exactly know how much _azote_, _septon_, _phlogisticated air_ is
contained in the atmosphere inspired, and likewise in that expired.
In the sixth place, we must be assured that there are no other fluids
in the atmosphere capable of being absorbed by the lungs, excepting
oxygen and azote. Whether there are any others or not, hath not been
determined. From an expression of Dr. Fordyce, he would seem to be
skeptical on the subject. “The atmosphere (says he) is found to consist
of various vapours, of which air, or, as it has been called, pure
air, or respirable air, (oxygen air) forms at present about a fourth.
Gas (probably fixed air) forms some part;[72] but the greatest part
consists of one or more vapours, which, _without any positive quality,
but from that indolence which makes mankind in their researches attempt
to find a resting place, have been considered by many chemists as one
individual species, under the names of phlogisticated air_,” &c. In
the seventh place we ought to know what quantity of _pure oxygen_,
unconverted into fixed air, or whether any such, is thrown out by the
breath. That a quantity of this kind of air is really thrown out,
is probable, because we can blow up a fire with our breath, and by
a blow-pipe excite a most intense heat, capable of melting the most
refractory metals, platina excepted. It is true that the eolipile, by
the mere conversion of water into steam, will blow up a fire also;
though, if the access of external air be denied, the blast of the
eolipile will put the fire out. Probably the breath would do the same;
but even this cannot be accounted a decisive proof of the oxygen being
totally exhausted; for the moist vapour with which the breath abounds
may extinguish the fire, even though some small quantity of oxygen
should remain in it. It is not, however, our business at present to
enter minutely into such discussions. From what has been already said,
it is evident, that the absorption of oxygen by the blood, instead of
being indubitably established, is of all things the most uncertain; the
requisites for determining it being absolutely beyond the investigation
of any person, however accurate. We may indeed, with great labour and
trouble, determine that some part of the air is absorbed in breathing;
but what that part is, we are unable to discover from any chemical
investigation. The opinion of the simplicity of metals, and their being
reduced to a calx by the adhesion of oxygen, has been so implicitly,
and in a manner universally, received, that it has given a new turn
to physiology, so that, by a kind of analogical reasoning, the human
body has been reduced to a mere chemical apparatus, the operations of
which may be calculated as we can do the event of experiments in a
laboratory. But, after a very long and tedious contest, Dr. Priestley
seems at last to have overthrown this doctrine of oxygenation, even in
the inanimate parts of the creation; so that we can much less apply it
to the doctrines of life and animation. His experiments are published
in the third number of the Medical Repository, volume II, and fully
demonstrate, that, though mercury absorbs oxygen during calcination,
this is not the case with all metals; that in many cases the oxygen
will unite with other substances in preference to the metal, which last
is nevertheless reduced to a calx as though it had united with the
oxygen; that in many cases the addition of weight gained by the calx
is owing to mere water, &c. He has likewise shown that phlogisticated
air (azote) is not a simple substance, as has been taught by the new
chemists, but consists, as well as fixed air, of an union of oxygen
with carbon, or at least with the black matter of burnt bones, with
which he made the experiment. These aerial fluids therefore being
so easily convertible into one another, and the uncertainty of the
changes in bulk which may occur in consequence of these conversions
so great, it is impossible to say whether a portion of the atmosphere
in substance, i. e. both oxygen and azote, is absorbed, as physicians
formerly supposed; or whether a portion of oxygen air alone be
absorbed, as Dr. Beddoes supposes; or whether only the elastic
principle itself is absorbed, and the diminution in bulk made in
consequence of the conversion of oxygen into fixed air; I say, these
matters depend on circumstances so much beyond the reach of our senses,
that if we come to any probable conclusion upon the subject, it must be
by analogical reasoning from other known facts, not from experiments
made directly upon the living body; which, in their own nature, must,
always be extremely vague and uncertain.

  [72] It is now acknowledged that common atmospherical air contains
  a portion of what Dr. Black and Dr. Priestley have called fixed
  air; but this portion is so small (not more than one fiftieth part,
  according to Dr. Anthony Fothergill’s Prize Dissertation, and _none
  at all_, according to Dr. Beddoes) I say, this proportion is so
  small, that we cannot suppose it to constitute the quantity of fixed
  air thrown out by the breath, which is very considerable. Besides,
  fixed air, of all others, is the most readily absorbed; and, indeed,
  if we could admit of absorption of any basis of air in the present
  case, it certainly ought to be that of fixed air; but where such a
  quantity is thrown out, we cannot well admit of any absorption.

5. That, during the circulation, the blood charges itself with carbonic
hydrogen air, is an assertion which cannot be easily admitted. It has
already been observed, that, by the air-pump, venous blood does not
appear to contain any elastic fluid whatever; and it is also certain,
that animals cannot bear any quantity of air injected into their veins.
Dr. Girtanner himself tried several kinds, and all of them proved
fatal. Having injected a considerable quantity of oxygen air into
the jugular vein of a dog, the animal raised most terrible outcries,
breathed very quickly, and with the utmost difficulty; by little and
little his limbs became stiff, he fell asleep, and died in less than
three minutes. On injecting into the vein of another dog a small
quantity of phlogisticated air, the animal died in twenty seconds.
With carbonic acid gas (fixed air) a third dog died in a quarter of
an hour. A fourth was killed in six minutes by nitrous air.[73] From
these experiments, had no others ever been made on the subject, it
seems very probable, that no species of air can be safely admitted
into the blood in its elastic state. If any such therefore should
naturally be produced in the body, it must either be instantly thrown
out, or disease must ensue. Such objections to the Doctor’s theory
are so natural, that we might have thought he would have foreseen and
provided against them. Instead of this he grounds the whole upon such
slender evidence as could not be admitted in the most trifling matter.
“An incision (says he) was made in the jugular vein of a sheep, and
the blood which came from it was received into a bottle filled with
nitrous air. When the bottle was half filled, it was closed. The
blood coagulated immediately, and a separation of a great quantity
of blackish serum took place. The day after, on opening the bottle,
a very strong smell of nitrous ether (dulcified spirit of nitre) was
perceived, the nitrous air having been changed in part into nitrous
ether by the carbonic hydrogen gas of the blood. This experiment
proves, beyond a doubt, that the venous blood contains carbonic
hydrogen air; and that this air is not very intimately mixed with it,
but may be expelled with the greatest ease.”

  [73] Nitrous air is that suffocating vapour which arises when aqua
  fortis is poured upon metals. When taken into the lungs it destroys
  animal life more quickly than any other species.

On reading the Doctor’s account of this experiment; it must be very
obvious, that, however decidedly he may be of opinion that it proves
_beyond a doubt_ the existence of hydrogen air in the venous blood,
yet there is not one solid reason; from what he says, for supposing
any such thing. How can any man determine from the mere _smell_ of
_sheep’s_ blood taken out of the body of the animal, and mixed with
a poisonous vapour, what is the composition of _human_ blood in the
living body? In the case of any substance suspected to contain elastic
air, the air-pump will always afford an _experimentum crucis_. But we
know that venous blood does not yield any elastic vapour by the pump:
if instead of blood, however; we should fill a portion of vein with
beer, cyder, or other fermented liquor, it would instantly discover,
by its swelling up, that it really contained air in an elastic state.
If then from the tumefaction of the vein when filled with fermented
liquor we conclude that the latter contains fixed air, why should we
not, from the non-tumefaction of it when filled with blood, conclude
that the vital fluid contains no air? If Dr. Girtanner was so well
assured that the venous blood contains hydrogen air, he ought to have
expelled some of it from a portion of the blood, noted the difference
between the blood which had lost its air, and that which had not, and
then, by adding the air to it again, restored the blood to its former
state. Nothing less then recomposition can prove the truth of a
chemical analysis; as division can only be proved by multiplication, or
multiplication by division.

From all that has been said, we may fairly conclude, that no proof can
be brought sufficient to prove the existence either of oxygen air or
any other species of aerial fluid, in its elastic state, in the blood.
Neither can we prove that any part of the condensable part of oxygen
air is received by the breath in the lungs. It is, however, probable
that this condensable part may be received into the stomach with our
food; that having passed through the various channels of circulation,
and arrived at last at the surface, it there resumes its aerial nature
by combining with the superfluous heat of the body, and is evaporated
through the pores of the skin by insensible perspiration. The aerial
vapour which passes off by these pores indeed has been discovered to
partake of the nature of _fixed air_; but we know that this species
of gas always contains the basis of oxygen, being indeed composed of
it; and whether the oxygen be taken into the body in its pure state
or not, the result would undoubtedly be the same; for an union would
be formed between it and the carbonic particles to be thrown off from
the body. But thus we can never suppose the basis of oxygen or any
other air to be a permanent part of the composition of our bodies; nor
can the quantity of it be augmented by breathing any kind of air. The
readiest way to increase the quantity seems to be by drinking fermented
liquors. Thus, if the body is too hot, the superfluous heat will have
a proper subject to act upon, viz. the condensable part of the fixed
air; and hence we may perhaps account for the very grateful and cooling
sensation produced by drinking these liquors in some diseases. With
respect to the existence of _carbon, charcoal_ or _hydrogen_ in the
blood, it is probable that it exists in equal quantity at all times,
being indeed the fundamental material of the whole body, and probably
only a modification of that _dust_ from whence man was originally
taken.[74] When the blood therefore grows very black, when the teeth
are covered with a black sordes, the hands become foul, &c. we may say,
indeed we too surely _feel_, that, in such cases, there is a propensity
in the body to return to its original state of dissolution; but there
is not one solid reason for supposing the proportion of its materials
to be varied; that there is a collection of _oxygen_ in one part,
_hydrogen_ in another, or in short that nature can admit of any such
disproportion taking place.

  [74] In one of Dr. Priestley’s papers above quoted he says, that
  _charcoal_ is entirely of _vegetable_ origin; but the conversion of
  vegetable into animal matter which we daily see is an undoubted proof
  that there cannot be any essential difference between them. Even the
  bones are undoubtedly produced from vegetables in such animals as
  feed upon vegetable substances; so that even the calcareous earth
  they contain is plainly of vegetable origin. We may say indeed that
  the calcareous particles had a previous existence in the vegetables
  used by the animal as food; but we may say the same of the particles
  of the blood, flesh, horns, &c. Besides, Dr. Priestley has shown that
  _every_ particle of charcoal may be volatilized into inflammable
  air, with as great accuracy as any human experiment can be made; so
  that in this case the calcareous particles, if any such there were,
  showed themselves to be as much charcoal as the rest. In the 74th
  volume of the Philosophical Transactions, Mr. Watt has shown, that
  dephlogisticated spirit of nitre may be changed into the smoking and
  phlogisticated kind by means of red-lead or magnesia alba, as well
  as by charcoal; of consequence there can be no essential difference
  even there. In short, so wonderful and multifarious are the
  transforming or metamorphosing powers of nature, that every attempt
  to find out a substance upon which these powers cannot act, will be
  found altogether vain, and our best conducted and most plausible
  experiments, made with a view to discover the ultimate composition or
  what we call the elements of bodies, will be found mere inaccuracy,
  bungling and blunder.

6. We must now consider Dr. Girtanner’s account of the origin of
animal heat, which is, that, “during the distribution of the oxygen
through the system, the heat which was united with this oxygen
escapes; hence the animal heat;” and, “that the great _capacity_
of the arterial blood for heat is owing to the oxygen with which
it is united in the lungs.”--This leads us to consider in a more
particular manner the doctrine of heat, a subject hitherto much less
investigated than the importance of the subject requires. What little
we do know of this matter seems to be almost entirely owing to Dr.
Black, who hath discovered some very remarkable phenomena unknown to
former philosophers. His discovery here, as in that of fixed air, was
accidental. Making experiments on the water of different temperatures,
he found that the mixture would always be an arithmetical mean betwixt
the two quantities mixed. Thus, on mixing water at 50 degrees with
an equal quantity at 100, the temperature of the mixture would be 75
degrees; but if instead of using water only he took snow or ice for
one of the quantities, the mixture was no longer an arithmetical mean
betwixt the two temperatures, but greatly below it; so that a quantity
of heat seemed to be totally lost and in a manner annihilated. His
attention was engaged by this unexpected phenomenon, and, prosecuting
his experiments, he found that, when water was converted into ice, it
really became warmer than it was before; and, by keeping the fluid
perfectly still during the time that cold was applied, he was able
to cool it to 27 degrees of Fahrenheit’s thermometer, which is five
degrees below the freezing point; but on shaking this water so cooled,
it was instantly converted into ice, and the thermometer rose to 32. On
reversing the experiment he found that mere fluidity in water is not
sufficient to melt ice. A considerable degree of heat is necessary;
and even when this is previously given to the water, the whole becomes
as cold as ice by the time that the ice is melted. The result of his
experiments in short was this: Water, when frozen, absorbs an hundred
and thirty-five degrees of heat before its fluidity can be restored:
that is, supposing a pound of ice at the temperature of 32 to be mixed
with a pound of water at the temperature of 32, by adding 135 degrees,
so that the temperature of the water is augmented to 167, the ice will
indeed be melted, but the temperature of the whole quantity of liquid
will be reduced to 32. In this case therefore the heat manifestly
assumes two different modes of action: one in which it acts internally
upon the substance of the body, without being sensible to the touch,
while in its other state it hath no effect upon the internal parts, but
affects bodies on the outside. The former state therefore the Doctor
distinguished by the name of _latent_, the latter by that of _sensible_
heat.

The same theory was applied to explain the doctrine of evaporation, and
that in the most decisive and satisfactory manner. The Doctor found,
that, in the distillation of water, much more heat was communicated
to that in the worm-tub of the still, than could be supposed necessary
to raise the water distilled to 212 degrees, which is the utmost that
water can bear. In prosecuting the experiment he found the quantity of
heat absorbed by the water, when raised into vapour, truly surprising;
no less than _a thousand_ degrees; an heat more than sufficient to
have made the whole quantity of fluid that came over red hot. Some
objections, however, were made to this theory, even by the Doctor’s
friends. Mr. Watt, particularly, though he could not deny the theory
derived from Dr. Black’s experiments, yet suggested one, which, had
it proved successful, would have overthrown the whole. It was this:
Let water be distilled _in vacuo_, where it boils with a heat of 97
degrees, and the operation must be carried on with much less fuel, and
with much greater ease, than in the common mode. It was said that, in
this experiment, Dr. Black was equally concerned with Mr. Watt; but,
in a personal conversation with the Doctor himself, he assured me
that he had no farther concern than foretelling that the experiment
would not succeed, which it seems did not. The event was as follows:
Mr. Watt, determining at all events to try the experiment, caused to
be made a copper retort and receiver, joined together in one piece.
In the receiver he pierced a small hole, and, heating both retort and
receiver, plunged the latter into cold water. The consequence was,
that a considerable quantity of water entered the vessel, and was
easily poured back into the retort, as a subject for distillation. A
fire being now applied, the water was soon raised into steam, which
filled both retort and receiver, and in a great measure expelled the
external air. The small orifice in the receiver being now closed, and
the receiver itself plunged into cold water, the distillation went
on _in vacuo_; for, as soon as any of the steam was condensed, the
space which it had occupied (according to Dr. Black _one thousand and
sixty-six_ times more than the original water) was become absolutely
empty, and more steam, rarefied, not by any quantity of sensible heat,
but merely by that which it contained in a _latent_ state, would occupy
the place of the former. The event of the experiment showed the truth
of Dr. Black’s theory. The water boiled, and steam was raised as well
as if access had been given to the air; but with this difference,
that the upper part of the distilling vessel was never heated above
what the hand could easily bear. With the water in the cooler it was
quite otherwise. It became hot as usual, and, by the quantity of heat
it received, plainly demonstrated that the vapour, though destitute
of most of its _sensible_ heat, yet contained an immense quantity in
a _latent_ state. The saving of fuel therefore in the practice of
distillation, which was Mr. Watt’s object in making the experiment, was
quite trifling, and not equal to the trouble of filling the retort with
liquid.

The doctrine of latent heat thus established, furnished a solution of
many phenomena which could not formerly be explained in a satisfactory
manner. Thus the melting of all kinds of substances was found to be
owing to an absorption of heat, while their condensation was attended
with the contrary. Fluidity in all cases was explained on the same
principle; and the more heat that was absorbed, the more fluid the
matter became. Thus water, when in a condensed or solid state, absorbs
135 degrees of heat before it becomes fluid. A thousand degrees more
convert it into vapour, and at last, by passing through the intense
heat of a glass-house furnace, it is converted into a brilliant
flame, and augments the heat of the furnace to a great degree. Hence
the practice in glass-houses of throwing water into the ash-hole,
the vapour of which, by passing through the burning fuel, makes the
furnace much hotter than it was. In a similar manner were explained
the phenomena of crystallization, the ductility of metals, the heat
produced by hammering them, and the hardness produced by the operation,
as well as the operation of annealing, &c. One other phenomenon, a very
curious one, shall be noticed, on account of its being connected with
the subject of this treatise. It is this: Let a small vessel filled
with vitriolic ether be put into a larger one of water, and both
included in the receiver of an air-pump. On exhausting the air, the
ether boils, and is converted into vapour, while the water freezes.
This shows that heat does not always act equally upon surrounding
bodies, but has a tendency to enter some in preference to others;
and from other experiments it appears, that this property has a
considerable connexion with the density of the bodies concerned.

Thus one step was gained, and it was universally admitted that heat,
in some cases, entered bodies, and in others was thrown out of them;
but now the question arose, What is heat; and by what laws is it
regulated, or from what source is it derived? Here Dr. Black himself
was at a loss; for, as he supposed _cold_ to be a mere non-entity,
and only to consist in a comparatively smaller degree of heat, some
phenomena occurred which would not easily admit of solution upon such
an hypothesis. With these Dr. Black did not meddle much, but others
were bolder. Dr. Irving, Professor of Chemistry at Glasgow, undertook
to explain the whole mystery of latent heat upon the single principle
of attraction. One of the most puzzling phenomena in the way of Dr.
Black’s theory had been, that in some cases heat and cold seemed to
repel each other, and a very remarkable instance of this was, that,
in the morning, a little before sunrise, when the rays of light pass
through the atmosphere, a little above the surface of the earth, the
air then becomes manifestly colder than even at midnight. Dr. Irving’s
explanation of this was, that the sun’s rays _attracted heat from
the atmosphere_, and thus rendered it colder. Such at least was the
explanation given in an inaugural dissertation by Dr. Cleghorn, one of
Dr. Irving’s scholars; for the Doctor himself delivered his opinions
only to them. In other cases he supposed that different substances
had different _capacities_ for receiving heat; and, of consequence,
should the _form_, or rather the _internal constitution_, of the body
be changed, the _capacity_ of it for receiving heat must also be
changed; and as an attraction subsists, or is supposed to subsist,
between heat and all other substances, it is plain that while this
attraction subsists, if the capacity of any substance for receiving
heat be augmented, it will imbibe much more than it would have done
had its former constitution remained. Thus _water_ in its liquid state
contains a certain quantity of heat; we may therefore say that water
has a capacity for receiving heat equal to one to ten, or what we
please. Vapour has a capacity for containing heat ten times greater
than water. Water therefore, when converted into vapour, will imbibe
ten times the quantity of heat that the water contains; and, again,
on being re-converted into water, the _capacity_ becoming what it was
before, the superfluous quantity must be thrown out, as in Dr. Black’s
experiments. In like manner, when a metal is melted by the fire, the
capacity of it for receiving heat is changed: of consequence a great
quantity is imbibed, and again expelled by the change of _capacity_
which takes place on its becoming solid; and thus, from the change of
capacity, in different substances, every phenomenon was solved.

This doctrine of _capacities_ did not give general satisfaction.
Dr. Black himself said of it, that it was neither _probable_ nor
_ingenious_;[75] notwithstanding which, it continued to be received,
and even very generally adopted. Dr. Crawford, so well known for his
writings on this subject, has adopted the idea, and Dr. Girtanner, in
the passage above quoted from him, appears to be of the same opinion.
The doctrine, however, had several opponents, among whom were the
Monthly Reviewers. In their account of Nicholson’s First Principles
of Chemistry, they express themselves in the following manner: “We
only wish, that, in the doctrine of heat, he had avoided, which he
might easily have done, Dr. Crawford’s idea of bodies having different
_capacities_ for heat. In the melting of ice, for instance, a quantity
of heat is absorbed, without any increase of the temperature, that
is, without making the water sensibly warmer than the ice before its
liquefaction; which is said to be owing to the water having a greater
_capacity_ for heat, or being able to _hold more_ of it, than the
ice; and, in like manner, when converted into vapour, its capacity
is further increased, or it can hold more still. This appears to us
a very unchemical, and a very inadequate idea of the matter: for,
admitting water to have a greater capacity than ice, how is the change
from one state to the other to be effected? Can the properties which a
body is found to possess, after a change has taken place, be assigned
as a cause of the change itself? Or will it be said, that the heat
first enlarges the capacity, and then hides itself in that capacity
so enlarged? We should think it much better to say, consonantly with
the phenomena of other combinations in chemistry, that a certain
quantity of heat, uniting with the ice, first _liquefies_ it, as a
certain quantity of acid only neutralizes an alkali; that if any
surplus quantity must be introduced, that surplus, remaining free and
uncombined, must act and be sensible as heat in the one case, and
acid other; and that different bodies require different quantities of
heat or acid to be combined with them, for producing the changes in
question.”[76]

  [75] These words are to be found in the M. S. Copies of his lectures
  circulated at Edinburgh. Dr. Black himself never published any thing
  to the world upon the subject.

  [76] Monthly Review, for 1790, p. 165.

Thus the Reviewers, as well as others, reasoned _a priori_, and several
facts were adduced to prove that no such changes in capacity could take
place. But however strong the arguments adduced, or however plain the
experiments might be, little or no notice was taken of them, and the
enlargement or diminution of _capacities_ has been repeated, seemingly
by rote, from one author to another, without the least inquiry or
investigation. Dr. Girtanner indeed says that “the oxygen united with
the arterial blood in the lungs” is the cause of the _great capacity_
of the arterial blood for heat. But this is assigning a very doubtful
cause for a very doubtful effect. He ought to have proved in the
first place that arterial blood really has this capacity; for its
being _hotter_ than the blood of the veins, only shews that it parts
with more heat to surrounding bodies than venous blood does; which
is a proof that it contains _less_ heat, if there be any difference,
than that of the veins. But the truth is, that the _capacity_ for
containing heat depends neither on the oxygenation nor hydrogenation
of a fluid, but upon its density. The more fluid and the more easily
expansible into vapour that any substance is, the greater quantity
of heat it is capable of containing, and _vice versa_. This has been
fully ascertained by Mr. William Jones, an English clergyman, whose
observations on the generally received system of philosophy contain
many particulars worthy of attention. From his experiments it appears
that a piece of red-hot iron, thrown into water, imparts much less
_sensible_ heat to it, and is itself much more effectually quenched,
than by throwing it into an equal quantity of quick-silver of the same
temperature with the water. As the quick-silver therefore becomes much
hotter to the touch than water does upon throwing a piece of red-hot
iron into it, and as the iron itself is much more imperfectly quenched
by the metal than by the water, it follows that the latter is capable
of containing much more heat than the former. But such experiments
are not applicable to the blood. Though that of the arteries may be
somewhat hotter than the venous blood, yet the reason is obvious. The
heat is communicated directly to the arterial blood in the lungs; but
during the circulation a part of it evaporates, and the farther distant
any part is from the lungs, the more cool will the vital fluid be,
without regard to any alteration of _capacity_, which indeed never can
be shown to exist.

But the most decisive experiments against any supposed alteration in
the capacities of bodies for containing heat are those lately tried
by Count Rumford, and related in the Philosophical Transactions for
1798. His attention to this subject was engaged by observing the great
degree of heat acquired by a brass gun during the time of boring
it,[77] and still more by the intense heat (much greater than that of
boiling water) of the metallic chips separated from it by the borer.
From a consideration of these things he was naturally led to the
following inquiries. “Whence comes the heat actually produced in this
mechanical operation? Is it furnished by the metallic chips which are
separated by the borer from the solid mass of metal? If this were the
case, then, according to the modern doctrine of caloric, the _capacity
for heat_ of the parts of the metal so reduced to chips, ought not
only to be changed, but the change undergone by them be sufficiently
great to account for _all_ the heat produced. But no such change had
taken place; for I found, that by taking equal quantities by weight of
these chips, and of thin slips of the same block of metal, separated
by means of a fine saw, and putting them at the same temperature, that
of boiling water, and putting them into equal quantities of cold water
(that is to say, at 59-1/2 of Fahrenheit) the portion of water into
which the chips were put, was not, to all appearance, heated either
less or more than the other portion in which the chips were put.”

  [77] Count Rumford was superintendant of boring the cannon in the
  workshops of the military hospital at Munich.

From this experiment, several times repeated with the same result,
Count Rumford inferred, that the heat could not possibly have been
furnished at the expense of the latent heat of the metallic chips. He
then proceeded to ascertain “how much heat was actually generated by
friction, when a blunt steel borer being so forcibly shoved (by means
of a strong screw) against the bottom of the bore of the cylinder,
[of the machine in use] that the pressure against it was equal to
the weight of about ten thousand lb. avoirdupois, the cylinder being
turned round on its axis (by the power of horses) at the rate of about
thirty-two times in a minute.” In this experiment the metallic dust
or scaly matter detached from the cylinder by the borer weighed only
837 grains troy; but, says the author, “Is it possible that the very
considerable quantity of heat produced in this experiment (a quantity
which actually raised the temperature of above 113 lb. of gun-metal
at least 70 degrees of Fahrenheit’s thermometer, and which of course
would have been capable of melting 6-1/2 lbs. of ice, or making near
five pounds of ice-cold water to boil) could have been furnished by
so inconsiderable a quantity of metallic dust, and this merely in
consequence of a _change_ of its capacity for heat? As the weight of
this metallic dust (837 grains troy) amounted to no more than one
948th part of that of the cylinder, it must have lost no less than
948 degrees of heat to have been able to raise the temperature of the
cylinder one degree; and consequently it must have given off more than
_sixty-six thousand, three hundred and sixty_ degrees of heat to have
produced the effects which were actually found to have been produced in
this experiment.”

It was next considered whether the air did not contribute to the
generation of this heat; and our author determined that this could not
be the case; because the quantity of heat generated was not sensibly
diminished when the free access of air was prevented. From another
experiment it appeared that the generation of the heat was neither
prevented nor retarded by keeping the apparatus immersed in water. Here
the friction generated so much heat, that in one hour the temperature
of the water surrounding the cylinder was raised from 60 to 107 degrees
of Fahrenheit. In half an hour more it was raised to 142; at the end
of two hours to 178; at two hours 20 minutes to 200; and in two hours
and a half it boiled.[78] On the whole, Count Rumford concludes, that
“the quantity of heat, produced equably by the friction of the blunt
borer against the bottom of the hollow metallic cylinder, was _greater_
than that produced equably in the combustion of _nine wax candles_,
each three quarters of an inch diameter, all burning at the same time
with a clear, bright flame.” From all these experiments, however, our
author does not draw any certain conclusion. “What is heat? (says he.)
Is there any such thing as an _igneous fluid_? Is there any thing that
can with propriety be called _caloric_? The heat produced, in the
author’s experiments, by the friction of two metallic surfaces, was
not furnished by small particles of metal, detached from the larger
solid on their being rubbed together. It was not supplied by the
air, because the machinery in three experiments was kept under water,
and the access of atmospherical air completely prevented. It was not
furnished by the water which surrounded the machinery, because this
water was continually receiving heat from the machinery and could not
at the same time be giving to and receiving heat from the same body;
and because there was no chemical decomposition of any part of this
water.” At last he observes, that the source of this heat, whatever it
is, must evidently be inexhaustible, adding, that “any thing, which
any _insulated_ body, or system of bodies, can continue to furnish
_without limitation_, cannot possibly be a _material substance_; and
it appears to me to be extremely difficult, if not quite impossible,
to form any distinct idea of any thing capable of being excited and
communicated, in the manner the heat was excited and communicated in
these experiments, except it be MOTION.”

  [78] The quantity was two gallons and a quart, wine measure.

On this last paragraph, however, it is obvious to remark, that the
whole force of the argument rests upon an _insinuation_, that the
cylinder and borer were _insulated_, or cut off from all communication
with any other material substance. Had this been the case, then no
doubt it would follow that an _endless_ supply of any thing _material_
could not be furnished by them; but if, as Dr. Boerhaave and many other
learned and intelligent persons have supposed, fire be an element
universally present, and which becomes sensible to the touch only in
consequence of a particular mode of action, it will follow, that no
substance in nature can be _insulated_ with respect to it; but, in
whatever place, and for whatever length of time, any substance shall
be affected in such a manner as to agitate this fluid, there we shall
perceive a production of heat _without limitation_, even though heat
itself be no more than the action of a fluid essentially _material_,
though invisible to us.

Considerations of this kind occurred long ago to the writer of this
treatise, when by the nature of his employment it was necessary for
him to speculate upon these subjects. It could not then but appear
to him that the theory of Dr. Black was far superior to any that had
been published. The opinion of those who supposed fire to consist
in the vibratory motion of the particles of solid bodies, seemed
altogether untenable. It is impossible to explain the phenomena of
heat upon ordinary mechanical principles, because, with respect to
all terrestrial substances, heat constantly appears as an _agent_,
while they are merely _passive_; and no man can explain the nature of
a cause from its effect. Thus one of the most obvious effects of heat
is _expansion_, or enlargement of bulk, in such bodies as are heated.
But if from this fact we infer that the parts of elementary fire are
repulsive of one another, our reasoning is certainly erroneous. In like
manner, when we are not sensible of heat, we are not authorised to
conclude that it is not present; for Dr. Black has demonstrated that it
may be present in very great quantity, though indiscoverable either by
our senses or by a thermometer.

But, with regard to the theory published by Dr. Black himself, it
is evident that, though one part of it rests on the solid basis of
experiment, the other is founded entirely upon hypothesis, and that too
an hypothesis which cannot admit of being proved by any experiment,
viz. that _cold_ is a mere negative, and hath no real existence in
nature. Among many phenomena which militate against this opinion, the
following experiment of M. Geoffrey seems to be the most remarkable. He
took a small bason filled with water, and set it on a support in the
middle of a large tub of water, in such a manner that the temperature
of the water in the tub might communicate itself to that in the bason.
This being ascertained by a thermometer placed in the bason, he threw
a quantity of burning coals into the tub. The effect of this, on the
supposition that cold is a mere privation of heat, ought to have been,
that the heat of the coals, communicated to the water in the large
tub, would in a short time pervade the small bason, and affect the
thermometer there. The latter would therefore rise; but instead of this
it fell several degrees before it began to rise; for which it doth
not appear that any other reason can be assigned than that the cold
is partly repelled by the heat of the coals, and therefore, entering
into the small bason of water, it causes the thermometer to sink
previous to its rising. To the same purpose we may urge the phenomenon
already taken notice of, viz. that the sun’s rays, when passing at some
distance above the surface of the earth, cool the lower part of the
atmosphere. The natural solution is, that the heat of the sun partly
repels the cold downwards; and as for the doctrine of _attracting_ heat
from the atmosphere, Count Rumford has shown that this does not happen
in a case where we might with much more probability expect it; not
to mention the violence done to the common perceptions of mankind by
supposing the sun’s rays, which are most evidently the source of heat,
to have any occasion to _attract_ heat from the atmosphere or any thing
else.

Lastly, with regard to the _capacities_ of bodies for containing heat,
the doctrine appears to involve a radical error, of such enormous
magnitude, that it is impossible to make any thing of it. This is no
less than confounding the heat which flows out from bodies with that
which they contain as an essential part of their composition, and which
they cannot emit without being changed into some other form. Thus the
capacity of aqueous vapour for containing heat, according to Dr. Black,
is 1000 degrees; yet without decomposing the vapour it would have been
impossible to have known this; for vapour is often extremely cold to
the touch, and a thermometer immersed in it will sink greatly. In
short, all that we can know about the capacity of bodies for retaining
heat is, that they either continue to absorb it, or we may continue
to force it into them, till they be reduced to vapour. It is doubtful
whether they can receive more; for from the experiment with Papin’s
digester, formerly mentioned, it appears that the additional quantity
of heat, which the water was made to receive, very quickly left it as
soon as the steam had room to expand.

But, to come to a conclusion upon this subject: If we will investigate
the nature of heat, we must do it as in other cases, viz. by making the
_igneous fluid_, _caloric_, or what we please to call it, the object of
our senses; for we cannot reason fairly, or indeed come to any rational
conclusion at all, by doing otherwise. In this investigation it is
necessary to attend to the particulars mentioned by Count Rumford. The
fluid must be omnipresent in its nature, infinite in its quantity, and
equable, uniform and incessant in its action; as far as these epithets
can be applied to any material being. There are only two fluids which
we know that can answer to these characteristics. The one is the light
of the sun, which pervades all the celestial spaces; the other the
electric fluid, which penetrates every terrestrial substance. Both of
these produce heat, unlimited in quantity, as well as in duration,
provided their action be continually kept up. The mode in which both
produce heat is exactly the same, viz. by converging into a focus; and
the greater the quantity, the greater is the heat, and that without any
limitation either as to intensity or duration. With regard to the solar
rays, it has long been known that by concentration they would produce
heat; nevertheless it was unaccountably doubted whether the rays
themselves were the matter of heat. One objection to this was, that on
the tops of high mountains the air is exceedingly cold, though the sun
shines very bright. But this objection was founded upon an erroneous
notion that, wherever the matter of heat exists, there we must feel it;
which doth not follow any more than that wherever air exists there we
must feel a wind blowing upon us. _Wind_ is air in motion, and _heat_
is a more subtile fluid in motion. One demonstration of this is, that,
on the tops of the highest mountains, a burning lens or mirror will
set fire to combustible bodies as readily as in the vallies at the
foot of them. Neither has heat, properly so called, anything to do
with air. The focus of a burning-glass will heat bodies _in vacuo_ as
well as in the open air; and Sir Isaac Newton has observed, that if a
thermometer be included in the vacuum of an air-pump, it will acquire
the temperature of the room nearly in the same time that another will
when included in a similar glass without any exhaustion.

The science of electricity is but of late date; and most violent and
hypothetical disputes have taken place concerning the nature of the
fluid. Its luminous and burning properties naturally led a number of
people to suppose that it was elementary fire; but this was opposed by
others with as much violence as if there had been something criminal
in the supposition. The opposition, however, was founded upon the same
error with that about the solar light. It was imagined that wherever
elementary fire existed, there heat must be felt; and it was especially
urged, that electricity, though it produced light, did not produce
any heat, except when it exploded with such violence as to penetrate
the internal substance of bodies, agitating their particles, and by
this agitation producing heat. It has now, however, been found, that
the electric _aura_, as it is called, when made to converge in great
quantity to the point of a needle, will heat it to such a degree as
to set fire to gun-powder. This shows that heat is occasioned by the
convergence of this fluid to a focus, and to its divergence from it. In
the focal point, heat will always take place. From the experiments of
Hauksbee, Beccaria and Priestley, it likewise appears, that electricity
will render transparent the most opaque bodies, such as sealing-wax,
pitch, &c. which even the most intense light of the sun cannot do. As
to the intensity of the heat produced by it, experiments have shown,
that it cannot be exceeded even by that of the most powerful mirror.
Globules of gold have been vitrified, platina melted, and the most
infusible substances reduced to glass, by means of the electric shock.
From so many evidences, therefore, it appears to me impossible to
conclude otherwise than that the light of the sun and the electric
fluid are the same thing; and, according to the different modes in
which they act, they produce the phenomena of heat and light in all
their varieties, besides a multitude of other effects of which we
cannot have any perception. We may indeed, if we please, suppose that
some other thing exists which is heat itself, and that the light or
electric fluid sets in motion, attracts, repels, or acts otherwise upon
this unknown something; just as it comes into our heads to fabricate
our system. But, until our senses can discover in some way or other
this hidden substance, _reason_ will always suggest that it has no
existence. We may say that without such a supposition we cannot solve
the phenomena of heat. But do we ever expect to solve these phenomena;
or do we know all that the solar light and electric fluid can perform?
If we do not know what they _can_ do, neither do we know what they
_cannot_; and the invention of other fluids must be accounted not only
chimerical but useless.

But, to be more particular: on the subject of heat people have
embarrassed themselves more with philosophical reveries than by any
real difficulty, and rendered the matter more obscure than nature
has made it. We have already observed, that by the convergence of
light, or of electricity, heat is always produced. Here we can see the
mode in which the fluid acts, viz. first by _converging_, and then
_diverging_. When the light falls upon a solid body, it is evident,
that if it be allowed to flow out as easily as it flows in, no internal
agitation of the parts, or of any fluid contained in them, can take
place. Transparent bodies therefore are never heated. Again, if the
light be not allowed to enter the substance of a body, but is entirely
reflected, the body cannot be heated; and hence it is very difficult
to melt a polished metal even by a strong burning-glass. M. Macquer’s
burning mirror, which vitrified flints, could not melt silver. But,
when the light falls upon a body capable of allowing it to enter its
substance, at the same time that it cannot get out without difficulty,
it is plain that the force of the fluid will be exerted in order to
overcome that difficulty; the body will be expanded in all directions;
the fluid will be thrown out in the same manner, and the more that
the internal action of the light prevails over that power by which
the parts of the body cohere, the more will the phenomena of heat be
perceptible.

Again, let us suppose that the etherial fluid enters the substance of
any body capable of being dilated to a great degree, it is equally
plain that the action of the fluid must for some time be directed only
upon the internal parts, and consequently will be imperceptible on the
outside. This then is called _latent_ heat; and where the pressure on
the outside balances that on the inside no heat will be perceptible
to the touch. But by whatever means this balance is broken, heat will
instantly be perceptible; and experiments show that the balance may
be broken either by an increase of cold or heat. Thus, in the case
of water, the internal pressure remains equal to the external, until
the fluid is cooled to a few degrees below 32. The balance is then
broken, and the internal action prevails; a quantity of what is called
_sensible_ heat escapes, and the water is converted into ice. Again, at
the temperature of 32, little or none of the water evaporates; but by
the addition of heat, by which the internal action of the subtile fluid
we speak of becomes greater than the external, the water is converted
into vapour; and it is remarkable that the same effect takes place on
greatly augmenting the degree of cold; for the evaporation from ice,
even in frosty weather, is found to be very considerable.

On the whole, from innumerable experiments it appears, that there
exists in nature a certain invisible fluid, by the action of which,
when diverging from a centre, heat is produced in the central point.
By a certain other power this diverging force is limited, so that in
some cases it is not perceptible beyond the surface of the body in
which it acts, and then it is called _latent_ heat. In other cases
it is perceptible in a certain degree, and the degree in which it is
perceptible hath been called the _temperature_ or _sensible heat_
of the body. On mixing different substances together it is found,
that very often the proportions between the external and internal
actions are varied. This has been already observed, when giving an
account of Dr. Black’s discovery of _latent_ heat, viz. that when
snow and warm water are mixed together the temperature of the mixture
differs very considerably from the arithmetical mean between the
temperatures of the two substances employed. Dr. Crawford prosecuted
the experiment further, and found that there were few substances
which, on being mixed, did not shew a temperature different from
that of the arithmetical mean between the temperatures of the two
originally employed. This difference he unfortunately used as the
foundation of a rule for determining the _capacities_ of different
substances for containing heat, and upon this erroneous principle has
raised a superstructure, which upon no occasion can be of service to
science, but must always produce obscurity and confusion wherever it is
introduced.

With regard to the power which sets bounds to the expansion of the
fluid acting as heat, it is natural to think that it can be no
other than the same fluid acting in a contrary direction, or from a
circumference towards a centre; and thus we shall always find that the
same fluid, by limiting its own operations, may produce those phenomena
which have been hitherto deemed so difficult of explanation. In what
manner this limitation is in all cases effected, or indeed in any
case, we cannot pretend to explain. It is sufficient to observe, that
wherever there is a perpetual _efflux_ of any thing, there must be
also a perpetual _influx_ at the same time, and in proportion to the
one the other will be. These two are directly contrary to one another,
and, as we suppose the fluid to be universal, it is evident, that if
any part of it be put in motion in a particular direction, the rest
will press towards that part where the motion is, in order to keep up
the equilibrium. Hence we may easily account for the heat produced by
percussion or by friction. By hammering a piece of iron, as Dr. Black
justly observes, the fluid is forced out from between the parts of the
metal. The emission of this fluid in all directions is heat itself;
and no sooner is one quantity thrown out than another supplies its
place with great rapidity, and so on, until the pressure of the rest in
some way or other counteracts the emission of any more, and the heat
ceases. Just so with friction. The heat produced by it is always in
proportion to the pressure employed. By this pressure the parts of the
two substances are forced into such close contact, that an agitation
and emission of the fluid pervading their substance takes place. This
agitation, as we have already noticed, is heat itself, and, as long as
the friction is continued, more and more heat will be produced, without
any limitation, as Count Rumford has observed.

Some bodies have a greater disposition than others to emit this subtile
fluid; and these we say are naturally of a warmer temperature than
others. The _temperature_ is nothing else than the efflux of the fluid
from them, continually kept up by the action of the surrounding fluid.
By mixture with different substances the temperatures of various bodies
may be changed; by some the influx, and by others the efflux, may be
augmented. In the former case we say the body becomes colder, in the
latter hotter, than before; and in not a few cases the agitation of
the fluid becomes so great that the matter actually takes fire. In all
these cases, however, we can discover nothing more than the bare fact,
that so and so is the case. We know that the bodies do grow hot by the
convergence of the etherial fluid towards them, and its emission from
them; but why it should converge or diverge we know not.

Thus much with regard to heat in general. We must next consider another
fluid which has very generally been accounted the source and fountain
of heat, viz. _air_. This is indeed so much the source of heat in all
our operations, that it was natural to think it the only one; but
experiments have now determined that air itself is a mere creature of
heat and light;[79] for, by employing these in a proper manner, airs
or gases of all kinds have been produced. Thus, by exposing water in a
glass vessel for some time to the rays of the sun, a quantity of very
pure oxygen air may be obtained; by concentrating the sun’s rays upon
charcoal, inflammable air may be had; and by distilling, with a strong
heat, substances of various kinds, we may obtain a great variety of
aerial vapours. From all this we may reasonably conclude that heat,
attached to some other substance, dissolved in it in such a manner as
to become invisible, forms the substance of air. Heat therefore being
the agent in the composition of air, it is reasonable to suppose that
it is the agent in its decomposition also, or in its transformation
from one species to another, of which the conversion of oxygen into
fixed air by combustion is an instance. When air is taken into the
lungs the blood is warmed by the action of that invisible fluid,
which has already given elasticity to the air. In consequence of a
considerable quantity of this fluid being then converted from a latent
into a sensible state, part of the elastic principle must be lost, and
the air diminished in bulk. The reason why this must constantly take
place is, that part of the heat evaporates from the surface of the
body, during the course of circulation. Were it not so, the quantity
thrown out by the lungs would be exactly equal to that which the blood
received, and consequently there could be no diminution between the
bulk of the air expired and that which was inspired; but, on account
of the waste just mentioned, the blood must always receive somewhat
more than it gives out by the breath. Thus, while the air we breathe
continues the same, and the organization of the body is not changed,
the natural operations will go on smoothly, and health will continue;
but, as we have formerly observed, by an alteration of either of these,
disease must ensue; and we must now endeavour, from the principles laid
down, to examine the mode in which epidemic diseases, and particularly
the plague, may be produced.

  [79] Dr. Priestley thinks water is an _essential_ in the composition
  of air.

The air is so evidently connected with human life, that it has been
from the earliest ages accounted the source of pestilential diseases,
though, as none of the more obvious qualities of it, such as heat,
cold, moisture, or dryness, appeared to be connected with them, they
were generally supposed to proceed from the action of some unknown
natural cause, or from that of the Deity himself. Some, however, have
also been of opinion that plagues might originate from the obvious
qualities of the air in conjunction with certain effluvia from putrid
vegetable or animal bodies. Thus, in several plagues mentioned in
ancient history, we find swarms of dead locusts, grasshoppers, the
carcases of those slain in battle, crowded houses, and filth of all
kinds, assigned as causes. This opinion was adopted by Dr. Mead,
and he gives the following account of the origin of the plague in
Egypt. “Grand Cairo is crowded with inhabitants, who for the most
part live very poorly and nastily; the streets are narrow and close;
it is situate in a sandy plain, at the foot of a mountain, which, by
keeping off the winds that would refresh the air, makes the heats very
stifling. Through the midst of the city passes a great canal, which is
filled with water at the overflowing of the Nile; and, after the river
decreases, is gradually dried up: into this canal the people throw all
manner of carrion, filth, &c. so that the stench which arises from
this and the mud together is insufferably offensive. In this posture
of things, the plague every year preys upon the inhabitants, and is
only stopped when the Nile, by overflowing, washes away this load of
filth; the cold winds, which set in at the same time, lending their
assistance by purifying the air.” He then proceeds to account for the
plagues in Ethiopia in the manner above related, viz. by the prodigious
swarms of locusts, which sometimes occasion a famine by devouring the
fruits of the earth, and, when they happen to be cast by the winds
into the sea, occasion a pestilence; the putrefaction being heightened
by the intemperance of the climate, which here is so great that it is
infested with violent rains for three or four months together; and
it is particularly observed of this country, that the plague usually
invades it whenever rains fall during the sultry heats of July and
August. He next takes notice of what the Arabians say of the origin
of the plague in Ethiopia, viz. that it is brought on by unseasonable
moistures, heats, and want of winds. But, whatever truth may be in the
account given of the Ethiopic plagues, the testimonies already produced
in this treatise are sufficient to render it very doubtful, at least,
whether the plague ever does originate in Cairo, or any other place
in Egypt. Besides, if we once admit the existence of any thing as a
cause adequate to the production of a certain effect, wherever that
cause exists the effect ought certainly to follow, unless where we
plainly perceive something which prevents its action. It is not fair
reasoning to say that the action of the cause is prevented by something
unknown, for we might as well say that this unknown something is the
cause originally, and acts only upon certain occasions, of when it
thinks proper. Now, if the filth of the canal of Cairo be the cause of
the plague in that city, it ought to recur annually at the season when
that filth exists in greatest quantity, and in the most putrid slate.
Nevertheless we have the express testimony of Mr. Eyles Irwin, that at
the time he was in Cairo there had not been any plague for seven years.
The account he gives of it is a kind of contrast to that above quoted
from Dr. Mead. “_Misir al Kaira_, says he, or the _City of Anguish_, so
called from the frequent visits which it has received from the plague,
but commonly called _Grand Cairo_ by us, is situated in lat. 30 degrees
3 minutes N. on an artificial branch of the Nile. Old Cairo nearly
faces the river; but the new city is removed above a mile from it, and
approaches to the range of mountains which runs through Upper Egypt,
and abruptly breaks off here. It is undoubtedly one of the finest
cities in the east; which, from the present style of architecture that
reigns among the orientals, is but a faint commendation. The houses
are in general built of stone, and, being elevated to several stories,
would make a grand appearance, notwithstanding the inelegance of their
structure, were not the effect destroyed by the excessive narrowness
of the streets. This is one of the causes to which the ingenious Dr.
Mead ascribes the birth of the plague in this capital; but experience
evinces that it arises from _foreign and adventitious_ causes. _There
has not been a plague here these seven years_; which is rendered more
remarkable by the commencement of the Russian war at the date of its
cessation. No one can account for this; though a year seldom passed by
before without a visit from it.”[80]

  [80] Irwin’s Voyage up the Red Sea p. 335.

From this it plainly appears, that, however these putrid effluvia may
concur with other circumstances in producing the plague, they are by no
means the _only_ cause; otherwise not a single year could have passed
in Cairo without a pestilence; and the very same thing we shall find
to hold good in every other, let us choose for a cause what we will.
In order to investigate this matter fully, we must now consider what
causes have been assigned by physicians for other epidemical diseases;
and here, to avoid prolixity, we shall chiefly confine ourselves to
those enumerated by Dr. Fordyce as the causes of fever; a gentleman
whose very extensive experience must give the greatest weight to his
testimony.[81] The principal causes assigned by him are,

  [81] At the time of writing his treatise Dr. Fordyce informs us, that
  he had been “for upwards of twenty years one of the three physicians
  of St. Thomas’s Hospital (in London) whose walls have contained
  nearly four thousand patients every year, where the proportion of
  fevers to other diseases is much greater than the general proportion.”

1. _Infection_, or “a peculiar matter generated in the body of a man in
fever, which is carried by the atmosphere, and applied to some part of
the body of a person in health, and which causes fever to take place
in him.” That such a cause exists, he proves from observing that “of
any number of men, one half of whom go near a person ill of a fever,
and the other half do not, a greater number of the former will be
infected, in a short period afterwards, than in those who do not.” He
says he has known, in such circumstances, seven out of nine infected
with the disease. This infection is not discoverable by smell or any
other organ of sense; neither can the greatest attention to cleanliness
disarm it of its malignity. Of this the Doctor says that he has known
instances; nay, of a person going into a room where a feverish patient
was, and bringing with him the infection, which was communicated to
others in the room to which he came. He owns, however, that by allowing
the air to stagnate in which feverish patients are, the infection will
become extremely violent and fatal. This may naturally be supposed,
even without having recourse to putrid effluvia; because, independent
of these, the imperceptible infectious matter itself will undoubtedly
be accumulated in the atmosphere of the room, and act more powerfully
than it could have done had it been partly carried off and diluted by
attention to cleanliness and ventilation. He also says, that “when a
number of persons live in a small space, supposing even that they are
kept as clean as possible, it happens frequently that fever arises in
some, often in many of them. It has been in this case supposed, and is
extremely probable, that some peculiar species of matter is _produced_,
capable of producing fever, on being applied to the body.”

2. _Effluvia from putrid animal or vegetable matters._ Of this our
author seems to be less fully ascertained than of the former, as he
does not say that he has observed any instances of fevers arising from
this cause; and he concludes by observing that “either the cause of
fever, consisting of matter produced in the body of a person affected
with this disease, seems probably different from that produced by
putrefaction, or might be generated without any putrefaction taking
place.”

3. _Cold._ Our author “is not disposed to allow that sudden exposure to
cold occasions fever to take place, unless some symptom of the disease
follows immediately. If a man had been suddenly exposed to cold, and
continued in perfect health for _twenty-four_ hours, the author would
never allow that fever, or any other disease, was occasioned by it.
In this case (exposure to cold) the evidence is much stronger than in
that of infection; for the author (Dr. Fordyce) has seen many instances
where, from exposure to cold, the commencement of the attack was
instantaneous; and many are to be found in the records of medicine.”

4. _Moisture._ On this subject the Doctor observes, that the
application of water to the body is not a cause of fever, unless the
air has particles of water floating in it; in which case fever has
ensued more frequently than in other cases. Water may exist in the
atmosphere in three states. 1. In small drops suspended in it like
dust in water. 2. In vapour. In this case the transparency of the air
is not impaired, and a _chemical_ combination, as it is called, between
the air and water takes place. If the atmosphere be hot or dense, it is
capable of combining chemically with a larger proportion of water. If
therefore the atmosphere should in this manner be saturated with water,
at any particular degree of heat or density, by diminishing either of
these the vapour will be condensed, and the water reduced to the former
state of suspension in small particles. 3. Water, heated to the boiling
point, emits a steam, which combines chemically with the atmosphere,
till the latter be saturated, after which it assumes the form of small
particles; and _this last is the only state_ which has been found to
produce fever.

Moisture will also produce fever when applied to the body by wearing
wet clothes. Those which imbibe or part with heat most slowly, are
least apt to produce fevers on being heated. The warmer the atmosphere,
the more liable people are to fevers from moisture.

It has been observed, that moisture from marshes, stagnating canals, or
where the water runs very slowly, is more apt to produce fevers than
what proceeds from the sea, lakes or rapid rivers. “This (says the
Doctor) has given occasion to suppose that some other vapours proceed
from such marshes beside water, and produce the disease. It certainly
often happens, that a considerable degree of putrefaction takes place
in marshy grounds, and more especially in warm climates; but it is
by no means to be concluded that moisture in the atmosphere always
produces fever in consequence of putrefaction. Putrefaction can only
take place in vegetable or animal substances. If water therefore, not
impregnated with either, should be in such a situation as to produce
moisture in the atmosphere, no putrefaction can take place; therefore,
if fevers ensue, they are certainly in consequence of moisture, not
putrefaction. Many instances of this may be brought, as in the war
which took place in Flanders, between the tenth and eleventh year of
the present century, an army encamped upon sandy ground, in which
water was found in digging less than a foot deep, and occasioned a
great moisture in the air, which produced in a few days numbers of
fevers, although the army was perfectly healthy before, and no more
fevers were produced on shifting their ground. There are a vast many
other instances of the same thing having taken place. Besides, fever
has often arisen immediately in persons sitting in rooms, the floors of
which had been just moistened with pure water.”

5. _Certain kinds of food._ On this Dr. Fordyce observes, that, though
food of difficult digestion undoubtedly produces a number of diseases,
he has never seen it productive of fever excepting once. Dr. Girtanner
relates, that the emperor of Germany, having forced a number of his
subjects to serve as soldiers, and sent them into an unwholsome part
of Walachia, where he fed them with a kind of paste made of bread and
water instead of meat, many of them died of the scurvy. The Doctor,
however, does not ascribe this to any positive cause, but to three
_negatives_, viz. the abstraction of the stimulus of _nutriment_, by
feeding on the paste just mentioned; of the stimulus of _oxygen_ in the
corrupted atmosphere of Walachia; and lastly of the _nervous stimulus_,
the most powerful of all; the greatest part being engaged by force
against their will. This corroborates what Dr. Fordyce has said, that
bad food is very seldom the cause of fever; for among so many, who used
the _imperial_ paste just mentioned, some would certainly have been
affected by fevers, had it been capable of producing them; but, as it
did not, it is most evident that the deficiency of _stimuli_ is not the
cause of fever.

6. _Passions of the mind._ These are looked upon by Dr. Fordyce to
be among the less frequent causes of fever, though it is certain
that they have been productive of multitudes of diseases, and even
of sudden deaths; and Dr. Falconer, in his Prize Dissertation,
ascribes to the passions very considerable effects in fevers, and
even in the plague itself. “Contagious fevers (says he) afford
strong instances of the influence of mental affections, both as
prophylactics and remedies. The plague is a remarkable example, and
the same reasoning extends to other disorders of a febrile, contagious
nature. Fear, it is well observed by Dr. Cullen, by weakening the
body, and thereby increasing its irritability, is one of the causes
which, concurring with contagion, render it more certainly active,
which he ascribes to its weakening effect on the body, by which its
irritability is increased. Against this therefore he directs the mind
to be particularly fortified, which is best done by giving people a
favourable idea of the power of preservative means, and by destroying
the opinion of the incurable nature of the disorder, by occupying the
mind with business or labour, and by avoiding all objects of fear, as
funerals, passing-bells, and any notice of the death of particular
friends. Even charms might be used with good effect, could we promote
a strong prepossession of their efficacy, either by the confidence
they inspire, or by their engrossing the attention of the mind.
It is no less certain, that a studious regard to promote hope and
confidence in recovery, is equally necessary for the cure as for the
prevention of such disorders. We know that contagious fevers have a
peculiar tendency to diminish the energy of the brain, and of course to
debilitate the whole system; and that this is especially the case with
the plague, which produces the most considerable effects in weakening
the nervous[82] system or moving powers, and in disposing the fluids
to a general putrescency; and Dr. Cullen is of opinion that to these
circumstances, as the proximate causes of the plague, regard should
chiefly be had, both for the prevention and cure of this disorder.
It must therefore be highly necessary, during the course of this
disease, to attend to the support of the spirits, as on these the vital
principles greatly depend; and they can by no means be so effectually
kept up as by inspiring a confidence of recovery.”

  [82] “An intense head-ach, uncommon giddiness, and a sudden loss of
  strength, were the first complaints of those who were seized with
  this distemper.”

       (Russel on the Plague at Aleppo, p. 230.)

Dr. Zimmerman presents us with a great number of examples of the
influence of the passions in producing diseases, or death itself; some
of the most remarkable of which follow. “All the passions (says he)
when carried to excess, bring on very formidable diseases. Sometimes
they occasion death, or bring us at least into imminent danger. The
most reputable physicians agree in opinion that terror may occasion
apoplexy, and death; and indeed they consider apoplexy as the most
common effect of violent passion. Without being carried to excess, a
passion will sometimes occasion a difficulty of breathing, together
with a sense of stricture in the breast, and an hesitation to speak;
the tongue remaining as it were immoveably fixed on the palate.
Hysterical and hypocondriacal affections are sometimes the effects
of grief in the most healthy people. Joy is much more dangerous to
life than sudden grief. Sophocles died through joy at being crowned
on account of a tragedy he had composed in his old age. The famous
Fouquet died on being told that Louis XIV had restored him to
liberty. The niece of the celebrated Leibnitz, not suspecting that a
philosopher would hoard up treasure, died suddenly on finding under
her uncle’s bed a box containing sixty thousand ducats. Violent anger
has sometimes produced hæmorrhages and subcutaneous extravasations;
or, some vessel of the brain being ruptured by these transports, a
fatal apoplexy has taken place. There have been instances of excessive
anger being succeeded by epilepsy, colic, or a violent degree of
fever. Sometimes it has occasioned an increased flow of bile. In some
this produces vomiting; in others it goes off downwards, and causes
diarrhœa; or being retained, from a stricture of the gall-ducts, will
perhaps be absorbed, and occasion jaundice. In cases where anger has
been succeeded by extreme grief, obstructions have taken place in the
liver. The effects of terror are similar to those of anger, but in
general more violent. Sometimes excessive terror seems to give to men
a preternatural strength, as is the case with madmen and drowning
persons. In some cases it has not only excited immediate convulsions,
but caused them to return periodically. Fear has been said to make the
hair stand upright, and to contract the pores from which the hairs
issue in the same manner as cold does. There are instances in authors
even of the colour of the hair being changed by excessive fright.
Philip V died suddenly on being told that the Spaniards had been
defeated, and, on opening him, his heart was found ruptured. Timid
people are more liable than others to fall sick. A firmness of mind is
one of the best preservations against contagion. Willis has very well
observed, that they who fear the small-pox the most are generally the
first to be attacked with it. Cheyne assures us that fear is extremely
prejudicial in all epidemical diseases. Dr. Rogers remarks, that fear
constantly increases the ravages of a contagious disease. Rivinus
attributed the propagation of the plague at Leipsic wholly to fear. The
French physicians, who wrote on the plague at Marseilles, went so far
as to deny its being contagious, and ascribed its propagation chiefly
to fear.”

As for the cause of the plague itself, Dr. Fordyce supposes it to be
produced by an infection of a particular kind. That which takes place
in Syria and Egypt, he says, has only been clearly described by Dr.
Russel; and it cannot be gathered from the accounts whether this may
be originally produced without having been propagated as the first
class of infections above mentioned are. “That disease (says he) called
the plague, which ravaged this country (England) on considering the
histories of the disease, seems to have been a _fever_,[83] produced by
infections of the first class which have been enumerated.” Dr. Moore
has given an account of the origin of a plague, which, if it could
be depended upon, would decide the question concerning the origin of
this dreadful distemper without previous infection. This passage is
extracted from the History of the Royal Medical Society for the years
1777 and 1778. “Dr. Mitchell, physician to the hospital at Smyrna,
appears, according to a memoir of which he is the author, sent by M. le
Baron de Tott to the Medical Society to believe in the spontaneity of
the plague (or that it arises of itself without any predisposing cause
in the body) for proof of which he cites the following circumstance:
A solitary shepherd, having no communication with any body, fell sick
while he was tending his flocks; he went into an inhabited part, where
he communicated the plague with which he found that he was attacked.
This circumstance would prove much, if it was certain that the shepherd
had no communication with others; if it were known how long, and with
what precaution, he had been secluded from company: but the proofs of
these are too difficult to be established to allow of any conclusion
to be drawn from the fact. We are obliged therefore to acknowledge [it
to be a doubtful matter] whether it is in fact a country that is the
cradle of the plague; what country this is, supposing that such an one
exists; or, finally, whether it sometimes appears spontaneously, and
whether the first whom it attacks becomes the focus from whence it
emanates.”

  [83] This is expressly denied by Dr. Hodges, who had innumerable
  opportunities of seeing the distemper.

Dr. Fordyce, in treating of the origin of fever, seems inclined to
think that it may arise without any predisposing cause; and after
having enumerated the various causes already mentioned, and fully
considered them, gives it as his opinion, that “there must undoubtedly
be other causes than those which give occasion to the disease, but
which are at present _totally unknown_.” In like manner Dr. Moore,
speaking of the nervous fever, sums up what may be known concerning
the cause of it in the following words. “Upon the whole, we know that
people of delicate, exhausted and sickly constitutions, and those whose
minds are saddened by depressing passions, are greatly predisposed
to this disease, the immediate seeds of which, we also know, may be
generated in places where human effluvia are collected and confined.
And this is the most essential part of our knowledge respecting
the cause of this disease; and even this little is disturbed with
uncertainty: for we sometimes meet with instances of people of _robust
constitutions_, who are seized with the disease in all its malignity,
when they are under no _depressing passion_, when the disease is _not
epidemic_, to whom we cannot trace it from any place where the human
effluvia could be confined in any uncommon degree, or from any person
in the disease, of which perhaps there is no other person ill in the
neighbourhood for several miles round; and, in short, when we cannot
connect it with any of the causes supposed to be the sources of the
distemper. On extraordinary occasions of this kind we have nothing
for it but to suppose that, notwithstanding the apparent vigour of
the patient, his body has been peculiarly predisposed to catch the
infection, and that some contagion, not forcible enough to infect any
other person, has by some means, unobserved, been conveyed to him; or,
if so many suppositions displease, we may suppose at once that there
is in some cases a source of this fever which has not been suspected.
For, although the numerous observations that have been made give us the
strongest reason to think that human effluvia produce this disease,
we have no right to infer that it cannot arise also from some other
source.”

To the same purpose I subjoin the very respectable opinion and
testimony of Dr. Patrick Russel. “In some epidemical distempers, the
sudden alternations of the air have constant and manifest influence; in
others, though the influence of the air must be equally admitted, it
seems not to depend on sensible alteration or succession in the common
properties of the atmosphere, but on some _inexplicable_ combination,
some _occult, new, unknown_ quality. Amongst epidemics of this last
kind must be reckoned the plague.... Should ever that state of the
air, without the concurrence of which the contagion of the pestilence
never spreads, or ceases to act, be discovered, and ascertained by
unequivocal marks, the dread of the plague, universally prevalent,
would be greatly diminished; more effectual means of preservation would
be found out, and the application of them might safely be limited to
certain seasons.

“Experience in Turky, where, generally, no precautions are taken in
the times of pestilence, clearly evinces, that, in a certain state
of the air, a communication with infected places may subsist without
any material consequence. The return of the plague at Aleppo happens
at irregular periods; the intervals are of considerable, but unequal,
length; and in those the commerce with Egypt, Constantinople and
Smyrna remains uninterrupted. In the intervals between 1744 1760, and
from 1762 to 1780, the plague raged several times in the places now
mentioned, without affecting Aleppo; and even in two or three years
subsequent to 1762, though it was at Marash, as well as other places
not far distant, with which Aleppo has continual intercourse, no
instances were discovered of communicated infection: if such happened,
they must have escaped my utmost vigilance; and the daily exercise of
my profession led me to be very much among the natives of all ranks. At
the same time I have reason to suspect that infected families from some
of those places took refuge in Aleppo; and I know, with certainty, that
not only some merchants of that city, who happened to be at Marash when
the plague broke out there, returned to their families in the summer of
1763, but that caravans of various merchandise arrived in the course of
the same summer.

“I consider it therefore as an established fact in the Levant, that
commerce and intercourse with infected towns is sometimes attended
with no bad consequence. The same thing may perhaps be asserted,
without restriction, of all countries; but till the signs indicating
a pestilential constitution be ascertained, no particular year can
be declared exempt from danger. Predictions founded on _planetary
conjunctions_ have been long exploded; and signs derived from the known
properties and alterations of the air, are almost equally fallacious.
The seasons concomitant with plagues in England, as well as elsewhere,
have been very dissimilar; and the same visible concurrence, usually
deemed pestilential, has often, in the revolution of years, been
observed to return, in various countries, without producing the dreaded
consequences. Upon the whole, from all I have been able to collect,
the pestilential constitution seems hitherto to be known only from its
effects; _neither its approach nor its retreat can be predicted and its
nature remains wrapped up in_ MYSTERIOUS DARKNESS.”

Having thus seen, that, of the causes commonly assigned for epidemical
diseases, not one can be accounted certain and determinate, it now
remains to consider one more, and that is

_Contagion._ Though this has been generally accounted the same with
_infection_, yet by some it has been reckoned otherwise; and indeed
there seems to be a necessity for such a distinction; for, though we
should prove, ever so clearly, that a disease once communicated to one
person should from that person be communicated to another, yet the
difficulty is to know from whence the first person had it. This source,
if any such can be found, is what we may with the greatest propriety
distinguish by the name of _contagion_, and is the sense in which it
shall for the future be used in this treatise, the matter communicated
from one person to another being always called _infection_. This
indeed differs from what many celebrated physicians have said upon the
subject; but the distinction certainly must exist. Dr. Cullen speaks
rather indistinctly upon the subject. “We have supposed that _miasmata_
are the cause of intermittents, and _contagions_ the cause of continued
fevers, strictly so named; but we cannot with propriety employ these
general terms. The notion of _contagion_ properly implies a matter
arising from the body under disease, _miasma_, a matter arising from
other substances. But, as the cause of continued fevers may arise
from other substances than the human body, and may in such cases be
called a _miasma_, and, as other miasmata also may produce contagious
disorders, it will be proper to distinguish the cause of fevers by
using the terms _marsh_, or _human_ effluvia, rather than the general
ones _miasma_, or _contagion_.”

From this it is not very easy to determine what the Doctor means when
he speaks of _specific contagion_ as the cause of the plague. Dr.
Russel plainly ascribes it to human effluvia. “The plague (says he) is
a contagious disease; that is, an _emanation from a body diseased_,
passing into one which is sound, produces, in time, the same disease,”
&c. There must, however, undoubtedly have been something originally
distinct from the human body which gave rise at least to the _first_
plague that was in the world; and some plagues recorded in history are
said to have arisen in this way. Thus, Ammianus Marcellinus says that
the plague which broke out in the Roman army in the time of Marcus
Aurelius arose from a pestilential vapour confined in a golden coffer
dedicated to Apollo. Upon opening this, the _contagion_ diffused
itself all around, and the _infection_ spreading from one to another,
produced an almost universal pestilence. Ammianus indeed is the only
historian who relates this; another account of its origin is given,
p. 14, but whether we believe the account of Ammianus or not (which
indeed does not appear probable) it is sufficient to show what were
the received opinions at the time. In like manner every one has heard
of pestilential effluvia breaking out from the earth, from graves,
&c. so that we certainly look upon this doctrine of _contagion_ as
the cause of diseases to have been pretty generally received. We are
also informed by Dr. Mead, from M. Villani, who wrote the history of
those times, that the great plague of 1346 began in China, where,
according to the report of some Genoese sailors, it was occasioned
by a great ball of fire that either burst out of the earth, or fell
down from heaven. This is thought incredible by Dr. Mead, and no doubt
is so, but it shows the general opinion, that the original cause or
_contagion_ which produces a plague is distinct from the _infection_
which is afterwards communicated from one to another. In the French
Encyclopedie, we have this account of the ball of fire, or fiery
vapour, without any comment.

As to the opinion of pestilential vapours arising out of the earth,
though we are assured that people have been suddenly killed by
explosions, probably of the electrical kind, or by lightning issuing
from under their feet, yet we are not furnished with any well
authenticated accounts of a _plague_ having arisen from any such cause.
About 19 years ago a violent fever raged epidemically through a small
district in the north of Scotland, which was said to have originated
in the following manner. Some young men having heard that a certain
place in their neighbourhood had, in the time of a plague been a
burial ground, took into their heads to dig into it. They did so, and
one of them immediately fell sick, but recovered. The father of two
of the young men, exceedingly displeased at the conduct of his sons,
and apprehensive of the consequences, filled up the hole they had dug
in the ground, soon after which he fell sick and died, and the fever
continued to rage in the neighbourhood for some time. The mother of
another of the parties concerned also died, and boils broke out on
various parts of the bodies of the sick. This was the account given in
some of the news-papers of the time, and had the matter been thoroughly
investigated and attested, would have been decisive in favour of
pestilential contagion being capable of taking up its residence in the
earth. As it stands at present, it can only draw our attention to what
may happen in another case, should any similar one occur.[84]

  [84] Though the writer of this Treatise was not at that time on the
  spot where this event took place, yet he has as good evidence as any
  one can have of what has not fallen under his immediate inspection,
  that these graves were opened, that the father of one of the young
  men died; and the mother of another, and one of the young men himself
  was taken ill with the eruption of boils on some parts of his body;
  but whether there was any person previously affected with fever in
  the neighbourhood from whom it might have been derived, or any thing
  which might have strongly predisposed those people to it, is unknown.
  It is indeed no easy matter to discover who was the first person
  affected with an epidemic, as no body chooses to own that either
  they, or any of their relatives were the authors of mischief, however
  involuntary, to the community. M. Chaptal, however, in his Elements
  of Chemistry, has some curious, as well as useful observations on the
  propriety of burying bodies in a sufficient space and at a sufficient
  depth; and on the accidents which may arise from opening vaults
  and burying grounds. An instance of this he gives of the ground of
  a church in Paris being dug up, which emitted a nauseous vapour,
  affecting several people in the neighbourhood.

  From M. Chaptal’s observations it appears, that bodies do not soon
  dissolve in such a manner as to emit no disagreeable or noxious
  effluvia, when buried. M. Becher, he says, “had the courage to make
  observations during the course of a year upon the decomposition of
  a carcase in the open air. The first vapour which rises, he says,
  is subtle and nauseous: some days after, it has a certain sour and
  penetrating smell. After the first weeks the skin becomes covered
  with a down, and appears yellowish; greenish spots are formed in
  various places, which afterwards become livid and black; a thick
  glosey or mouldy substance then covers the greatest part of the
  body: the spots open and emit a sanies.” In such as are buried the
  decomposition is much more slow; our author thinks _four times_ at
  least. According to M. Petit, a body buried at the depth of four feet
  is not decomposed in less than three years, and, at a greater depth
  the decomposition is still more slow. This decomposition is favoured
  by the presence of water, and likewise by some kinds of earth more
  than others. It has been proved by Lemery, Geoffroy, and others, that
  argillaceous earths have very little effect in this way: porous and
  light earths much more: the roots of vegetables also by absorbing
  the putrid effluvia contribute greatly to the final decomposition of
  bodies buried in places exposed to the open air; but in churches and
  other covered places the case is vastly different. “Here, says our
  author, is neither water nor vegetation; and consequently no cause
  which can carry away, dissolve or change the nature of the animal
  fluids: and I cannot but applaud the wisdom of government which has
  prohibited the burying in churches; a practice which was once a
  subject of horror and infection.

  “The decomposition of a body in the bowels of the earth can never
  be dangerous, provided it be buried at a sufficient depth, and that
  the grave be not opened before its complete dissolution. The depth
  of the grave ought to be such that the external air cannot penetrate
  it; that the juices with which the earth is impregnated may not
  be conveyed to its surface; and that the exhalations, vapours, or
  gases, which are developed or formed by decomposition, should not be
  capable of forcing the earth covering which detains them. The nature
  of the earth in which the grave is dug, influences all its effects.
  If the stratum which covers the body be argillaceous, the depth of
  the grave may be less, as this earth difficultly admits a passage
  to gas and vapour; but, in general, it is admitted to be necessary
  that bodies should be buried at the depth of five feet to prevent all
  these unhappy accidents. It is likewise necessary to attend to the
  circumstance, that a grave ought not to be opened before the complete
  decomposition of the body. The term of decomposition is various;
  according to M. Petit of three years in graves of four feet, and
  four years in those of six feet. The pernicious custom which allows
  a single grave to families more or less numerous, ought therefore to
  be suppressed; for, in this case the same grave may be opened before
  the time prescribed. It is likewise necessary, to prohibit burying in
  vaults, or even in coffins.”

With regard to epidemics occasioned by the action of electricity, we
cannot indeed produce any instance; but we have one of a distemper
more dreadful than even the plague itself; and that is of a person
suddenly struck by an electric flash (generated either in his own body,
or in the room where he was) and by this stroke reduced to a most
deplorable condition, which soon ended in death. The account stands
on the authority of Mr. Joseph Battaglia, surgeon at Ponte Bosio, who
transmitted it to Florence, and is as follows.

“Don G. Maria Bertholi, a priest residing at mount Valere in the
district of Livizzano, went to the fair of Filetto, on account of some
business which he had to transact, and after spending the whole day
in going about through the neighbouring country, in order to execute
commissions, in the evening he walked towards Fenille, and stopped at
the house of one of his brothers-in-law, who resided there. No sooner
had he arrived, than he desired to be conducted to his apartment,
where he put a handkerchief between his shoulders and his shirt,
and, when every body retired, he began to repeat his breviary. A few
minutes after, a loud noise was heard in Mr. Bertholi’s chamber; and
his cries having alarmed the family, they hastened to the spot,
where they found him extended on the floor, and surrounded by a faint
flame, which retired to a greater distance in proportion as it was
approached, and at length disappeared entirely. Having conveyed him to
bed, such assistance as seemed necessary was given him. Next morning
I was called, and after examining the patient carefully, I found that
the teguments of the right arm were almost entirely detached from the
flesh, and hanging loose, as well as the skin of the lower part of
it. In the space contained between the shoulders and the thigh, the
teguments were as much injured as those of the right arm. The first
thing, therefore, to be done, was to take away those pieces of skin;
and, perceiving that a mortification was begun in that part of the
right hand which had received the greatest hurt, I scarified it without
loss of time; but notwithstanding this precaution, I found it next day,
as I had suspected the preceding evening, entirely sphacelous. On my
third visit, all the other wounded parts appeared to be in the same
condition. The patient complained of an ardent thirst, and was agitated
with dreadful convulsions. He voided by stool bilious putrid matter,
and was distressed by a continual vomiting, accompanied with a violent
fever and delirium. At length the fourth day after a comatose sleep of
two hours, he expired. During my last visit, while he was sunk in the
lethargic sleep of which I have spoken, I observed with astonishment,
that putrefaction had already made so great progress, that his body
exhaled an insupportable smell. I saw the worms which issued from it
crawling on the bed, and the nails of his fingers drop of themselves;
so that I thought it needless to attempt any thing farther, while
he was in this deplorable condition. Having taken care to get every
possible information from the patient himself, respecting what had
happened to him, he told me, that he had felt a stroke, as if somebody
had given him a blow over the right arm, with a large club, and that at
the same time, he had seen a spark of fire attach itself to his shirt,
which in a moment was reduced to ashes, though the fire did not in the
least injure the wrist-bands. The handkerchief which he had placed upon
his shoulders, between his shirt and his skin, was perfectly entire,
without the least appearance of burning, his drawers were untouched,
but his night-cap was destroyed, though a single hair of his head was
not hurt. That this flame under the form of elementary fire, burnt the
skin, reduced the shirt to ashes, and entirely consumed the night-cap,
without in the least touching the hair, is a fact which I affirm to be
true: besides, every symptom that appeared on the body of the deceased,
announced severe burning. The night was calm, and the circumambient air
very pure: no bituminous smell could be perceived in the chamber, nor
was there the least trace of fire or of smoke. A lamp, however, which
had been full of oil, was found dry, and the wick almost in ashes. We
cannot reasonably suppose this fatal accident to have been occasioned
by any external cause; and I have no doubt that if Maffei were still
alive he would take advantage of it to support an opinion which he
entertained, that lightning is sometimes kindled in the human body and
destroys it.”

Another account, to the same purpose, is given in Mr. Battaglia’s
paper. “On the 21st of April, 1781, the first battalion of the brigade
of Savoy set out from Tortona, in order to go to Arti, when the weather
was excessively hot. On the 22d, having made rather a forced march, the
soldiers suffered a great deal from the ardour of the sun, so that, at
the village of Serre, where they halted, one of them, named Bocquet, a
man of twenty-five years of age, whose skin being very hard and thick
had not perspired, sent forth a loud cry, which seemed to announce
some extraordinary commotion, and instantly fell down. Mr. Bianet,
surgeon major to the regiment, found the patient in convulsions.
When he was carried to the hospital the upper part of his body, to
the thighs, appeared to be withered and black, and in a gangrenous
state. Mr. Bianet employed scarifications, but without effect; it was
impossible to make him swallow any thing; and it was found necessary to
abandon him to his dismal fate. His body soon exhaled a putrid smell,
and he died at the end of five hours. That his disorder might not be
communicated to others, he was interred together with his clothes. Upon
inquiry, after his death, it was found that this man was addicted to
the constant use of spiritous liquors, and that he had even drank of
them to excess upon the march.”

Other instances there are, still more terrible, of people actually
taking fire and being consumed to ashes by some internal cause; but, as
nobody was present either at the beginning or during the continuance of
these extraordinary inflammations, nothing certain can be said about
them. That such things, however, have happened, is certain, of which
one of the most remarkable instances is that of Signora Corn. Zangari,
an Italian lady. She retired to her chamber in the evening somewhat
indisposed, and in the morning was found in the middle of the room
reduced to ashes, all except her face, legs, skull and three fingers.
The stockings and shoes she had on were not burnt in the least. The
ashes were light, and on pressing them between the fingers vanished,
leaving behind a gross, stinking moisture, with which the floor was
smeared; the walls and furniture of the room being covered with a moist
cineritious soot, which had not only stained the linen in the chests,
but had penetrated into the closet, as well as into the room overhead,
the walls of which were moistened with the same viscous humour. This
lady had been accustomed to use a bath of camphorated spirit of wine
when indisposed.

Dr. Zimmerman, from the 64th volume of the Philosophical Transactions,
relates the case of a poor woman who perished in this miserable manner
at Coventry in England in the year 1772. “She fell out of bed, and was
found next morning burnt to death, though the fire in the grate had
been small, and the furniture in the room had suffered but little.
Except one thigh and leg, there were not the least remains of any skin,
vessels or viscera; and the greater part of the bones were completely
calcined, and covered with a whitish efflorescence.”

On these unfortunate people it has been observed that they were
generally intemperate in the use of spiritous liquors. Of the poor
woman at Coventry, whose case has been just now related, it is said,
that she had been in the practice of drinking from half a pint to a
quart of rum every day, and this she continued, notwithstanding her
being affected with jaundice and other complaints. Mr. Wilmer, who
communicated this case to the Royal Society, concludes it with these
words: “That her solids and fluids were rendered inflammable by the
immense quantity of spiritous liquors she had drank, and when she was
set fire to she was probably soon reduced to ashes.”

On other cases of a similar nature it has been remarked, that the
miserable sufferers were “for the most part advanced in years,
remarkably fat, and had been much addicted to the use of spiritous
liquors, either in their drink, or applied in friction to the body;
whence it has been concluded that these people perished by their whole
substance spontaneously taking fire, the principal seat of which had
been the entrails, or the epigastric viscera; and that the exciting
cause was naturally found in the phlogiston of the humours, called
forth by that of the spiritous liquors combined with them.”[85] But
solutions of this kind cannot by any means be admitted. We have not
the smallest reason to think that either the solid or fluid parts of
the bodies of hard drinkers are more inflammable than those of other
people; neither is it credible that any person could live with his body
in such a state. Besides, the most inflammable bodies will not begin to
burn unless fire actually be applied to them, while others much less
inflammable to appearance, will yet take fire spontaneously. Thus, even
spiritous liquors themselves, though they flame violently when thrown
into a fire, or when a burning body is applied to them, yet there
is not an instance of such liquors taking fire of themselves; nay,
they cannot even be set on fire by pouring them upon a red-hot iron,
while, on the other hand, heaps of wet vegetables, which we should
think scarce at all inflammable, do yet very frequently take fire
spontaneously. The author lately quoted, however, justly observes that
M. Bartholi, the unfortunate priest above mentioned was plainly struck
first by electricity from without, a spark of fire attaching itself to
his shirt, and a faint flame surrounding his body; so that the fire did
not seem to have been generated in his body, but in the atmosphere.
There are instances of people being surrounded with these luminous
appearances without being hurt; particularly of a woman at Milan, whose
bed was surrounded with a light of this kind. Mr. Loammi Baldwin, of
this country, was also surrounded by an electric light, while raising
a kite in the time of a thunder storm, and Dr. Priestley makes mention
of a gentleman, who, after having worked an electric machine for a
long time in a small room, perceived, on leaving it, a luminous vapour
following him. But the instances most to our present purpose are some
recorded in the Philosophical Transactions, of luminous vapours coming
from the sea, attaching themselves to corn-stacks, and setting fire
to them. One of this kind is particularly mentioned in Lowthorp’s
Abridgement of the Transactions, as having taken place in Ireland,
coming repeatedly from the sea, and setting fire to corn and hay, so
that the people were greatly alarmed. At last they found that it might
be driven off by making a great noise, and that it would avoid any
sharp-pointed iron instrument. Had such a vapour attached itself to a
human body, it is possible that it might have set fire to it as well as
to the stack of corn or hay. Whether these accounts render the story of
the Genoese sailors concerning the ball of fire occasioning the plague
of 1346 more credible, we leave the reader to judge. They certainly
show, however, that the electric fluid will sometimes interfere with
the human body in a very terrible manner, producing, where it does not
kill instantaneously, symptoms equal to those of the very worst plague,
as in the case of the priest and soldier above mentioned.

  [85] American Museum vol. xi, p. 148.

Another hypothesis concerning the origin of pestilential diseases is
that of swarms of little animals invisibly existing in the atmosphere;
which, being taken into the body by the breath, are supposed to corrupt
or otherwise vitiate the blood and other parts of the body, as we
see in the plague and other epidemic disorders. This hypothesis, so
generally exploded, and so apparently improbable, seems to receive
some support from a discovery of an insect made by Mr. Henry Baker, F.
R. S. and published in his work entitled “The Microscope made Easy.”
He called it the insect with net-like arms. “It lives (says he) only
in cascades, where the water runs very swift. Some of them being kept
in a vial of water, most died in two days, and the rest, having spun
themselves transparent cases, which were fastened either to the sides
of the glass, or to pieces of grass put into it, seemed to be changed
into a kind of chrysalis; but before they assumed this form, they
altered their shape (in a manner he represents by a figure.) None of
them lived above three days; and, though fresh water was given them
two or three times a day, yet in a few hours it would stink to a degree
scarce conceivable, and that too at several yards distance, though, in
proportion to the water, all the included insects were not more than
as one to _one million, an hundred and fifty thousand_. This makes it
probable that it is necessary for them to live in a rapid stream, lest
they should be poisoned by the effluvia issuing from their own bodies,
as no doubt they were in the vial.”

From this account it is not difficult to conceive that animals, though
exceedingly small, may yet emit such poisonous effluvia as will
destroy much larger ones in their neighbourhood. It will by no means
be incredible that, had one or two such offensive animals been thrown
into a jar containing gold-fishes,[86] the whole of these beautiful
inhabitants would have perished at once. Let us suppose such a thing
to have actually happened; that a malicious person had put them in
over night, and in the morning the proprietor of the fishes finds
them all dead, and the water offensive to the last degree. He sends
for a neighbouring philosopher, who, happening to be ignorant of the
existence of such animals, endeavours to account for the phenomenon
upon some of the received principles of philosophy. How much theory
would here be wasted, and what endless disputes might ensue without
even a _possibility_ of arriving at the truth! Just so it is with
epidemic diseases. The cause is invisible, and, until it becomes
discoverable by our senses, it can never be known; for, as has already
been observed, a cause never can be known merely by its effects, unless
we have seen it, or somebody who has seen it gives us information. And
this will certainly be found to hold good in every instance, even from
the Supreme Cause himself to the diminutive insect just mentioned.

  [86] The gold-fish is a small species of carp, brought originally
  from China. They are adorned with the most beautiful and resplendent
  colours, and are frequently kept in jars for pleasure. They subsist
  entirely on the water, without any other food. This is by Dr.
  Fordyce said to be the case with all fishes, provided the water be
  impregnated with oxygen.

Lastly, I shall consider another _possible_ source of epidemics, which
has been hinted at by others. Allowing that infectious matter proceeds
from the body of a diseased person, as much must issue from a single
patient as is sufficient to bring the disease upon thousands, and
with regard to the small-pox and some other distempers we certainly
know that it is so. This infection is dissipated in the atmosphere,
and intimately combined with it, so that it becomes imperceptible and
harmless; but we have no reason to suppose that it is annihilated, or
cannot be re-produced in its pristine state. Water, though perfectly
dissolved, and to appearance deprived of existence in the air, may
yet be precipitated from it, and pour down upon us in deluges. What
happens in one case may happen in another. The infectious matter,
dissolved in the air, may by some natural cause be precipitated from
it, overshadowing whole regions, and, if it be not powerful enough to
produce the epidemic of itself, may certainly _predispose_ to it in
such a degree, that the slightest additional cause will bring it on.

Something indeed of this kind would seem really to be the case,
otherwise we cannot well conceive why there should be such a
distinction of diseases. Thus the infection of the small-pox is the
same all over the world. The variolous matter will never produce the
measles in any country, nor will the typhus produce a pleurisy. The
plague manifests itself to be the same distemper in all its various
degrees of malignity, though even this dreadful disease is sometimes
so mild that it does not confine the patient to his bed. There must
therefore be some certain constitution in the nature of the cause
which produces such and such diseases, as certainly as in the seed
of particular vegetables, which gives to each its proper appearance
and shape. The cause of the disease so modified we may call, with Dr.
Cullen, its _specific contagion_.

Having thus treated so largely upon contagion of different kinds, it
now remains to consider the objections that have been made to the
doctrine altogether. It is indeed surprising that in so great a length
of time, after the world hath so often and so dreadfully suffered from
the violence of plagues, the simple fact, whether it be infectious
or not, should not have been determined: nay, that it should still be
questioned by physicians of no mean reputation whether such a thing as
contagion or infection _can possibly exist_. Dr. Mosely in his treatise
on tropical diseases treats the whole doctrine of contagion with the
utmost contempt; calling it “a field for speculation, which has long
amused the pedantry of the schools, and should never be entered into by
practical writers.” Notwithstanding this, however, he doth enter into
it, and with such bad success, that in the very first paragraph he is
obliged to derive the cause of diseases from the stars! “There are some
diseases we know, (says he) which follow the changes of the atmosphere;
but there are others which make their revolutions, and visit the earth,
at uncertain periods; for which we can trace no cause, depending on
combinations, in which, perhaps, the _influence of the planets_ may
have some share.” Here we have a still wider field for speculation than
even _the schools_ have given us; for the Doctor ought to remember that
the influence of a _planet_, producing a disease, is as truly contagion
as the effluvia of a _dunghill_; and if we have a wide field to
traverse when tracing it through the earth, we have one infinitely more
extensive in pursuing it through the heavens. But we may be assured
that planetary influence _does not_ produce diseases; for, if it did,
they would in all times of pestilence overspread the face of the earth,
as the influence of the planets, if they have any, certainly does.

The arguments used by this author against _terrestrial_ contagion are,

1. “It has often happened that hundreds of men in a camp have been
seized with the dysentery, almost at the same time, after one shower of
rain, &c. People under similar circumstances must be subject to similar
diseases: and yet it often happens that dysentery begins with a few
people, and spreads itself by degrees until a multitude are affected.”

This argument rather militates against himself; for, if dysentery
or any other disease was occasioned by an _evident_ general cause
operating upon persons in similar circumstances, all of them ought to
be taken ill at once; but Dr. Mosely owns that they frequently are
not. There must, of consequence, be something _less evident_ which
determines the disease to particular persons, while the general cause
operates equally upon all. This less evident cause we call _contagion_.

2. “It is incredible that the smelling a little human blood, that
had stood some months in a phial, gave the man a dysentery mentioned
by Pringle; or that the person Forestus speaks of got the plague
by only putting his hand into an old trunk; or that the shaking an
old feather-bed, which had lain by seven years, raised a plague at
_Wratislau_, which destroyed five thousand persons in twelve weeks, as
related by Alexander Benedictus, &c.--Such things _may be true_, but,
when probability is shaken, reason always inclines to skepticism.”

Here our author most evidently contradicts himself; for in the
beginning of the paragraph he tells us that the things related are
_incredible_, and in the end of it, that they _may be true_. The
argument, if it may be so called, is mere assertion. It is _incredible_
that the smell of putrid human blood in a vial should produce the
dysentery. Why should this be more incredible than that smelling to
a charged vial should ensure an electric shock to the person who did
so? This is entirely a question respecting a matter of fact, not
of speculation. The same is the case with the rest. It is not more
incredible that, if the infection of the plague was in a trunk, a man
should get the plague by putting his hand in it, than that he should
be burnt if he put his hand into a trunk full of hot ashes. Before the
Doctor decided in such a positive manner, he ought to have proved that
no infection could be contained in a trunk; but this, though the very
point in question, he takes for granted, first telling us that the
contrary is incredible, and then that it may be true!

3. “We observe in camps and hospitals, that those people _whose dirty
employments_ subject them in a particular manner to a _depravation of
their habits_, seldom escape the present epidemic; and this gives rise
to the vulgar expression, and very incorrect notion, of _catching_
the disease. And we observe that others from the slightest deviation
from regularity lose the power by which the body resists diseases, and
they are also attacked. But these attacks are not to be attributed to
infection: for those people who keep the vital and animal powers in
uniform confederacy, by temperance and calmness of mind (for fear, by
lowering the vital energy, subjects the body to disease) nourishing
diet, proper clothing and cleanliness, and keeping a free and regular
passage for all excretions, are proof against the assaults of foul and
pestilential air. Such people seldom suffer even by the plague itself:
while all around them perish.”

The first sentence of the above paragraph is so obscurely worded,
that it is difficult to know the author’s meaning. I know not of any
lawful employment so _dirty_ that it necessarily subjects the person
who practises it to a _depravation of habit_. The next ascribes every
thing to intemperance and fear; from which, it seems, we are to infer
that none but drunkards, cowards, and dirty, naked ragamuffins, are
ever seized with epidemic diseases. But of this we are able to bring a
direct disproof. I suppose Dr. Mosely will not say that the celebrated
Prince Eugene of Savoy was either a coward or a drunkard; that he had
a _dirty employment_, wanted proper food or clothes, or was deficient
in personal cleanliness; yet, when in the marshy parts of Hungary, he
was in danger of death from an epidemic dysentery, notwithstanding
that he was so careful in respect of diet, that he had pure water
brought him every day, probably from a considerable distance. How
came he to be affected by the distemper under such circumstances,
while Count Boneval, though as an inferior officer he probably enjoyed
fewer advantages, remained free from it, taking only a small quantity
of Peruvian bark daily? It is uncertain whether the bark did really
preserve him or not; but the case of Prince Eugene plainly shows that
sobriety, temperance, valour and cleanliness are not sufficient to
ward off an epidemic disease, if people come in the way of infection.

4. “It should follow, if contagion were supported by infected bodies,
that no person should ever escape infection (as at Oxford assizes in
1577[87]) who was within the sphere of its action; and that those
who were entirely secluded from it, and free from all contiguity to
infected people, or substances, as the collegers were in the town of
Cambridge, when the plague was last in England, should be exempt from
it.

  [87] Sir John Pringle, from Stowe’s Chronicle, gives the following
  account of these assizes. “On the 4th, 5th and 6th days of July were
  the assizes held at Oxon, where was arraigned and condemned Rowland
  Jenkins, _for a seditious tongue_; at which time there arose amidst
  the people such a damp, that almost all were smothered. Very few
  escaped that were not taken. Here died in Oxon three hundred persons;
  and sickened there, but died in other places, two hundred and odd.

  “The sessions at the Old Bailey in Westminster, in 1650, proved also
  fatal to many; of which Sir John also gives an account. ‘I have been
  informed (says he) that, at those Sessions, about a hundred were
  tried, who were all kept in close places as long as the court sat;
  and that each room was but 14 feet by 11, and seven feet high. The
  bail-dock is also a small room taken off one of the corners of the
  court, and left open at the top: in this, during the trials, are put
  some of the malefactors who have been under the closest confinement.
  The hall in the Old Bailey is a room of only 30 feet square. Now
  whether the air was most tainted from the bar by some prisoners then
  ill of the jail distemper, or by the general uncleanliness of such
  persons, is uncertain; but it is probable that both causes concurred.
  And we may easily conceive how much it might have been vitiated by
  the foul steams of the bail-dock, and of the two rooms opening into
  the court in which the prisoners were the whole day crowded together
  till they were brought out to be tried. It appeared afterwards, that
  these places had not been cleaned for some years. The poisonous
  quality of the air was aggravated by the heat and closeness of the
  court, and by the perspirable matter of a number of people of all
  sorts, penned up for the most part of the day, without breathing
  the free air, or receiving any refreshment. The bench consisted of
  six persons, whereof four died, together with two or three of the
  counsel, one of the under sheriffs, several of the Middlesex jury,
  and others present to the amount of above forty; without making
  allowance for those of a lower rank, whose death may not have been
  heard of; and without including any that did not sicken within a
  fortnight after the sessions.’”

    (Pringle’s Observations p. 329 & seq.)

“But, in opposition to this, _Rhazes_ lived 120 years, an often
practised in plagues. _Hodges_ remained in town, and attended the sick,
during the great plague in 1665. _Kaye_ was in the midst of practice in
the sweating sickness in 1551, without any inconveniency. _Procopius_
informs us, that during a terrible plague at Constantinople, in 543,
which almost destroyed the whole city, no physician nor other person
got the plague by attending, dressing or touching the sick. Yet most
of the Capuchins, the Jesuits, the Recollets, the Observantines,
the Barefooted Carmelites, the Reformed Augustines, all the Grand
Carmelites, the Grand Trinitarians, the Reformed Trinitarians, the
Monks of Loretto, of Mercy, the Dominicans, and Grand Augustines, who
kept themselves secluded in their several convents, and took every
precaution to avoid the plague, while it raged at Marseilles, perished
by it.

“There are no epidemical nor contagious diseases that attack every
person who breathes the same air, or that is in contact with the
infection, else whole regions would be depopulated. The habit must
be graduated, or adapted, for the reception of a disease. In some
constitutions of body the access is easy, in some difficult, in others
impossible. _But where the revelation of this mystery is to be found,
none can tell._”

In this, which our author seems to have designed as his _grand
argument_, it is plain that the deficiency is as great as in any of
the rest. If we suppose the plague, or any other epidemic disease, to
arise from some general cause, let that cause be _contagion_ or any
thing else, it ought to operate upon all who come within its sphere
of action, as Dr. Mosely observes of _infection_. If experience
shows that it does not, the argument will hold equally against a
constitution of the atmosphere, putrid effluvia, heat, cold, or any
thing else; and in fact the Doctor fairly gives up the point at last,
by resolving the whole into an _unrevealed_ mystery. With regard to
what he says about the plague at Marseilles getting into the convents,
of which he presents us with such a catalogue, it is impossible to
know what precautions were used, and we are assured that in Turky it
is thought necessary for the Europeans not only to guard against a
communication with their own species, but some of the brute creation
also. Cats particularly are dreaded so much, that a general massacre
of them commences among those who use precautions, the favourites
of that species must be sent to a distance, and M. Volney mentions
two merchants who had shut up their houses, and yet had the plague
imported by a cat. In short, considering that infection is supposed to
be altogether invisible and imperceptible, it is impossible to say how
it may be conveyed, or to what extent it may occasionally act when once
brought into a country. Dr. Fordyce is of opinion that the distance at
which infection may act depends on the disposition of the air at the
time; and he observes, that a difference in this respect is observable
in the odoriferous effluvia of vegetables. “If the air be loaded with
moisture, they reach to a much greater distance. Vapour arising from
a field of beans, for instance, or a putrid ditch, is sensible to the
nostrils at a greater distance if the air is moist.” He observes indeed
that this has never been verified with regard to infection; but as it
is evidently the case with putrid effluvia, which very often accompany
infection, we may reasonably conclude that it is the case with the
latter also.

Let us next take a view of what is advanced by the authors of The
Science of Life upon this subject. Mr. McLean, who puts his name to
this part, informs us of his conviction “that no general disease, which
affects a person more than once during life, can ever be communicated
by contagion;” and he defines contagion “a specific matter, generated
in a person affected with disease, and capable of communicating that
particular disease, with or without contact, to another.” It would
here be no improper question, by what means he comes to know that a
contagious disease can affect a person only _once_. But even this
question is unnecessary. Dr. Guthrie gives an account of a gentleman
who had the courage to inoculate himself for the plague, in consequence
of which he had the disease with the concomitant symptoms of buboes,
&c. Here then we see the plague communicated by “a specific matter
generated in a person affected” with the same disease, i. e. by
_contagion_, according to Mr. McLean’s own definition. The dispute
therefore might stop, as this fact seems to be decisive on the subject;
but as he has at great length insisted upon the argument last quoted
from Dr. Mosely, it seems necessary to follow him a little farther.

“If a person (says our author) be affected with any disease, it will
necessarily be communicated to every other person who comes within the
infectious distance, and _is not at the same time labouring under some
disease higher in degree_.” This proceeds upon a supposition that his
theory is absolutely perfect and infallible; which, however plain it
may appear to himself, will not probably be admitted by others without
some proof. Indeed he himself afterwards adduces some facts which
decisively overthrow it. “A child (says he) here and there is exempted
from small-pox, even though exposed to its contagion.” How comes this
to pass? The disease, we are told, is contagious, the child is exposed
to the contagion, and yet is not affected. In _all_ such cases it would
be ridiculous to suppose the subjects labouring under a disease higher
in degree than the contagion could produce. In numbers of instances of
this kind the children were evidently in good health, and yet would
perhaps be seized at an after period when no more exposed to contagion
than they had been at first.

“Small-pox, measles, and other general diseases, which occur only once
during life, never disappear, until _the whole_ of those who have been
within the infectious distance, and were not at the time labouring
under some disease higher in degree, have received the infection. As
these diseases are _very mild_, children sometimes resist the power of
contagion from the superior force of some other diseases, although they
may be so slight as to escape _common_ observation.”

In this paragraph we have the favourite maxim of our author repeated,
_twice_ indeed, without a single fact to support it. Instead of this
we find hypothesis heaped upon hypothesis, as the giants are said to
have heaped mountains upon one another in order to get up to heaven.
He first supposes that the infection of the small-pox seizes on _the
whole_ of those on whom it falls. The exceptions to this maxim he
explains by another _supposition_, viz. that the contagion of the
small-pox is counteracted by another disease. The second hypothesis
is supported by a third, and that a very extraordinary one, that
the small-pox (a disease which has destroyed innumerable multitudes)
is _very mild_; and this third by a fourth, that the diseases which
counteracted the contagion were so slight as to escape _common_
observation. It was incumbent on Mr. McLean to have pointed out some
of those diseases, and to have informed us how they came to counteract
this contagion. But it is needless to argue with one who writes
so extravagantly. Far from the mode of reasoning followed by Dr.
Fordyce, who decided from the majority of facts, our author determines
every thing by his own preconceived opinions. “That the power which
occasioned disease at the Oxford assizes (says he) was not contagious
matter, is proved by its producing diarrhœa in some, while it produced
fevers in others.” But, if it was not contagious matter, what kind of
matter was it? Or how comes our author to know that those who were
affected by the diarrhœa were not likewise affected by fever? How many
fevers are attended by diarrhœa, or how many cease when diarrhœa comes
on! It would have been equally conclusive to say that the matter was
not contagious, because some died and some recovered.

I shall only take notice of one assertion more, it being both tedious
and unnecessary to follow him through the whole. “From _every_ record
of epidemic and pestilential diseases, it would appear, that they have
their stated periods of recurrence; that these periods are such months
as are most remarkable for vicissitudes of the atmosphere; that they
become general only in those years in which these vicissitudes are
extreme; that they do not occur in seasons when the heats or colds,
however intense, are equable; nor in years when the state of the
atmosphere is tempered throughout; and that they uniformly cease with
the establishment of an equable state of the atmosphere, whether the
weather be cold or hot.... In Aleppo, according to Dr. Russel, the
Europeans regularly shut themselves up in their houses _every year_,
at some period between April and July; and the rich natives begin to
adopt the same plan, &c.... From this fact it appears, that the plague
occurs at Aleppo, in a state more or less mild, almost annually, and
_that it commences and ceases at certain known periods_. But it has
been remarked that, in its most severe state, this disease recurs only
at periods of ten years, or _thereabouts_: a regularity which cannot,
upon any known principle, be attributed to a power of such casual
application as contagious matter.”

In the beginning of this paragraph our author makes a bold appeal to
_every_ record of epidemic and pestilential disorders; but here we
may ask, Has he consulted _every_ record of these disorders? That he
has not, we may readily believe; but even those which are hinted at
seem either to have been very inaccurately consulted, or wilfully
misrepresented. To evince this I subjoin the following abstract of
what Dr. Alexander Russel says of the plague in general, with the
annotations of his brother, Dr. Patrick, taken from Russel’s Natural
History of Aleppo.

The inhabitants of Aleppo suppose that the plague visits them once in
ten years, and that it is always imported; and the most severe plagues
are thought by some to come from Damascus, while others contend that
they come from the northward. Dr. Alexander Russel thinks this popular
opinion of the return of the plague not altogether unfounded; and he
thinks it also probable that it never invades Aleppo without having
previously attacked either Damascus or Khillis, Aintab, Marash or Uufa.
He thinks that its appearance always is in one of the maritime towns of
Syria; if in Sidon, Byroot or Tripoli, Damascus is commonly the channel
by which it reaches Aleppo; but, if it shows itself first at Scanderoon
or Byass, its approach is by the way of Khillis or Aintab.

On this Dr. Patrick Russel observes, that the account of Aleppo being
visited only once in ten or twelve years is confirmed by a letter from
an English gentleman, in 1719, who had resided there for 30 years. The
dates of the plagues which Dr. Patrick had procured were, 1719, 1729
and 1733. Another began in 1742, and terminated in 1744; from which
time there was no return till 1757 or 1758, when it continued at Aleppo
till 1762, and did not entirely quit the country till 1764. The plague
of 1719 was said to come from the northward, but this appeared to want
confirmation; but all accounts agree that it raged at Tripoli, Sidon,
&c. two months before it appeared in Aleppo. Egypt was ravaged by the
plague in 1728, as was also Byass and the neighbouring parts in the
same summer; and next year it appeared at Aleppo. In 1732 it raged at
Sidon, Tripoli and Damascus; next year it seized Aleppo.

Dr. Alexander goes on to inform us, that the disease never spreads much
in winter. It advances with the spring, comes to its height in June,
declines in July, and terminates in August. “None (he says) are ever
seized with in September and October, not even in the plague of 1742,
which returned three years successively;” but Dr. Patrick says that
this was not confirmed by his experience in 1760, though he owns that
the distemper declines remarkably at that period; and the natives are
greatly inclined to have it believed that the distemper has totally
ceased, and to deceive the Europeans in this respect. The times at
which the Europeans shut up and come out of their confinement show
only the increase or decrease of the disease, but not its beginning or
ending. The plague of 1719 made terrible havoc. Europeans then shut
up about the middle of March, and kept confined till the middle of
July. In 1729 they did not shut up till the middle of May, and were
not confined above a month, the number of sick being small. In 1733
they were confined from the middle of March to the middle of July,
but the distemper was less violent than in 1719. In 1742 the time of
confinement much as in 1729. In 1743 shut up April 11, and opened the
middle of July. The plague violent, but less so than in 1733. In 1744
few shut up, the number of sick being inconsiderable. In 1760 they shut
up on the 30th of June, and continued about a month. In 1761 shut up
May 28, rode out Aug. 1, and opened completely the 10th of that month.
In 1762 they were confined from the last week in May to the first of
August. From 1762 to 1787, a larger period than usual, the city was
free from the plague. In 1787 it broke out among the Jews in the month
of April, increased in May, raged violently in June, and terminated in
July.

From these accounts it appears, as Dr. Alexander Russel informs us,
that the plague of one year differs remarkably from that of another;
but he says, that, at Aleppo, it is never attended with such scenes of
horror as have been known in European countries; for which Dr. Patrick
assigns the following reasons: 1. The markets are constantly supplied
with provisions. 2. The dread of the contagion is much less. 3. The
sick are less liable to be deserted by their attendants (but this,
according to his own observation, is not always the case) and 4. The
regular, speedy interment of the dead prevents a spectacle far from
uncommon in the European plagues, and which of all others is the most
shocking to humanity.

“Extreme heat (says Dr. Alexander) seems to check the progress of the
distemper. July is a hotter month than June, and the season wherein the
plague ceases at Aleppo is that in which the heats are most excessive.”
His experience did not confirm a popular opinion at Aleppo, and which
has likewise been adopted by many medical writers, that the moon has
any influence on the distemper. To have had the distemper once does
not secure a person against future attacks. Numbers of people who were
alive when he left Aleppo had it twice or oftener; and he had instances
of some being infected thrice in one season. Dr. Patrick Russel has
observations to the same purpose.

From this it appears, that the popular opinion at Aleppo, which Mr.
McLean wishes to establish as a certainty, is by no means so well
founded that we can build any theory upon it. The misfortune is, that,
wherever a theory is built upon any thing said to be constant and
invariable, a single failure overturns the whole. Now, in the dates
of plagues above mentioned, the variations are so great that it is
impossible to draw any certain conclusion from them. In the first
three instances of 1719, 1729 and 1733 there is indeed a coincidence of
the first two, but the last falls short by no less than _six_ years.
What then does Mr. McLean mean by his “ten years, or _thereabouts_?”
Can _thereabouts_ imply a difference of more than half? The English
gentleman’s testimony who resided 30 years in that country could extend
no further than to three plagues, and even these are not mentioned. The
fourth instance in 1742 is deficient in one year; the fifth in 1757 or
1758 exceeds by three or four years, and the sixth from 1762 to 1787 by
no less than fifteen years.

An anonymous writer in a Scots periodical publication entitled “The
Bee,” has partly adopted the above opinion, but adds others for which
he has not thought proper to adduce any authority. “It visits _most
parts of Asia_ once in ten or twelve years, and carries off an eighth
or tenth of the inhabitants. There have been plagues which have carried
off one fourth of the inhabitants. The farther east you go, the less
frequent it is--every 20th, 40th, and, even at Bassorah, every 90th
year; but then this scourge is most dreadful. The last plague at
Bassorah, which had not visited the city for 96 years, carried of
more than nine tenths of the inhabitants.”[88] It is astonishing that
people will write in such a manner as to subject themselves to endless
criticism on account of their inconsistency. The plague, this writer
says, visits _most parts_ of Asia once every ten or twelve years, and
yet it goes no farther east than Bassorah; a space scarce equivalent to
the twentieth part of Asia! Even in this small space, it varies from
ten or twelve, to twenty, forty, or even ninety years; and, to complete
the whole, instead of giving any instance of the periodical return
of the plague at an interval of _ninety_ years, we have one of its
disappearance for _ninety-six_ years!

  [88] Bee, vol. xviii, p. 282.

From all this it is evident, that no dependence can be placed on such
vague accounts with regard to the periodical returns of the plague.
Even the time of shutting up the houses in Aleppo is not accurately
related, for, from the above abstract it is plain, that they are
sometimes shut up in March; while Mr. McLean would have us to believe
that it is always between April and July. It is needless to wade
through a jumble of unsupported assertions, which, being backed by no
evidence, fall to the ground of themselves. “I will _venture to assert_
(says he) that no person in perfect health ever was or _can be_ exposed
to the power of contagion, without receiving the specific disease which
that contagion produces; excepting in small-pox, measles, &c. when
the person has previously had the disease.”--How comes he to know all
this? Or, though our author ventures to assert, must we of necessity
_venture to believe_? When he ascribes the origin of epidemics, and
the plague itself, to the vicissitudes of the atmosphere, not a single
fact is adduced in support of his hypothesis. One very strange proof
indeed he brings from Dr. Rush, viz. that the latter had been informed
by a gentleman who resided in tropical countries, that, in the month
of July, several weeks before the yellow fever became general, he had
observed a peculiar and universal sallowness of complexion in the
countenances of the people of Philadelphia, such as he had seen in
those of the more southern countries before the appearance of bilious
fevers in them. Surely it is a very strange mode of argument to tell
us of the colour of people’s countenances instead of the states or
vicissitudes of the atmosphere, which we are made to believe were the
causes of that change. Another quotation is made from the same author
in which a warm, dry, stagnating air is _conjectured_ to have been
the cause of _diseases_; but he does not even quote Dr. Rush saying
that it was the cause of yellow fever, much less of all epidemic
diseases. Besides, to say that any thing is occasioned by a _state_, or
_vicissitude_ of the atmosphere, is such a vague mode of expression,
that it must either mean nothing, or be contradictory to itself. A
_state_ of the atmosphere we must suppose to mean that it continues for
some time either to be wet or dry; a _vicissitude_, when it changes
from one to the other. If an epidemic then is produced by a _state_,
it cannot also be produced by a _vicissitude_, of the atmosphere: or,
if some epidemics are produced by states, and others by vicissitudes,
we ought to be informed which produce one kind, and which another. But
throughout the whole of this dissertation we have neither distinctness
nor regularity, nor indeed any thing but assertion, supported only by
an imaginary theory.

Dismissing at length therefore these conjectural theories, let us
endeavour to deduce from certain and undoubted facts the connexion
between the state of the body, and the operations upon it of other
causes, invisible indeed to our eyes, but discoverable by our rational
faculties, and in some measure capable of being made the objects of our
senses also.

1. From the account given of the structure of the human body, it
undeniably follows, and has already been observed, that all parts of
it are so connected together, that none can suffer any very grievous
injury without affecting all the rest.

2. The life of man depends immediately on the air. From this element
the _blood_ receives heat and a vital spirit diffusing itself from the
blood along the nerves, and thence expended in the operations of life
and sensation.

3. From undoubted experiments[89] it appears, that this vital spirit
possesses in a great degree the properties of electricity, insomuch
that many suppose them to be the same. This is indeed denied by the
celebrated anatomist, Dr. Monro, but he allows that the nervous fluid
is similar to electricity, and it is certain that the electrical fluid
can affect it in such a manner that we may reasonably believe them to
be the same.

  [89] Those of Galvani and others on _animal electricity_.

4. The air acts upon the blood by the _latent_ heat it contains. The
air itself is composed of something volatilised by heat. In some cases
this is evidently a terrestrial substance, as in that of inflammable
air, or hydrogen, which is formed of charcoal volatilised by heat,
with the addition of a little water. In the case of oxygen, or
dephlogisticated air, the combination seems to be the matter of heat
(which I shall hereafter distinguish by the name of the _ethereal
fluid_) with water deprived of its carbonic principle. This coincides
with the opinion of Dr. Priestley, who says that the basis of
dephlogisticated air seems to be _dephlogisticated water_. But, let
the basis be what it will, the ethereal fluid which volatilises it is
the _agent_; the basis is entirely _passive_, and only modifies or
restrains the action of the other fluid, so that it does not exert
itself except in particular cases. Fixed air, or carbonic acid, is
composed of the base of oxygen united with a certain portion of carbon,
and the whole volatilised by the ethereal fluid. Phlogisticated air,
azote, or septon, according to Dr. Priestley, consists of the basis
of dephlogisticated air along with a certain proportion of carbon
different from that which produces fixed air, volatilised by the same
agent;[90] and so we may determine concerning every other species of
air.

  [90] See Medical Repository, vol. ii, No. iii.

5. In certain cases the ethereal fluid quits those substances with
which it is united: the air is then decomposed, the substance into
which the other fluid enters is heated, or rendered more fluid than
before (perhaps both) while the basis either unites itself to the
moisture of the lungs, or is thrown out by the breath. Whether in any
case the basis can pervade the membranes, and thus mix itself with the
blood, notwithstanding the positive assertions of Dr. Girtanner and
others, is very doubtful, and does not admit of any positive proof.

6. The blood, being a _fluid_, must be subject to the same laws with
other fluids. A certain quantity of _latent_ heat must be contained
in it, in order to give the degree of fluidity naturally belonging to
it. If this quantity be augmented, the fluidity will be augmented, and
the blood will become thinner; if it be diminished, the contrary will
take place; and if we suppose a great proportion of this latent heat to
be abstracted, it is not unreasonable to suppose that something like
a congelation may take place, and the blood be changed into a solid
substance of such a nature as cannot any more be made to resume its
former qualities.

7. By augmenting the sensible heat, the blood is affected in the same
manner as any other fluid; it suffers expansion, by which the vessels
are dilated in proportion, and, if this expansion and dilation be
carried to a certain length, a rupture of many of the small vessels,
and apoplexy, or some other grievous disease, may ensue.

8. By breathing certain kinds of air, the fluidity, heat and expansion
of the blood, and of consequence the dilation of the blood-vessels,
are affected. Thus, when a person breathes a quantity of the fume of
charcoal, containing much fixed air, he feels himself affected with
pain and a sensation of fulness in his head; he becomes sleepy, and,
if the quantity be sufficiently great, he falls into an apoplexy, and
dies. From dissections it appears that such as die in this manner have
the capillary vessels greatly distended, and even ruptured; the heat
of the body is vastly augmented, and even continues some time after
death. Hence it is evident, that, by breathing this kind of air, too
much _sensible_ heat is conveyed to the blood. In like manner when we
breathe the steam of water, if any quantity of that steam be condensed
in the lungs, the whole quantity of latent heat contained in that
steam discharges itself upon the lungs, and increases the sensible
heat of the body; and from this we may learn why on some occasions
our sensations should so ill correspond with the thermometer, and why
a warm air almost saturated with moisture should always appear much
hotter than a dry one, though the thermometer stand at an equal height
in both. Oxygen air seems to convey to the blood a much larger quantity
of what we have called _vital spirit_, than any other kind. Whether
this vital spirit be the same with the latent heat of the blood, we
know not; but, as this kind of air is evidently capable of supplying
the blood both with latent and sensible heat, it seems most probable,
that, by breathing a considerable proportion of it, both these kinds of
heat, as well as the vital spirit itself, will be augmented. In this
case, wherever the air naturally contains a larger quantity of oxygen
than usual, the blood ought to be mere fluid, as well as warmer, than
usual, provided there be no evident cause why it should be otherwise.
Accordingly in warm climates it is always found that the blood is
thinner and more fluid than in such as are colder; but at the same
time the temperature of the body is colder than in other countries.
Zimmerman tells us, that, “at Curassau, Europeans gradually lose their
fresh colour and vivacity: their natural heat even becomes three or
four degrees less than it was at their arrival.” The reason of this
last, however, is evidently the excessive perspiration, which is more
than sufficient to carry off the superabundant quantity of sensible
heat thrown into the body, either by the rays of the sun, or by the
superior quantity of oxygen naturally existing in the atmosphere; for
it is now found, contrary to the opinions hitherto received, that in
the warmer climates the atmosphere contains a larger proportion of
oxygen than in the more temperate.[91]

  [91] That this is the case with the atmosphere at Martinico is now
  determined by a letter from Dr. George Davidson to Dr. Mitchell of
  New York, inserted in the Medical Repository, vol. ii, p. 279. With
  equal parts of nitrous and atmospheric air there was an absorption of
  67 parts out of 100; but when two parts of atmospheric air were used
  to one of nitrous, the absorption was only from 52 to 58 parts; with
  a mixture of iron filings and sulphur, upwards of four tenths of the
  air were absorbed. These experiments were attested by a number of
  medical gentlemen who were present. In a letter subjoined from Dr.
  Chisholm, he says, that, having made a trial with iron filings and
  sulphur, the absorption was forty parts of an hundred, or exactly
  four tenths, with the eudiometer fifty-six. “It appears to me (says
  Dr. Chisholm) to be a singular circumstance, that, although the
  ground on which the Ordnance Hospital Hands is a perfect morass,
  partially drained, yet a result almost exactly similar to that given
  by the experiments made with the eudiometer at my house, should take
  place, with the same instrument and in circumstances very different.
  The proportion at the Ordnance Hospital, I think, has been 58 out of
  100, and at your house, a situation less swampy, and nearer the sea,
  it has been 67. An explanation of so singular a result, in situations
  so different, is perhaps more to be wished than expected.”

From this discovery it appears, that, whatever may be the cause of
the frequency and violence of epidemics in warm climates, it _is not_
the want of oxygen. Nay, we should rather be tempted to think that
they were produced by too great an abundance of it; and this the
more especially when we know that animals confined in oxygen air are
supposed to die of a burning fever; and it is likewise known that this
kind of air is prejudicial to consumptive people, and even brings on
the disease on those who had it not before. From the experiments
mentioned in the note, it seems probable that there are but few even of
swampy places in hot climates, where oxygen does not predominate; and
in these the heat thrown into the blood must still be augmented by that
produced from the quantity of vapour decomposed or condensed in the
lungs, which, as the condensation depends upon unknown circumstances,
can never be foreseen, or ever prevented, but by a removal from the
place.

With regard to other kinds of air, such as inflammable, phlogisticated
air, &c. experiments are yet wanting to determine their effects upon
people who breathe them habitually. The proportion in which they
occasionally exist in the atmosphere on particular occasions has not
been ascertained, and from the experiment made by Dr. Priestley with
offensive air taken from a manufactory, as well as from Dr. Chisholm
just mentioned, the probability is, that, even in the most offensive
places, the proportion of azote is by no means so great to the oxygen
that we could suppose the excess capable of producing a disorder of any
consequence, much less a violent epidemic. Fixed air is always produced
in the putrefactive process, and from its quality above mentioned of
rarefying and heating the blood, might reasonably be supposed to have
some share in producing epidemics, were it not that this kind of air is
so readily absorbed by water, as well as a number of other substances,
that, except at the very moment of emission, we can scarce suppose it
to have any considerable effect.

Mr. Watt in a letter to Dr. Beddoes gives an account of a kind of air,
seemingly more noxious than any yet discovered, which he produced by
distillation from flesh and from wool. The effects upon himself were so
disagreeable that he determined to make no more such experiments, lest
he should to his own hurt discover a mode of producing some grievous
disease. But we cannot, from an artificial air of this kind, argue to
a natural one; as the one produced by Mr. Watt was totally different
from any species of air naturally known. All that we can say is, that,
as far as we can trace the connexion between our bodies and the
different kinds of air which may be breathed, the latter act chiefly
by the heat they contain, and which they impart to the body in various
proportions; by which means the latent or sensible heat of the blood,
and consequently of the whole body, may be occasionally augmented
or diminished. Thus the body may be considerably altered in its
constitution, and rendered more liable to diseases than it was before;
but still it is found that diseases continue to appear at uncertain
intervals, though all the causes we are able to discover, or at least
all that are constantly evident to our senses, continue to operate
without intermission. Though the obvious qualities of air and climate
therefore may _predispose_ to an epidemic, we cannot affirm any thing
farther: the direct _cause_ is always different, and hath hitherto so
much eluded our researches, that we can have little hope of discovering
it, except by reasoning from facts less obscure.

8. In all the operations of nature which we have access to investigate,
the action of electricity is so much concerned, that we can scarce
suppose it to be wanting in any of them. That it is concerned in
preserving the health of the human body is likewise certain, if it
be the fluid which acts in the nerves, as most probably it is. But
whatever preserves health will also bring on disease, if it be applied
to that purpose; and we have already seen that this fluid is capable
of bringing on the most dreadful symptoms, viz. mortification in its
highest stage, fever, convulsions, bilious discharges, lethargy, &c.
If it be capable of producing all these, can we say that it is not
capable of producing those of an inferior kind, or of varying diseases
and symptoms without end, according to the immense diversity of its
action? It may be said that this disease was occasioned by a violent
stroke of electricity, similar to lightning; but how many people have
declared, that, in the beginning of some violent epidemics, they have
felt a sudden stroke at the time of seizure! Dr. Hodges mentions this
in the plague of 1665 at London, but treats the accounts as effects of
a distempered imagination. Procopius relates the same of the plague in
his time, viz. that many of the diseased felt a stroke. It is true that
they said such strokes were given by spirits in human shape, in which
we know they must have been deceived; but, though they were mistaken
in supposing that they had been struck by a spirit, it does not from
thence follow that they felt no stroke at all. The people mentioned
by Dr. Hodges did not say that they were struck by a _spirit_, yet he
treats their accounts with as great contempt as though they had. Where
people have no interest in deceiving, we ought certainly to look with
a favourable eye upon their testimony; for, even although some part of
it should be incredible, we have still reason to believe that there
is some foundation for what they say. Thus, the poor sailor, so much
frightened at the sight of a large bat in New Holland, was certainly
mistaken in saying that he had seen the devil; he was even mistaken in
saying that he had _horns_;[92] but from all this it would have been
doing him great injustice to say that he had seen nothing. In like
manner, when numbers of people in Procopius’s time said that they were
struck by spirits, when we find others in Dr. Hodges’s time saying that
they were struck by some invisible agent, when we know that electricity
_can_ strike in an invisible manner, it certainly is more reasonable
to conclude that violent diseases sometimes do begin by an electric
stroke, than that _all_ who said they were struck in this manner were
madmen or liars.

  [92] In the account of this sailor’s speech a most essential part of
  the devil’s character was omitted. The speech, according to Capt.
  Cook, was, that the devil “was about the size of a one gallon keg,
  and very like it. He had horns and wings; and he was so near, that,
  if I had not been _afear’d_, I might have touched him.” (See p. 105,
  n.)

It may now again be asked, if the plague, or violent epidemics, be
produced by electric strokes, why are they not much more frequently
felt, or by what are those milder diseases produced which are not
accompanied by any sensible stroke? Here we can be at no loss to say,
that whatever produces the highest disease, may also produce the
lowest. But, besides this argument, we have positive evidence that
commotions in the electric fluid will not only produce sickness, but
very extraordinary and seemingly miraculous effects upon inanimate
bodies. It has frequently been remarked that people are sick during the
time of earthquakes, when the electric matter is in violent agitation.
This has been accounted for from the motion of the earth, as the motion
of a ship produces sea-sickness. But Dr. Hillary mentions a slight
earthquake in Barbadoes where people were affected with sickness and
vomiting for _some hours_ after the phenomenon had ceased altogether;
which undoubtedly shows, that a certain state of this fluid will
disorder the human body, independent of every other circumstance,
either of the heat or cold of the atmosphere, or the oxygen, hydrogen
or azote contained in it. Again, we find that a certain state of the
electric matter is not only capable of producing very extraordinary
effects by itself, but also of communicating a power to the human
body to do the same. A good number of years ago, a powder-mill near
London was blown up. The explosion, as might be expected, was violent
and tremendous; but the most remarkable circumstance was, that the
electric matter, for a great way round, was thrown into unusual, though
invisible, commotions, which discovered themselves by the rattling and
breaking of china dishes though sitting apparently undisturbed upon
their shelves. This phenomenon did not suddenly cease, and, during
the time of it, some people appeared to be infected by an electric
_contagion_; the power of breaking china seemed to reside in their
bodies, so that if they approached or touched this kind of ware,
it would instantly fly to pieces. Accounts of this extraordinary
circumstance were published in many of the periodical works of the
time, particularly in Dodsley’s Annual Register; and the fact seems
to be established beyond controversy. It proves that what has been
advanced by Dr. Priestley concerning electrical operations, on a small
scale, holds good also on a large one, viz. that the fluid, when
once set in motion, is not easily quieted. It establishes the fact,
also, that by great explosions of gun-powder the electric matter is
violently agitated; and the consequence of these agitations we cannot
know. It may be said, indeed, that in the operations of nature the
electric matter is often violently moved without any sickness taking
place; neither in fact did any ensue at the time the powder-mill in
question was blown up. But it must be remembered, that, in the ordinary
course of nature, if the electric matter is moved, a receptacle is
also provided for it. In a thunder-storm, where immense discharges
of electricity are made from one cloud, there is another cloud of an
electricity opposite to the former ready to receive them, or if not,
the earth itself is frequently struck. In eruptions of volcanoes, the
smoke receives the electricity discharged, and becomes charged with
lightning of a more dangerous kind than that of ordinary thunderstorms;
and Sir William Hamilton relates, that in the great eruption of
Vesuvius, in 1794, lightning of this kind proceeded from the smoke for
no less a space than _seventeen_ days. But in artificial commotions
of this fluid, where nature has not provided any receptacle, the
phenomena must be quite different; and though we may with safety to
ourselves interfere with the operations of fire and electricity to
a certain degree, yet we may at last rouse these terrible elements
into such action as will prove fatal to great numbers. Hence possibly
may arise in part some of those sicknesses which take place after
battles, in violent sieges, &c. An instance of this is said to have
happened at Valenciennes, when last besieged by the Duke of York. A
disease prevailed chiefly among women, children, and persons of a weak
constitution; great numbers of whom died so suddenly that it was at
first thought to be a plague, until it was found not to be infectious.
The blood was found greatly dissolved, and the physicians ascribed it
to the monstrous bombardment and cannonading which took place during
the siege. Such was the account published in some of the newspapers
of the time, and from the subsequent considerations it will not seem
improbable that such things may take place.

From the experiments of Mr. Bennet (an English gentleman who has made
several discoveries in electricity) it appears, that we can neither
brush a piece of chalk, open or shut a book, or do several of the most
trifling actions, without agitating this subtile fluid in a perceptible
manner. It is well known that in some cases we cannot stroke a cat’s
back without making the electric matter visible, and in some positions,
by putting our fingers near the ears of the animal, very pungent sparks
will be received. If then we can neither open or shut a book, if we
cannot stroke a cat’s back, or approach a finger to her ear, without
agitating the electric fluid, is it reasonably to think we could burn
a book, or kill a cat, without doing the same? Certainly it is not.
If we cannot burn a book or kill a cat without affecting this fluid,
it cannot be supposed that we can burn a house or kill a man without
producing a still greater commotion; and in proportion to the extent
of our devastations, and the multitude of our massacres, the invisible
agitation of this element must become still greater and greater. In
all these transactions it must be remembered that the fluid is forced
out of its natural mode of action; for electric matter is made for the
preservation, not the destruction, of life: but if, by long continued
and extensive application of its power to a contrary purpose, we in
some measure pervert its action, no wonder that we then feel the
consequences of our own proceedings by its partly turning its power
against the human race altogether.

Again, the human body is not made for the habitation of an infernal
spirit, but for one of a quite different character. The boisterous
passions of fury, discord and hatred ought never to disturb the
mind, which is made for the habitation of endless peace and joy. The
tumultuous passions are enemies to health; and this is so well known
to physicians that they are very careful to prevent their patients
from being any way ruffled or disturbed by violent passions. It is
true these passions act upon the rational soul, which we may suppose
to be distinct from that merely animal spirit, probably no other
than the electric fluid, which runs along the nerves; but experience
shows that each of these can act upon the other; a disorder in the
body, particularly in the nervous system, will sometimes disturb the
rational soul in such a manner as almost entirely to deprive it of
all its faculties; while on the other hand a violent commotion in the
rational soul may at once extinguish all the powers of life, as has
already been shown from Zimmerman. Now, let any one consider what
must be the sensations of those who engage in war. Whatever pity or
humanity may be pretended, it is evident that in the day of battle all
these sensations must give way to horror and fury on the part of the
conquerors, and terror and dismay on that of the vanquished. That these
passions never do entirely subside, is evident from the treatment of
conquered countries and conquered people. When Jenghiz Khan beheaded
his prisoners by hundreds of thousands, when Tamerlane pounded them in
mortars, when Khouli Khan caused those who offended him to be carried
from place to place, and a piece of flesh to be cut from their bodies
at each stage, what must have been the sensations of these miscreants,
and those whom they employed in such horrid scenes? On the other hand,
what must be the sensations of those who see their dearest relations
torn from them and slaughtered or treated even worse than if they were;
themselves driven from their peaceable abodes to wander like beasts,
while their cruel enemies exult in the miseries they have brought upon
them, and glory in doing all the mischief they can, and spreading
devastation as wide as possible? Thus, every passion, inimical to
health, must, on both sides, be carried to its utmost height; and if
these horrid scenes overspread a great part of the earth, for hundreds
of years together, is it any wonder that plagues should ensue? If man,
forgetting the dignity of his nature, converts the habitation assigned
him by his Maker into a kind of hell, and himself into a devil, can
we wonder that, in such circumstances, the spirit of life, originally
appointed for his use, should become to such a being the spirit of
death? Dr. Moseley seems to speak slightly of Helmont for assigning
_moral_ causes to fever; but if we consider the matter attentively it
will certainly be found that the moral conduct of the human race in
general has more connexion with the diseases which befal them, than we
are perhaps willing to believe.

Most authors speak of some hidden, unknown and unsearchable power in
the atmosphere as the occasion of plagues and other epidemics; and,
from what has been already laid down, it seems by no means improbable
that this hidden power resides in the electric part of it. But we
know that electricity proceeds from the earth, as well as from the
air; so that in some countries the evaporation of electric matter
from the earth may affect the health of the inhabitants, as well as
the constitution of the atmosphere. Hence some spots may be naturally
unhealthy, and incurably so, independent of either the perceptible or
imperceptible properties of the air; their healthiness may occasionally
increase or decrease by means entirely beyond the reach of our
investigation. Here then our inquiries must stop. We may indeed make a
general conjecture that such differences are produced by the action of
the electric matter; but, unless this action be pointed out, and some
connexion traced between the situation of the country and a particular
mode of action of the fluid, we may as well own our ignorance at once.

9. From all that has been said, then, we may conclude, that none of the
obvious properties of the atmosphere, or of any constituent part of
it, or of any variation in the proportion of its ingredients, can be
accounted the cause of epidemic diseases; that the hidden constitution
of the atmosphere may with probability be attributed to the agency of
the electric fluid, and that by the action of this secret cause, along
with the other more obvious properties of the air, such as heat or
cold, moisture or dryness, &c. the human body may be so predisposed to
diseases, that they will readily break forth; and that the conduct of
mankind themselves may greatly contribute to this predisposition; the
question then is, supposing every thing to be thus laid, like a train
of gun-powder, what is the spark which first sets it on fire. Does the
disease arise spontaneously in the first person affected by it, or does
it come from without?

In answer to this we must in the first place observe, that the accounts
of all plagues mentioned in profane history trace their progress from
one place to another; whence the probability is, that at its origin the
disease was confined to a few, perhaps to a single person. In very few
cases, however, has it been possible to trace it to an individual; and,
even when this has been done, the unfortunate individual is always said
to come from some other place. The instance quoted from Dr. Moore is
perhaps the only one upon record where the plague arose spontaneously
in any person separated from society; and from a single instance little
can be inferred. In those terrible examples we have given of people
being burned to death without any accident from terrestrial fuel, the
agent seems almost certainly to have been electricity. In the plague of
Procopius, said not to have been infectious, the strokes complained of
by many patients seem to indicate an action of the same fluid. The same
in the plague at London, which was infectious, and likewise of others.
But, in cases of plagues which are not infectious, another question
arises--By what means do such diseases spread from place to place?
for even this dreadful pestilence of Procopius did not overspread the
earth at once, but is said to have begun at Pelusium in Egypt. To this
no answer can be given. To suppose an omnipresent contagion in the
atmosphere, proceeding either from contagion or any thing else, cannot
be admitted; for upon this supposition the whole world must have been
infected at once. The cause, whatever it was, plainly moved from one
place to another, or was successively generated in different places.
Recourse may be had to the precipitation of the contagious matter
of former plagues from the atmosphere; but to account for this in
succession will be found very difficult; and the same difficulty will
attend every other solution which may be attempted. Mr. Gibbon indeed
censures Procopius for supposing it not to have been infectious; and
perhaps the spreading of the disease by infection is the only way by
which we can account, in a satisfactory manner, for the way in which
it diffused itself over the world, which was, by first infecting the
maritime places, and afterwards those which were more inland; always
visiting the second year those whom it had spared the first.

10. Lastly, to form some idea of the nature of contagion, or infection,
as it is more properly called, we must consider, that as the ethereal
fluid, acting as heat, pervades the human body, so doth it likewise
under that particular modification which we call electricity. Some
kinds of air, indeed most of those with which we are acquainted, seem
to act by augmenting or diminishing the latent or the sensible heat of
the body. Such, when taken in moderate quantity, may produce slight
diseases, as head-ach, &c. and, when taken very largely, may even put
an end to life at once, either by rarefaction of the blood and rupture
of the small vessels, as is the case with fixed air, or by oppressing
the lungs entirely with their basis, which cannot be thrown out by the
breath as in ordinary respiration. Others may affect the electricity
of it, or what in this treatise has been called the _vital spirit_,
as well as the latent or sensible heat. The consequence of this will
be diseases of a more serious nature; for upon this principle in all
probability depend not only the secretion and proper regulation of
the nervous fluid, but what has been called the _crafts_, or proper
consistence of the blood and other fluids. Hence it is possible that
such an instantaneous shock may be given to the body, as will not only
injure the organization in an irreparable manner, but may be felt
throughout the whole body like an electric stroke, even though there be
no visible fire, or sensation of burning, as in the case of the Italian
priest and others, who perished in such a miserable manner.

Formerly all acute diseases were supposed to depend on morbific matter
taken into the body, and absorbed by the blood: the cure was thought
to be accomplished by the expulsion of this morbific matter from the
body by sweat, or some of the other natural evacuations. The doctrine
was attended by many difficulties, and in many cases did not admit
of a satisfactory explanation. It was therefore laid aside, and the
debility or excitement of the nervous system arose in its place. But
this new system admitting of _miasmata_ and _contagion_, it was plain
that morbific matter still kept its ground. With a view, it would seem,
to render the nervous theory more complete, it has been found necessary
to deny the doctrine of contagion and infection entirely. This has
been done, wherever there was a possibility; but the phenomena of the
small-pox and measles, as well as those arising from poisons, still
militated strongly in favour of morbific matter. To avoid the force
of arguments drawn from these sources, the doctrine of absorption was
denied, and contagions of all kinds were said to act immediately upon
the nervous system without affecting the blood or other fluids. At last
the matter seemed to be decided by the experiments of the Abbe Fontana
on poisons. He found that some proved fatal by being mixed with the
blood, others by being applied to the nerves, and others by being taken
into the stomach. Even this did not give satisfaction. It was contended
that the effects of poisonous bites were too quick to be accounted for
on the principle of absorption; that, after the most violent symptoms
had commenced, they might be removed by cutting out the part affected;
and consequently that, instead of any absorption by the blood, we were
only to believe that the nervous system was irritated.

“Poisons, (says Dr. Girtanner) remedies, and, in general, all
surrounding bodies, acting only on the irritable fibre, it follows that
they act upon the system in a similar manner, and that every substance
capable of producing the greatest possible effect upon the fibre, that
is to say, every substance capable of exhausting all the irritability
both of the fibre itself and of the system, in an instant, as for
instance, laurel water, or white arsenic, is also capable of producing
all the inferior degrees of action, either by acting on a fibre less
irritable, or by acting upon the same fibre, but in a less quantity.
Laurel water, opium, white arsenic, ammoniac, are of course both
medicines and poisons capable of _healing_, as well as of _producing_,
_all maladies whatsoever, without exception_.[93] And this is
confirmed by a number of experiments which I have made upon different
animals. This _truth_ seems to me _of the utmost importance_; and the
Abbe Fontana, who made more than six hundred experiments to prove that
ammoniac is no remedy against the bite of a viper, would have saved
himself the trouble, had he known it. If, instead of applying the venom
of the viper to so many animals, and afterwards applying ammoniac to
the wound, he had made a single comparative experiment, and applied
ammoniac to a wound made by a lancet that was not poisoned, he would
have found that ammoniac itself, applied in this manner, would have
produced a disease exactly analogous to that caused by the venom of
the viper; and, consequently, so far from removing the malady, must
necessarily increase it, by exhausting the irritability of the fibre in
a much less time than the venom of the viper by itself was capable of
doing. Mr. Fontana has made more than six thousand experiments upon the
poison of the viper; he employed more than three thousand vipers, and
caused to be bit more than four thousand animals; and the conclusion
he drew after this truly enormous number of observations was, that
the poison of the viper kills all animals, and produces the disease
by its action on the blood. But why did Mr. Fontana neglect to make
the decisive experiment, the _experimentum crucis_ of Bacon? It is
well known that frogs, and many animals with cold blood, live a long
time without the heart, and entirely deprived of blood. If therefore
the poison of the viper kills animals by its action on the blood, it
will not destroy frogs without blood. But experiment contradicts this
reasoning. The poison of the viper will kill frogs without blood in
as short a time as it kills those animals who have not lost their
blood. It is not therefore by its action upon the blood that the
venom of the viper destroys animals; and thus does it happen that a
single experiment frequently overturns all that _six thousand_ other
experiments have apparently established. According to my experiments,
poisons operate upon the blood just as they do upon the muscular fibre,
by depriving it of its principle of irritability, or of its oxygen.
After having made this observation upon the experiments of Mr. Fontana,
I must do him the justice to add, that I have found all his experiments
very accurate, and that in all those which I have repeated, the result
has been exactly conformable to the account given by him; it is in his
conclusion only that he appears to be deceived.”

  [93] This is an assertion so extravagant, that is difficult to
  imagine what could induce any one to make it. Did our author ever
  hear that laurel water, &c. produced the venereal disease, the
  plague, yellow fever, gout, stone, small-pox, &c. &c. or to what
  patients and in what diseases did he ever administer this remedy
  with success? I mean not to deny that these substances will cure
  _some_ diseases as well as produce others; but such an unqualified
  expression that they can not only produce but cure all diseases
  without exception, never can be admitted.

On this I must in the first place observe, that since _philosophers_
and _truth_ seem to be so far distant from each other that even _six
thousand_ experiments cannot bring them together, it were greatly to
be wished that in their researches they would pay a little more regard
to humanity. If the Author of Nature has set man at the head of the
creation, if inferior animals must patiently resign their lives to
preserve ours, are we therefore authorised to torment and put them
to death by thousands for every idle whim that comes into our heads?
After Spallanzani, Fontana, Girtanner and a multitude of other learned
_barbarians_ had cut in pieces, boiled alive, poisoned and tortured
thousands of inoffensive animals, new massacres it seems must be made,
and new tortures inflicted, because an _experimentum crucis_ is still
wanted! If knowledge is to be obtained only by such means as these, it
certainly must be derived from a very polluted source.

2. The experiment on which Dr. Girtanner builds so much is far from
being above suspicion. Though we may cut the heart out of an animal,
and let it bleed as freely as possible, yet we certainly overrate our
abilities if we say that _all_ the blood is taken out of it. The more
perfectly an animal is bled, the less irritability it has; which gives
a reasonable suspicion, that, if _all_ the blood could be taken away,
the irritability would cease entirely. In frogs, and all other cold
blooded animals, the blood contains fewer red globules than in such as
are warmer; the circulation is more languid than in such as have warm
blood, and, of consequence, the blood will retain its irritability
for a longer time, and it will likewise be more difficult to deprive
the body of all its blood. In making this experiment, therefore, Dr.
Girtanner ought to have brought unexceptionable proofs that he had
deprived the frog of _all_ the blood it contained. But, as this was
not done, we shall be ready to suspect that some was left; in which
case we should be still as uncertain as before whether the poison acted
on the irritable fibre, or on the blood. But the decisive experiment,
or _experimentum crucis_, seems to have been made by Fontana himself,
by injecting a little of the diluted poison of the ticunas into the
jugular vein of a rabbit. Here the poison was applied to the blood
itself. It could get at no other part of the fibre but the inside of
the vein, which is not accounted very irritable; and the quantity
injected was so small, that the Abbe thought his experiment had
failed; yet the animal died as if by lightning. The moment he turned
his eyes towards it, it was absolutely dead, without discovering the
least convulsive agony, or other sign of some little life remaining,
generally observable for some time in animals killed by the common
methods. On applying the same poison to a large nerve of another animal
of the same species, no injury followed.

3. The dispute is of no consequence, and the experiment will prove the
same thing whether we suppose the poison to act upon the irritable
fibre (the nerves and muscles) or upon the blood. The only important
point to be ascertained is, whether there be in nature any substance
which, applied to the internal parts of the body, or to a wound, will
instantly disorder the whole in such a manner as to bring on a violent
disease which may prove mortal in a short time. If any such there is,
that substance, whether solid or fluid, visible or invisible, may with
propriety be called _contagion_; and if any such proceeds from the
body of a diseased person to one in health, the vapour so proceeding is
_infection_. As to the _mode_ of its operation we are little concerned;
the sudden manner in which people are affected shows that poisons
kill by suppressing in a very short time the principle of life, which
seems to be analogous to electricity, or rather the very same with
it; neither is it more incredible that the poison of a serpent should
kill by disturbing the natural electricity of the body, than that the
stroke of a torpedo, or electrical eel, should kill by the same means.
The only difference is, that, in the case of poisons, the pernicious
substance is introduced into the body itself; in the torpedo, it comes
with violence from without. The former we may compare to the silent
discharge of an electrified jar by a point, the latter to its discharge
with a violent flash by a knob. But that in poisonous bites the blood
is greatly affected, and that in a very short time, we certainly know.
There are some kinds of serpents whose bites are so suddenly fatal,
that no cure can be applied: one of these, called the small _laharra_,
is mentioned by Mr. Bancroft in his Natural History of Guiana. Mr.
D’Opsonville, in his Philosophic Essays, takes notice of one in the
East-Indies, which he calls the _poison serpent_ or _serpent poison_,
which seems to be as bad as the _laharra_ mentioned by Bancroft. This
too is but small, viz. two feet long, and very slender. Its skin is
freckled with “little traits of brown, or a pale red, and contrasted
with a ground of dirty yellow: it is mostly found in dry and rocky
places, and its bite proves mortal in less than one or two minutes. In
the year 1759, and in the province of Cadapet, I saw several instances
of it; and, among others, one very singular, in the midst of a corps of
troops, commanded by M. de Bussy. An Indian Gentoo merchant perceived
a Mahometan soldier of his acquaintance going to kill one of these
reptiles, which he had found sleeping under his packet. The Gentoo flew
to beg its life, protesting that it would do no hurt if it was not
first provoked; passing at the same time his hand under its belly, to
carry it out of the camp; when suddenly it twisted round, and bit his
little finger; upon which this unfortunate martyr of a fanatic charity
gave a shriek, took a few steps, and fell down insensible. They flew to
his assistance, applied the serpent-stone, fire, and scarifications,
but they were all ineffectual; his blood was already _coagulated_.[94]
About an hour after I saw the body as they were going to burn it, and I
thought I perceived some indications of a _complete dissolution of the
blood_.”

  [94] There must certainly be some error here; for as he mentions a
  _dissolution_ of the blood so soon afterwards, we should think it
  impossible that any coagulation would have taken place. Perhaps the
  word only imports that the circulation was completely stopped.

The bite of the _brulan_ or _burning serpent_, according to the same
author, is almost as terrible. “This is nearly of the same form with
the last, its skin is not quite so deep a brown, and is speckled with
dark green spots: its poison is almost as dangerous, but it is less
active, and its effects are very different. In some persons it is a
devouring fire, which, as it circulates through the veins, presently
occasions death; the blood dissolves into a lymphatic liquor resembling
thin broth, without apparently having passed through the intermediate
state of _coagulation_,[95] and runs from eyes, nose and ears, and even
through the pores. In other subjects the poison seems to have changed
the very nature of the humours in dissolving them; the skin is chapped
and becomes scaly, the hair falls off, the members are tumefied, the
patient feels all over his body the most racking pains, then numbness,
and is not long in perishing.”

  [95] The blood certainly does not coagulate in the vessels, in any
  case whatever, unless by injecting something into them.

From these accounts it is plain that poisons do operate very powerfully
on the blood; and if they do so in one case it is reasonable to think
that they do so in all. According to the degree of strength of the
poison, however, we are sure that the effects will be more or less
visible to us; but, though we should not be able to perceive any
alteration whatever in the consistence or colour of the vital fluid, we
cannot positively say that it has not undergone any change; for the
spirit which operates in it is too subtile for our observation. In the
beginning of almost all diseases, perhaps, blood drawn from a vein will
not be perceptibly different from that of a person in health; and Dr.
Fordyce particularly takes notice of this in fevers; but as the disease
goes on, an alteration becomes very perceptible, which gives just
ground for suspicion, that there had been some alteration from the very
first, though invisible to us.

After all our disputes, however, we shall find that the controversy,
though ultimately important, begins more about words and trifles than
any thing else. Dr. Brown used the word _excitability_, Dr. Girtanner
uses _irritability_, and the author of this treatise, the words _vital
spirit_ and _electricity_, to express something equally unknown to
them all. The only difference is, that Drs. Brown and Girtanner speak
of their excitability and irritability as a kind of power essentially
inherent in living bodies, acted upon indeed by certain substances,
but incapable of deriving any supply from without; the author of this
treatise considers it only as a modification in the human body, or an
_organization_, if we please to call it so, of that fluid which he
believes to be universally diffused, under the names of heat, light
and electricity. Hence that portion modified or organized in the human
body must be under an entire and absolute dependence upon the immense
mass of surrounding fluid, and, by any alteration in the motions of it,
must be often very perceptibly affected; nevertheless as this fluid was
originally created to preserve and not to destroy human life, there is
much less danger from a _natural_ than from an _artificial_ commotion
in it. In some visible bodies, such as poisons, the fluid acts in such
a manner as to counteract the operation of that part which is organized
in the blood or nerves, or both. Hence on the introduction of such into
the body the disorder flies like lightning through all parts of it,
and in a very short time brings on death. In those vapours properly
called _contagions_, the opposite action is less violent, and therefore
the disorders they produce are in proportion. Hence such diseases may
either be promoted or retarded by the perceptible properties of the
atmosphere, which in poisons have little or no effect. There is indeed
a remarkable difference in the strength of the poison secreted in the
bodies of serpents at certain seasons of the year, or according to
their food. M. D’Opsonville observes that the poison of serpents is
in general more powerful, the more they live in hot and dry places,
where they feed upon insects that are full of saline, volatile and
acrimonious particles. But, notwithstanding this difference in the
strength of poisons according to the circumstances of time and place,
there is not the least reason to suppose that poison of a given
strength would not produce the very same effects, let the state of the
atmosphere be what it would.

If therefore we certainly know that there are some kinds of aerial
vapours which when applied to the human body do exert a power directly
opposite to the vital principle, there is no reason to doubt that
such vapours may be confined among certain soft substances, such as
cotton, wool, &c. and remain there for an unknown length of time,
again exerting their malignant powers, when a fresh object comes in
their way. Besides, as all kinds of air with which we are acquainted
consist of a basis united with the ethereal fluid and volatilised by
it, there is reason to suppose that contagions themselves are formed
in the same manner. Some kinds of air also are very easily decomposed,
in which case the basis attaches itself to some terrestrial substance,
the ethereal fluid which volatilised it diffusing itself around in an
invisible manner, but generally with a perceptible heat. Fixed air
affords a notable example of this; for, by exposing it to lime-water,
or even dry lime, alkaline salt, volatile alkali, or common water, a
decomposition of the air very readily takes place, and its basis is
found to be attached to those substances. What happens to fixed air
may also happen to _contagion_. The basis of it may have a tendency
to unite itself to cotton, or such like substances, and thus may
not only infect them, but concentrate itself to such a degree as to
produce a disease much more violent than that of the person who gave
the infection; and something of this kind has even been observed with
regard to infected cotton. But now another question occurs: As fixed
air, by being attached to terrestrial substances, loses its aerial
property, why should the basis of contagious effluvia still retain its
malignant quality though in a state of decomposition? Here we are again
helped out by analogy. Fixed air is known to be capable of resuming
its aerial properties occasionally, from causes unknown to us, though
we cannot suppose them to be any thing else than the invisible action
of the ethereal fluid so often mentioned; which, being guided by laws
unknown to us, we cannot possibly comprehend. The fact, however,
is certain, that the basis of fixed air does very often quit the
substances to which it is attached, and assume an aerial state in great
quantity, and with very mischievous effects. Thus the old lavas of
volcanoes, if chemically tried will be found at _all_ times to contain
great quantities of the basis of fixed air, but it is only at _some_
times that the mofetes which are supposed to be the air itself, break
forth.[96] In like manner the strata under ground always contain great
quantities of the aerial basis, but the _damps_ in mines, which are
certainly known to consist mostly of fixed air, do not always appear;
neither do they gradually accumulate, but come suddenly, spreading
unexpected destruction among those who unfortunately come in their way.
The same may take place with contagion. After remaining some time in a
state of decomposition it may have a tendency to become volatile again,
or it may lie dormant entirely; and this last will explain what is
quoted from Dr. Russel, p. 178, that sometimes commerce may be carried
on with infected places without danger.

  [96] See p. 128, note.

Thus we see that the dispute, originally begun about a word, involves
at last a matter of the utmost importance; for, if it be found
unreasonable to believe that any such thing as contagion exists or can
exist, it follows of course that it is also unreasonable to take any
precautions against it. Mr. McLean even goes a step beyond those who
deny the existence of contagion; for we find him also denying that
putrid effluvia can produce epidemics; according to which doctrine, it
seems, we may not only safely visit places accounted the most dangerous
on account of infection, but live in all manner of filth and nastiness
with impunity. It is plain that no person can ever prove that it is
impossible for contagion or any thing else to _have an existence_.
Indeed if nothing had ever induced people to believe that it did exist,
it would have been superfluous to say any thing about it. But when we
have innumerable testimonies to the contrary; when the opinions of the
greatest physicians, as Dr. Lind, Dr. Clarke, Dr. Mead, Dr. Sydenham,
Dr. Fordyce, Dr. Russel, &c. agree that not only the plague, but every
kind of fever, is infectious; when we know from the analogy of nature
that contagion _may_ exist; when we know that there certainly _are_
powers in nature able to produce it; is all this to be thrown aside
merely on the strength of a theory, and a theory too which can never
be proved? for it is impossible to prove the _non-existence_ of any
thing, much less the _impossibility_ of its existence. The lives of
mankind are too precious to be sported with on philosophical theories;
and prudence will always suggest, that wherever danger may at any time
arise, there it is proper to be on our guard.

Dismissing at length the subject of contagion in general, we now enter
upon the question, Whether doth it appear from fair investigation of
testimony, that the plague has, at any time, been communicated by
contagion or not? And here I shall confine myself to what has been
adduced by Dr. P. Russel on the subject; for, if we find that the
disease has only _once_ been introduced by contagion, it signifies
nothing though we were able to prove, which we never can do, that it
had been _an hundred_ times bred in some other way. The matter is of
too great importance to allow even a _chance_ of its importation by the
neglect of the precautions necessary to prevent it.

Our author begins with observing, that though the infectious nature
of the plague had been a question much agitated in the schools, “it
was less to be expected that physicians who had been engaged in
practice among the infected should have persisted in the opinion that
the disease was never communicated by contagion.” Such, however, has
been the case. In 1720 some French physicians laboured exceedingly to
prove that the plague which then raged at Marseilles and throughout
Provence arose from corrupt humours bred in the body in consequence
of irregularity in the seasons, and bad aliment; that it was spread
by the same means, in concurrence with terror, grief, despondence,
or other debilitating affections of the mind; but was neither bred
nor disseminated contagion. Dr. Russel mentions in a note, seemingly
with surprise, that “_so late_ as the year 1778, Dr. Stoll of Vienna
should have written expressly against the doctrine of pestilential
contagion.” To this professor he thinks it a sufficient answer to quote
the following passage from Mr. Howard on Lazarettos, “It must appear
very strange, that he should go back to Livy’s Roman History for proofs
to establish his point, totally neglecting all the facts concerning the
numerous visitations of the plague recorded in modern medical books,
or which had happened during his own time. I suppose professional men
will lay very little stress upon all that can be said on pestilential
diseases, in general, which happened in wars and sieges two thousand
years ago, as applied to the plague properly so called, a disease
then confounded with various others from which the accuracy of latter
observations have sufficiently distinguished it.”

Dr. Russel complains of the French physicians at Marseilles having
made unfair representations; particularly that while they produce as
irrefragable arguments against contagion their own escape unhurt, amid
circumstances of supposed danger, they pass slightly over, or omit
all mention of numbers of the medical assistants whom they saw perish
in the exercise of their profession. M. Dedier, however, who at first
opposed the doctrine of infection, at last renounced his opinions so
far as to allow that the disease might be communicated to dogs by
injecting pestiferous bile into their veins; and he likewise admitted
that it might be communicated from one human creature to another, by
drawing in for a considerable time the breath of a diseased person,
putting on his shirt, lying in the same bed-clothes, and touching the
wounded parts of one’s own body with hands embrued with the sweat or
blood of one infected. He affirms, however, that the atmosphere of a
person in the plague is no more to be dreaded than that of a venereal
patient; and that the touching or dressing of buboes or carbuncles
is not attended with any danger. He restricts the infectious quality
of the humours to the bile; but the _inoculation_ of a person by the
matter of a pestilential ulcer[97] undoubtedly decides this point
against him.

  [97] See p. 196.

On the subject of contagion Dr. Russel observes, that the vague manner
in which the word has been used has given rise to much confusion. Some,
taking advantage of the inaccurate mode of expression on this subject
used by Dr. Mead, attacked him with sophistical nonsense. The following
may serve as a specimen, from a pamphlet entitled “Distinct Notions
of the Plague, &c. by the _Explainer_.” This _explainer_ observes,
that, according to Dr. Mead, “air and his other causes propagate and
spread contagion, not the plague; and therefore either contagion and
the plague are the same, or else the plague is not considered; if the
first, then his causes propagate the plague; and the plague accompanies
the plague; an excellent defence! But, if the plague is out of the
play, then contagion accompanies nothing.”--From writers like this we
certainly can expect nothing.

The opinion of Dr. Cullen concerning contagion has been already
noticed, p. 179; but though he supposes it to be a matter floating in
the atmosphere, he observes that contagions are never “found to act
but when they are near to the sources from whence they arise; that is,
either near to the bodies of men, from which they immediately issue,
or near to some substances which, as having been near to the bodies of
men, are embued with their effluvia, and in which substances these
effluvia are sometimes retained in an active state for a very long
time. The substances thus embued with an active matter may be called
_fomites_; and it appears to me probable, that contagions as they arise
from fomites, are more powerful than as they arise immediately from
the human body.” This opinion concerning the great power of contagion
imbibed by certain substances is conformable to what was above laid
down by reasoning _a priori_ on the nature of contagion.[98] It is
doubted by Dr. Russel, but Dr. Lind adopts it, and Van Swieten gives
his opinion to the same purpose. “I am convinced, that the body of the
diseased, kept exactly neat and clean, is not so liable to impress the
taint, as his late wearing apparel, dirty linen, and uncleanliness of
any sort about him long retained in that impure state. I say, these
last contain a more concentrated and contagious poison than the newly
emitted effluvia or excretions of the sick.”

  [98] See p. 226.

With regard to the original cause, our author observes, “that the
plague is bred or produced originally from vitiated human effluvia, is
a matter which has by no means been established on proper authority.”
Setting aside therefore inquiries of this kind, he thinks it sufficient
to inquire whether the infection be not communicated from a sick to a
sound person by immediate contact; whether it be not also communicated
at some distance through the medium of the air; and whether substances
of various kinds do not imbibe the infectious effluvia, and retain them
for a considerable time. So far as these points admit of proof from
the experience of times past, the question concerning pestilential
contagion will admit of a solution, independent of all theoretic
reasoning whatever.

2. On the subject of contagion people have been embarrassed by
confounding the true plague with other malignant diseases. This
has been done, not only by the ancients, but by some moderns; and
our author quotes Dr. Pye, saying “that any epidemic sickness,
which rages with more than ordinary violence, and which occasions
extraordinary mortality amongst mankind, may be, and is, properly
termed a pestilence, or the plague.” By not attending to the proper
distinctions, in these cases, circumstances belonging to what are
commonly termed malignant or pestilential fevers will often come to be
very improperly applied to the true plague.

3. “It may be remarked, that those who contend in favour of contagion,
from zeal for accumulating proofs, have collected a number of
facts from historical records of very unequal authority, and often
with little critical skill in discrimination. Of this error their
antagonists availing themselves, have selected from the mass the
instances most liable to doubt or objection, and have endeavoured, by
their manner of arranging them, to place the whole in a ridiculous
light; while more important instances are either evasively past over,
misstated in the representation, or invalidated by general declamation
on the little credit due to historians in matters of physic, or
the prejudices prevalent in ancient times of ignorance, and on
contradictions to be found in the arguments of those who support the
system of contagion.”

To this the Doctor adds the great quantity of hypothetical reasoning
which has been introduced into the controversy, and above all the
unfair dealing of the parties in carrying on the dispute, which has
reduced the matter from “a calm inquiry in pursuit of truth, to a
wrangling contest for victory.” Lastly he insists, that, had it not
been for the misrepresentations and sinister dealings of those who
have written against contagion, “the question seems to have been
properly resolved in the affirmative;” and he complains greatly of the
conduct of the Montpelier physicians in this respect, insomuch that
“their misstating of circumstances, and the partiality so evidently
discoverable in their narrative of cases, will serve more effectually
to remove doubts on the subject, than any arguments that could be used
against their hypothesis.”

On the subject of contagion our author observes, that some difficulties
still remain; but these, though proper subjects of future inquiry,
“do not appear to be of force sufficient to invalidate facts already
established. It is well known, that the same person who has been
inoculated two or three times for the small-pox without effect, even
in an epidemic season, has afterwards received the infection upon
repeating the operation at a distance of time when the disease was
hardly sporadic. The cause of this remains unknown; but ignorance of
it was never produced as an argument against the reality of variolous
contagion.... If, of one hundred persons exposed to the infection
of the plague by a near aproach to the sick, ninety should fall sick,
shall human inability to assign satisfactory reasons for the escape of
the other ten be converted into a positive proof against the disease
having been caught by contagion? If persons retired from all commerce
with the infected and their attendants, breathing the same air with
the rest of the inhabitants, and nourished by the same aliment, remain
untouched during the ravage of the plague, as long as they continue
secluded, but, upon unguarded communication, are taken ill like others;
can any rational doubt be entertained about the cause of their former
security? Or if through stealth, or neglect of requisite precautions,
substances tainted by the sick should be conveyed into these secluded
retreats, and persons living temperately as before, ignorant of what
had happened, and consequently in the midst of imaginary security,
happen to be seized with the distemper; can it with any show of
reason be ascribed, not to contagion, but to terror, or to colluvies
in the stomach and bowels, produced by intemperance and bad aliment?
The instances here alluded to are not the _creation of fancy_, but
_strictly consonant to repeated experience_ in Turky; to say nothing at
present of what has been observed at Marseilles and in various cities
in Europe.”

“But a greater difficulty than that of all persons not being equally
susceptible of the infection arises from the cessation of the plague,
at a period when the supposed contagious effluvia, preserved in
apparel, furniture, and other fomites, at the end of a pestilential
season, must be allowed to exist, not only in a much greater quantity
than can be supposed to be at once accidentally imported by commerce,
but in a state also of universal dispersion over the city: the fact,
however unaccountable, is unquestionably certain; the distemper seems
to be extinguished by some cause or causes equally unknown as those
which concurred to render it more or less epidemical in its advance
and at its height. In Europe something may be ascribed to the means
employed for the cleansing of houses and goods supposed liable to
retain the latent seeds of infection; but, at Aleppo, where the
distemper is left to take its natural course, and few or no means of
purification are employed, it pursues nearly the same progress in
different years: it declines and revives in certain seasons, and, at
length, without the intervention of human aid, ceases entirely.”

On this we shall remark in general, that the failure of contagion
in some cases to produce the usual effects may proceed from some
constitution of the body, disposing it not to allow the cause to
produce its usual effects at one time, though at another, the
constitution may be so far changed as very readily to admit it.
This opinion has been very generally received among medical people,
who have, to this singularity of constitution given the name of
_idiosyncrasy_. It is, however laughed at by Mr. McLean. “As the
fact (says he) cannot be denied, that a great majority have escaped
after contact with persons ill of diseases supposed to be contagious,
attempts may perhaps be made to account for it by supposing a certain
peculiarity of constitution, which exempts from, or disposes to,
disease. Is it the many who escape that have this happy peculiarity
of constitution; or the few who are seized that are so unfortunate as
to possesses it? The former are evidently too numerous to admit such
an hypothesis. The property must therefore, I conclude, be given to
the latter. But a child here and there is exempted from small-pox,
although exposed to its contagion. In order to preserve a consistency,
this fact must be accounted for by the same or another peculiarity
of constitution. Peculiarities of constitution, then, exempt from
contagion in one case, and dispose to it in another; and thus a
term, which in reality means nothing, may be made to account for any
thing. For my own part I confess my inability to comprehend any other
_peculiarities_ of _constitution_, or _idiosyncrasies of habit_, than
what are constituted by the different degrees of health and disease;
the different states of the excitability.”

In the same manner that Mr. McLean argues with regard to disease,
let us argue concerning bodily strength. Some men are able to lift
a weight of 6 or 700 pounds, but a great majority cannot lift above
300. Whence proceeds the difference? Is it the few who lift the great
weight that _by nature_ have _more_ strength, or is it the many who can
lift only the smaller that _by nature_ have _less_? This is precisely
his argument, and there needs no other refutation than stating it in
this manner. What he calls the states of excitability are as much
_idiosyncrasies_ at the time as any thing else. Mr. McLean will not
deny that a person debilitated by certain causes is more liable to be
seized with typhus fever than one who is not. What does this proceed
from, but that the body of the one is prepared for the disease, is
_constitutionally_ disposed to receive it, or has an _idiosyncrasy_ of
habit disposing to it, which the other has not? It is true, that unless
we point out the circumstances which constitute this idiosyncracy we
do nothing; but Mr. McLean’s scheme, of resolving every thing into
_excitability_, would forever prevent us from doing so. This is the
great deficiency of the Brunonian system altogether; for, by attending
only to the animal life of the body, he seems to have absolutely
forgot that we had any thing in common with vegetables. The bones,
for instance, or indeed any part of the body, cannot be formed by the
power which governs it after it was formed. The growth of the human
body is as strict vegetation as that of a tree; and therefore we find
that after the excitability is entirely gone, after death has taken
place for a considerable time, the body still retains its form, and
would do so forever, did not other powers interfere with it. Human life
therefore is a compound of the vegetable and animal life, the former
being the basis of the latter; and it is the vegetable life which is
much more commonly the subject of disease than the animal life. In
vegetables we observe an _idiosyncracy_ of habit, as well as among
animals. Some, even of the same species, are much more vigorous than
others, and, among some, diseases are much more common than others. In
like manner among the human race some are strong, others weak; in some
the blood is much more confident, and coagulates on exposure to the
air much more firmly than in others. Excitability, or excitement, is
common to all, and the degrees of it (though enumerated by Yates and
McLean in a kind of thermometrical scale) must be merely imaginary,
because excitability is not the object of our senses. The obvious
properties of the body itself, independent of any excitement whatever,
are principally to be considered in medicine. These constitute the
peculiar constitution, or the _idiosyncracy_ of habit, belonging to
each individual. Yet, in defiance of every confederation of these
obvious properties, which all have access to observe, the new system
leads us only to consider an invisible and unknown being called
_excitability_. Hence diseases peculiar to certain constitutions more
than others are said to be occasioned only by certain degrees of
excitability common to all, or perhaps to consist in these very degrees
themselves. Thus a peculiar mode of practice has been introduced, in
which almost the whole materia medica is rejected. We have already
quoted Dr. Girtanner, saying that _all diseases whatever_ may be
_cured_, as well as _produced_, by only _four_ articles; but in the
following quotation he goes still farther. “The art of pharmacy and
the science of prescription will become useless; a phial of alcohol or
laudanum will supply the place of that enormous quantity of drugs which
crowd the shops of apothecaries. The trade of the druggist----but hold;
if I continue this prophetic language, I shall only expose myself to
ridicule,” &c. Reveries of this kind certainly deserve the most severe
reproof. People may no doubt amuse themselves with _theories_ as well
as any thing else, while these theories continue inoffensive; but when
the belief of them leads to a rejection of what has been established by
the _experience_ of many ages, they begin to assume a consequence which
they originally had not. We have already seen that a disbelief of the
doctrine of contagion leads people into a practice accounted dangerous
by many, and which cannot be proved to be safe. A total rejection of
medicines, the efficacy of which have been attested by thousands, and
which never can be proved to have _no_ efficacy, must be attended with
still worse consequences, as thus we should be deprived of the means
of curing those diseases which our imprudence in rejecting the former
doctrine might have brought on. But, to return to the subject of the
plague.

The disappearance of the disease, while all the causes that we suppose
capable of producing it remain in full force, is a demonstration that
it depends on something entirely distinct from the human body, and from
all those powers which perceptibly act upon it. It proves that this
unknown power has only a temporary existence, coming to perfection
at one season, and dying away in another; sometimes capable of being
revived, and sometimes not. This corresponds entirely with what has
been laid down concerning contagion itself, viz. that like other
aerial vapours it is capable of decomposition, and remaining for an
uncertain length of time in a dormant state; but that occasionally it
may revive, and appear unexpectedly, as _mofetes_ arise from lavas,
or damps in mines. After a city has been thoroughly infected with a
pestilential disorder, therefore, there can be no security against its
re-appearance; it being impossible to know whether the contagion may
not be still existing and capable of being revived by some unknown
cause, though it has been dormant ever so long. In such cases it may
with propriety be said to have arisen _spontaneously_, though, had it
not been there at a former period, there could be no reason to think
that it would have appeared at that time.

Dr. Russel next takes into consideration the plague at Marseilles in
1720, of which he says the accounts “are more full, and circumstances
better authenticated, than most of the accounts of anterior plagues
to be met with in books.” From the opposition to the doctrine of
contagion at the time, he also supposes that the facts relative to its
introduction would be severely scrutinized, and falsehoods detected:
“but (says he) if, instead of such detection, the most material
have been passed over in silence, and little more than hypothetical
reasoning opposed to others, the main facts may be considered as
established, if possible, more firmly than they were before.” These
facts are stated as follows: “1. That the plague did not exist in
France before the 25th of May, 1720. 2. That it was imported in goods
from the Levant, by a ship which left the coast of Syria the beginning
of February, and arrived at Marseilles the 25th of May. Two days after
her arrival one of the sailors died; an officer of quarantine who had
been put on board died on the 12th of June, and a cabin boy on the 23d.
Some porters employed in opening the merchandise at the lazaretto also
died about this time. Three others were taken ill in the beginning of
July, with buboes in the groin and axilla. This alarmed the surgeon of
the lazaretto; a consultation was held with two other surgeons on the
28th; the disease was unanimously declared to be the plague, and the
three patients died next day: the surgeon of the lazaretto, with part
of his family, and the priest who attended the sick, were also taken
ill and died.”

From the lazaretto the disease made its way into the city, and began to
appear about the 20th of June. By what means it was introduced is not
directly said; but it seems to have been by smuggling infected goods.
In the beginning of July it began to spread; but a kind of pause having
taken place between the 12th and 23d, the physicians were reproached
with having mistaken the distemper. During this supposed interval,
however, it was discovered on the 18th of July that the disease had
spread in a certain part of the city. A surgeon, employed to examine
into the matter, declared the distemper to be the worm-fever; and
about the 23d the council of health were informed of the death of
fourteen persons in that quarter, and of several others falling sick.
The surgeon still adhered to his opinion, but a physician declared it
to be the true plague. About the end of the month it had got into the
suburbs; four physicians declared it to be the true plague, but their
report was not believed; they were insulted in the streets, and it was
not until some of the inhabitants of better rank were taken ill, that
the true state of the matter gained credit.

“Such (says Dr. Russel) was the rise of the plague at first, and
its progress afterwards in the months of June and July; whence it
appears, that persons on board the suspected ship, those employed in
airing the goods, a surgeon and a priest, who attended the sick, were
among the first infected; that the passengers from the several ships,
all of which ships, the first excepted, brought foul patents, were,
together with their baggage, admitted into the city, after preforming a
quarentine of little more than eighteen days; that the distemper from
the 20th of June till towards the end of July advanced very slowly,
and sometimes seemed to pause; that it attacked chiefly the poorer
sort of people, and was found in distinct quarters of the city; and
lastly, that, _during the first forty days, few or none of the infected
recovered_; a circumstance entirely consonant to what was observed in
the beginning of the plague at Aleppo.”

Three other facts are mentioned by our author, viz. that the disease
was evidently communicated by infection; that those who were careful
to seclude themselves from all communication with the sick and with
infected goods, were not infected; and lastly, that the disease, which
began to rage violently in August, continued to do so through that and
the following month, but declined fast in the months of October and
November, and seemed to cease in the middle of winter. Some accidents
happened in 1721, between the months of February and July, which gave
occasional alarm; but the distemper did not spread, and ceased entirely
after the summer solstice of that year.

To all this, however, objections have been made. 1. That the irregular
seasons of the former year, a bad crop, and unwholesome aliment,
had produced a malignant epidemic, all which, joined to the popular
dread of contagion, were sufficient to produce the plague without any
imported infection. To this Dr. Russel replies, that these positions,
assumed as facts, had no existence; for which he refers to the
publications of the times. 2. It was objected that there were instances
of the plague in Marseilles before the 25th of May. These instances are
only five in number, produced by M. Deidier, “who saw not the cases
himself, yet (says Dr. Russel) from the very imperfect accounts he had
been able to glean, he thought himself justified in declaring they bore
all the marks of the true plague. Nothing (adds the Doctor) but extreme
partiality to an hypothesis could have led any one practised in the
plague, into such a declaration; the cases bearing every internal mark
of belonging to a different class from the plague. I shall endeavour to
show this in a few words.

“Of the five supposed infected patients, three recovered, two died, and
all had eruptions. One who died had a parotis (the most ambiguous of
all pestilential tumours) without any concurrence, so far as appears,
of pestilential symptoms. The tumour had appeared six days before the
woman’s death, but how long she had been sick remains unknown. The
other died the 16th or 17th day, a very unusual period in the plague.
She also had a parotis, which did not make its appearance till the
10th or 11th day of the disease. No pestilential symptoms whatever
are mentioned. Of the three who recovered, one was very ill with a
fever and carbuncle; but neither the invasion nor the duration of the
disease are mentioned. Another had a carbuncle and a small tumour
on the thigh; and the third (which bears the nearest resemblance
to a very slight infection) had also a bubo in the thigh; but the
tumours in neither of these patients are described in such a manner
as distinguishes them from ordinary tumours; and the apothecary, who
gives the account from memory, had in all likelihood never seen a
pestilential bubo before.”

“Of the persons infected for some time after the arrival of the ships
from the Levant, none had eruptions, and all perished after a few
days illness; which agrees entirely with what was observed at Aleppo
in the beginning of the plague: hardly any of the sick recovered, and
the major part died in three or four days, without any appearance of
buboes. Upon the whole, therefore, I think it very clearly established,
that the plague did not exist in France before the month of May, 1720.
Prior to M. Deidier, however, I find a M. Pons had endeavoured to prove
that the plague was in Marseilles, not only before the month of May
1720, but even in the preceding year. I have not had an opportunity of
examining that gentleman’s book.”

3. It is objected that the disease was not brought from the Levant by
infected goods. “Captain Chataud’s vessel, supposed to have brought
the infected goods, arrived with a clean patent, or bill of health,
having left the coast of Syria before the plague broke out there; she
consequently cannot reasonably be thought to have transported the
plague, which was not in the ports from whence she came.”

To this Dr. Russel answers, that on commercial accounts the Turks
carefully conceal the appearance of the plague from the Europeans.
Should reports of accidents get abroad, they are variously and
contradictorily represented, and pestilential marks and tumours
fraudulently concealed. Though Chataud obtained a clean patent, the
plague broke out soon after his departure, and three vessels with foul
patents arrived at Marseilles a few days after Chataud. “To this (says
Dr. Russel) it may be further added, that, notwithstanding his clean
patent, persons acquainted with the Levant will think it far from
improbable, that the plague might actually have been in Sidon when
he sailed, though unknown to the magistrate, by whom the patents are
granted.... A clean bill of health imports that the place has been free
from plague, and all suspicion of plague, for a certain space of time;
but the clean patents of the two first arriving from the Levant, after
the cessation of the plague, are, according to Mr. Howard, deemed foul
at Marseilles, and the passengers are obliged to perform a quarantine
of thirty-one days. The French consuls lying under an obligation to
insert in their patents a detail of circumstances, it must appear
strange, when the condition of Syria at that time is considered, how
Captain Chataud should have obtained a clean patent.”

Though this must certainly be deemed a sufficient answer to the
objection, Dr. Russel goes on to give an account of what had happened
the preceding year, when the plague had raged violently at Aleppo; and
shows that, from the condition of the whole coast of Syria, a return
of the plague was certainly to be expected; that the French consuls
could not be ignorant of this, neither could the council of health
at Marseilles be unacquainted with what had happened at Aleppo the
preceding year. “The facility with which the patents seem to have been
issued in Turky, and the partial indulgence of the council to Chataud’s
ship, notwithstanding the very extraordinary mortality which had
avowedly happened on the voyage, together with their easy confidence
afterwards in the reports of the surgeon of the lazaretto, can only
be accounted for from the prevailing influence of private commercial
interest over a sense of official duty.”

Our author next proceeds to take notice of what happened during this
ship’s voyage to Marseilles. On the 31st of January he left the coast
of Syria with a clean patent, before the plague broke out. On the
25th of May he arrived at Marseilles, from Sidon, Tripoli and Cyprus.
On the voyage, or at Leghorn, he lost six of the crew; but, by the
certificates of the physicians of health at Leghorn, these died only
_of malignant fevers caused by unwholesome provisions_. These last
words in the Traite de la Peste are said to have been interpolated at
Marseilles. At any rate, as Dr. Russel observes, they could relate only
to those who died at Leghorn, not to the others, whom the physicians
had not seen.

The other account is much less favourable. According to it, Chataud
“left Sidon the 31st of January with a clean patent. The plague
discovered itself there a few days after his departure. Having
sustained some damage by bad weather, he put into Tripoli, where he
embarked some merchandise; he took in also some Turks, passengers
for Cyprus, together with their luggage. Soon after the ship had
left Tripoli, one of these passengers fell sick and died. Two of the
sailors employed to throw the corpse overboard desisted at the desire
of the pilot, and the rest of the ceremony was performed by the other
Mahommedan passengers; the ropes with which the body was lowered down,
being by way of precaution thrown into the sea. Within a few days the
two sailors who had handled the corpse were taken sick and died. At
Cyprus the ship put her remaining passengers on shore, and made a very
short stay. Soon after her departure from that island, a third sailor
and the surgeon died of an illness of a few days duration. The captain,
justly alarmed by these accidents, ordered the bedding and other things
used by the deceased to be thrown into the sea; and kept himself
carefully separate from the crew during the remainder of his voyage.
Some time after this three more sailors fell sick, and, there being no
surgeon on board, the vessel put into Leghorn, where the three sick
men died, and the physician and surgeon of the lazaretto declared the
disease to be a malignant pestilential fever.”

Our author considers the above account as a full proof of the plague
being imported by Chataud’s vessel: he declines entering into the
question about the _possibility_ of importing contagion in merchandise.
How this _might_ take place has already been explained; and the
present instance of its having been imported is as clearly proved as
can be expected. A collateral proof, with regard to the contagion of
the small-pox, we have from Dr. Huxham. A beggar, ill of that disease,
approached a certain town in England, but was not suffered to enter,
for fear of infection. The beggar died, and the infected clothes were
burnt at some distance from the town; but the smoke being blown upon
it by the wind, the small-pox in a short time made its appearance,
beginning in that part upon which the smoke was blown. This clearly
proves that _one_ species of contagion may adhere to clothes, and is a
very strong presumption that any other may do the same. It also shows
that contagion, when once produced, is by no means easily destroyed;
and consequently that all kinds of purification, even when used with
the utmost care and diligence, are scarce sufficient to ensure safety.

It would now be superfluous to enter farther into the subject of the
plague being communicated by infected goods, did not our author quote a
work of Dr. Pye of London, in which the latter from the very _Journal_
(which has been used as containing arguments in favour of contagion)
makes inferences directly opposite. “The facts related in this journal
(says Dr. Pye) seemed to me to make so clearly against the modern
doctrine of contagion, that if this writer had not mentioned them as
undeniable instances in his favour, I should not have thought there had
been any persons here in England so dull of understanding, or so much
blinded with prejudice, as to stand in need of having these facts put
into a more obvious light: but, having this occasion, I shall consider
them more largely than otherwise I would have done, and show that the
porters, who died in the lazaretto at Marseilles, received no hurt or
infection from the goods.

“To leave no room for objection, I shall take notice, that a guard
of quarantine died on board Chataud’s ship the 12th of June; but, as
this officer was no ways concerned either in unloading or opening the
goods, he could receive no hurt from them; and besides, this must have
been fourteen or fifteen days after the goods had been carried out of
the ship into the lazaretto. Further, six of their men are said to die
at Leghorn; but the town of Leghorn was not infected from thence, which
would have been more likely if there had been any infection in the
case, than that Marseilles should be afterwards infected.

“If any infection or infectious _aura_ can be supposed to be packed
up, and brought in goods, such infection or infectious aura must
necessarily issue forth from them in greatest abundance, and with the
greatest force, at the first opening or unpacking of them; and, as
it must continue to fly off every moment, and be thereby continually
diminishing, it is likewise certain, that in a very few days the goods
must be in a great measure, if not entirely, cleared of it. Wherefore,
if the porters could have been infected from the goods at all, it must
have been at the first opening of them: but, even according to this
journal, the porters that first fell sick were not taken ill before the
23d of June, whereas Chataud’s ship arrived the 25th of May preceding;
so that the goods of that ship, in purifying which the porter first
mentioned was employed, had been airing and purifying for twenty-six
or twenty-eight days before this accident happened; and it cannot be
conceived that after so long a time they should not have been entirely
purged of all infection or infectious aura, if any could have been
brought with them. Or if it can be supposed, which I think impossible,
that any part might still be left, it must withal be supposed so much
less than at first, as not to be capable of doing, those porters
especially, the least hurt: to suppose otherwise would be to argue
that the same man who some days before had received and borne a very
great quantity and force without any injury, could then be killed by a
quantity and force infinitely less.

According to the report of merchants, _Frenchmen are not subject to the
plague in Turky_; and it cannot be conceived that so small a quantity
of infectious air as can be packed up and brought in a bale of goods,
should destroy them in France, or in an air and climate distant and
different; when the whole atmosphere of the same infectious air is
found not to injure them in very infected places, and wherein it is
allowed to be bred and generated.”

Thus far Dr Pye.--Let us now hear Dr. Russel in answer.

“The death of the quarantine officer was mentioned in order to leave
no room for objection; but still it may be objected that he has
omitted the death of the sailor on the 27th of May, and asserted, in
contradiction to the journal, that the former six sailors died at
Leghorn. That Leghorn was more likely to be infected than Marseilles,
is a strange notion. The ship had landed no goods there, nor had any
intercourse with the shore; for the physician who visits the sick on
board, remains at a distance from the ship, in a boat, and the dead
bodies are sunk in the sea. As to the circumstance of the goods of
Chataud’s vessel being all in the lazaretto before the 12th of June,
it is a supposition to be attributed to Dr. Pye’s unacquaintance with
matters of that kind; for it is impossible a ship which arrived the
25th of May should discharge the whole of her cargo in two or three
days. The dispatch would have been miraculous, considering the ship
lay near two leagues from the lazaretto, and was unloaded, and the
boats navigated, by her own crew. It did not occur to Dr. Pye, that
some time, previous to the vessels beginning to unload, is taken up in
examination and other forms at _Pomegue_, and the council of health.
The loss of six men on the voyage was an extraordinary circumstance,
that required deliberation; and it appears that on the 29th, after the
death of the sailor on board Chataud’s vessel, the council determined
the quarantine of his cargo to be forty days, commencing from the
landing of the last bale; which was double the time usually allowed for
a ship with a clean patent. It is very probable, therefore, that the
ship did not begin to unload till after the 29th of May, and possibly
had not finished when the quarantine officer died, the 12th of June,
who must have been taken ill two or three days before.

“In regard to the time requisite for the complete evaporation of the
infectious aura, in what proportionate gradation its activity is
impaired by ventilation, and the specific quantity required to produce
effect on the human body, they are matters which I apprehend will
not readily be admitted to be clearly and certainly known. That the
first porters were not taken ill before the 23d of June, is very true;
but that the goods had been airing and purifying for twenty-six or
twenty-eight days, has been shown above to be an error. The Doctor also
makes two other suppositions equally erroneous. The first, that the
whole of the cotton contained in a number of bales is equally imbued
with infectious aura; the second, that all the bales of a ship’s cargo
are opened nearly about the same time. But, as the cotton contained in
these bales may not only have been collected from different villages at
different times, but packed up under various circumstances relative to
the materials used for embalage, and the persons employed in embaling
or steeving them; it may easily be conceived how the cargo of a ship,
coming even from a place where the plague actually rages, may be only
partially infected, or not infected at all. The warmest advocate for
contagion never contended for every bale of a ship’s cargo being
equally infectious. As to the airing of the bales, it is a laborious
and a tedious process. Where there is a considerable number, it takes
up several days to open and arrange them, goods of different kinds
must be disposed separately, accounts taken, and the cordage, &c.
laid up with care where it may be found again. The laborious part of
these operations is performed by the porters, who also transport the
goods from the water side to the enclosure where they are to be aired:
and, as the days of quarantine do not begin to be reckoned till all
the goods are landed, the porters for some days at the beginning are
sufficiently employed in receiving and arranging the cargo, that being
the business requiring the first dispatch. When these circumstances
are considered, it will appear no extravagant supposition, that some
of the last opened bales of Chataud’s cargo might still retain enough
of infectious aura to infect the porter on the 23d of June. To set
this retardment, almost unavoidable in the opening of bales, in a
still clearer light, it should be observed, that, by the regulations
at Marseilles, all suspected goods are subject to what is termed
_sereines_; that is, a certain number of bales are taken out of the
hold, and, being opened at both ends, are exposed to the air for
two, three, or six days, by way of trial, in order to see if any
signs of infection should appear among those employed in handling the
merchandise. When these have been aired, more or less, according to
circumstances, another parcel is opened and exposed to ventilation in
like manner: so that, according to the burden of the ship, there may
be several of these sereines, each of several days duration. In this
manner, independent of accidental impediments from wind and weather,
in sending the goods from the ship, it maybe supposed, were it at all
necessary to make the supposition, that the porters, not only on the
23d of June, but on the 7th and 8th of July, were infected upon opening
some new bales. As to the porter being infected by goods from another
ship, Dr. Pye thinks it impossible, because the ship had been twelve
days in port, and the goods must have been eight or nine days in airing
and purifying: had he been acquainted with the practice of the sereines
in quarantine, he would have been at no loss to make the accident agree
exactly with his notion of the infectious aura.... The plain matter of
fact, as it stands in the journal, is this, that six porters, employed
in purifying suspected merchandise from the Levant, died of the plague;
and their death was followed by that of the surgeon who attended them,
and part of his family.”

From this the reader will be able to judge how far the question
is decided in favour of the fact that the plague at Marseilles
was actually produced by imported contagion. It seems needless to
follow our author through his investigation of those facts which
his adversaries have misrepresented; for these must of course be in
his favour; every misrepresentation by a disputant being plainly an
abandonment of his cause. Indeed the argument against contagion at that
time was properly but one, and is set forth in no stronger language
now than formerly. Even as long ago as 1665 Dr. Russel quotes one
Gadbury an astrologer stating the difficulty as strongly, and giving a
solution of it as clearly, upon _his_ principles, as the best modern
theorists can do upon _theirs_. “If the pestilence, (says Mr. Gadbury)
be infectious, and really catching in itself, it must be so equally to
all persons that approach it, or that it approacheth; or else it must
be infectious to some particular persons only. If it be infectious to
all persons, or catching to all alike, then all persons, that come
into the sight or within the scent of it, must necessarily be subject
unto it. If not infectious unto all, but unto some particular persons
only, I say then it ought not to be deemed or esteemed infectious at
all, at least not any more infectious than are all other diseases,
viz. small-pox, scurvy, pleurisy, ague, gout, &c. since (though the
notion of infection be laid aside) there is not a person born into the
world that hath not at some time of his life (as his _nativity_ shall
truly show) some one disease or other. Never was any person subject to
violent diseases, as plague, &c. but had a violent _nativity_ to show
it, and _e contra_.”

The answer to this has been already given.--Let any other cause than
contagion or infection be supposed, and the difficulty remains equally
great. The probability is in favour of contagion, rather than a general
disposition of the atmosphere, because in the latter case the disease
would, contrary to experience, begin in a great many places at once;
but the plague begins in such a secret manner that we scarce know
whence it comes. Like fire, or a ferment in liquors, it diffuses itself
far and wide, and lastly, like an immense inundation, the source of
which is dried up, it seems to lose its power by extending too far,
and dies away altogether. We cannot penetrate into the causes of those
things, but, without any speculation at all, we can observe that the
disease falls upon people of a certain constitution more than others,
and this may be of use in preserving ourselves from it, as shall be
explained in the next section.

It is still necessary to say something of the infection spreading
from one person to another, and being kept off by refraining from
communication with the diseased. This indeed naturally follows from
its proceeding originally from the cotton: for as all the infected did
not touch this cotton, there can be no other cause assigned from its
spreading than by communication from one to another; and, therefore,
if such communication was cut off, we should naturally think that the
disease would not spread. But, in opposition to this, we have already
quoted Dr. Moseley giving a long list of convents infected, though
they kept themselves strictly shut up. Dr. Russel cites, in favour
of prevention by shutting up, two certificates, one by the bishop of
Marseilles, the other by the sheriff of the same place. To these he
adds the testimony of M. Langeron, who was actively employed throughout
the whole time that the plague continued, first as a commodore of the
gallies, and afterwards as governor of the town and its dependencies.
In opposition to these, however, he takes notice of two passages “in
books of acknowledged authority,” which he is at pains to answer;
the one is from the Journal already quoted, which says, “and what is
unaccountable, those who have shut themselves up most securely in their
own houses, and are the most careful to take in nothing without the
most exact precautions, are attacked there by the plague, which creeps
in no one knows how.” The other passage is taken from the _Relation
Historique_, “that, in the height of the pestilence, the infection
penetrated into places which had till then remained inaccessible; that
monasteries and houses shut up in the most exact manner were no longer
places of security.”

To the former of these our author answers, that “from the manner of
stating the case, one would think that all these religious had been
close shut up, without any communication with persons without doors;
and this was certainly intended by an author who has made remarks
upon it; but it will be found, upon looking into the beginning of the
very paragraph cited, that the greatest part of them are represented
as martyrs who had meritoriously exposed themselves. Of the twelve
different orders mentioned on this occasion, the Grand Augustines only
are said to have kept in their convent. But, supposing the Augustin
convent to have been actually shut up, and in that state infected; it
would by no means invalidate the instances brought of the preservation
of the convents, the certificates concerning which were granted
deliberately, after all was over; whereas the journal, written from day
to day, marking circumstances rapidly as they occurred, the author,
amongst various other affairs, had not always leisure or opportunity to
examine minutely into circumstances. It is in this light I am inclined
to consider the houses being infected which took in nothing without
the most exact precautions; and the rather, because I met with several
instances of the like kind at Aleppo, in the houses of the Christian
and Jewish nations: but in the sequel it generally appeared there had
been some improper communication carried on by the domestics, unknown
to the family at the time.”

“That the atmosphere, in a city so dreadfully circumstanced as
Marseilles, may become so highly tainted as to convey the plague into
houses shut up, cannot confidently be affirmed to be impossible, by
those who hold mediate contagion; and the concurrence of circumstances
at that period in Marseilles, renders it highly probable that such
accidents happened. But, in general, the pestiferous effluvia once
emitted into the air, do not appear to operate at any great distance
from their source; and M. Deidier asserts, that two monasteries
(from their situation, one near a burial ground, the other near a
pest-house) very dangerously situated, remained nevertheless untouched,
which he thinks an argument against infection being conveyed by the
air.”

From this long and contested account of the manner in which the plague
was received into Marseilles, we see how very difficult it must be to
come at a true state of facts, when a number of people think it their
interest to misrepresent or conceal them. The limits of this treatise
will not allow us to follow our author through the numerous details
of misrepresentations and unfair methods which the adversaries of the
doctrine of contagion have made use of to establish their opinion:
neither shall we enter into any discussion concerning the origin of
other plagues, as we should in them find the same opposite kinds of
evidence without such documents for distinguishing the true from the
false as Dr. Russel has produced in the case of Marseilles. A single
fact only, mentioned by Mr. Howard in his Treatise on Lazarettos, shall
be related, and which, if allowed to be _fact_, decides the question as
effectually as a thousand.

“When the plague raged at London in 1665, it was conveyed to the
remote village of Eyam near Tideswell in Derbyshire. In this place it
broke out in September 1665, and continued its ravages upwards of a
year, when two hundred and fifty of the inhabitants had died of it.
The worthy rector, Mr. Mompesson, whose name may rank with those of
Cardinal Borromeo of Milan, and the good bishop of Marseilles, at its
breaking out, resolved not to quit his parishioners, but used every
argument with his wife to quit the infected spot. She, however, refused
to forsake her husband, and is supposed to have died of the plague.
They sent away their children. Mr. Mompesson constantly employed
himself, during the dreadful visitation, in his pastoral office, and
preached to his flock in a field, where nature had formed a sort of
alcove in a rock, which place still retains the appellation of a
church. He survived, and the entries in the parish register relative to
this calamity are in his own hand writing, viz.

  In 1665, Sept.  Died  6
           Oct.        22
           Nov.         5
           Dec.         7
     1666  Jan.         3
           Feb.         5
           March        2
           April       12
           May          5
           June        20
           July        53
           Aug.        78
           Sept.       14
           Oct.        17
           Nov.         1

This plague is said to have arisen from a box of clothes sent from
London while the distemper was at its height in that city. But whether
this be admitted or not, it cannot well be supposed that in a small
village there could either be a peculiar constitution of the air,
collections of filth, immoderate heat, cold, or in short any general
cause from which a plague could be supposed to arise, that would not
have affected the country for a great way round. How then came this
insulated spot to be so violently affected, except by contagion? No
matter whether by clothes or any thing else. The very particular manner
in which the numbers who died are recorded, leaves no doubt as to the
fact of the distemper having been there; neither is it possible to
account for its rise on any other principle than contagion.

Mr. Howard, previous to his going abroad, had been furnished, by Dr.
Aikin and Dr. Jebb, with a set of queries relative to the plague, to
be put to the physicians in the different countries through which
he travelled. This commission he executed with great fidelity and
exactness. The physicians to whom he proposed them were, _Raymond_
of Marseilles, physician; _Demollins_ of do. surgeon; _Giovanelli_,
physician to the lazaretto at Leghorn; _They_, to do. at Malta;
_Morandi_, physician at Venice; _Verdoni_, at Trieste; _Jew_ physician
at Smyrna; _Fra. Luigi di Pavia_, prior to the hospital of San Antonio
at Smyrna. The questions proposed were as follow:

1. Is the infection of the plague frequently received by the French?

Though this was not asking in direct terms whether the plague is
infectious or not, all to whom it was proposed seem to have viewed
it in this light, Raymond of Marseilles only excepted, who answered
directly, “Sometimes it is.” All the rest, except Giovanelli, agreed
that it might be communicated by the touch, or by the breath. Verdoni
gave an instance of its being communicated by a flower which three
persons smelt at; two remained free, but the third sickened and died in
twenty-four hours.

2. Does the plague ever rise spontaneously?

In this Verdoni alone answered positively in favour of the spontaneous
rise of the plague. _They_ spoke ambiguously.

3. To what distance is the air infected? How far does actual contact,
wearing infected clothes, or touching other things, produce the disease?

To this question Verdoni answered in a manner seemingly inconsistent
with his former answer; allowing not only that the plague was
infectious, but that infected things might communicate the disease
after an interval of many years. All agreed that the strength of the
infection was greater or less according to circumstances; the distance
at which it could act was likewise uncertain. Raymond said that the
sick might be safely conversed with, across a barrier, at a few paces
distance; the Jew said at _two ells_ distance, provided the chamber
windows be not all shut. Giovanelli said it had been proved that the
infection did not extend beyond five geometrical paces. The touch of
infected clothes, or drawing in the breath of the sick, was looked upon
by him and Fra. Luigi to be very dangerous.

4. What are the seasons in which the plague chiefly appears; and what
is the interval between the infection and the disease?

To this it was answered by Raymond, that the two solstices are the
times in which it has least power. The others agreed that hot and
moist weather was favourable to its ravages; the spring, summer and
first month of autumn are dreaded. These circumstances, however,
must be variable in different countries. As to the time in which the
infection shows itself, the answer was various. According to _They_,
it “sometimes acts slowly, sometimes like a _stroke of lightning_.”
According to Verdoni, “the disease generally shows itself at the
instant of touch, _like an electrical shock_.” Sometimes the infection
will be communicated from a sick person to a sound one, who without any
disease may communicate it to a second, and that second to a third, in
whom alone it would become active.

The other questions, relative to the symptoms, prevention and cure of
the distemper, will be taken notice of in the course of the treatise.
In the mean time having discussed, with a prolixity almost exceeding
our bounds, such preliminaries as seemed most likely to throw some
light on the nature of the distemper, we shall now proceed to the
medical history of the plague, as we find it laid down in different
authors.

Though this distemper has most frequently been accounted a _fever_ in
the highest degree, yet, as we have already noticed, it seems to be
essentially different.[99] The testimonies there quoted are sufficient
to establish the fact; and, were it needful, many others might be
brought from authors both ancient and modern. In the plague said to
have taken place in the days of Romulus,[100] Plutarch relates, that
the people died without any sickness. To this very ancient testimony
we shall add that of Dr. Patrick Russel, who closes the account of
his first class of patients with the following paragraph: “That the
plague, under a form of all others the most destructive, exists
without its characteristic eruptions, or other external marks reckoned
pestilential, can admit of no doubt; and it is to be regretted that
mankind have so often, from the absence of these, been betrayed into
errors of fatal consequence on its first invasion; at which early
period human prudence can only be exerted in the way of defence with
any probability of success.”

  [99] See p. 102 _et seq._

  [100] P. 19, note.

The symptoms of this fatal disease were sometimes a sudden loss of
strength, confusion or weight in the head, giddiness at intervals,
oppression about the præcordia, dejection of spirits, taciturnity, an
anxious aspect, but without any symptoms of fever. In these, death
ensued within twenty-four hours; some were said to have died within a
few hours, but our author saw none of these, and is inclined to doubt
the truth of the accounts, having in several instances, where this
is said to have happened, found upon inquiry that matters had been
inaccurately stated, and that the patients had really been ill one or
two days.

In others the disorder was more perceptible. In a few hours the eyes
became muddy, the surface of the body cold, with drowsiness, lethargy,
and pain at the heart. In the progress of the distemper they frequently
lost the power of speech, the skin seldom recovered its warmth, or,
if it did, it was only by irregular flushings. The pulse sometimes
remained nearly in its natural state, but was, for the most part, low
and quick. They were “by turns delirious, confused and sensible, but
the comatose disposition was most prevalent. Towards the end they
suffered extreme inquietude. Vomiting in some occurred the first night;
in others a diarrhœa next day; both accelerating the fatal period; but
these symptoms were less frequent than in some of the other classes.
Buboes appeared only in a very few who survived the third day....
The total absence of buboes in such patients as perished suddenly I
have no doubt of, nor of their being in general very rare in others
of this class; though I suspect that the buboes might sometimes have
been concealed, where the disease ran out to the fourth or fifth day,
and for the same reason that the reports concerning the state of
the corpse were sometimes not true.... It was very rare to find
suspicious marks of infection on the bodies [of those who died within
24 hours].... Carbuncles were seldom visible till the month of May,
which was later than this form of the disease. It prevailed chiefly at
the rise of the plague in 1760, and its revival in the two succeeding
years, decreasing as the distemper spread; and though they were found
dispersed in every stage of the pestilential season, yet the number
of this class was proportionably small, compared with that of others.
Petechiæ, vibices, or broad, livid, roundish spots, occurred sometimes,
but were not common, and the two latter were seldom visible till after
death.”

This account of the most malignant form of the pestilence differs
considerably from that of Dr. Hodges, who seems to think that the
_tokens_, as he calls them, very generally were to be found on the
bodies of those who died suddenly. He mentions indeed a young man who
was suddenly seized with a violent palpitation of the heart, and thus
continued till his death, which took place in a few hours. In this case
the Doctor supposed that there might be a carbuncle broke out on the
heart. Dr. Russel has considered the description of the tokens given by
Dr. Hodges, and compared it with that of others called by Diemerbroeck
_maculæ mortis_, _spots_ or _tokens_ of _death_; and by this comparison
it appears that the former has spoken somewhat indistinctly on the
subject, confounding two different kinds of eruptions together. Dr.
Hodges, however, as we have already seen (p. 10) asserts, in his
_Loimologia_, that the tokens rise from within, and are broadest at
their bases, where he also supposes the pestilential poison chiefly to
lie. To the same purpose, in his Letter to a Person of Quality he says,
“The tokens have their original and rise from within, and afterwards
externally show themselves; which is evident, because the basis of them
is larger than their outward appearance, and the internal parts are
found very often spotted, when there is no discoloration visible on
the skin.” Dr. Russel, after quoting Diemerbroeck, makes the following
observations: “The author (Diemerbroeck) is diffuse on this subject,
and thinks it a mistaken though prevalent notion, that the maculæ
are merely superficial in the skin, proceeding from putrefaction,
ebullition, &c. in the blood or humours: on the contrary he affirms,
they arise from the internal parts, even the periosteum, broad at the
base, and tapering to their termination in the skin, being produced
by the _extinction_ and _extravasation_ of the vital spirits. Now
(says Dr. Russel) this answers exactly to one species of the tokens
described by Hodges, which therefore may be reckoned the same with the
_maculæ mortis_, and was probably the only one observed at Nimeguen,”
&c. On the same subject he quotes a book entitled _Medela Pestis_, in
which the author says that by careful dissection the _tokens_ may be
traced half-way deep in the flesh, and some, in the muscles of the
breast, have been followed by the incision knife even to the bone.
By the directions given by authority to the searchers in 1665, they
were ordered to look narrowly for these tokens, which were described
as “spots arising on the skin, chiefly about the breast and back, but
sometimes also in other parts. Their colour is something various,
sometimes more reddish, sometimes inclining a little towards a faint
blue, and sometimes a brownish mixed with blue; the red ones have often
a brownish circle about them, the brownish a reddish.”

On the subject of tokens Dr. Hodges further observes, that they
differed also in their degrees of hardness, some being easily
penetrated with a needle or penknife, while others, more callous or
horny, were penetrated with more difficulty. They so strongly resembled
warts, that they could scarce be distinguished from them; and Dr.
Hodges himself was often obliged to have recourse to a needle for
this purpose. They seemed hard to the touch, not unlike kernels under
the skin, the superfices being smooth. “When I essayed to prove some
of them (says he) I found them _almost impenetrable_.” Another very
remarkable circumstance relative to them was, that they were often
quite insensible, and this distinguished them from the carbuncle, which
is always very painful. Hodges also remarks, that a quick sensibility
in the skin was always a good sign, and those that went no farther than
the skin would sometimes slough off.

Along with these tokens we can scarce doubt that _petechiæ_ and
_vibices_ made their appearance. The former, even in the inferior
degrees of the distemper, were dangerous, the latter always fatal,
never appearing till the patient is within a few hours of death,
sometimes indeed not till death has taken place. Of the petechiæ Dr.
Russel says, that for the most part they predicted death, but not
without exception. Such as he observed were round, somewhat smaller
than a recent flea-bite. They were distinct, few in number, and
scattered irregularly about the breast and mastoid muscles. When they
did not appear till the approach of death, they were from the first
livid, or very dusky; but if they appeared early, they were of a less
deep colour, changing afterwards to livid. Hodges speaks of them as
deeper coloured than the spots of malignant fever, not fixed in any
particular spot, sometimes few, but commonly very numerous; the colour
sometimes red or purple, sometimes yellow, and sometimes livid or
black. From Gotwald, Russel quotes a description of these spots, which
he divides into four species. 1. Reddish, like flea-bites, soon growing
brown or black; appearing on all parts of the body except the face. 2.
In the form of lentils, spreading like the former all over the body;
ruddy at first, but in 24 hours growing dark or ash-coloured. 3. Large
brown spots, scattered here and there, sometimes intermixed with the
lentil kind. 4. Not unlike the measles, spreading all over the body,
rising afterwards in small blisters without any matter, vanishing about
the fifth day. Russel also takes notice of a species of petechiæ which
were very numerous, confluent, and of a dark red or dusky colour and
irregular figure. These were sometimes remarked in the interstices of
the former. Such instances occurred but rarely.

The vibices were much larger than the petechiæ. Gotwald says that
they covered the face as high as the nose, and from thence spread to
the forehead, disfiguring the patient in a frightful manner. They
did not appear till a short time before death. Often they appeared
unexpectedly, shooting up like lightning from the breast to the
face, in spots of various colours, blue, green, brown and yellow.
Diemerbroeck describes them as oblong spots of a livid or black
colour, like strokes drawn with a pen; sometimes they were larger,
the biggest resembling the strokes of a whip. Russel takes notice of
a kind of marbled appearance which took place at the height of the
disease, or a few hours before death; the colours being a faint blue,
and darkish red, both more or less obscure at times, but never bright.
It was not permanent, vanishing in one place, without leaving any
trace, and returning at short intervals. “The skin in various places
was sometimes deformed by narrow streaks of reddish purple, or livid
colour. When such took possession of the face they gave a frightful
appearance to the countenance, and frequently made such an alteration
in the features, and so completely disguised the patient, as to render
him hardly _knowable_ by his acquaintance. A streak nearly of the same
kind was sometimes observed darting from the edges of the buboes and
carbuncles. The vibices or weals were much longer and broader, and
more exactly resembled the marks left in the fleshy parts by blows or
stripes; they were found chiefly on the thighs, buttock, and back,
and made their appearance several hours before death, in some cases,
but in others not till after. Large blue or purple spots, the _maculæ
magnæ_ of authors, were sometimes observed with or without the vibices,
a little while before the patient expired, but most commonly were
discovered only on the corpse. Their figure in general was round,
sometimes irregular.”

Whether all these mortal signs appeared on such as died very suddenly
of plagues, and were by the English writers confounded under the
general name of _tokens_, cannot certainly be determined. Dr. Russel
saw none who died within the twenty-four hours, and few who died
within thirty hours, so that we cannot from him expect any particular
account of the situation of those who died suddenly. In general,
however, he says, that “in the most destructive forms of the plague,
the vital principle seems to be suddenly, as it were, extinguished, or
else enfeebled to a degree capable only for a short while to resist
the violence of the disease; in the subordinate forms, the vital and
animal functions, variously affected, are carried on in a defective,
disorderly manner, and denote more or less danger accordingly.” It
seems probable therefore that in those who are suddenly killed, the
same effects take place in a short time which are observed to take
place after a longer space in those who die gradually, buboes only
excepted, which require for their formation a longer time than is
allowed to the patient to live. Internal mortifications, or rather
eschars, are therefore to be suspected, and dissections have evinced
that this was really the case; but besides these there was an
appearance observed in the plague at Marseilles which is not taken
notice of by former physicians; viz. a preternatural enlargement of
the heart. M. Deidier on that occasion communicated an account of nine
dissections, but of these only one had died without eruptions. This
was a woman of 40 years of age, who lived till the third day. In her
“the mediastinum[101] was torn towards the upper part; the pericardium
of a livid colour; the heart larger than in its natural state, by the
swelling of its ventricles; full of thick, black blood. The liver was
also very large, and of a livid colour, with a carbuncular pustule on
the side of the gall-bladder, which was filled with very black bile.”
In others who had eruptions, and who of consequence we must suppose
to have lived longer, the enlargement of the heart was still more
remarkable. In one who lived eleven days, the heart was of double the
bigness, having scarce any blood in the ventricles, whose cavities
were filled each with a large polypus, that on the right side having
dilated the auricle to the breadth of four inches. The liver also
was larger than ordinary, and the gall-bladder full of a black and
green bile. The appearances were much the same in all the rest, but,
as the time they sustained the disease is not mentioned, we cannot
determine whether the enlargement of the heart took place at the very
first, or was only an adventitious symptom after the fever had come on.
Dr. Russel takes notice that such patients as he attended complained
greatly of their heart. “A sense of oppression about the præcordia
(says he) which the sick were at a loss to describe, was, in one
degree or other, a constant attendant on the plague, except in very
slight cases of infection; and where it came on early, or persisted
in a high degree, was always a dangerous symptom. The sick showed how
severely they suffered by their perpetually changing their posture,
in hopes of relief; but, when asked where their pain lay, they either
answered hastily they could not tell, or, with a fixed, wild look,
exclaimed _kulbi! kulbi!_ (my heart! my heart!) This anxiety increasing
as the disease advanced, terminated at length in mortal inquietude,
the patient, for many hours, in the last stages, incessantly writhing
his body and limbs as if in agony. Though pain at the heart was often
conjoined with the symptom just mentioned, and by the sick seemingly
blended together, it appeared to be different, and to exist separately.
They often exclaimed as in the other, my heart! my heart! pointing also
towards the scrobiculum cordis, but then would add _eujani kulbi_, my
heart pains me; or _naar fi kulbi_, my heart is on fire.” This last
pain the Doctor supposes might have its seat in the upper orifice
of the stomach; the extreme anxiety may be accounted for from the
enlargement of the heart; but as neither of these symptoms took place
in such as died in a very short time, we must be apt to consider this
enlargement not as any primary and essential symptom of the disease,
but as one which takes place when the vital powers are able to oppose
for some considerable time the cause of the disease.

  [101] The Mediastinum is a membrane by which the cavity of the
  breast is longitudinally divided. The tearing of it in any disease
  seems altogether unaccountable, unless we suppose an extraordinary
  loss of cohesion to have taken place without any mortification. The
  pericardium is a membrane surrounding the heart, and in a natural
  state contains some water, condensed from vapour after death.

In his account of the origin of the plague, Dr. Russel takes notice of
the opinion that, at the communication of the infection, the sick were
sometimes sensible of having received it. This has been observed by
Dr. Lind in malignant fevers; it has also been observed in plagues,
as we have seen from Dr. Hodges, Verdoni, and others; but Russel says
he never saw any instance of this. He owns, however, that he has seen
instances of the disease quickly succeeding a panic fear of being
infested. “In cases (says he) where the disease was not discovered to
be the plague, till upon the eruption of buboes after two or three
days, I have known several persons who had, till then, without the
least suspicion, frequented the sick, struck suddenly with a panic,
and imagine themselves ill. They felt shooting pains in their groins,
confusion in the head, and a loathing. Though in some these complaints
were merely imaginary, and soon vanished, in others they proved real;
the symptoms increasing, and being followed by eruptions. In such cases
I suspected the latent infection to have been excited by terror.”

In the instance formerly quoted from Dr. Guthrie at Petersburg,
we have a notable example of this sudden seizure by a stroke. His
information was derived from the physician-general of the Russian
army. This gentleman assured him, that “he had seen men, in apparent
good health, instantaneously drop down, as if shot by a musket ball,
by the sudden action of the pestiferous miasma, and upon duty again
in 24 hours, perfectly recovered by the operation of a strong vomit.”
Whether or not these men _felt_ any stroke at the instant of their
falling we are not told: possibly it might be only a syncope very
common in the plague, which took place at the very first invasion.
Russel informs us, that “the sudden loss of strength, and disturbance
of the functions attributed to the brain and heart, are reckoned, in a
particular manner, symptoms of the plague. In their highest degree they
distinguish the most fatal forms of the disease; and, under different
modifications, adhere to all its varieties.... The early appearance of
faintness was very remarkable in the plague,” &c.

Thus we see that the plague attacks without fever in two different
modes; one, by attacking and destroying the solid parts of the body,
the other, without any disorganization of the body, attacking the
vital principle itself, or rather the blood, from which this principle
is derived, so that a temporary suspension of all the functions
ensues. The analogy between the cause of pestilence and those visible
substances called _poisons_, is very remarkable in some things, though
in others it totally fails. In the Medical Repository[102] we have a
dissertation upon this analogy by Dr. Edward Miller. He observes, that
this analogy has been generally overlooked, chiefly on account of the
invisible nature of the aerial poison, and the suddenness of death
from poisons, more frequently than from pestilential diseases. This
he accounts for from the largeness of the dose of poisons compared
with that of contagion; “but (says he) by diminishing the quantity to
an appropriate amount, these noxious substances (the poisons) may be
made to exhibit the course, duration, and nearly all the phenomena,
of what is called a malignant fever. But, above all, the attention
of physicians has been diverted from this analogy between miasmata
and poisons, by the febrile part of the character which generally
belongs to pestilential diseases, and which, in common apprehension,
is constantly connected with them. Yet these diseases are by no means
universally accompanied with what is strictly called _fever_. There is
often a degree of virulence in the Asiatic plague, in the yellow fever,
and in all the other forms of pestilential and malignant diseases,
which altogether transcends the process of fever, and extinguishes
life in a more summary manner. In the worst cases both of poison and
pestilence, the febrile part of the symptoms excites little attention.”

  [102] Vol. ii, p. 409.

Our author does not say in what this virulence consists. In the cases
of those who die with the _tokens_ upon them, the cause is plainly
within the body; the destroying power acting with greatest efficacy
below the skin in the soft substance of the flesh. Where the patient is
suddenly seized in the manner described by Dr. Guthrie, the cause seems
to be something foreign to the body suddenly inhaled, the effects
being similar to those of fixed air when drawn in by the breath, and
of consequence easily expelled by a vigorous action of the powers of
the system. Guthrie observes, that, in such cases, it seems “as if the
contagious matter existed in a very loose state in the first passages
at the beginning of the disease.”

In the production of those _tokens_ mentioned by Dr. Hodges, we know
that there must have existed in the body a certain cause capable
of totally destroying the parts, and reducing them to an hard
eschar, similar to that produced by fire or by a caustic. As we are
unacquainted with any thing capable of producing this effect but fire,
we can attribute the origin of these tokens to nothing else but the
emission of the latent heat of both the solids and fluids which compose
these parts, and their consequent transmutation into an hard, and as
it were charred, substance. That such an emission of latent heat does
in some cases take place is evident from the production of a great
quantity of sensible heat when certain substances are mixed together.
Thus, upon mixing together oil of vitriol, oil of turpentine and strong
spirit of nitre, the whole mixture will take fire and burn violently,
though two of the ingredients, viz. oil of vitriol and spirit of nitre,
are by themselves incapable of being inflamed. In like manner if strong
spirit of nitre be poured upon oil of cloves or sassafras, the mixture
will burst out into a violent flame. Water poured upon quick lime
occasions great heat, and seems in great part to be converted into a
solid substance; for only a small part evaporates, and the slaked lime
falls into a powder to appearance perfectly dry, and from which the
moisture cannot be expelled without a very violent fire. In this case
Dr. Black is of opinion that the heat comes from the water, which,
as we have already seen, contains a great quantity of it in a latent
state. But, according to his experiments, the emission of 135 degrees
of heat is sufficient to reduce water to a state of solidity; and the
heat of lime when slaking is so much superior to this, that ships
have frequently been set on fire by it. We must therefore either say
that water in certain circumstances can part with much more than 135
degrees, or that the lime itself emits part of the heat it contains.
This last indeed seems to be the more probable supposition of the two;
for though fluids contain more heat in proportion to their bulk than
solid bodies, we have no reason to suppose that the latter contain none
at all: on the contrary the experiments formerly mentioned, especially
those made by Count Rumford, show that they are furnished with an
almost unlimited quantity.

The cause of the most violent kind of plague then we must suppose
to be something received into the body, which in a certain time,
probably sooner or later according to the strength of the contagion,
disposes to an irregular emission of its heat, which coming by a kind
of explosions, or, as Dr. Hodges calls them, _blasts_, produce those
eschars which have been called _tokens_, and seem to be no other than
partial combustions, by which the parts affected are reduced to a state
of charcoal, or nearly so.

In assigning this cause for the most deadly kind of plague, we must
naturally ask the question, how can all this take place without any
pain? for of those who died in this manner, many felt neither pain
nor uneasiness till within a few moments of death. This can only be
accounted for by the sudden and perfect destruction of the parts,
which did not allow time for any sensation of pain to take place; and
indeed in the application of caustic for an issue, the patient often
feels but little pain. It is impossible to avoid perceiving a very
strong connexion between this kind of plague and the dreadful cases of
spontaneous combustion related p. 182–186. In the case of the priest
indeed the fire seems to have come from without, though even this
cannot be ascertained beyond a doubt; but in those who were absolutely
consumed to ashes, it seems equally probable that it may have arisen
from within; and as none of the unfortunate persons seem to have made
any noise or struggle, the priest alone excepted, it seems probable
that the first attack had deprived them of all sensation, and that,
notwithstanding the terrible ideas with which such extraordinary
occurrences must have inspired those who saw them, the sufferers may
have died without feeling any pain. The priest seems to have felt
nothing after the first stroke.

Should this cause be admitted (indeed whether it is admitted or not) we
see that it is in vain to attempt to solve the phenomena of pestilence
by the doctrine of stimuli, excitement or debility. There is no degree
of stimulus, fire exepted, which can convert part of the body into
an hard eschar, neither can it be done by any degree of debility or
exhaustion. Besides, the irregular manner in which these eschars
are scattered up and down, shows that the cause has not acted from
a regular diffusion all over the body, but in a number of insulated
spots, between which the connexion can by no means be traced. In all
pestilential eruptions indeed the action of fire seems to be very
perceptible. Gotwald mentions his having observed in two patients what
he calls _papulæ ardentes_ “burning pimples,” which Dr. Russel supposes
to be a modification of carbuncular pustules. Gotwald calls them also
_fire-bladders_, and says that they were as broad as a shilling, of an
irregular shape, and the skin seemed as if _shrivelled with fire_. The
carbuncle itself approaches much to the nature of the eschar, and is
attended with violent heat in the adjacent parts. Gotwald, who gives an
account of the plague at Dantzic, distinguishes the carbuncle into four
kinds, (to be afterwards described.) Of these he says in general, that
they all _burn_ very violently at first, &c.

From all these accounts it seems plain, that in the plague there are
partial discharges of heat, from _some_ cause, upon various parts of
the body; and that, in many instances, this heat destroys the texture
of the parts entirely. When this is done instantaneosly the patient
feels no pain, but if more gradually, the pain is excessive, as in the
case of buboes and carbuncles; which the Journalist of the plague year
in London informs us were attended with such horrid pain as to make the
patients cry out in a lamentable manner. This extraordinary heat must
either come from without or within, and we have all the reason in the
world to believe that it comes from within. Mr. Hunter, in his Treatise
on the Blood, informs us that in a local inflammation there is always
an increase of heat in the inflamed part. Should this heat arise, as
it probably does, from an emission of part of the latent heat, we may
conclude, that such a quantity might be emitted, as entirely to change
the texture of the parts. Thus mortifications or destructions of those
parts may ensue, of all kinds, from the mild _pus_ to the pestilential
eschar.

In the effects of pestilential contagion we observe, if not a
_superiority_, at least a _different mode of action_ from what takes
place in poisons. All these seem to act by dissolving the blood, or
infecting it in such a manner that it supplies no sufficient quantity
of animal spirits; of consequence, the creature soon faints and
dies. In the plague, the blood does not appear to be much affected,
nevertheless it emits, in various places, certain explosions which
convert the parts into an eschar. Poisons always seem to produce the
petechiæ or purple spots which sometimes appear in the plague. In
Dr. Miller’s Treatise, already quoted, we find, among the symptoms
occasioned by arsenic, “red or dark spots appearing on the skin, and
rapid putrefaction, which renders speedy interment necessary.” Herein
it differs from the plague, for the bodies of such as die of that
distemper are not more liable to speedy putrefaction than others. Of
the vegetable poisons he also observes, that, “after death, sometimes
before, livid spots are observed on the body, the appearance of the
blood is dark and dissolved, and putrefaction speedily takes place.”
Of animal poisons--“The bite of the poisonous serpents is generally
followed by tumour, and livid colour of the part bitten, extravasation
of dark coloured blood into the adjacent cellular membrane, nausea
and vomiting, sudden prostration of strength, paralysis of the limbs,
convulsions, yellowness of the skin, hæmorrhages, &c. Livid appearances
of the body, a dark coloured and dissolved state of the blood, and a
rapid putrefaction, are observed after death.”

From all these accounts, however, it is plain, that, whatever may be
the analogy between the action of poisons and malignant fevers, they do
not in any manner operate like the contagion of the true pestilence. Of
this the constant effect is to produce buboes, carbuncles, and other
eruptions, resembling much more the effects of fire than any thing
else; or, if the patient is cut off without the appearance of these,
similar effects are observed on the internal and vital parts. Dr.
Miller’s conclusion seems therefore liable to exception; in which he
says, “that only the lighter cases of pestilence are unlike the effects
of poison, but that, in proportion to the degree of malignity, the
resemblance grows stronger.” It doth not appear that any poison hath
produced one of the characteristic symptoms of the true plague, or any
thing but what is common to animals dying of various diseases, the red
spots on the skin only excepted.

In the eighth volume of the Philosophical Transactions abridged by
Martyn, we have an account of a number of experiments by M. Deidier
and others, made upon dogs into whose veins he injected, or poured
into wounds made in the miserable animals, the bile of people dead
of the plague at Marseilles. “The consequence was, that they became
melancholy, drowsy, and without caring to eat. All of them died in
three or four days, with the essential marks of the true plague,
declared by buboes, carbuncles, and gangrenous inflammations in the
viscera, in the same manner as in the human carcases from whence the
bile was taken.”

The poisonous bile affected the creatures differently according to the
vicinity of the place of injection to the heart. In the jugular vein it
killed them in twenty-four hours, injected in the quantity of a drachm
to two ounces of water. In this short time were brought on gangrenous
inflammations, the heart was stuffed with _thick and black_ blood, the
liver was swelled, and the gall-bladder full of green bile. This shows
a very essential difference between the action of the pestilential
poison and that of others; the former, in some parts of the body at
least, coagulates the blood; the latter, in all parts, dissolves it.

In the crural vein (the vein of the leg) the effects were less violent.
In about an hour they became heavy. In the former case they instantly
became drowsy. In the second experiment they contracted such a loathing
for food, that they would neither eat nor drink any thing after the
injection was made. On the third day there appeared considerable
tumours under the _axilla_ (the fore leg I suppose) and on their
thighs, about three inches from the wound. The wound itself turned to a
gangrene, and the creatures died usually on the fourth day.

In another experiment the animal had convulsive motions all over
immediately after the injection, followed by a lethargy. Next day a
carbuncle appeared on the great pectoral muscle on the right side.
On the third, a bubo appeared on the thigh, and the same day the dog
died. From the time of the injection he had neither eat nor drank. On
dissection the fore part of the breast under the teguments was found
entirely gangrened, the inward parts and viscera full of black clotted
blood, the outward surface of the lungs was all purple, the heart was
swelled as big again as usual, and the four cavities were full of black
clotted blood. The bile of this dog, injected into the crural vein of
another, produced similar symptoms, only the latter eat a little boiled
meat, which he vomited up again in two hours. He died the third day,
with the same symptoms of the plague as the others.

The bile of people who died of ordinary malignant fevers was much less
powerful. A quantity (not mentioned how much, but probably a drachm)
mixed with four ounces of warm water, was partly injected into the
jugular vein of a dog, and a compress soaked in the rest of the liquor
applied to the wound. He appeared heavy and sleepy, and would neither
eat nor drink till the third day, when he did both willingly. On the
fourth day the compress fell off, the wound was found to be diminished
one half, and healed by degrees, the dog recovering perfectly. In
another experiment with the bile of a patient who had died of a
malignant fever, the dog not only had about a drachm of it put into a
wound in his thigh, but was made to swallow some of it; notwithstanding
which he was not seized with any distemper, and the wound healed in
fifteen days. This bile was as black as ink, in great quantity, and
very thick. In the other subjects it was of a deep green. In another
experiment, with the same bile applied on a compress, the dog likewise
escaped without any apparent disorder; but in a third, the animal died
in twenty-three hours, though at first he had shown no sign of being
affected, only that he seemed to be thirsty, and drank with greediness.
On opening him his heart was found still to beat with violence, and,
after the beating ceased, no blood was to be found in it, either in
the auricles or ventricles. “This liquor, crowded together in the
great vessels, appeared of a lively red, and very fluid, without any
of those concretions that we constantly observed in those who died of
the plague. Here appeared neither external nor internal marks of the
plague.” The bile of a person who had died of an erysipelas, injected
into the crural vein of a dog, produced no bad effect. A dog was killed
by half a drachm of Hungarian or blue vitriol injected into the jugular
vein. He died in universal convulsions: the heart was full of grumous
blood, reduced to a kind of thick pap, but without any clots. The bile,
applied to two wounds in another dog, produced no bad effect.

From other experiments it appeared that even the pestilential poison
itself, taken into the stomach of dogs, did not produce any deleterious
effects. “A dog of the Hospital of the _Mail_ in Marseilles, who
followed the surgeons when they went to dress the sick, used greedily
to swallow the corrupted glands, and the dressings charged with pus
which they used to take off the plague sores: he licked up the blood
that he found spilt on the ground in the infirmary; and this he did
for three months, being always gay, brisk, well, full of play, and
familiar with all comers.” The health and briskness of this unfortunate
dog proved his ruin, by making him the subject of philosophical
experiment. A drachm of the pestiferous bile injected into the crural
vein, killed him in four days. He had a considerable hæmorrhage from
the wound the night before he died, and he had also a disagreeable
smell both while living and after he was dead. Two other dogs, which
had swallowed a quantity of pestiferous bile, became heavy and
melancholy, refused their food, and showed other signs of disorder;
but all these went off in a short time, and no signs of the distemper
appeared.

These experiments induced M. Deidier to suppose that the contagion of
the plague lay only in the bile; but the following experiment shows
that the blood was equally infected, and capable of communicating the
disease, and that of the most malignant species. It was made by M.
Couzier, physician to the infirmary at Alais, and in the Philosophical
Transactions we have the following account: “I took a quantity of blood
from a person dead of the plague, and mixed it with warm water, which
mixture I attempted to inject into the crural vein of a dog, but the
end of the syringe being too large to enter the vein, the experiment
did not succeed. This made me resolve to try to lay some of the same
infected blood upon the wound. This I accordingly did, and covered it
with a dressing, which the dog got off in the night. I found the next
morning that the dog had licked the wound, and that he refused his
food. Towards night he began to bemoan himself, and gave signs of an
approaching death. The next morning I found him dead, the wound being
considerably swelled and gangrened, and the edges round the swelling
were likewise gangrened.

“Upon opening the body, we found the liver something larger than usual,
with spots of a livid purple, as in the bodies of persons dead of
the plague. In the stomach was found a quantity of black coagulated
blood, of the size of a hen’s egg. This in all likelihood was what he
had swallowed upon licking the wound. The heart was very large, with
a black grumous blood in the ventricles, and the auricles were turned
blackish and gangrenous.”

This last experiment naturally brings to remembrance those of Dr.
Home at Edinburgh, in which he inoculated the measles by means of
the blood of patients ill of that disorder. From the accounts he has
given in his treatise entitled Medical Facts and Observations, we can
have little doubt that _his_ experiments succeeded, however others
may have failed. One thing, however, is very obvious, viz. that if we
mean to communicate a disease by means of the blood, we must use a
much greater quantity than if we make the experiment with the matter
of an abscess. The case of contagious diseases seems to be the same as
in fermenting liquors. With a small quantity of yeast we can easily
induce fermentation in any proper liquor, but, if we skim off the
yeast, and use only the pure fermenting liquor, we must use a much
greater quantity; and to inattention to this circumstance we may with
probability ascribe the difficulty which Dr. Home himself met with in
introducing the disease, and the total want of success in others. In M.
Couzier’s experiment a considerable quantity must have been used, as he
says that in the dog’s stomach it equalled the size of an hen’s egg. A
much smaller quantity of matter taken from a pestilential abscess is
capable of producing the disease in a human body, as is evident from
the case formerly quoted of that gentleman who inoculated himself for
the plague, and of which Dr. Guthrie gives the following account: “This
was Mathias Degio, one of the surgeons of the hospital at Bucharest, a
building appropriated to the cure of the plague in the Russian army.
He, perceiving the gentlemen of his profession _condemned in a manner
to death, if punctual in the discharge of their duty_[103] had the
resolution to inoculate himself for the plague, in the full confidence
of its efficacy, and ever afterwards found himself invulnerable, whilst
his companions around him were falling victims to its fury. He produced
the disease by inserting, with the point of a lancet, under the
epidermis of his arm, matter from a pestiferous abscess, and followed
the cold regimen observed in the small-pox, as he had imitated its
mode of inoculation. On the fourth day of the puncture the fever
declared itself, and he, being perfectly devoid of fear, got through
the disease without feeling more inconvenience than if it had been that
which he imitated. He drank freely of cold water, with vinegar, or a
little wine, and kept generally out of doors. This beverage was the
only thing that had the appearance of medicine,” &c.

  [103] This, among innumerable other instances that might be brought,
  is a proof of the infectious nature of the plague.

From a careful attention to all these histories, it is plain that the
plague is naturally an eruptive disease, as, in all the animals in
which it was artificially brought on, eruptions took place, provided
the life of the creature was sufficiently prolonged to allow them to
come out. Dr. Russel says, that, from his diary, he noted down the
cases of _two thousand seven hundred_ patients, _all_ of whom had
eruptions of one kind or other. In this it agrees with the small-pox,
which Dr. Mead justly considers as an inferior kind of plague. In the
latter, however, the eruptions seem to resemble those called by Dr.
Hodges the _tokens_, only that the cause which produces them is less
violent in its nature; but why the eruptions of the small-pox should be
in distinct pustules, and not one continued boil all over the body, is
undoubtedly inexplicable on any theory whatever. The same is true of
the plague. No man can explain why the tokens, for instance, instead
of being collected into one great eschar, are dispersed into small
distinct pieces; or why, instead of buboes in the groin and armpit, or
instead of carbuncles in different parts of the body, there should not
be a single one equivalent in bulk and power to them all. This appears
similar to the phenomena of rain, hail or snow, which fall in distinct
drops, fluid or congealed, or in flakes, instead of being equally
diffused all over the spot on which they fall. In the latter case we
say that the phenomenon is occasioned by _electricity_: we may say the
same, if we please, of the small-pox and plague, with equal emolument.

From the accounts we have just now quoted, it appears that there is
between malignant fevers and the true pestilence a very essential
difference; the latter tending to thicken the blood, the former to make
it thinner. In this respect therefore the poisons seem to resemble
malignant fevers very considerably; for M. Fontana observed that by
mixing animal poisons with blood drawn from a vein, it was prevented
from coagulating. In the instance above related where a dog died in
consequence of bile injected into his veins from one who died of a
malignant fever, the blood was found extremely fluid. In some who died
of the hospital fever, Sir John Pringle informs us, that suppurations
had taken place in the brain; but in the true plague the tendency to
mortification always prevailed above every thing.

Lastly, that the plague proceeds from too great a quantity of heat,
either emitted from the body itself, or some how introduced into it,
seems to be pretty plain from the effect it has of augmenting the
venereal appetite to an almost inconceivable degree. This was taken
notice of in the plague of Marseilles, and indeed in many others.
Russel quotes two remarkable passages to this purpose; one in a plague
at Genoa, the other in Messina. “Amidst so many dreadful fears and
terrors, amid so many fetid and putrefying bodies, amid the shrieks,
the sighs and the groans of the sick, what would you have expected?
That the people, struck with dread and horror, remained sad, modest
and quiet. You are mistaken. They sung, played on instruments, danced,
intrigued, and Genoa never was seen so shameless, debauched, and
disorderly. I have said before, that God in this plague gathered in
a harvest for heaven; but it seemed to be also a vintage for the
lascivious of of the earth. If not so, how came so many marriages
to be celebrated in the Lazaretto of Consolation, and that so many
women, without shedding a tear for the death of their husbands,
immediately entered into new engagements? One day, in particular, five
marriages were performed, four of the bridegrooms being buriers of the
dead, and dressing themselves and their brides in clothes stripped
off from the bodies of the deceased.” On the plague of Medina he
quotes the following extract of a letter written by a gentleman who
resided in that city during the plague in 1743. “It has always been
observed, that, after _every_ plague, those who recover are addicted
in an extraordinary degree to lewdness and incontinence, which was
surprisingly visible at Messina, and carried to such a degree of frenzy
and bestiality, that many were known to violate the bodies of dead
virgins!”

That an extraordinary propensity to venery may be produced by
introducing into the body a quantity of heat, admits now of a kind
of demonstration from a fact mentioned by M. le Roy concerning
phosphorus.[104] This substance is exceedingly apt to take fire on the
application of a small degree of heat, and even by slight friction. It
is now introduced into the materia medica, and is found to be a very
powerful medicine, though dangerous on account of its inflammability,
the heat and air contained in the human stomach being sometimes
sufficient to set it on fire. The taking such a substance into the
body therefore seems not much different from taking actual fire into
it; and indeed M. le Roy mentions the case of a woman who had taken
only a single grain, and who he says had been recovered, _by it_, from
a putrid fever, but died suddenly from some imprudence. In this woman
the whole substance of the body was found luminous upon dissection, and
the hands of the operator continued luminous even after being washed.
M. le Roy, having taken three grains of this fiery substance, found
himself extremely incommoded by it for some hours, and was obliged
to drink great quantities of very cold water. Next day he found his
muscular powers amazingly increased, and had an _almost insupportable
venereal irritation_. This we see was the consequence of throwing into
the body a quantity of heat from without; but if the body itself emits
that heat which it invisibly contains, the effects must be the same as
though an extraneous quantity had been thrown into it. Neither are we
to imagine that the _quantity_ of heat contained in our bodies is small
or inconsiderable; for we have already seen that heat consists in the
efflux from any substance, of an invisible and most subtile fluid, in
all directions. When this flux is gentle, the heat is moderate, but in
proportion to the activity of the discharge, the temperature becomes
hotter and hotter, and if very violent, the cohesion of the parts is
dissolved entirely, and the substance is said to be on fire. There is
required therefore only some cause to begin the emission of this fluid;
for as soon as this begins, the immense quantity with which we are
surrounded, will supply more in abundance,[105] and continue so to do,
as long as the original cause subsists, or until the substance can no
longer bear the power which operates upon it.

  [104] Memoires de Societe Medicale, &c.

  [105] If we consider the composition of the atmosphere which
  surrounds us, we must acknowledge that by far the greater part of
  it consists of fire and electric fluid, the latter being properly
  the element in a comparatively quiescent state. In deflagrating
  dephlogisticated and inflammable air, the mixture has sometimes
  shrunk up into a three hundredth part of its bulk; which shows that
  of these airs two hundred and ninety-nine parts are fire, the single
  remaining part only being earth, water, or some solid matter which we
  call the _basis_ of air.

From this view of the causes of the plague, and from the facts which
have been laid down concerning it, we cannot help perceiving a very
strong similarity between the plagues mentioned in the Old Testament
and those which still exist in the world. In one of the passages
formerly quoted it is called an _inflammation_, an _extreme burning_;
and from the testimonies of different authors above quoted, it is plain
that the disease still deserves the name bestowed upon it in the sacred
writings. From the account given of its proximate cause, it is plain
that plagues of all degrees of intensity may take place, from absolute
accension of the body, and its reduction to ashes, to the mildest
state of the disease, in which the patient is not confined to his bed;
and all this from the single principle of emission of heat from the
body itself. It likewise appears that there may be either in the body
itself, or in the element which surrounds it, such a constitution as
will dispose that element which is the natural and immediate preserver
of our life, suddenly to attack and destroy it, of which the case of
the Italian priest is a most remarkable instance. In other cases, such
as the Italian lady, and the woman at Coventry, the body itself seems
to have given out its heat, though this could not be done without a
concurrence of the surrounding ethereal fluid. In a stage still lower,
the body is partially consumed, or rather partly charred into a kind
of cinder, as where the _tokens_ are produced; and when the cause acts
with still less violence, a fever is produced. In the Old Testament
we find these different kinds of plagues very distinctly mentioned.
In some cases the offenders died by actual fire, which either struck
them from without, or was kindled within their bodies. In others, they
seem to have died by that very deadly kind of plague of which we have
already said so much, which kills in a few hours. This was probably the
plague which destroyed the army of Sennacherib, and this in the tenth
chapter of Isaiah is by some thought to have been prophesied of under
the title of a _burning like the burning of a fire_.

Of these things I the rather take notice, as I perceive, in a late
oration, not only the doctrine of the plague being propagated by
contagion severely ridiculed, but the scripture itself treated in a
most indecent and scandalous manner. “In the earliest ages of the world
(says he) when ignorance and superstition led men to attribute all
extraordinary phenomena to the direct agency of supernatural beings,
pestilence was supposed to be immediately imported from heaven. This is
the opinion which appears to have prevailed among the ancient Hebrews,
and may be ranked at the head of the catalogue of absurdities on this
subject. The dominion of prejudice over the minds of that ignorant and
obstinate people appears in this instance particularly striking. Such
was the depth of their blind bigotry in favour of the healthfulness of
the globe they inhabited, that they would seem to have considered it
as even superior to that of the celestial regions. Hence, unwilling
to believe that their favourite earth could give origin to an evil so
dreadful as the pestilence, they imported the seeds of this calamity
from the more unhealthful climate of heaven!!”

In this extraordinary paragraph we find the matter so much
misrepresented, that every vestige of truth is swallowed up in it.
The Hebrews believed that they were under the immediate inspection
and government of the Deity; a doctrine which, however our author
may _disbelieve_, he cannot _disprove_. But, notwithstanding this
immediate inspection and government, the Deity never did bring upon
them any plague but by the intervention of natural causes. The agents
which he had originally created were sufficiently able to execute
his purposes. The Creator never employed any power but what already
existed in the world, and the power that he generally did employ was
_fire_. This agent he directed to exert its force in such degrees as
he pleased, and against whom he pleased. It is a mistake to think that
miracles were _immediately_ the effects of supernatural power. They
were all accomplished by the very powers which exist in the world at
this moment, only these powers were by the Creator at particular times
directed to act in a manner that they would not have done had they
been left to the mechanism of their own nature. When we read therefore
of people being consumed by fire from the Lord, there was neither
importation of fire from heaven nor any where else; the element exerted
its power on these particular persons, either by lightning proceeding
from the cloud which represented the Deity, or their bodies threw out
the latent heat which they contained, and consumed of themselves. That
in cases of this kind there was no _importation_ supposed, is evident
from an expression used about bringing water from the rock. It is not
said that the water fell from the stars, or came down with the tail
of a comet, but that the rock gave out the water which it previously
contained. At the present day the same powers exist, and sometimes
produce the same effects that they did in former times, with this
difference, that now, having no intelligent agent to interfere with
their natural mode of action, they exert their force indiscriminately,
and as the mechanism of their nature happens to be stimulated, they
destroy every thing promiscuously before them. In all this I cannot
perceive the smallest absurdity, or any thing but what a reasonable
man _may_ indeed _must_ believe, if he makes use of his reason. As to
the causes which Dr. Caldwell so much insists upon, viz. filth and
corruption, it is extremely probable that (while the Israelites were in
the wilderness) these had no existence. By their law they were enjoined
such frequent ablutions, that their bodies must always have been
perfectly clean. Human excrements were not allowed to lie above ground.
The offals and dung of their sacrifices were carried to a distance, and
they were expressly told, that they must not allow of any uncleanness
in their camp, lest God should turn away from them and abhor them. Add
to all this the great heat and dryness of the desert in which they
wandered, which would quickly parch up and carry off the moisture from
any dead carcases or putrefying matters that might be allowed to remain
notwithstanding the injunctions to the contrary. Indeed if we consider
the dryness of the climate where these people were, and that they were
constantly attended by a large stream of water, it is difficult to
conceive any situation upon earth more healthy than that of the Jews in
the wilderness. If plagues therefore came upon them, it is difficult
to say how they could have happened according to the ordinary course
of nature; and, if not according to this, it must have been by an
alteration of it, or by miracle.

The plague, as has already mentioned, in its very severe state appears
most commonly in the beginning of an epidemic season, and is neither
very common nor very infectious. The most common mode in which it
invades the patient is with the symptoms of a malignant fever; and
of cases of this kind Dr. Russel has made up his five classes of
patients, the first or deadly kind having been already described.
In his second class, the next in malignity to the fatal kind, the
disease made its attack with a slight shivering, succeeded by fever
with giddiness, vomiting, head-ach, and sometimes looseness. In the
night the fever increased, the thirst was excessive, and the patient,
harassed by the vomiting, &c. passed a very unquiet night, frequently
with delirium or coma. Towards morning the fever abated, the sick
recovered their senses if delirium had taken place, but if coma, it
continued through the day, and the remissions were less. Throughout
the first day, and part of the second, the pulse was full and strong,
but on the second it began to alter, and some of the characteristic
signs of the disease to appear. The principal of these was a certain
muddiness in the eyes, which sometimes took place even on the first
day. This is by our author accounted a symptom very difficult to be
described, and, though he recounts the descriptions given by several
authors, none are found adequate to the real appearance. “It resembled
(says he) somewhat the dull, fixed eye observable in the last stage of
malignant fevers; but the dullness was different, muddiness and lustre
being strangely blended together. It continued with little alteration
in the remissions, and even where the patient appeared sensible and
composed it did not increase in the febrile exacerbations, but the
eyes acquired a redness that added wildness to the look, which abating
or going off in the remissions, the muddiness remained behind. It
was this which contributed chiefly in composing that confusion of
countenance which I shall not attempt to describe, but which enabled me
to pronounce with tolerable certainty whether the disease was or was
not the plague, though not independently of other symptoms. When this
muddiness disappeared or abated, it was constantly a favourable sign.
After a critical sign it often disappeared suddenly, but where there
was a succession of sweats, or where no visible crisis happened, its
disappearance was slow and gradual.”

Along with this muddiness the patient had a peculiar confusion of
countenance; the pulse quick and equal, or low and fluttering, but
rarely intermittent; the external heat moderately feverish, at other
times intense, with irregular flushings, with pain at the heart,
or oppressions about the præcordia; burning pain at the pit of the
stomach, and incessant inquietude. When to these symptoms were added a
faltering in the tongue, loss of speech, while the surface of the body
became cold and damp with clammy sweat, death was inevitable. In the
evening of the second day all the symptoms became worse; and in the
morning the patient appeared to lie quiet more from his strength being
exhausted than from any change to the better. When the vomiting had
ceased, however, there was frequently such a remission on the third day
as gave the attendants great hopes of a favourable event; but these
hopes were always fallacious and of short duration. Sometimes where
vomiting, looseness or hæmorrhage had preceded, the patient died on
the third day: at any rate, none of this class recovered, whether the
disease was left to itself, or treated with medicine. The appearance
of buboes was of no consequence, for they never came to maturity, and
the little advances they made neither accelerated nor retarded the
termination of the disease, which happened sometimes on the third, but
more frequently on the fifth or sixth day.

The third class of patients were equally unfortunate with the other
two. “The difference between the second and third consisted in the
absence of vomiting at the beginning, the later accession of coma
and other bad symptoms, and a slight tendency to perspiration, which
very rarely occurred in the second.... From the second or third night
the course of symptoms in both classes varied very little, and the
termination of the disease was in both the same: it may be added they
reigned together through all the periods of the pestilential season,
but were most prevalent in its augment; for at its height, and in its
decline, they gave place to varieties of the disease less destructive.”

The fourth class was the most numerous of all. Its distinctive marks
were, “the continuance of the inflammatory or febrile symptoms with
less interruption than in the other, a pulse more constantly sustained,
or soon recovering itself when hurried in the exacerbations; the
length and vigour of the exacerbations decreasing in the advance of
the disease; and, above all, the prevalent tendency to a favourable
discharge by the skin, with the critical sweats on the 3d, 5th, or
subsequent days.... Vomiting was a concomitant in about one fourth of
the sick. The fever, for the most part, was very moderate the first
night, very rarely accompanied with delirium, and almost never with the
comatous disposition.... The buboes and carbuncles commonly made their
appearance the first day; but it was not unusual to see a successive
eruption of these in the course of the disease.... The morning sweat,
on the third day, in some cases proved completely critical, but more
commonly produced only a remission so favourable as to encourage the
expectation of a more favourable crisis on the fifth; but, where the
patient neither sweat on the third, nor a sensible remission took place
on that day, some degree of danger was always to be apprehended....
After the sweat on the fifth, the subsequent exacerbations proved
slighter and slighter, and the buboes for the most part advancing
favourably, little or no fever was left remaining after the beginning
of the second week, except perhaps symptomatic heats occasioned by the
eruptions.” In this class the patients sometimes appeared only to have
a slight attack, and yet at last were seized with mortal symptoms,
while others who deemed to be much worse at first yet happily recovered
and did well, In general the severe pestilential symptoms did not come
on till a considerable time after the attack.

To the fifth class our author refers all cases of slight infection,
wherein the more formidable symptoms of pestilence never concurred,
and _all_ the infected recovered. “The access here was often attended
with so little apparent disorder, that the eruptions gave the first
alarm; and the fever which came on afterwards was frequently so slight
as not to confine the sick to the house. Others found themselves
indisposed for two or three days, but were not sensible of any
febrile heat whatever. But in this class the disease did not always
invade thus insensibly. The febrile symptoms, especially the first
three days, sometimes run pretty high; and the fever afterward, in
nocturnal exacerbations particularly, run out to the end of the week
or longer: but, as there was no concurrence of alarming symptoms, and
the exacerbations, terminating for the most part in sweats, gradually
diminished in force after the third or fourth night, it was not
difficult in the worst cases to foretel the event at that period, nor
necessary in others to defer the decision so long.

“_All_ the infected had buboes or carbuncles, and very often both
eruptions concurred in the same subject. Persons not confined
by indisposition were often, by the inguinal buboes, prevented
from walking abroad. The carbuncles constantly formed the _black
crust_,[106] and then suppurated; the buboes in one third of the sick
dispersed. The dispersion of the buboes was never observed to be
attended with bad consequences, notwithstanding the general neglect of
purging in the decline of the disease: indeed very few had recourse
to remedies, topical applications excepted, unless perhaps a bleeding
at the beginning, where the febrile symptoms ran high. This class was
_nearly as numerous_ as the fourth, but began to predominate rather
later, and reigned most of all in the decline of the plague in 1762.”

  [106] This is in favour of what has already been observed, that
  the pestilential eruptions in _all_ cases showed a tendency to
  mortification.

The sixth class must be omitted, as containing dubious, anomalous
and extraordinary cases. We shall therefore proceed to consider the
accounts of the plague given by other physicians, which, without
questioning the accuracy of Dr. Patrick Russel in relating what _he_
has seen, may serve to throw some light on the subject, by relating
what _others_ have seen. Dr. Alexander Russel, in his Natural History
of Aleppo, gives the following description of it. “The distemper
in itself is the most lamentable to which mankind are liable. The
torments of heat, thirst and pain frequently unite in some patients; an
unspeakable dejection and languor in others; and even those who escape
with life do not cease to suffer from painful and putrid ulcers, the
painful remains of the disease. The desertion of relations, of friends,
and of domestic servants, the want often of the common necessaries
of life, and the difficulty of procuring medical assistance, are
circumstances likewise which aggravate the miseries of the sick, and
contribute greatly to augment the general horror.

“But, as no disease incident to mankind is in its nature more terrible
and destructive, so none is more difficult to observe. Its symptoms
are scarcely in all respects alike in any two persons, and even vary
extremely in the course of an hour in the same subject. The disease,
attended in the beginning with symptoms not highly alarming, often ends
fatally in a few hours; while the most formidable attacks, by a sudden
and unexpected alteration, sometimes terminate happily.

“The first complaints of those seized with this distemper, were,
in general, a coldness or shivering; sickness; a vomiting of large
quantities of porraceous bile, which often had a very offensive smell;
anxiety, or an inexpressible uneasiness about the pit of the stomach;
pain in the back or loins; an intense head-ach; uncommon giddiness, and
a sudden loss of strength. Some were sensible of a sharp shooting pain
darting at intervals into the parotid, axillary or inguinal glands.
To these symptoms succeeded a violent fever; in which, while the sick
complained of extreme inward heat, their skin, externally to the touch
felt little hotter than usual. Sometimes this heat became general
and intense; at other times particular parts only were affected; but
it seldom continued long in the same degree, having several unequal
remissions and exacerbations in a day. In these exacerbations the face
became florid, but would often from a deep scarlet change to a livid
colour, like that of a person almost strangled, and, again suddenly
changing, it would assume a cadaverous paleness. The eyes, soon losing
their natural lustre, acquired a kind of muddiness; and the countenance
of most of the sick was ghastly and confused beyond description. The
pulse the beginning was somewhat quicker and lower, but in other
respects varied little from the natural state. Within a few hours it
commonly increased in quickness and strength, but seldom remained
the some for an hour, nay scarcely many minutes together; incessantly
varying, both as to strength and quickness, and without any manifest
correspondence with the other febrile symptoms.

“In such as complained of pains darting either into the parotids,
the arm-pits, or the groins, a small hard, deep-seated tumour, with
external discoloration of the skin, was discovered by the touch in the
part, and these were the incipient pestilential buboes.

“The appearances now described were those of the distemper on the
first day, till evening, when the sick always suffered a severe
exacerbation, in which the heat both internal and external became
excessive; and, as they generally were by that time delirious, it was
often with difficulty that they would be kept within doors; they were
greatly disposed to talk, but faltered so in their speech, that what
they said was hardly intelligible, the tongue having shared with the
other organs in the general debility. The exacerbation lasted the
most part of the night; but the heat, delirium, and inquietude abated
towards morning, and a manifest remission took place. Some recovered
their senses entirely, some partially, and then complained of intense
head-ach, or of pains from the buboes; it was usual in this interval
also that those who had carbuncles began to complain of _burning_ pain
in those _fiery_ eruptions. The morning remission was commonly of very
short duration; the rigours, anxiety and delirium soon returning more
violent than before, attended with a strong and frequent subsultus
tendinum. These febrile symptoms did not increase regularly as the day
advanced; but went away and returned at intervals leaving short but
alarming intermissions; for each exacerbation surpassed that which
preceded it either in violence or duration. In the evening the pulse
could hardly be counted, by reason of its depression and quickness; the
patient became comatose, and the respiration was quick, laborious, and
interrupted. The buboes which, some hours before, seemed manifestly to
advance, often subsided, and sometimes almost entirely disappeared;
the carbuncles, mortifying at the top, resembled a _great eschar made
by a caustic_: and at this period also livid or black spots, of various
dimensions, often were found scattered universally on the body.

“Under these circumstances, dreadful as they seemed, some hope of
recovery still remained; for, though many of the sick died on the third
day, several had a favourable crisis on that day, by a profuse sweat;
some struggled to the fifth day, a few to the seventh, and, here and
there one, even to the eleventh; before any critical alteration took
place. Where a copious sweat happened on the third day, if it did not
prove perfectly critical, it at least always considerably abated the
fever; which, in that case, was generally totally removed by a second,
though less profuse sweat, on the fifth: and then besides weakness the
chief remains of the disease consisted in the pain of the eruptions.

“Nothing could be predicted with respect to the event of the disease
from the manner of its invasion; those who had the most favourable
escape having been often in the beginning attacked with as alarming
symptoms as others were who died in a few hours. Sometimes the febrile
paroxysm, which had set in with such formidable violence, dissolved
in a few hours, and left the patient languid indeed, and weak in an
extreme degree, but free from other complaints except the pain arising
from the bubo, which from that period increasing in size, and advancing
favourably to maturation, was, in many cases, ready to open in twelve
or fifteen days: the patient all the while, except the first day,
walking about as usual. Great numbers happily escaped, not only in the
manner just described, but likewise where the buboes never advanced;
for these tumours, so far from coming always to maturation in such as
recovered, very often discussed without any bad consequence. Carbuncles
often began to digest before the termination of the fever in a critical
sweat.

“All the infected had buboes, except such as expired suddenly, or
survived the first attack a few hours only. Instances of this dreadful
kind were more particularly observed in March 1743. The sick were
seized in the usual manner; but the head-ach, vomiting, and pain
about the præcordia, increasing every moment, proved suddenly mortal,
or terminated within a few hours in fatal convulsions.” Dr. Patrick
Russel observes, that such instances of sudden death were very rare in
the plague of 1760, 1761 and 1762; and in these they happened only in
the winter, or early in the spring. In such sudden deaths few had any
appearance of buboes; but in general the armpits and groins, or the
inside of the arms and thighs, became livid or black, and the rest of
the body was covered with confluent petechiæ, livid pustules being here
and there interspersed: but all these appearances were more especially
observed after death.

In the plague of 1760, vibices as well as livid and black spots were
frequently found on the corpse, but not constantly. They were always
suspicious in conjunction with other circumstances, but their absence
was no proof, though frequently urged as such, that the distemper was
not the plague. The vibices sometimes appeared several hours before
death, but the livid spots seldom or never.

The tongue in some was quite moist, and continued to be like that of
a healthy person throughout the disease; in others, white at first,
then yellow; at last black, and covered with a dry, foul scurf or fur.
The thirst was generally very great, but never constant; returning at
regular intervals, and never appearing to correspond with the danger
of the fever. Sometimes it was so little that the patient could not be
prevailed upon to drink a sufficient quantity. The appearance of the
urine was equally variable, and afforded no certain prognostic; being
seldom alike in any two patients in the same stage of the distemper,
and varying in the same patient every day. The vomiting commonly ceased
after a few hours, excepting where the sick were induced by thirst to
load their stomach, in which case it always returned. Sometimes the
patients were costive, in others a diarrhœa took place, but in most
the discharges were natural. No critical solution by urine or stool
seemed ever to take place. A few cases of hæmorrhages from the nose and
uterus were observed; and if they happened after the second day, were
soon followed by a plentiful sweat, which commonly proved critical;
“a circumstance different from what has been usually observed in the
plague at other places.

“From the preceding account of the plague it will readily be conceived
that nothing can be more difficult than to form any judgment or
prognostic of the event of the disease; in which, as it is justly
remarked by Morellus, our senses and our reason deceive us, the
aphorisms of Hippocrates are erroneous, and even Hippocrates (as I am
inclined to think) might have erred in his judgment.”

Innumerable other histories of the distemper might be given, but the
following, it is hoped, will be sufficient, along with what has been
already detailed, to show that the plague in former ages was the same
as at this day. In the terrible plague which broke out in the time of
Justinian, the distemper sometimes began with delirium, and the patient
instantly despaired of life; but more generally people were surprised
by the sudden coming on of a slight fever; so slight that no danger
was apprehended either from the state of the pulse or colour of the
body. This, however, was quickly followed, sometimes even on the same
day, sometimes on the second or third, by buboes or parotids (swellings
behind the ear) which when opened were found to contain a black _coal_,
or _eschar_, of the size of a lentil. If these swellings suppurated
kindly, the patient recovered, but if not, a mortification ensued, and
death was the consequence, commonly on the fifth day. Black pustules or
carbuncles, covering the body, were signs of immediate death, as was
likewise a vomiting of blood in weak constitutions; for this terminated
in a mortification of the bowels. Pregnant women generally perished,
but women were less susceptible of the infection than men; and young
persons were in more danger than old. Many, who recovered, lost the use
of their speech, and such were not secure from a relapse.

In the last plague at Moscow, the symptoms were various, according
to the persons, constitution and the weather; in general, head-ach,
giddiness, shivering, loss of strength, slight fever, sickness and
vomiting, redness of the eyes, white and foul tongue, with a dejected
countenance, buboes and carbuncles appearing on the second or third
day, but seldom on the fourth. The buboes were seated chiefly in the
glandular parts, the armpits and groin, but sometimes made their
appearance in the neck, cheeks, &c. Sometimes these suppurated
perfectly, and then they proved beneficial, but not otherwise.
Sometimes they suddenly disappeared, after having attained the
size of walnuts; and this retrocession was always supposed to be a
sign of approaching death. Sometimes they neither showed any sign
of inflammation nor were painful, and in such cases afforded no
relief. Similar swellings sometimes occured in the parotid glands,
but they were never equally beneficial with the buboes. _Carbuncles_
were gangrenous spots on the skin, resembling a burn, with black,
livid or red vesicles, bordered with an inflammatory ring, and soon
terminating in a hard, black eschar. The _anthrax_ is more prominent,
penetrating deeper into the adipose membrane, and attended with more
pain and inflammation. The disease was likewise attended with petechiæ
similar to those in putrid fevers, but larger; also with vibices,
which resembled the mark of a whip, and were considered, as well as
the petechiæ, as mortal signs. No distinct account of the pulse could
be given; as, after the disease became general, physicians did not
choose to feel the pulses of their patients but through a glove or
tobacco-leaf. Worms called _teretes_ were frequently discharged both
upwards and downwards. Women with child generally suffered abortion,
and were carried off by an uterine hæmorrhage.[107]

  [107] Bonetus relates, that in 1676 in a malignant fever at Borgo di
  Safia, the patients discharged live worms by the mouth, and adds that
  they were sooner killed by wine than any thing.

According to Sydenham, the plague begins with chilliness and shivering,
like the fit of an intermittent, succeeded in a little time by violent
vomiting and oppression at the breast, accompanied with its common
symptoms. These continue till the disease proves mortal, or the
kindly eruption of a bubo or parotis discharges the morbific matter.
Sometimes, though rarely, the disease is not preceded by any fever;
the purple spots, which denote immediate death, coming out even while
persons are abroad about their business. But this hardly ever happens
but in the beginning of a very fatal plague, and never while it is on
the decline, or in those years in which it is not epidemic. Sometimes
swellings appear without having been preceded either by a fever or
any other considerable symptom; but he conceives that some slight and
obscure shivering always precedes the seizure.

Mariti, in his travels through Cyprus, &c. says that the plague of 1760
began with loss of appetite, pain in the shoulders, head-ach extremely
violent, delirium, vomiting, with a most excruciating pain in that
part where the tumour by which the plague is characterised, is about
to break forth. Death often took place on the third day, and very few
lived beyond the thirteenth.

The Abbe’s definition of what he calls the plague, and which seems to
be the _pestilential bubo_ of the physicians, is somewhat singular.
“The plague (says he) is an oblong tumour, shaped like a pumpkin, which
is at first of a flesh colour; but it gradually becomes red, and at
length blueish; and this is a sign that the disease is incurable. If it
continues red, and a little after inclines to yellow, it is a sign that
a suppuration will take place: the swelling is then opened, and the
patient is sometimes cured.”

According to our author, the symptoms of the plague do not appear
till fifteen days after the infection is received; and this is the
reason of a law which subjects to a proof of twenty days every person
suspected of being diseased. In this plague it was observed that people
of the soundest constitutions were the most subject to it, and the
least capable of resisting it. On the other hand, it appeared to spare
weak and delicate persons, whose cure, in case of an attack, was much
less difficult. A greater number of Moors than of any other nation
were attacked by it; and when once they were seized, their case was
absolutely desperate. Those who had recovered from the disease were
less liable to a second attack, but were not absolutely safe. “I have
known some (says our author) who have been ill seven times, and have
died of it at last.”

Dr. McBride informs us that in the plague which raged at Marseilles and
the adjacent places in 1720, people on their first seizure seemed as if
intoxicated with drink; they lost the power of their limbs entirely,
and became so dejected that they gave themselves over to despair from
the very first attack. Along with the bilious vomitings and purgings
which generally took place on the second day, quantities of small worms
like ascarides were thrown off. The more plentiful these evacuations
were, the more salutary; for those who vomited and purged but little
sunk down, oppressed with the disease, and died before the fourth day,
covered with livid blotches and petechiæ; those who had the largest
evacuations had also the most plentiful eruptions of buboes and parotid
abscesses. When these appeared, the patients rose, walked about, and
became remarkably hungry; the heat and thirst subsided, but the face
continued pale and languid, the pulse hard and frequent. On the sixth,
seventh, or eighth day, if the suppuration stopped, and the humours
went back, then came on oppression, difficulty of breathing, furious
delirium and convulsions, which ended in death. When carbuncles, or
biles, with mortified sloughs, appeared in different parts of the body,
either alone or accompanied with the glandular swellings, the patients
scarcely ever escaped. In great numbers of people tumours appeared
without any previous febrile symptom, and, in a few cases, went off by
resolution; in others they continued in a schirrous state; but it was
best when the tumours came to suppuration.

These are the most remarkable symptoms of this fatal disease, which
have been recorded by the physicians of greatest eminence who have
written upon the subject. It remains still to give some particular
description of the buboes and carbuncles, which are supposed to
constitute in a particular manner the characteristic signs of the
distemper. Of these the following account, given by Dr. Alexander
Russel, seems to be sufficiently clear and explicit.

Only a very few, and such as died suddenly, were exempted from buboes,
but only about one half had carbuncles. In the latter plagues their
proportion was still smaller; but they seldom appeared earlier than in
the months of April or May. In 1742 and 1743, the buboes often appeared
on the first commencement of the distemper, sometimes not till twelve
hours after; in a few instances not till two or three days; but in
1744 they were sometimes the first symptoms of the disease. The buboes
were generally solitary, the inguinal and axillary more frequent than
the parotid. “The inguinal bubo for the most part was double; that is,
two distinct glands swelled in the same groin. The superior, which in
shape somewhat resembled a small cucumber, lay obliquely near the large
vessels of the thigh, lower than the venereal buboes are usually found,
and it was that which commonly came to suppuration; the inferior was
round, and in size much smaller. I once met with a case in which an
axillary bubo divided in like manner into two parts, one of which got
under the pectoral muscle, the other sunk deeper into the armpit: both
grew painful and inflamed, but that in the armpit only suppurated.”

The bubo was at first a small hard tumour, painful but not inflamed
externally. These indurated glands were deeply seated, sometimes
moveable, at others more or less fixed, but always painful to the
touch. Sometimes they would increase to a considerable size in a few
hours, with intense pain, then suddenly subside; and these changes
would take place several times in twenty-four hours. “An exacerbation
of the pestilential symptoms immediately upon the decrease of the
bubo, sometimes prompted me to imagine it owing to the retrocession
of the tumour; but this did not happen so constantly as to make me
think it was so in reality. The buboes, as far as I could learn, never
advanced regularly to maturation till such time as a critical sweat
had carried off the fever. In ten, twelve, or fifteen days, from the
first attack, they commonly suppurated; having been all along attended
with the usual symptoms of inflammatory tumours. But I have known
them sometimes, nay, frequently, disappear soon after the critical
sweat, and discuss completely without any detriment to the patient.
At other times, though grown to a pretty large size, the tumour,
about the height of the disease, would sink and mortify, without any
fatal consequences; for, as soon as the crisis was complete, the
mortification stopped, and the gangrened parts separating gradually,
left a deep ulcer, which healed without difficulty. I met with no
instance of a bubo in which fever did not either precede or follow the
eruption.”

On the subject of carbuncles, Dr. Patrick Russel observes, that “there
are certainly varieties in them, but perhaps these varieties have been
unnecessarily multiplied, from the same eruption having been viewed
in different stages of its progress; for all of them sooner or later
are covered with a black eschar.” Dr. Alexander Russel describes
them as follows: “The carbuncles were commonly protruded the second
day of the disease; and though the muscular and tendinous parts were
more especially affected, no part whatever could be said to be free
of them. The carbuncle at first resembled an angry confluent pock in
its inflammatory stage, but was attended with intense, burning pain,
and surrounded by a circle of a deep scarlet hue, which soon became
livid. By a progress very rapid, it then spread circularly, from the
size of a silver penny to an inch and an half, two inches, nay, even
three inches, diameter; and the supervening gangrene often penetrated
deep into the substance of the parts affected. In such of the sick
as recovered, the gangrene usually ceased spreading on the third day;
and, a day or two after, signs of suppuration were observed at the edge
of the black crust, the separation of which, advancing gradually, was
completed rather in less time than that of the eschar in issues made
by caustic. In cases where the patient died, I was informed (for I saw
none of those cases myself) that a quantity of ichorous matter oozed
from beneath the eschar, which remained itself shrivelled and hard,
without any favourable signs of separation or digestion.”[108]

  [108] Dr. Gotwald, formerly quoted, describes four varieties
  of carbuncles, the differences between which seem to be pretty
  distinctly marked. 1. “One kind rises pretty high, is of a dark
  brown colour, the cuticle appearing as if it were burnt, and it is
  surrounded with a lead-coloured circle. In the beginning it is no
  bigger than a pea, but, if not prevented, soon grows to the size
  of a crown piece; inwardly it is moister than the rest, and may be
  more easily separated. Its seat is generally in the fleshy parts,
  as on the shoulders, neck, hips, arms and legs. 2. The second lie a
  little deeper, and do not rise so high; the eschar in the middle is
  entirely dark and ash-coloured, full of small chops, as if it would
  burst by too great dryness: it has a strong lead-coloured circle,
  behind which the sound flesh looks red and shining. It eats into
  the flesh round about it, and takes deep root: it generally fixes
  in the most fleshy parts, as the buttocks, calves, &c. 3. The third
  is not very large at first; it appears like a blood swelling, not
  so dark as the former, with a wrinkled skin; as it increases, small
  blisters arise in the middle, and form an eschar, in little clusters,
  which, as an ingenious physician observed, were small carbuncles.
  They commonly are situated in membranous and tendinous parts about
  the knees, toes, and behind the ears, &c. 4. The fourth is the most
  curious, as Purman, in his treatise on the plague, has well observed.
  Sitonius calls them pale, livid, ulcerous papulae: they appear with a
  high, yellowish blister, which seems full of corruption: the circle
  round it is first red, then of an ash colour: the blister soon
  falls, and, with the carbuncle, appears scarce so big as a pepper
  corn, continually eating deeper and wider. They are seated upon the
  cartilaginous or gristly parts. Gotwald found them near the pit of
  the stomach, upon the cartilago ensiformis and short ribs. All the
  four take root and burn very violently at first, but the two former
  most of all.”

Dr. Alexander Russel also describes another kind of pustule, which he
says appeared in a small number of the sick, but which his brother Dr.
Patrick had no opportunity of observing in 1760. It had no livid or
discoloured circle surrounding it, but was filled with laudable pus;
and, when dry, the crust fell off, as in the distinct small-pox. This
was looked upon as a favourable symptom, all who had it happening to
recover.

We have now detailed, at considerable length, the symptoms of the
plague as mentioned by authors of great eminence. To give a detail
of _all_ that has been said upon this subject would be impossible;
neither indeed can it be thought necessary in the present treatise.
Whatever may have been omitted or too slightly mentioned in this
section, will naturally be considered when we come to treat of the
cure. It now therefore only remains to say, whether the approach of a
plague may be known by any visible signs, so that people might in some
measure prepare themselves for the ensuing calamity.

Were we in possession of an accurate and authentic history of the
world, this question might be very easily decided; but the uncertainty
of ancient records, the mutilated state of those which we do possess,
the diversity of opinions among mankind, and the unhappy disposition
to _misrepresent_, so common in all ages, render it very difficult to
say any thing upon the subject. If the theory hinted at in this section
(that plagues arise from some commotion in the electric fluid) can be
allowed to have any foundation in nature, then it ought to follow, that
the forerunners of pestilence would be some electric phenomena; and,
from a perusal of the first and second sections of this work, it will
appear that such an opinion is not altogether unfounded.[109]

  [109] See p. p. 61, 62.

The appearance of immense numbers of insects has likewise been
accounted a sign of approaching pestilence; but if we suppose their
appearance to be a _sign_, we can scarce imagine their putrefaction
to have been a _cause_, of pestilence. In the east we are informed
by Dr. Russel that the inhabitants of Aleppo account the appearance
of insects, and even _eclipses_, as presages of the plague. They
suppose also that the stillness of frogs is a sign of pestilence;
but the same author informs us that all these signs failed in 1760.
Violent earthquakes and famines seem to be more certain signs, though
even these are not always to be depended upon; it being evident
from historical accounts that pestilence has sometimes preceded,
and sometimes followed, earthquake and famine. Mr. Gibbon, however,
ascribes to the above-mentioned causes, viz. insects, earthquakes, and
even _comets_, the dreadful plague which took place in the reign of
Justinian. At least, all these preceded it; but perhaps the _insects_
were only meant to be accounted the cause of the plague. The cause
of the _insects_ must remain in obscurity. According to him, “In a
damp but stagnating air, this African fever is generated from the
putrefaction of animal substances, and especially from the swarms of
locusts, not less destructive to mankind in their death than in their
lives.”

This dreadful plague was preceded by comets and most violent
earthquakes. A remarkable comet appeared in 536, supposed to be the
great one observed by Sir Isaac Newton in 1680. This, we are told by
astronomers, revolves round the sun in a period of 575 years; but the
failure of astronomical predictions in the return of the expected
comets of 1759 and 1789, shew the futility of such calculations.
Another comet appeared in 539, and these comets were attended with
an extraordinary paleness of the sun. Mr. Gibbon observes, that
earthquakes, which he calls a fever of the earth, “raged with uncommon
violence during the reign of Justinian. Each year is marked by the
repetition of earthquakes of such character, that Constantinople has
been shaken above forty days; of such extent, that the shock has been
communicated to the whole surface of the globe, or at least of the
Roman empire. An impulsive or vibrating motion was felt; enormous
chasms were opened, huge and heavy bodies were discharged into the air,
the sea alternately advanced and retreated beyond its ordinary bounds,
and a mountain was torn from Liburnia, and thrown into the waves, where
it protected as a mole the new harbour of Botrys in Phenicia.”

According to Dr. Sydenham the plague at London in 1665 was preceded
by a very cold winter; the first continued till spring and went
off suddenly towards the end of March. Peripneumonies, pleurisies,
quinsies, and other inflammatory disorders, then made their appearance,
along with an epidemic fever of a particular kind, which did not yield
to the remedies successful in other epidemics. About the middle of
the year the plague began, and increased in violence till the autumnal
equinox, when it began to abate, and by the ensuing spring was entirely
gone. Our author says that the plague seldom rages violently in England
but once in thirty or forty years; but since his time, which is upwards
of a century, no plague hath appeared. He supposes the plague and
other epidemics to depend on some secret constitution of the air,
but pretends not to say what that constitution is. But, besides this
constitution, he is of opinion that there must be another circumstance,
viz. the receiving the effluvia or seminium from an infected person.
Thus he supposes that a single infected person is sufficient to poison
a whole country; the general mass of atmosphere being infected by the
breath of the diseased and the effluvia of the dead bodies. “Thus
(says he) the way of propagating this dreadful disease by infection is
rendered entirely unnecessary; for though a person be most cautiously
removed from the infected, yet the air received in by breathing will
of itself be sufficient to infect him, provided his juices be disposed
to receive the infection. I much doubt, if the disposition of the air,
though it be pestilential, is of itself able to produce the plague;
but the plague being always in some place or other, it is conveyed by
pestilential particles, or the coming of an infected person from some
place where it rages, to an uninfected one, and is not epidemic there,
unless the constitution of the air favours it. Otherwise I cannot
conceive how it should happen, that, when the plague rages violently in
one town in the same climate, a neighbouring one should totally escape
it, by strictly forbidding all intercourse with the infected places; an
instance of which we had some few years ago when the plague raged with
extreme violence in most parts of Italy; and yet the Grand Duke, by his
vigilance and prudence, entirely prevented its entering the borders
of Tuscany.” As to the nature of the disease, when once produced,
Dr. Sydenham is of opinion that it is altogether inflammatory; for
which he gives the following reasons: 1. The colour of blood taken
away that resembles that in pleuritic and rheumatic disorders. 2. The
carbuncles resemble the mark of _an actual cautery_. 3. The buboes are
equally disposed to inflammation with any other tumours that come to
suppuration. 4. The season of the year may be adduced in proof of this;
for between spring and summer, inflammatory disorders, as pleurisies,
quinsies, &c. are common.

Before we put an end to this section, it may now be proper to say a
few words by way of apology for the many apparent digressions from
the subject which have appeared in it. In the first place, then, the
work being intended for general inspection, and not merely for medical
readers, it became absolutely necessary to introduce a number of things
which for medical readers would have been totally superfluous. It was
to be supposed that the book might come into the hands of some who had
not read any thing concerning the structure of the body, who had not
heard of any of the systems of medicine now prevalent, or the different
doctrines they contain. It was impossible to write in an intelligible
manner for such people without giving some few hints concerning all
these subjects: the same consideration made it necessary to enter
pretty largely into the discoveries concerning the composition of
the atmosphere and various kinds of elastic fluids, concerning heat,
&c. In doing this the writer was under a necessity either to adopt
some of the doctrines he took notice of, or to animadvert upon them.
If he has ventured freely to give his sentiments, it is not with a
view to establish a theory of his own, but to direct the attention of
the reader to those natural agents which seem to be at present too
much overlooked, principally because they are less accessible to our
senses, and of consequence less subject to experiment, than others.
If therefore in this treatise it is suggested that the atmosphere
acts on the human body by its internal or latent heat, and by its
electricity, as well as by its other properties; if the writer is
inclined to believe that these are in fact the most powerful parts of
it; that we never can act without them, and that in short our life
and health are in immediate dependence upon them; I say, that none of
all these things are in opposition to any fact hitherto discovered,
either of the medical kind or any other. On the other hand, in all ages
physicians have sought for some constitution in the air, inexplicable,
and perpetually unknown, to which diseases might be ascribed that could
not be supposed to originate from any of its ordinary properties. To
explore this constitution is as great a desideratum at the present
moment as two thousand years ago; and any attempt to investigate it,
or a conjecture relating to it, cannot be supposed inconsistent with
any thing already discovered and ascertained. There are many things
which lead us to think that electricity is very much concerned in
diseases, and among the rest we must account the new discovery of Dr.
Perkins’s metallic conductors a very notable proof of it. These, when
first ushered into the world, were made by many a subject of ridicule;
but the evidence in favour of their efficacy, both in America and in
various parts of Europe, seems now to be decisive in their favour;
and, if they act at all, it is almost impossible to suggest any other
principle than that of electricity to which their efficacy can be
owing. No doubt it is difficult to draw the line properly betwixt
credulity and skepticism, but where credible testimony determines any
thing to have actually happened, or where solid reasoning gives room to
suppose any thing to be probable, it never can be invalidated by any
argument _a priori_ formed against the _possibility_ of such a thing
taking place.

In page 128 it is said, that M. Lavoisier, by introducing the new
chemical nomenclature, “has entailed the greatest curse upon the
science it ever met with.” All apology for this bold assertion is
absolutely necessary, and the quotation made from Dr. Ferriar may be
deemed inadequate, or perhaps misapplied. In passing this censure on
the nomenclature I wrote from experience. The new nomenclature, instead
of promoting _my_ improvement in chemistry, hath had a direct contrary
tendency. An instance of the inconvenience and ambiguity arising from
it is given p. 135, when speaking of Dr. Girtanner’s theory. But a
much more remarkable example is to be met with in the review of Dr.
Monro’s Chemical Treatise, where we find him censured for the very
same ambiguity taken notice of with regard to Dr. Girtanner. “He might
have observed (say the reviewers) the distinction between the hydrogen
and inflammable air, and between the oxygen and pure air, as well as
between the azote and impure air: he has mentioned these as synonimous,
whereas they are terms that express bases, or substances in a concrete
state (what I have called the condensable part) and the compounds
of these substances and heat, when they assume the form of gases or
elastic fluids.” (Monthly Rev. for 1790, p. 26.)

That the terms invented by Lavoisier and others have not been received
with perfect unanimity by the chemists of the present day, is evident
from Dr. Pearson’s “Translation of the New Chemical Nomenclature,”
which is not only a _translation_, but a _vindication_ of it. In the
course of his work he quotes the translator of the Chemical Dictionary
saying, that, “from the zeal of reforming language, such a number of
reformers may arise, that our ears will not be less stunned, nor our
understandings less perplexed, than if we were exposed to the clamour
of Babel, or the _thaw of words_ of Sir John Mandeville.” To this
Dr. Pearson replies, that there is no reason to fear any such bad
consequences. “The distinguished superiority of a system produced by
a _De Guyton_, a _Lavoisier_, or a _Bergman_, would surely supercede
the work of persons of _inferior ability_.” It is impossible to know
the persons here designated, unless the Doctor points them out. If he
chooses to call _himself_ one of them, we can have no objection. He
certainly has dissented, in one article, from “the system produced
by De Guyton, Lavoisier and Bergman,” and this is with regard to the
word _azote_. This is the term announced to us as the most proper for
denoting a certain kind of air. But Dr. Pearson determines _nitrogen_
to be more proper. Even this has not given entire satisfaction,
for Dr. Mitchell has adopted the word _septon_ in preference to
both _azote_ and _nitrogen_. Thus, instead of the original phrase
_phlogisticated air_, used by Dr. Priestley, we have four; for as
long as the works of Dr. Priestley remain, the original term will
be used by some, while with others it will be so much disused that
perhaps they will not understand it when it happens to occur. Nor are
corrections of this kind all that we have to fear. Professor Wiegleb,
who has written a System of Chemistry in quarto, has therein changed
almost all the nomenclature invented by Lavoisier. Instead of it he
gives a nomenclature of his own, in which he makes very much use of
the termination _cratia_, from a Greek word signifying strength; thus,
instead of saying the _acid of fluor_, we are to say _fluoricratia_. I
must confess that to me the perpetual repetition of this termination
has a very ridiculous appearance; but the misfortune is, that in the
case of nomenclatures we have no choice. We cannot choose one and
reject another: good or bad, we must take both; and were an hundred
new ones to arise, we must be condemned to learn them all. Nor is even
this the worst. Wiegleb’s scholars, for instance, accustomed to the
language of their teacher, will be apt to put it into their writings,
perhaps without proper explanation; and thus such writings must be
unintelligible both to old and new chemists: and thus it will be with
as many others as choose to invent new chemical terms.

Were this a proper place for entering into a discussion of Lavoisier’s
nomenclature, it might easily be shown that the terms are not more
proper than those which preceded them; but no real inconvenience can
arise from the propriety or impropriety of a mere name. It is the
_resemblance_ of the terms to one another, and the facility with
which mistakes may be made, that gives just ground of complaint.
Nor is it any just reason to accuse a person of want of judgment or
carelessness because he hath mistaken these terms. We see that even
Dr. Monro has not attended to every circumstance; and if a man of his
experience and accuracy hath been inaccurate in this respect, what
is to be expected from others? How easily may the words _sulfate_,
_sulfite_, _sulphuret_ and _sulphure_, be mistaken for one another,
either in writing or conversation! Yet a mistake of this kind would
totally pervert the meaning of the person who used it. The scripture
finds fault with those who make people offenders for a _word_; but here
we are in danger of being made offenders for a _letter_. In short,
taking into account the inconveniences arising from this nomenclature
itself, the numberless corrections and amendments (no matter whether
real or imaginary) to which it may be subjected, and the number of
others totally different from it which may arise, I cannot help looking
upon the introduction of it into chemistry as an evil of the first
magnitude; an evil which cannot be remedied by any art, but must
continually become worse and worse.



SECTION IV.

_Of the best Methods of Preventing the Plague._


These methods may be classed in the following manner: 1. Those most
proper for avoiding the infection, supposing the disease to be
infectious. 2. The proper mode of resisting or removing those local
causes which may give rise to it, or may co-operate with the infectious
matter in giving greater force to the disease, should it happen to be
introduced; and, 3. The best method of preparing the body for resisting
pestilential attacks, should we happen to be so situated that no
external method of defence could be used.

With regard to the first of these intentions the flying from places
infected has been so universally recommended, and so generally
received, that the precept has been made up into the following
proverbial Latin distich:

  “Hæc tria tabificam tollunt adverbia pestem
  Mox, longe, tarde, cede, recede, redi.”

  _These words prevent the plague’s infectious pain,
  Go_ quick, _fly_ far, _and_ slow _return again._

This maxim hath been put in execution in all ages, but often with so
little regard to humanity that it cannot by any means be recommended
without very considerable limitation. The reparation of the sick from
all promiscous intercourse with the sound, in times of pestilence,
seems to be dictated by common sense; but this may be done without
killing them, or leaving them to expire in the miserable state to which
they are reduced by the disease. Mr. Howard informs us that in some
places ships which have the plague on board are chased away and burnt;
and instances of cruelty with regard to infested individuals have been
formerly mentioned. Dr. Mertens is of opinion that cutting off all
the communication between the infected and healthy is the only means
of preventing the disease from spreading. The good of this practice
was observed in one of the hospitals at Moscow. All the avenues to it
were shut up, but one which was strictly guarded, and every suspected
article prohibited from entering. Infected clothes and utensils were
burned, and the houses where the sick had lived were purified by the
fumes of vinegar and gun-powder.

In this mode of prevention it is of the utmost consequence to ascertain
the distance to which the contagion extends; in the next place to know
whether by means of clothes, cotton or other kinds of merchandise it
may be imported from one place to another; and in the third place
how long the infection may remain in these kinds of goods; so that
people may know when the danger is over. As to the distance, it seems
to be generally agreed, that it is but small. Some of the answers to
Mr. Howard by the physicians of whom he inquired, have been already
related. Of the infection of the plague he speaks in the following
manner:

“In my opinion this distemper is not generally to be taken by the
touch, any more than the gaol-fever or small-pox; but either by
inoculation, or by taking in with the breath the putrid effluvia which
hover round the infected body; and which, when admitted, set the
whole mass of blood into fermentation, and sometimes so suddenly and
violently as to destroy its whole texture, and to produce putrefaction
and death in 48 hours. Those effluvia are capable of being carried
from one place to another, upon any substance where what is called
_scent_ can lodge; as upon wool, cotton, &c. and in the same manner
that the smell of tobaco is carried from one place to another.

“The infection in the air does not extend far from the infected object,
but lurks chiefly (like that near carrion) to the leeward of it. I am
so assured of this, that I have not scrupled going, in the open air,
to windward of a person ill of the plague to feel his pulse. The rich
are less liable to the plague than the poor, both because they are more
careful to avoid infection, and have more large and airy apartments,
and because they are more cleanly, and live on better food, and plenty
of vegetables; and this I suppose is the reason why Protestants are
less liable to this distemper than Catholics during their times of
fasting, and likewise why the generality of Europeans are less liable
to it than the Greeks, and particularly Jews.

“It is remarkable that, when the corpse is cold of a person dead of the
plague, it does not infect the air by any noxious exhalations. This
is so much believed in Turky, that the people there are not afraid to
handle such corpses. The governor of the French hospital at Smyrna told
me, that, in the last dreadful plague there, his house was rendered
almost intolerable by an offensive scent; especially if he opened any
of those windows which looked towards the great burying-ground, where
numbers every day were left unburied; but that it had no effect on the
health of himself or family.”

It is likewise a matter of the utmost importance to ascertain the time
at which the disease is introduced into any town or district. Dr.
Canestrinus, in a treatise on this distemper, published at Saltzburg,
complains greatly of the dissensions among physicians concerning the
nature of the distemper, owing to which its existence is frequently
denied, and thus its ravages are propagated immensely beyond the
limits which might otherwise circumscribe them. Of this he gives the
following remarkable instance: “In the year 1770 a disease with
uncommon symptoms prevailed at Bodrogh in Upper Hungary, which carried
off a number of persons in a short time. A physician of the county
of Zemplin was sent to inquire into the nature of the malady. He
reported that the disease was of a suspicious nature, having a great
resemblance to the plague. His report was received by the nobility and
health-officers with indignation, as if untrue. Another was sent, who,
without hesitation, pronounced the disease an epidemic scurvy. In the
mean time the disease, being left to itself, spread wider, and raged
with such violence as to carry off seventeen persons in one house.
The nature of the disease now becoming apparent, proper measures were
taken, and the infected separated from the sound, by which means the
disease was confined within a small district.[110]” With regard to the
infection of the disease, or _contagion_, as it is commonly called,
he expresses himself as follows: “The air is not capable of diffusing
the contagion to any considerable distance from the infected subject
unimpaired in its power, but, like other poisonous matter, it is
capable of dilution in the atmosphere, so as to be rendered at length
innoxious. The contagion of the plague will be entirely prevented from
spreading if all access to, and all intercourse with, the sick be
strictly prohibited: whence the following forms a safe and infallible
prophylactic of the disease:

  [110] Medical Review, vol. iii, p. 257.

  “Mox, longe, tarde, cede, recede, redi.
  _Go_ quick, _fly_ far, _and_ slow _return again._”

“No change in the habit takes place previous to the action of the
contagion, but the body is from the first equally susceptible of it
as of the itch, or any other infectious disease. Whilst the plague
ceases in the civilized parts of Europe spontaneously, or by human
precautions, its revival is prevented, from the care that is bestowed
in purifying or destroying every infected substance. In the east,
on the contrary, this precaution is totally neglected; whence it is
probable that the disease is not reproduced anew, but that it is
perpetuated by the former fomes, as happens with us in the small-pox.
The matter producing the ordinary epidemics is widely diffused in the
atmosphere, and capable of infecting through a widely extended space.
The pestilential poison, on the contrary, is confined to the vicinity
of the affected body, and becomes so dilute at the distance of a few
paces only as to be incapable of further action. Hence it appears that
the plague is much easier avoided than epidemic disorders. The more
abundant the contagious matter is, the further probably is the power of
its infection carried. This is the reason that the mere separation of
the sick and suspected from the healthy is so much more efficacious in
destroying it at its commencement than at a later period. To restrain
epidemics within bounds is impossible; but with the contagion of the
plague, it is certain that it can be confined by art to a narrow spot.”

Of the truth of this last assertion our author gives a remarkable,
instance in his own practice about the time that the plague stopped
at Bodrogh. Having been sent into Cassovia, along with two other
physicians, they were informed by the surgeon of the lazaretto, that
an unusual disease had broken out in the district of Zboina, which had
suddenly proved fatal to many. On inquiry it was found that it had come
from Bodrogh in the following manner: Two young men, returning from the
vintage at Tokay, slept a night in an infected house, and stole some
clothes belonging to those who had died of the plague. He who carried
the clothes died by the way: his father carried home the bundle, kept
them unpacked for some weeks, but having at last worn them, he and
all his family fell victims to the same disease. The pestilence began
to spread, and shewed an appearance of great malignity. Our author
did not hesitate to declare its true nature, and in consequence of
his declaration all communication was cut off between the adjacent
countries and the infected spot, by a cordon of the military. The
infected were separated from such as were only suspected, and these
last from the sound: three infected houses were destroyed by fire,
and other means (to be afterwards related) were used with a view to
destroy the contagion itself. Thus the disease was prevented from
spreading; and none but such as had been previously suspected were
seized.

To the same purpose the Abbe Poiret thinks it an easy matter to
extinguish the plague entirely. He was a witness to the ravages of
the disease in Barbary, and thinks it the most easily avoided of
any distemper; but the misfortune is, that there are many things in
their own nature very easily accomplished, which the inattention or
perverseness of mankind render utterly impracticable. Such, it is to be
feared, is the extinction of the plague by the means just mentioned;
for though these means might be enforced in a country district or small
town, yet, where the pestilence enters a large and populous city,
there are so many modes of concealing its existence, and the unknown
intercourse of the sick with the sound must be so frequent, that it
seems scarce possible to prevent the malady from spreading.

In London, whether it arose from a neglect of using the precautions
for too long a time, or from any other cause, cannot well be known;
but the attempts of the magistrates to separate the sick from the
sound certainly were not attended with any good consequence. “The
consternation (says Dr. Hodges) of those who were thus separated from
all society, unless of the infected, was inexpressible, and the dismal
apprehensions it laid them under made them but an easier prey to the
devouring enemy. And this seclusion was on this account much the more
intolerable, because, if a fresh person was seized in the same house
but a day before another had finished the quarantine, it was to be
performed over again; which occasioned such tedious confinements of
sick and well together, as sometimes caused the loss of the whole.
Moreover, this shutting up of infected houses made the neighbours fly
from theirs, who might otherwise have been a help to them on many
accounts; and I verily believe that many who were lost might have
been alive, had not the tragical mark upon their doors driven proper
assistance from them. And this is confirmed by the examples of other
pestilential contagions, which have been observed not to cease until
the doors of the sick were set open, and they had the privilege of
going abroad.” The Doctor sets forth also the arguments on the other
side; but whatever _might_ have been the advantages of a separation
of the sick from the healthy, if conducted in a manner less capable
of hurting the feelings of humanity, it is evident that in the London
plague the methods attempted to prevent the disease at least did no
good.

In countries where the plague generally prevails, and the Europeans are
_united_ in the opinion that it is necessary to separate themselves
from the natives, the method of shutting up is attended with the most
salutary effects, as has been attested by almost every traveller who
has resided there for any time. Accidents among them are very rare,
though not altogether without example. At Alexandria in Egypt, M.
Volney tells us, that as soon as the plague makes its appearance the
European merchants shut themselves up in their _khans_ and have no
communication with the rest of the city. Their provisions are deposited
at the gate of the khan, and received there by the porter, who takes
them up with iron tongs, and plunges them into a barrel of water
provided for the purpose. If it is necessary to speak to any one, they
keep at such a distance as to prevent touching with their clothes, or
breathing on one another; by which means they preserve themselves from
this dreadful calamity, unless by some accidental neglect of these
precautions. Some years ago a cat, which passed by one of the terraces
into the houses of the French merchants at Cairo, conveyed the plague
to two of them, one of whom died. This state of imprisonment continues
for three or four months, during which time they have no other
amusement than walking in the evening on the terraces, or playing at
cards.

The doctrine of predestination, and still more the barbarism of the
government, have hitherto prevented the Turks from attempting to
guard against this destructive disease: the success, however, of
the precautions taken by the French, has of late begun to make some
impression upon many of them. The Christians of the country who traffic
with the French merchants, would shut themselves up like them; but this
cannot be done without permission from the Porte. A lazaretto was some
years ago established at Tunis; but the Turkish police is every where
so wretched, that little can be hoped for from those establishments,
notwithstanding their extreme importance to commerce and the safety
to the Mediterranean states. The very last year afforded a proof of
this; for as violent a plague as ever was known broke out there. It was
brought by vessels coming from Constantinople, the masters of which
corrupted the guards, and came into port without performing quarantine.
Water carriers have never been attacked by it.

Mariti says, that in the island of Cyprus, and on the continent of
Syria, every European, on the slighted appearance of the plague, after
taking the necessary precautions, shuts himself up with his family.
The Mahometans alone, more intrepid, go abroad as usual, converse with
each other, give such assistance to each other as may be necessary, and
often fly to the relief of a Christian when deserted by his friends.
This arises from their belief in predestination. The Mahometans of
Syria, however, less familiarized with this scourge, make use of some
precautions, which were augmented in 1760. They published an ordonnance
forbidding every vessel attacked by the plague to enter their ports:
but their vigilance in this respect was so remiss, that it was not
sufficient to prevent the contagion. The governor of Acre checked
the progress of this plague, by giving the inhabitants the means of
retiring from its ravages; and these means, though absolutely contrary
to the dogmas of the Mahometan religion, were eagerly embraced. The
Europeans became their models; and the governor, after deriving
from them every necessary information, shut himself up, after their
example, together with his numerous family. The mufti alone, being the
protector of the Mahometan law, cannot imitate a conduct which that
law condemns. Instead of shutting himself up in a prudent confinement,
he thundered forth against this new method, reproached the governor for
his conduct, and, having treated him as an impious person, threatened
him with all the vengeance of Heaven. The governor, however, only
laughed at this pious folly of the mufti, and sent a detachment of
soldiers to impose on him a fine of two hundred and fifty sequins, for
having dared to ascribe to him, in matters of religion, an ignorance,
from every suspicion of which his age ought to have secured him.

In the time of plague, the proper precautions are, to shut one’s self
closely up, and to receive no provisions or other things, except those
on which the plague has no influence. The people of Syria, however, in
1760, admitted every kind of provisions without fear, but not without
using certain precautions. They did not receive warm bread; flesh of
every kind was thoroughly washed, and milk was strained through a
linen cloth, in order to free it from the smallest particle of animal
hair. All kinds of pulse were soaked in water, and they abstained from
peaches, apricots, and other fruits which are covered with a downy
rind. Fowls were cooked out of the house, for fear that some small
feather might adhere to them. Flowers were altogether proscribed.
Letters were opened by the person who brought them; and they were never
read until they had been steeped long enough in vinegar to be purified
without effacing the writing. Every thing was received into the house
by means of a rope of herbage suspended from a window. The governor
employed every precaution which he thought likely to guard him from the
contagion; and, by shutting himself closely up, he set an example which
the rest of the Mahometans did not neglect to follow. Besides this he
caused the streets to be cleansed; and carried his vigilance so far as
to forbid the caravans which arrived from Damascus, where the plague
swept off four or five thousand people every day, to enter the city.
He obliged them to submit to a proof of eight days without the walls,
and established regulations of the same kind respecting vessels coming
from Alexandria or Damietta. One precaution taken in the time of plague
is, to prevent _cats_ from entering houses: an open war is therefore
declared against these animals; and, wherever they are found, they are
knocked on the head with large clubs. This is a cruelty absolutely
necessary; for there is no vehicle that will convey the infection
with more certainty or rapidity than the hair of cats. Rats and mice
multiply in consequence of their destruction; but there is no instance
of their ever having propagated the plague. This disease, when it
attacks men, spares quadrupeds and birds. The furs of the one, and the
feathers of the other, however, attract and communicate the infection.
People ought particularly to keep from goats and sheep; from horses and
oxen little is to be apprehended.

All these precautions were sometimes ineffectual. The French at
Acre, who there, as well as throughout Syria, are collected into one
quarter, used every precaution that could be thought of, yet, on the
30th of March, 1760, five of them were infected. They belonged to the
hospital of the Holy Land, and the monks were instantly ordered to shut
themselves up. They did so; and eight of them died, one only escaping.

Mr. Howard likewise gives particular accounts of the precautions used
in several different countries through which he travelled. In Malta two
kinds of quarantine are performed; one for ships with clean bills, the
other for those with foul. The former lasts 18 days.[111] The crews
and passengers are allowed to buy provisions, and converse by means of
enclosures with stone posts and palisadoes. A letter received from a
Turkish ship was taken by a pair of iron tongs, dipped in vinegar, put
into a case, and laid for about a quarter of an hour on a wire grate
under which straw and perfumes had been burnt; after which the letter
was taken out and opened by one of the directors. In this island ships
with foul bills must perform quarantine eighty days; but, at the end
of forty, may change their station. The different kinds of goods are
separated and placed in proper order under cover. The cottons are
taken out of the bags containing them, and placed on rows of piles on
boards, laid on stone pillars about 18 inches from the floors; and, in
repacking them they are flung over a man who gets into the bags, and
treads down the cotton; the consequence must be the exposing him to
great danger, should any infection remain.

  [111] At Aleppo 20. (Russel.)

Mr. Howard took a voyage to Venice in a ship with a foul bill, on
purpose to know every thing relative to the performance of quarantine.
“A messenger (says he) came in a gondola to conduct me to the new
lazaretto. I was placed, with my baggage, in a boat fastened by a cord
ten feet long to another boat in which were six rowers. When I came
near the landing place the cord was loosed, and my boat was pushed with
a pole on the shore, where I was met by the person appointed to be my
guard. Soon after unloading the boat, the sub-prior came and showed
me my lodging; a very dirty room, full of vermin, and without table,
chair or bed. That day and the next morning I employed a person to wash
my room; but this did not remove the offensiveness of it, or prevent
that constant head-ach which I had been used to feel in visiting other
lazarettos and some of the hospitals in Turky. My guard sent a report
of my health to the office, and, on the representation of our consul,
I was removed to the old lazaretto. Having brought a letter to the
prior from the Venetian ambassador at Constantinople, I hoped now to
have had a comfortable lodging. But I was not so happy. The apartment,
consisting of an upper and lower room, was no less disagreeable and
offensive than the former. I preferred lying in the lower room, on a
brick floor, where I was almost surrounded by water. After six days,
however, the prior removed me to an apartment in some respects better,
and consisting of four rooms. Here I had a pleasant view; but the
rooms were without furniture, very dirty, and no less offensive than
the sick wards of the worst hospital. The walls of my chamber, not
having been cleaned perhaps for half a century, were saturated with
infection. I got them washed repeatedly with boiling water, to remove
the offensive smell, but without any effect. My appetite failed, and
I concluded I was in danger of the slow hospital fever. I proposed
whitewashing my room with lime slaked in boiling water, but was opposed
by strong prejudices. I got this, however, done one morning through the
assistance of the British consul, who supplied me with a _quarter_ of
a bushel of fresh lime for that purpose. The consequence was, that my
room was immediately rendered so sweet and fresh, that I was able to
drink tea in it in the afternoon, and to lie in it the following night.
On the next day the walls were dry, as well as sweet, and in a few
days I recovered my appetite. This room was lime-whited in November,
and in a very rainy season. In the following March, in complaining
to the under sheriffs in Newgate of their inattention to the clause
which orders this in the act of parliament for securing the health of
prisoners, their excuse was, that they were afraid of dampness.”

An health-office was established at Venice in 1448, in the midst of a
very destructive pestilence. The old and new lazarettos are both built
on little islands, surrounded not only by canals, but high walls.
They have only a ground floor, and one over it, and are divided and
subdivided into a great number of apartments, each having an open
court in front, with plats of grass, which is not suffered to grow too
high; nor are any trees suffered to grow within this district, or a
good way from it. The internal government is managed by a prior, who
must not be related to the magistracy nor any of its ministers. He
must have no interest nor concern in shipping nor in trade. He must
see all the gates and doors of the apartments locked every evening by
sunset; he takes the keys into his possession, and suffers them not to
be opened before sunrise; and, in case of any suspicion of infection,
the gates must be kept constantly locked, and opened only for necessary
occurrences in presence of the prior. He must not suffer dogs, cats,
&c. to lodge in the lazaretto. He must neither buy nor sell, nor suffer
others to do so, within the lazaretto. No fishing boats or other small
craft to come within a certain distance, or keep communication with
those performing quarantine. Provisions are received by poles seven
or eight feet long, and the money dipped in vinegar and salt water
before it is received. The prior and his substitute must carefully
avoid touching either goods or passengers in quarantine, and for this
purpose they keep a cane to make those who approach them keep their
proper distance; but if by an unfortunate accident they should be
contaminated, they must perform quarantine. Any person maliciously
touching them is liable to punishment.

Ships are strictly forbid to use any ropes but such as are tarred.
Wool, silk, cotton-wool, woollen and linen clothes, and furs
especially, are accounted the most dangerous goods. Animals with long
hair are subject to full quarantine; but short haired ones purged by
swimming ashore; feathered animals, by sprinkling with vinegar till wet.

The celebrated Dr. Mead, though an enemy to the cruel mode of
abandoning the sick, or treating them with any kind of harshness, was
perfectly sensible of the necessity of using every precaution for
preventing pestilential contagion from being imported. In his opinion
it is not sufficient that ships should perform quarantine, “the only
use of this being to observe whether any die among them. For infection
may be preserved so long in clothes among which it is once lodged,
that as much, nay, more of it, if sickness continues in the ship, may
be brought on shore than at the beginning of the forty days, unless
a new quarantine be begun every time any person dies; which might
not end but with the destruction of the whole ship’s crew.” He is
therefore of opinion that lazarettos ought to be established on small
islands near the sea-coast; and in this Mr. Howard agrees with him.
The latter recommends the lazaretto at Leghorn as the best in Europe.
Dr. Mead also very much insists on the utility of destroying the
clothes of the sick, because, says he, they harbour the very _essence
of the contagion_. He quotes in favour of this opinion what Boccacio
says he _saw_ at Florence in 1348; viz. that two hogs, finding in the
streets the rags which had been thrown out from off a poor man dead of
the disease, after snuffling upon them, and tearing them with their
teeth, fell into convulsions, and died in two hours. This is one of
the things which Dr. Moseley looks upon to be incredible. It is indeed
very marvellous, and seems to be contradicted by M. Deidier’s account
of the dog at Marseilles who swallowed with impunity the filthy pus
and pestilential matter adhering to the dressings of plague sores:
but, when a person of credit informs us that he _saw_ any thing,
we scarce know how to contradict him. The evidence of pestilential
contagion adhering to clothes, does not depend on such accounts. That
lately quoted from Dr. Canestrinus is decisive on the subject; and he
informs us that one of the methods used by himself to stop the plague
in Zboina, above mentioned, was, the burning of the clothes of infected
persons. He says that the pestilential contagion resembles that of the
small-pox, in being of a fixed nature; and that all who studiously
avoided communication with the sick, or with whatever fomes might carry
the contagion, escaped it altogether. “That the contagion of the plague
(says he) may lie dormant for a considerable time, and be carried to
a great distance by the medium of packages, &c. and again revive with
its former violence, is proved by various circumstances. _Chenot_
relates, in his treatise on the plague which raged in Transylvania,
that the infection was revived a whole year after it had disappeared;
and other similar instances are adduced.” If this revival happened
from infected clothes or soft goods, it shows them to be dangerous
in the extreme; but of this we have not any direct proof, neither
indeed is such a belief quite consistent with what takes place in all
plagues, viz. that the clothes of the infected are worn by the sound,
without producing any reinfection. In the great plague at London, for
instance, where an hundred thousand probably perished, and a much
greater number must have been infected, we cannot suppose that all the
clothes belonging to such an immense multitude were burned, or never
made use of again. It is of necessity therefore that we suppose the
pestilential contagion to become effete, and to lose its virulence,
after some time; and this seems to be very much hastened by exposure to
the atmosphere. The doing of this, however, by obliging people to put
their naked arms into bales of suspected goods, has such an appearance
of cruelty, that Dr. Mead has proposed to judge of the presence or
absence of infection by allowing little birds to fly about among them;
“because (says he) it has been observed, in times of the plague, that
the country has been forsaken by the birds; and those kept in houses
have many of them died.” But, though he says this upon very great
authority, no less than that of Diemerbroeck, yet we can by no means
look upon the fact to be absolutely determined. Dr. Russel indeed says
that the desertion of the birds is looked upon by the Turks to be the
_sign_ of an approaching plague; but this failed in 1760. Thucydides
says that birds of prey deserted the territory of Athens during the
great plague in his time; and he supposes them to have been poisoned by
feeding upon the bodies of such as died of the disease. It is possible
that such food might be disagreeable to them, but no proof is brought
of any of them having been actually poisoned by it. As for birds kept
in houses, it is possible that in a time of general calamity they might
have been neglected, and died for want of proper food, &c. Dr. Mead
also quotes an instance which cannot be credited in a consistency with
undoubted testimonies that pestilential contagion does not extend but
for a very little way. Upon opening an infected bale of wool in the
field near Cairo, “two Turks employed in the work were immediately
killed, and some birds which happened to fly over the place dropped
down dead.” Such accounts have arisen from a supposition that the whole
mass of atmosphere was violently infected; but this would be totally
inconsistent with the life of any human creature, and we may well put
down this, as that of pestilential infection arising from cities
like a cloud, as merely chimerical.[112] It is too well known that
pestilential contagion, instead of soaring in the air, keeps very near
the ground.

  [112] About the mouth of the river Gambia in Africa, after the annual
  inundation of the river, the putrefaction of the mud, mixed with
  animal and vegetable substances, becomes so great, that the birds
  manifest their disgust by soaring to an immense height in the air.
  This is a natural consequence of the levity of putrefactive vapours
  compared with the common atmosphere. As these vapours, however, are
  composed of several kinds of gases, it is possible that some may
  descend, while others ascend; and thus the contagious part, tending
  to the earth, may violently affect the people who are confined among
  it, while the birds escape; but there is still wanting some positive
  evidence that ever the true plague did arise from this cause.

We now come to the second mode of prevention, viz. removing these
local causes which, in the opinion of some, may produce a plague in
any country, and, in that of others, may increase or set in action the
contagion previously existing. These causes have been enumerated by the
late Dr. Smith,[113] in a Dissertation on the pestilential Diseases
which at different times appeared in the Athenian, Carthaginian and
Roman armies, in the neighbourhood of Syracuse. They are, 1. The
climate and season. 2. The situation of the armies; and, 3. Their
condition. The climate of the island of Sicily in general he observes
is extremely pleasant at some seasons of the year; in the neighbourhood
of Syracuse particularly storms are so infrequent during the former
part of the year, that the sun is never obscured for a whole day.
Even in the month of January, however, the weather is warm, and as
the season advances the heat becomes insupportable. In autumn it is
rendered somewhat unpleasant and unhealthy by the frequent rains and
chillness of the evenings. But, in particular places, during the
hottest season, nothing can exceed its unhealthiness. According to
Barichten, “the least stagnant water is sufficient, in the heats of
summer, to poison the atmosphere: its effects on the countenances of
the poor people who live in its vicinity are evident; and a stranger
who travels through the island in this season ought to avoid ever
passing a night near them.” De Non says, that “as soon as the sun
enters the Lion, this country becomes the house of death: fevers of
the most malignant kind seize on the imprudent or unfortunate wretch
that spends a night near them (ponds and marshes) and few escape with
life when attacked by so virulent a disorder.”

  [113] Med. Repository, vol. ii, p. 367.

To the poisonous effluvia of these marshes the Doctor attributes, in
an especial manner, the plagues which took place in the armies. In the
second year of the Peloponnesian war, the Athenian army was encamped,
as we are told by Thucydides, “upon marshy and unwholesome ground;”
and that such kind of encampments will produce diseases in an army
is well known. In the time of Dionysius, when the Carthaginian army
under Imilco suffered so dreadfully, or rather was totally destroyed,
his camp was situated on an eminence between two morasses, the heat
at that time being excessive. Hannibal, the predecessor of Imilco,
had also lost great part of his army by a plague, though he had been
encamped in a healthy situation; but, in order to raise a wall which
should overlook the city, he had taken the materials of the tombs
found in the common burial place, the city at that time containing
two hundred thousand inhabitants. “From the uncovering and disturbing
of so many dead bodies (says our author) arose a terrible pestilence,
which carried off immense numbers of the Carthaginians, and amongst the
rest the general himself.” To the unhealthy situation of the armies
also the Doctor ascribes the plague which took place in the Roman
and Carthaginian camps in the time of the second punic war; and the
Carthaginians suffered most, by reason of their being nearer to the
marshes. The state of mind, the cleanliness of the person, &c. also
must be taken into account; and our author shows that neither of these
could be supposed favourable to the Carthaginians.

That personal cleanliness, and breathing pure air, should contribute
to the health of individuals, or to any number of them collected
into camps or cities, seems to be agreeable to reason and common
sense; nevertheless we find that this has been denied, and even Dr.
Canestrinus says that “in the plague of Lyons and Marseilles it was
observed, that the most populous parts of these cities, _where the
streets were narrow and filthy_, suffered _less_ from the disease than
those which were more airy and clean. At the time of the plague in
London in the time of Charles II, the physicians advised that all the
_privies_ should be opened and exposed; the fetid odour from which
having pervaded the city, the plague was stopped! Is it from this cause
(the author asks) that the plague has seldomer visited Spain, the towns
of which are intolerably offensive from their want of cleanliness?”[114]

  [114] Medical Review, vol. iii, p. 260.

This certainly seems a very strange doctrine, nevertheless the fact
that Spain is but little subject to the plague seems undeniable, and as
it is no less certain that the towns are excessively filthy, it would
seem that cleanliness is not effectual in preventing it. But, however
agreeable the smell of human excrements may be to the Spaniards, or
to the English physicians in former times, it seems to be less so at
present. “I am persuaded (says Dr. Ferriar) that mischief frequently
arises from a practice common in narrow back streets of leaving the
vaults of privies open. I have often observed that fevers prevail most
in houses exposed to the effluvia of dunghills in such situations.”
In Spain the opinion seems to have been but lately eradicated; for
some years ago, an order having been issued by government that the
streets of Madrid should be kept somewhat cleaner, the people were
so much exasperated at being threatened with the loss of the savoury
odour, that a rebellion had almost ensued, and the physicians declared
the smell of human excrements to be the most wholesome thing in the
world.[115]

  [115] It seems, however, of late, that at least the city of Madrid is
  kept clean. Swinburne says, speaking of the palace at Madrid, “To the
  west it has the town, the three principal streets of which terminate
  in the Pravo. These are three noble openings, excellently paved, and
  clean even to a nicety; indeed so are most of the streets of Madrid
  since the edict for paving and cleaning them.[116] The foreigners
  that resided here before that time, shudder at the very recollection
  of its former filth. Some of the natives regret the old stinks and
  nastiness; as they pretend that the air of Madrid is so subtil as
  to require a proper mixture of grosser effluvia, to prevent its
  pernicious effects upon the constitution. The extremes of cold and
  heat are astonishing in this place, and the winds so searching, that
  all the Spaniards wear leathern under waistcoats, to preserve their
  chests; for they pervade every other kind of clothing.”

  The former filthiness of Madrid, together with its being situated in
  a climate exposed to the vicissitudes of extreme heat and cold, and
  its exemption from the plague under those circumstances, certainly
  presents a most solid objection to the theory of the domestic origin
  of plague. To the same purpose see below the remarks on the climate
  of China.

  [116] Dillon has a like remark in his “Travels through Spain.”

That the confinement of human effluvia, along with heat and want of
water, will produce a malignant fever, is certain from the example
of the unfortunate people confined in the Black Hole at Calcutta. In
this case the distemper seems to justify the opinion that plague may
be artificially produced, perhaps more than any other upon record; for
Dr. Ferriar informs us that it was attended with eruptions resembling
those of the true plague. In this case, however, the confinement was
beyond example in any situation which can be supposed incident to a
city or camp. There is no country in the world where the inhabitants
are equally numerous with those of the empire of China, its population
at present being estimated by Sir George Staunton at _three hundred
and thirty-three millions_, a number equal to _one third_ of the
supposed inhabitants of the whole globe; of consequence the cities
must be immensely crowded with inhabitants; yet it remains free from
plagues. Human effluvia therefore, in the most populous state in which
mankind can exist in society, _are not_ able to taint the atmosphere
of a country or city. The following is Dr. Clark’s account of that
celebrated empire: “The whole empire of China is represented to be
extremely delightful; the soil rich, the air pure, and the industry of
the inhabitants astonishing. As it produces every luxury and necessary
of life, it is justly esteemed one of the most fertile countries in the
world. As the Chinese prohibit emigration, and seldom or never engage
in war, their country is extremely populous. Every river maintains a
proportion of inhabitants adequate to the land, whose families live
continually in boats, without having any other place of residence.
Their number of people lays them under the necessity of carrying
industry to the greatest height; for otherwise their country, fertile
as it naturally is, would be insufficient to maintain the inhabitants.
Every inch of land is cultivated; no forests nor woods, nor even a
single tree, is suffered to obstruct the labours of the husbandman.
Canals are cut every where to water the fields, and marshes are manured
for the cultivation of rice. By these means health and plenty are, in a
great measure, the portion of its inhabitants through all the seasons
of the year. The only terrible and fatal diseases to which they seem to
be subject are the small-pox and leprosy.”

But, though our author determines in general that the air of China is
pure, this cannot apply to every part of it without exception. On the
contrary he describes in the following manner Wampoa, a village about
fourteen or sixteen miles below the city of Canton, on Canton river:
“It is the usual station of all European ships in this river. On one
side the land is low, marshy, and covered with water, forming swamps
fit only for the cultivation of rice. The extent of these swamps is
considerable; the tide rises high, and overflows great part of them;
but the intersection of the rivers renders them more pure than they
would otherwise be; and consequently the air is much healthier than one
could expect from the unfavourable aspect.”

In like manner Canton city he says “is built on a very extensive plain,
and is large and populous. Here the government allow the English,
Dutch, French, Danes and Swedes separate factories on the banks of the
river. The city, though paved, is very wet in rainy weather; and the
water makes its way under the factories of the different nations every
tide. The houses are built with bricks; the apartments are in general
small, and not very lofty, and the ground stories are very damp. When
the business of the season is over, the supercargoes remove to Macao,
a Portuguese island, subject to the Chinese government. The city of
Macao is situated on a rising ground; the whole island is dry, rocky
and barren; it is, however, plentifully supplied with provisions by
the Chinese; and, though the air is very sultry, yet it is tolerably
healthy.”

From the preceding account it is plain, that the causes which operate
in the production of plagues and epidemic diseases in other countries,
though they exist in China, do not act there with equal efficacy.
At Wampoa the marshes in the neighbourhood must, in the hot season,
emit noxious effluvia as well as any where else, and there can be no
certainty that the overflowing of the tide is sufficient to put a stop
to their malignant influence. At Canton the water penetrates below the
floors of the houses, and we have seen from Dr Fordyce[117] that _in
other countries_ the sprinkling of a floor with clean water, and the
encampment of an army upon ground where water was found at a small
depth below the surface, were sufficient to produce fevers; yet here
it is not so. In this city also the inhabitants are numerous, and the
apartments small; so that neither the perspiration of multitudes, nor
the moist exhalations from water stagnating in the streets, nay, under
the houses themselves, are able to produce the diseases in question.
Again, at Macao the sultry heat of the air has as little effect as the
rest.

  [117] See p.p. 171, 172.

Lastly, in Pekin, the capital, the population and the crowd are
immense. According to Sir George Staunton,[118] the city is about one
third larger than London; but, as he supposes[119] it to contain three
millions of inhabitants, the population must be twice and a third-part
as great as that of London in proportion to its bulk. “The low houses
of Pekin (says he) seem scarcely sufficient for so vast a population;
but very little room is occupied by a Chinese family, at least by
the middling and lower classes of life. In their houses there are no
superfluous apartments. A Chinese dwelling is generally surrounded by
a wall six or seven feet high. Within this enclosure, a whole family
of three generations, with all their respective wives and children,
will frequently be found. One small room is made to serve for the
individuals of each branch of the family, sleeping in different beds,
divided only by mats hanging from the ceiling. One common room is used
for eating.”

  [118] Authentic Account of an Embassy, &c. vol. ii, p. 54.

  [119] Ib. p. 39.

Where diseases are prevalent, circumstances of the kind just mentioned
would certainly be urged as evident _causes_ of them; but in China
we see that _something_ disarms such causes of their power. People,
however, seldom want a salvo for any thing. “The crowds of people,
at Pekin (says our author) do not prevent it from being healthy. The
Chinese indeed live much in the open air, increasing or diminishing the
quantity of their apparel according to the weather. The atmosphere is
dry, and does not engender putrid diseases; and excesses productive of
them are seldom committed.” But, if the dry air at Pekin contributes to
the health of the people, why does not the moist air of Canton produce
diseases? Besides, in this empire there are multitudes of people who
live entirely upon the water, in a kind of houses constructed upon
junks, employed in carrying grain from place to place, or for other
purposes.[120] Sir George Staunton computes the number of inhabitants
on a branch of a single river to be no less than an hundred thousand.
What then must they be throughout the whole empire! Yet these people,
though continually exposed to moisture, as well as to an almost
inconceivably crowded situation, are yet no more subject to epidemics
than others. Our author does not specify the _excesses_ which produce
disorders. Intemperance in drinking no doubt is one of them; but Dr.
Patrick Russel expressly says, that he never saw an instance of the
plague being brought on by intemperance.

  [120] Authentic Account, &c. vol. i, p. 290.

Lastly, with regard to living in the open air, Mr. McLean has ascribed
to the vicissitudes of this element the principal if not the _only_
cause of epidemics. “A fact worthy of notice (says he) is, that aged
persons and children are both seldomer and less severely attacked by
epidemics and pestilential disorders than the young and middle aged,
and women seldomer and less severely than men. Now, if contagion was
the source of these diseases, the case would be exactly reversed. Old
people, women and children, being more in the way of contagion, would
be more frequently and more severely attacked. But the young and middle
aged, being more exposed to the _vicissitudes of the atmosphere_,
the principal source of those diseases, they are consequently more
severely attacked. It has been a puzzling question to solve why old
people and children are less exposed to plague, &c. but the solution
will be no longer difficult if it should be proved that these diseases
are _always_ produced by certain states or vicissitudes of the
atmosphere, together with the application of other powers co-operating
in the production of indirect debility.” In the country we speak of,
however, this solution fails in a manner almost as evident as can be
imagined. “The removal of the embassy, (says Sir George Staunton)
was a disappointment to several persons belonging to it, who had
made arrangements for passing the winter at Pekin. Judging of its
temperature by the latitude of the place, a few minutes under 40°
north, they were not aware of the violent effect of the great range
of high Tartarian mountains, covered perpetually with snow, upon that
capital, where the average degree of the thermometer is under twenty
in the night during the winter months, and even in the day time is
considerably below the freezing point. The usual inhabitants were
guarded against cold, not only by habit, but by an increase of clothing
in proportion to its intenseness, consisting of furs, woollen clothes
and quilted cottons. They are not accustomed to the presence of fire.
They have no chimneys, except to kitchens in great hotels. Fires, on
which Englishmen chiefly depend against suffering by the sharpness of
the atmosphere, could not well answer that purpose in houses which
are so constructed as to admit the external air almost on every side.
Stoves are, however, common in large buildings. These stoves are
situated frequently under the platforms on which the inhabitants sit
in the day time, and rest at night. The worst weather experienced
in that capital might be considered as mild by the Tartars, coming
from a climate still more rude; but other foreigners are said to feel
themselves less comfortable at Pekin in the winter than in the summer,
though the heat is then raised to the opposite extreme. In both they
seem to require a seasoning. _Several individuals of the embassy fell
ill during their stay; and all did not recover._ The human frame seems
calculated for the hottest rather than the coldest atmosphere, and to
exist at the equator rather than the pole.”

Here we are involved in difficulties much greater than before. It
appears that even the fine climate of China is healthful only to its
own inhabitants. They can bear the _vicissitudes_ of the air, which
Europeans cannot. The prevention of plagues or mortal diseases then
must consist in some mode of living by which people can accommodate
themselves to the country which they inhabit, and without which every
other precaution will be ineffectual. The diseases with which the
attendants of the ambassador were seized could not be owing to any
slovenliness or dirtiness in their lodgings or food, or to want of
apparel; nor were they more exposed to the inclemencies of the air than
others; only they were in a strange country, where that inexplicable
constitution of the elements acted upon them in a manner different from
what it did on the natives, and, while it was friendly to the latter,
proved pernicious to the former. But there was a time when even China
was as unhealthy as other countries; for the great plague in 1346 began
in the northern part of it. We have seen, in a former section, that
this was preceded by the most dreadful and violent wars throughout the
whole Asiatic continent. Since the cessation of these violent wars
the Chinese have staid at home, and applied themselves to the arts of
peace, particularly to agriculture, which they have carried, we may
say, to its utmost perfection. This seems therefore to be the true
method of removing all those local causes which produce epidemics, or
at least of preventing them from doing hurt; and, without attention to
the natural duties and occupations of man, it is to be feared that all
artificial modes of prevention will be found not only precarious but
ineffectual.

Dr. Smith in the dissertation above mentioned observes, that “it may
be doubted whether any _moral_ cause would be sufficient to protect,
for a long period, an unaccustomed resident in a marshy situation from
the usual consequences.” This is no doubt very probable but, from the
example of Lord Macartney’s attendants in China, it appears equally
probable that it makes little difference whether the country be marshy
or not. Dr. Lind has many excellent observations upon the subject of
unhealthy countries, and gives particular directions for strangers how
to act, when obliged to expose themselves to the inclemencies of the
weather; but none of these being effectual in preventing the access
of the true pestilence, we must still adhere to the old Latin adage
already quoted, p. 302. Flight seems to be the most effectual method.
To avoid migrations to those countries where it usually rages, and,
if it were possible to persuade the inhabitants of such countries,
to imitate the example of Chinese industry, instead of allowing the
greater part of the territories they possess to lie waste, would in all
probability gradually lessen both the frequency and violence of this
terrible disease. Migrations of large bodies of people, especially for
the purposes of war, are greatly to be dreaded. If a few Englishmen,
possessed of every thing necessary, could not keep their health at
Pekin, what must have been the probable consequence of landing an
army of an hundred thousand, with a view to conquest? Or what could
we expect if the Chinese were to “pour forth by millions” into other
countries in order to conquer them? Dr. Lind takes notice that even
of the first Portuguese adventurers to Africa, such as escaped the
first sickness continued afterwards to enjoy good health. He likewise
observes that many who left Britain, after being seasoned to the
countries to which they went, chose rather to remain abroad for life,
than to run a new risk by going back to their own country. It is not
therefore so much the greater unhealthiness of the country to which we
go, as the _change_, which is to be dreaded. If therefore great bodies
of men will employ themselves in constant rambling from one country to
another, no wonder that diseases break out among them, unknown, either
in the countries they have left, or those to which they go.

We come now to the third mode of prevention, viz. that of destroying
the infection after it has begun to exist. This is varied according
to the nature of those things which we suppose to be infected. The
general notion of infection taking place in the atmosphere has been
already spoken of; but the uncertainty of this hypothesis, and the
apparent impossibility of altering a constitution of the atmosphere,
must certainly leave very little room for hope in this case. It hath,
however, been attempted by various methods. Hippocrates adopted the
opinion that all diseases were produced by the air, and from him it was
borrowed by Lucretius, as we are informed by the annotator on Creech’s
Translation of that author. “In his book _de Flatibus_ (of winds) says
the annotator, after a long narration of the effects that the air
produces, he at length falls on the subject of diseases, all of which
he affirms to be bred and generated in the bodies of animals by means
of the air. First (says he) I will begin with the most common fevorous
disease, which accompanies, in a manner, all diseases whatever. For
there are two sorts of fevers, one that is promiscuous, and common to
all, and is called the _plague_; the other, by reason of unhealthful
diet, is peculiar only to such as use that diet; but of both these
kinds of fevers the air is the sole author and cause, for the common
fever or plague happens alike to all, because they all breathe the same
air; and it is certain that the like air, being alike mingled in like
bodies, must beget like fevers.” In consequence of his theory, this
great physician advised to have recourse to fire as a purifier of air
in times of pestilence. But experience doth not warrant the success of
this method; neither indeed can we suppose that it could be successful,
unless people were able to kindle such fires as would absorb the whole
atmosphere of a country. This method was tried in London without the
least success; nay, seemingly with bad effect; for, the very night the
fires were lighted, more than four thousand people died; and, a few
days after, an end was put to the experiment by such violent rains as
extinguished all the fires at once.

The burning of infected clothes has already been taken notice of; but
though this must certainly prevent any new infection from arising from
_these_ clothes, it will not prove that the infection may not evaporate
during the time of burning, and, being volatilized even beyond its
natural pitch, by the heat, may do mischief at a greater distance than
could have happened had they been let alone. The instance, formerly
quoted from Dr. Huxham, of the small-pox being disseminated by the
smoke of burning infected clothes, if not a _proof_, affords at least a
strong presumption, of the danger of such a practice. The only way of
perfectly ensuring safety in such a case would be to burn them by the
sea-side, when the wind blows from the shore. Were the smoke allowed to
pass over land, and great piles burnt at once, it is impossible to say
how far the contagion might be carried.[121]

  [121] In the time of the great fire at London, in 1666, ashes are
  said to have been carried to sixteen miles distance.

Another mode of purification is by exposing suspected goods to heat,
to the vapour of vinegar, &c. fumigating with gun-powder, sulphur, &c.
and on this principle various powders of fumigation have been invented;
some of which are said to have been very successful in Russia; and the
composition of one is given by Dr. Alexander Russel in his Natural
History of Aleppo; but all these are undervalued by Dr. Guthrie,[122]
who calls the practice of fumigation or smoaking, an “inadequate and
ineffectual ceremony.” Dr. Mitchel, also discommends them, saying that
they are advised “without any proof that these destroy pestilential
matter, and while, at the same time, it is certain that they diminish
more or less the wholesomeness of the atmosphere with which they are
mingled.”[123] Of late the vapours of pure nitrous acid (the _nitric_,
according to the new nomenclature) has been recommended, with the
boldest appeal to experience; but the consideration of this naturally
belongs to the second part of this work, where we shall have occasion
also to consider the theory of the septic acid. In the mean time
we must go on with some farther account of the different modes of
fumigation.

  [122] Duncan’s Med. Comment. vol. viii p. 350.

  [123] Med. Repos. vol. ii, p. 433.

“There is no better corrective (says Allen from Diemerbroeck[124])
of a pestilential air, than fire; as much experience has taught us.
Hippocrates subdued and extinguished that famous plague, which came
amongst the Grecians from Ethiopia; for he commanded great fires to
be kindled throughout the whole city, especially in the night time,
to purge away the pollutions of the air. It is believed that a fire
made with juniper-wood or ash, tends much to correct the venomous
corruptions of the air. The kindling of sulphur and gun-powder purify
the air, and drive away its corruptions; so does the burning of amber,
pitch, frankincense, &c. so do the fumes of vinegar raised with red-hot
irons, or bricks.” According to Etmuller, “Hippocrates drove away _that
famous plague_ in Greece by the use of sulphur; the fumes of it are
very much commended to correct the air, and make drink more wholesome;
it prevents all manner of corruptions and alterations, as well as the
putridinous alteration of the blood. In a great degree of malignity,
the shirt and clothes may be impregnated with the fume of sulphur.”

  [124] Synopsis, vol. i, p. 80.

Here we have accounts of a disease, called _that famous plague_, driven
away by two different methods; and, to complete our dilemma, Dr.
Canestrinus tells us that the _plague at Athens_ is said to have been
staid “by sprinkling the streets with wine.” What an expensive remedy,
when the odour of _privies_ was afterwards found to answer as well!
“Whilst the plague was raging at Oczakow, an _earthquake_[125] happened
on the very day that it began to decline. In this case did any vapour
issue from the earth destructive of the pestilential contagion? or did
former noxious exhalations cease in consequence of the convulsion of
the earth?[126] Sorbait relates, that, in the time of the vintage in
the neighbourhood of Moselle, the plague ceased like a miracle, while
the must was in a fermenting state. At Vienna likewise it was observed
that, during and at the close of the vintage, the disease manifestly
declined; which may have been owing to the great quantity of fixed air
in the atmosphere.”

  [125] Earthquakes, as we have already seen, might be accounted
  rather a _sign_ or _cause_ of the beginning of pestilence, than of
  its departure. A great quantity of electricity in the atmosphere
  has accordingly been enumerated among the signs of an approaching
  pestilence. Thus in Burnet’s Thesaurus, p. 699, we find among the
  previous signs of a plague, “plurima et fere continua nocturna
  fulgora, sine pluviis et tonitruis, cœlo non nubiloso existante.”
  Very much and almost continual lightning at night, without rain or
  thunder; the sky in the mean time not being covered with clouds.

  [126] Before we can attach any degree of probability to either of
  these suppositions, it must be proved that plagues arise out of the
  earth. But this, though as plausible as many other hypotheses, is not
  yet supported by any direct proof.

To this our author adds, that “places adjoining to spice-shops have
generally remained free from infection; and, in the plague of London,
all those employed in shipbuilding escaped the disease. Smiths also
and cooks remained uninfected.” M. Volney tells us that, in Egypt,
water-carriers are exempted; and Baldwin, that oilmen are in the same
happy predicament; while on the other hand Allen quotes Boerhaave
saying, that “Forestus, Diemerbroeck, the French, English, and Germans,
observed, that all dealers in soap, washers, and all who by their
business used soap, nay, _who only wore shirts washed with soap_,
presently died of the plague.”

From so many and so discordant opinions, the only conclusion we can
draw is, that, when once a pestilence has invaded a country, there is
not any possibility of operating upon the contagion in such a manner as
to destroy it. If the plague ceases, it must do so naturally, and we
_cannot_ accelerate this cessation. This is entirely conformable to the
opinion of Dr. Patrick Russel. Speaking of the decline of the plague at
Marseilles, and the vigorous exertions of the magistrates to put a stop
to it, he says, “The causes now enumerated might no doubt have some
effect, but a more powerful and general cause had begun long before to
restrain the havock of the pestilence, which had declined visibly in
the month of September, and in those of October, November and December
declined with a rapidity not ascribable to the exertions of the most
vigorous police. This cause is generally supposed to be some change in
the constitution of the air; but which has hitherto been defined with
no better success than that peculiar state of the atmosphere which,
in conjunction with contagion, is absolutely necessary to render the
plague epidemical.”

Dr. Russel takes notice of the methods of extinguishing contagion
already mentioned, by kindling fires, &c. and disapproves of them.
We shall not therefore spend more time in considering whether or not
there is any probability of eradicating or mitigating the violence of
a plague when once it is introduced. However this may be impracticable
in so large a space, it seems that it certainly may be done in
smaller spaces, ships for instance; or, if not with the true plague,
at least with malignant and infectious fevers. Dr. Trotter, in his
Medicina Nautica, has laid down methods for accomplishing this, and
expresses the highest confidence in their success. He adopts the
doctrine of _contagion_, of which he gives the same definition that
in this treatise is given of _infection_, viz. “Something propagated
from diseased bodies, or from substances that have been in contact
with them, producing a similar disease in other persons[127]--the
propagation of contagion, as well as its reception into the healthy
body. A more aggravated degree of malignity will generate a greater
quantity of infection, and, as it may be confined in a larger or
smaller space, it will be less or more noxious. A fever may be called
malignant, when, with the symptoms of debility, there is a cadaverous
smell arising from the body, an unusual fœtor of the breath, stools,
and other excretions, the tongue black and parched, the eye dusky or
yellow, the countenance bloated and dejected, and the skin sallow.
In approaching a sick bed of this kind, a person not much accustomed
to such visits will be very liable to receive the infection; and the
unpleasant smell will be much sooner perceived than by the physician
or other attendants. We conclude that a malignant typhus is more apt
to generate contagion, because slight cases are found not to extend to
others, even though no mode of precaution has been used. The disease
itself is incapable of generating infection, till after a certain
period; but this period is uncertain: it seems to depend on the
nature of the symptoms, whether they are mild or malignant. _We are
assured of this fact, from a timely separation having prevented the
farther progress; and by this means_ ALONE, _I apprehend, we eradicate
contagion in_ SHIPS, _or_ ANY WHERE ELSE. In the small-pox[128] the
disease seems incapable of infecting another person before the second
or third day of the eruption. With the measles it is otherwise. The
disease may be propagated at the most early stage of the eruption; and,
if I was to be allowed to conjecture on the subject, I would say, that
the contagion is the offspring of the catarrh (the cough and hoarseness
resembling a cold) which accompanies the measles.

  [127] Medicina Nautica, p. 173, _et seq._

  [128] In the plague, Dr. Russel has observed, that those who die in
  a very short time are much less ready to communicate infection, than
  those who live longer. He also takes notice, that “the plague, though
  a contagious disease, is not equally contagious in every period of
  the pestilential season. In the beginning those frequenting the sick
  often escape unhurt, or one only, out of several, is infected. The
  escape of persons employed about the sick, proves a frequent cause
  of misleading the popular opinion of the disease, and has in many
  instances occasioned much mischief, by encouraging the neglect of due
  precautions till too late.”

“Substances imbued with the exhalations from infected bodies, if not
exposed to the air, have their powers of communicating the disease
increased; or, in other words, the infection from _fomites_ (infected
cotton, clothes, &c.) is said to become more virulent than it was when
first separated from the body.

“I am of opinion, with others, that the exhalations or excretions of
the sick are the vehicles of contagion. It is these which impregnate
the atmosphere with noxious matter: they affect in like manner
bed-clothes, or apparel, and every thing that can imbibe them, when
in contact with the diseased body. When bed-clothes, or body-linen,
but particularly silk or woolen cloth, have been exposed to these
exhalations, and then heaped together for a length of time, the noxious
effluvia are, as it were, multiplied, and will more certainly infect
others than they did at first. The bales of goods which brought the
plague to Marseilles, and affected the people that opened them so
suddenly, had their virulence increased by not being duly ventilated.
When the jail-fever was brought into court by the prisoners at Oxford
assizes, and more lately at the Old Bailey, the fever was propagated
from the clothing of the prisoners; no doubt, from being confined in
impure, ill-aired cells, this infection became more virulent. The
highly concentrated state of contagion, in the bales of goods, could
only have been brought to that degree of virulence from the closeness
of the package: it cannot be supposed that human beings could have put
them together otherwise. The nurses of hospitals know well, as Dr. Lind
tells us, that there is most danger of catching a fever when they pile
heaps of bed-clothes or body-linen together for a few days, before it
is carried to the wash-house. The washer-women at Haslar have also told
me the same thing. They know when a dangerous fever is in the hospital
by the bad smell of the clothes: this makes them air them abroad, till
the smell is gone, and then they can wash them with safety. But, if it
happened, from the hurry, that this could not be done, or if it was
neglected by design, many of them were seized with the sickness. The
porters and people employed in cleaning and fumigating the blankets and
beds at Haslar are well acquainted with this fact, and they measure
the danger by the badness of the smell. This ought to instruct every
body to stand to windward of these infected substances when they are
opened; as the current of air would then carry it the other way. In one
of the courts of justice, the people who stood between the prisoners
and a window, into which the wind blew, escaped the infection, while
those on the other side were sufferers.

“In the summer of 1793, while the Orestes brig, commanded by Lord
Augustus Fitzroy, lay at Plymouth, she was anchored very near and to
leeward of an army transport, which had on board a very malignant
fever among the soldiers. While the soldiers were moved on deck, to
go on shore to the hospital, the crew of the Orestes, from curiosity,
walked on deck to look at them. Such was the concentrated state of
the contagion among the clothing and bedding of these troops, on
bringing them from below, that eighteen people belonging to the brig
were quickly seized with the same fever, the infection of which had
been conveyed by the current of wind. It did not, however, extend much
farther in the Orestes, from the attention of her commander. But this
ought to be a caution for ships to keep clear of those that have fevers
on board, as a _virulent_ CONTAGION _may be conveyed to a considerable
distance_.

“Dr. Lind is inclined to think that washing the bed-linen in hot water,
even when first shifted, is attended with much risk; and that the
noxious matter may be volatilized by the heat of the water, and affect
the woman. For this purpose he has recourse to his favourite process,
of _fumigation_, to insure the washer-woman. The heat of his fumigating
furnace would no doubt dry the linen, and exhale any moisture; but our
practice in the Charon (the hospital ship) was, to plunge everything as
it came from the bed into a tub of hot water kept ready on purpose. The
linen was washed and dried immediately after. We had in that hospital
many malignant cases of typhus, and some deaths, yet no infection was
ever spread there.”

Our author next proceeds to inquire into the cause of this excessive
concentration of the infectious matter in _fomites_, or clothes,
bed-clothes, bale-goods, &c. The most plausible reason, he says,
that could for some time be assigned for this, “was, the generation
of animalcula; the cotton or woollen clothing was said to serve as
a nest for the corpuscles to multiply; and thus the contagion was
thought to increase seven fold.” This theory had an effect on the
practice of physicians, both as to the prevention and cure of fevers
supposed to proceed from thence. Our author looks upon the hypothesis
to be chimerical, because none of these animalcules have ever been
made visible by the best microscopes. But there is no necessity for
supposing the animalcules to be invisible to the naked eye. They may
creep on the ground, or fly in the air, without being observed by us.
Mr. Baker’s discovery of the insect which not only poisoned _eleven
hundred thousand_ times its bulk of water, but infected a much greater
bulk of air, with its effluvia,[129] shows that such a thing may be
_possible_; and in dubious matters bare possibility ought always to
produce inquiry. If the perspiration of human bodies when confined
becomes noxious, why may not that of a multitude of insects be so too?
There is no necessity for supposing that an insect must be swallowed,
or inhaled by the breath, before it can do hurt. What Dr. Trotter says
of the variolous contagion emitted from the human body will apply
equally to insects. “What has been called the insensible perspiration
(says he) which arises from the surface and the lungs, we have a right
to believe carries with it in solution a portion of the variolous
matter which charges the atmosphere with the contagion of small-pox,
even in such quantities as to impregnate the clothing of attendants and
visitors; by which means it has been frequently carried to families and
villages many miles distant from its source.” The smallness of size of
insects can be little objection here. A skunk is but a small animal,
yet it spreads its odour farther than an hundred diseased human bodies
could propagate the plague.[130]

  [129] P. 189.

  [130] Here, I hope, it will not be thought unreasonable to digress a
  little in favour of the sensations of humanity which on all occasions
  ought to predominate in our minds. Birds are the natural enemies of
  that hateful class of beings we call _insects_, and which in general
  are the natural enemies of man. In proportion to the havock we
  make among the former, the latter will multiply upon us whether we
  will or not. The wanton, indiscriminate, and I may add _provoking_
  destruction exercised among this useful as well as beautiful and
  agreeable part of the creation, must certainly be sometimes attended
  with bad consequences. Though birds feed on many different kinds of
  insects, yet there are exceptions. If then we totally exterminate
  a species of birds, is it not probable that a species of insects
  might appear, the mischief done by which we could not be able to
  counteract? _Quere._ Is it not possible that the _Hessian fly_ may
  have made its appearance from this cause?

On this subject, however, we may remark, that though the nurses and
attendants on hospitals measure the degree of infection by the smell,
yet people are by no means safe in approaching patients about whom no
smell can be perceived. We have already seen, from Dr. Fordyce, that
what may be called the _pure_ infection of fevers is not perceptible
by any of our senses; and there are examples of very offensive smells
issuing from diseased bodies without any contagion ensuing. Dr. Trotter
tells us, that “a patient in typhus was sent from the Venerable to the
hospital ship, with a fœtor about him, that exceeded any thing of the
kind that ever came within the Doctor’s knowledge. After being washed
and shifted, it still continued, and was perceived at a considerable
distance. He died in a few days, yet nobody was infected from him,
either in his own ship, or in our hospital. There was probably some
peculiarity of constitution here.” In M. Deidier’s experiments, above
related, the dog which eat the dressings of the plague sores, after
being infected with the disease, emitted a very disagreeable odour,
but we do not find that the odour was in any way infectious. In the
Encycloped. Britan, art. Med. _Hydrophobia_, we find an account of an
hydrophobic patient (and a patient who recovered) in whom the blood
drawn from a vein was as black as ink, and stunk abominably, yet
this stench was attended with no bad consequence. There is therefore
no essential connexion between offensive smells and contagion; yet,
as they are sometimes united, the absence of the smell ought not to
encourage us rashly to go into suspicious places, neither ought the
presence of it to deter us from venturing where we have otherwise good
reason to do so.

Having given up the doctrine of animalcula, the Doctor goes on to
explain the doctrine of concentrated contagion in a manner very
similar to that given in this treatise, viz. from the decomposition
of some kind of gas. “The fœtor of the breath (says he) perspirable
matter, &c. evidently demonstrate that they differ from the healthy
state. The smell, to our senses, comes very near what is called
_sulphurated-hydrogenous gas_. Some of the fluids within the body would
seem to be in some degree in a state of actual decomposition; unless
we can suppose the mucous glands of the lungs secreting a fluid that
taints the expired air in this manner. The decomposition of the fat,
which sometimes disappears very suddenly in fevers, may give some
ground for the supposition that a large portion of these exhalations
are composed of hydrogenous gas. But, whether we can go thus far or
not, what is separated from the body, it is plain, is more disposed
to decomposition than when the body is in health. Now this process
will still go on, whether exposed to the atmosphere or not, with
this difference, that, by exposing substances which have imbibed the
exhalations of the diseased to a free air, the noxious gases will be
dissipated as quickly as they are evolved; while, on the other hand, by
laying the clothes in a heap, packing them firm in a chest, or making
up cloth into small bales, the gases are concentrated into a small
space; and woe to the man who first inspires them.... Now this does not
hold out an idea that the powers of contagion are multiplied, as by
generation; for that would be to say, that these gases are _themselves_
what we call the matter of infection. I would only go so far as to
assert that they are the vehicles of it, till more certain experience
shall determine farther.”

With respect to fumigations with nitrous acid, our author repeatedly
declares that he has no confidence in them; nay, he brings instances
where they seemed to have bad effects. But as the dispute about
fumigation has no connexion with the true plague, nitrous acid having
never been used as a preventive for it, we shall defer any farther
consideration of it to the second part of this treatise, to which it
naturally belongs.

We come now to the fourth and last mode of prevention, viz. a
consideration of those means by which an individual, without separating
himself from society, and who is daily obliged to have communication
with the sick, may yet secure himself against infection. Here the
means recommended are extremely various, and some of them so opposite,
that we can scarce avoid suspecting them all. The misfortune is, that
though a person should go, without fear, among the sick, though he
should constantly take a medicine, and should never have the distemper,
yet we cannot say whether the medicine did preserve him or not. Were
it possible to know the particular constitution of the body which
disposed some to resist the attack of the disease, attempts might be
made to bring the constitutions of others to the same standard, but
unfortunately our ignorance here is so great, that any attempt to
alter the constitution of the body has generally proved unfortunate
even in other diseases. Dr. Lind informs us, that the first Portuguese
adventurers in Africa, having observed, that “such as had the good
fortune to escape a fit of sickness or death, soon after their arrival,
enjoyed afterwards a pretty good state of health, thence concluded,
that the blood of such persons had been entirely changed by the diet
of the country. Upon this erroneous principle they adopted a most
fatal method of seasoning people to these unhealthy climates. They,
by small quantities, frequently repeated, took away as much blood
as they supposed to be contained in the body, and thus they reduced
the patient to a state of extreme weakness.” From its being observed
that people of delicate constitutions are less liable to the plague
than others, such a mistake probably has also been made with regard
to this distemper, but with equally bad success. Allen tells us from
Diemerbroeck, “_Phlebotomy_, though mightily cried up by many of the
ancient and modern physicians, yet we reject it altogether, _as very
dangerous and detrimental_; for it appeared by experience that those
who made use of it for prevention’s sake were seized with the plague
soon after bleeding, wherefore we forbad it to all.” This may seem
surprising, as we find bleeding so much recommended by Sydenham as a
remedy; but by others it is equally reprobated; nay, Dr. Hodges tells
us that he never knew but one who recovered from the disease after the
use of it. Issues seem more likely, if not to prevent, at least to
render the disease more mild if it should attack. They are recommended
by Diemerbroeck, and Russel speaks of them as, “by some authors,
represented as almost infallible.” He cannot, however, recommend them
from his own experience, having never seen them opened for the purpose
of preventing the plague; and he justly observes, that when habitual
on any other account, they may perhaps lose their effect in this.
“Multitudes (says he) of both sexes at Aleppo had issues in their arms,
it being there a very common remedy in a variety of chronic disorders:
but, notwithstanding those outlets, numbers perished; and I did not
remark that those who had them were in any degree less liable than
others to be infected.”

Tobacco has been recommended as an excellent preservative, particularly
by Diemerbroeck, who writes with a kind of enthusiasm in its favour.
“Being called (said he) to visit a patient afflicted with the plague,
as soon as I entered his chamber I felt a most offensive smell of
excrements (for he had a diarrhœa) with which I was greatly affected.
Leaving the house after a very short visit, I instantly found myself
seized with giddiness, nausea, and uneasiness at the heart; so that I
had no doubt of my having caught the pestilential contagion. Laying
aside all business, therefore, I immediately returned home, and smoked
five or six pipes of the best tobacco; by the use of which all the
above-mentioned symptoms so totally vanished, that I felt not the
least uneasiness any more. Then, being again desirous to go abroad
and visit other sick people, I took a drachm of theriaca, and from
thence-forward was in perfect health. The same thing happened to me
three or four times during the time of this pestilence; and without
loss of time, according to the quantity of infection I supposed that
I had taken in, I had recourse to the more plentiful use of tobacco,
by which my health was restored. I always looked upon tobacco to be
an excellent preventive remedy, and its smoke I have sometimes found
useful to myself even in an incipient attack of the disease.[131]” He
then proceeds to inform us of a report that in a violent plague at
London all the dealers in tobacco were exempted. At Nimeguen, however,
they were not so fortunate; yet of the family of the principal tobacco
merchant (Thomas Peters, an Englishman) which was very large, none were
infected, excepting only one servant maid, and she quickly recovered.

  [131] Diemerbroeck, Hist. 17, lib. 4.

On this remedy Dr. Russel makes the same remark as on the issues. “The
custom of smoking (says he), is universal among both men and women at
Aleppo. This too, from its being habitually practised, might perhaps
lose part of its prophylactic virtue: at the same time those who use it
as a preservative must always be supposed in some degree accustomed to
it, otherwise the violence of its operation on most persons, on their
first beginning to smoke, might prove hurtful. It should further be
observed, that the tobacco commonly used in Syria is much milder than
the American, and that the oriental smokers seldom or never spit.”

It hath been observed that the plague is stopped either by great heat
or great cold, but more readily by the former than the latter. “It has
generally been supposed (says Dr. Canestrinus) that the cold of winter
was destructive of contagious matter; but various instances of the
contrary may be collected. The plague in Transylvania continued through
the very severe frost in 1709. On the contrary it has been found, that
excessive heat has extinguished, or at least diminished, pestilential
diseases. During the plague at Aleppo the weather was unusually hot in
the beginning of July, and it was remarked that the disease declined
considerably; and in general Dr. Russel observed, that the plague
ceased at the hottest season of the year. The plague at Ockzacow,
which raged in the years 1738 and 1739, began in the month of April,
and continued with violence till July, when it declined considerably,
and entirely ceased in the month of September; in February of the year
following it re-appeared, and totally ceased in July.”

From these facts we might be led to suppose that a warm regimen, or
occasionally exposing the body to great heat, might be advantageously
used by way of prevention; but Dr. Russel justly observes, that the
human frame, “could it support such an application of fire and smoke as
is necessary to expel or destroy contagion from infected substances,
would probably receive little benefit from it, if infected; nor could
those in health sustain, without prejudice, the heat and dense smoke
which is probably required for the perfect extinction of the infectious
effluvia floating in the confined atmosphere of a morbid body.” He is
of opinion, however, that some kinds of fumigations may be of use,
and he mentions some of these, but says that the perfumes ordered by
the college are perhaps as proper as any, though their forms might be
rendered more simple. Heat alone can scarce be thought very proper
for prevention, and, when the disease is once begun, is said to be
detrimental. Dr. Guthrie quotes Baron Ash saying, that “in heated
rooms the disease is ungovernable: it is only in free air that it is
to be treated.” But of late a discovery has been made of a surprising
power in heated oil of removing this disease, insomuch that, if we
can believe what has been published of it, we must suppose it to be
little less than a specific. So great indeed has been the confidence
put in this method, that, by order of the Academy of Sciences at
Lisbon, it has been translated into Arabic, French and Portuguese.[132]
“The method was first proposed by George Baldwin esq. agent for his
Britannic Majesty, and consul-general at Alexandria. He communicated
his method to Lewis de Pavia, chaplain and agent to St. Anthony’s
Hospital at Smyrna; who, after five years experience, pronounces it to
be the most effectual remedy hitherto made use of in the hospital of
which he has had the management for twenty-seven years. Immediately
after a person is perceived to be infected with the plague, he must
be taken into a close room; and, over a brazier of hot coals, with a
clean sponge, dipped in warm olive oil, his body must be very briskly
rubbed all over; for the purpose of producing a profuse sweat. During
the friction, sugar and juniper berries must be burned in the fire,
which raise a dense and hot smoke, that contributes to the effect. The
friction ought not to be continued more than four minutes, and a pint
of oil is enough to be used at each time. In general the first rubbing
is attended by a very copious perspiration; but, should it fail of this
effect, the operation may be repeated, first wiping the body with a
warm, dry cloth; and, in order to promote perspiration still farther,
the patient may take any warm sudorific drink, such as elder-flower
water, tea, &c. It is not necessary to touch the eyes; and other tender
parts of the body must be touched gently. Every possible precaution
must be made use of to prevent the patient from taking cold, nor must
the linen be changed till the perspiration has entirely subsided. The
operation should be repeated once a day, until evident symptoms of
recovery begin to appear. If there are already tumours on the body,
they should be gently and more frequently rubbed, till they appear to
be in a state of suppuration, when they may be dressed with the usual
plasters. The operation ought to be begun on the first appearance of
the symptoms of disease; if neglected till the nerves and the mass of
blood are affected, or a diarrhœa has commenced, little hopes can be
entertained of a cure; but still the patient should not be despaired
of, as, by an assiduous application of the means proposed, some few
have recovered, even after diarrhœa had commenced. During the first
four or five days the patient must observe a very abstemious diet; the
author allows only a small quantity of vermicelli, simply boiled in
water. Nor must any thing be taken for thirty or forty days, except
very light food, as, he says, an indigestion in any state of the
disorder might be dangerous. He does not allow the use of wine till
forty days. There is no instance of the person rubbing a patient having
taken the infection. He should previously anoint himself all over with
oil, and must avoid receiving the infected person’s breath into his
mouth or nostrils. The precaution to be used in all circumstances is
that of carefully anointing the body, and living upon light and easily
digestible food. Mr. Baldwin observes, that among upwards of a million
of people carried off by the plague in Upper and Lower Egypt, in the
space of four years, he could not discover a single oilman, or dealer
in oil.” _Lisbon, July, 1797. By Royal Permission._

  [132] Annals of Medicine for 1797, p. 373.

With regard to diet, and the use of spiritous liquors, opinions, as may
well be imagined, have been very discordant. Allen quotes Diemerbroeck
advising _poor people_ to take two or three spoonfuls of the best
white wine vinegar every morning, which he looked upon to be one of
the best preservatives: he recommends also the frequent application to
the nostrils of a spunge dipped in _treacle vinegar_. With regard to
himself he says that his principal care was to avoid uneasy passions of
the mind; and that when he found himself any way disturbed by these, he
cheered his heart by three or four glasses of wine: his common drink
was beer, and also white wine, small, or moderately strong, which
sometimes he drank to cheerfulness, but never to drunkenness. Dr.
Patrick Russel also says, that “a glass of generous wine, or any other
cordial more agreeable to the choice, may be taken before dinner, in
case of languor, or oppression at the stomach, from fatigue, fœtor,
or apprehension. _I found a rummer of old hock very agreeable on such
occasions._” Allen goes on to inform us from Diemerbroeck, that,
“as to diet, it is advisable in a pestilential disposition to use
temperance, which very much contributes to the preservation of health;
but all sudden changes are dangerous; wherefore it is most dangerous
suddenly to alter the usual rule of diet. It is very ill in the plague
to go abroad with an empty stomach: hog’s flesh is looked upon to be
very pernicious: all sweet things are to be avoided: wine moderately
made use of is good, but the abuse of it very dangerous.--Mercurialis
testifies, that among the Patavians and Venetians, most of the tipplers
died, who thought to drive out the plague with strong wines.” Mr.
Howard informs us, that a person in high station at Constantinople,
attributed his recovery entirely to the use of _green tea_, others to
_brandy_. He also mentions a Mr. Hare, master of a merchant vessel at
Senegal, who, during the prevalence of a malignant fever there, was
very much exposed to the infection, and who out of humanity waited
upon a negro, whom nobody would go near. He took no medicines, neither
did he taste either spiritous or fermented liquors, and was the _only_
European that entirely escaped the contagion.[133]

  [133] The opinion of those physicians whom Mr. Howard consulted upon
  this subject are given at large in the APPENDIX.

These accounts seem to evince that little or nothing is to be expected
from a change of diet. This is an attempt to change the constitution
of the body, and cannot be expected to succeed any more than bleeding.
There is a certain quantity, and a certain species, both of food and
drink, different in different persons, necessary to preserve health,
and those who require both in larger quantity or better quality than
others, are no more to be charged with intemperance than those who are
supported by the smallest quantity of the coarsest fare. In times of
danger, therefore, those who have been accustomed to spiritous liquors
ought not to give them over; neither ought those to begin the use of
them who have not used them before. From the account formerly given
of the structure of the human body, it appears to be furnished with
an apparatus for _exhaling_ or throwing out a perspirable matter as
well as for _inhaling_ or taking in one equally subtile. How far the
skin may be able to _inhale_ or rather _imbibe_ surrounding effluvia,
may be doubted; but with the lungs there cannot be any doubt; and
the effluvia taken into them must unquestionably affect the blood,
and of consequence the vital principle, almost without any medium.
To deprive the body of its due portion of nourishment therefore is
to _throw a temptation in its way_ (if I may use the expression) to
absorb _any thing_; and the same effect must ensue from any other mode
of debilitating it, either by intemperance, terror, or the like; and
hence to visit infected places while under any such debility must be
very imprudent. Dr. Russel agrees that it is a general and rational
precept, never to go abroad fasting. For those who cannot easily bear
fatigue without eating between breakfast and dinner, some light food
may be proper, at an intermediate hour, in order to avoid going into
the chambers of the sick with an empty stomach in the forenoon. “In
such circumstances (says he) after a long and fatiguing morning, I
have often found myself disagreeably affected in my latter visits, and
have been sensible of slight giddiness, and of the appetite flagging
at dinner, as if something lay on the stomach. I have known others
much more strongly affected in this manner, and consequently much
more alarmed. In such cases much no doubt may depend on the fancy;
but in those times the power of the imagination requires management.
So intimately is it connected with the accidental state of the body,
that the same risk, from which a man shrinks in a state of languor and
fatigue, he will encounter undauntedly after a temperate meal: the
strange, unusual sensations, which amount almost to a persuasion of
having caught the infection, will often, like the phantoms of a vision,
vanish after a few glasses of wine.[134] Whether any slight degree
of real infection can be thus dissipated, I shall not take upon me to
determine; it is sufficient for the present purpose to indicate the
means of restraining those alarming sensations which, when aggravated
by imagination, are apt to depress the spirits, and, according to the
general opinion, to reduce the human body to that _relaxed_, _inhaling_
state peculiarly susceptible of contagion.”

  [134] This _doctrine_ of _fancy_, or _imagination_, ought
  undoubtedly, as Dr. Russel says of the imagination itself, to be
  under some management. The indiscriminate use of the word has been
  carried to such a length as in a manner to supersede all evidence,
  testimony, argumentation or reason. With some it is sufficient to
  discredit the most positive testimony (even upon oath) if they take
  it into their heads that such a thing _cannot be_: which by the
  bye is as strong an evidence of _ignorance_ as any man can give.
  If imagination is given as a _cause_, the extent and nature of
  its powers ought to be ascertained; but who has done this? On the
  contrary I may say that not one in five hundred who makes use of
  the word would be able to define it. But the most curious mode of
  reasoning used by these _imaginary_ gentlemen is, if they are asked,
  “How do you prove that such a thing is the effect of imagination?”
  they are ready to answer, “I can indeed bring no proof that it is so,
  but how do you prove that it is not?” Here the _imaginaries_ have
  not _reason_ sufficient to show them that _they_ ought to bring a
  proof, and not those who say they saw or felt any thing. But, waving
  this, _sense_ is the highest faculty in our nature; _imagination_ as
  well as _reason_ are inferior to it; because neither the one nor the
  other can be conversant except about the objects of sense. If any
  person therefore says that he _sees_ or that he _feels_ any thing,
  nobody can, with any shadow of reason, say that he neither _saw_ nor
  _felt_ any thing. If one man sees what another cannot see, while the
  supposed object is easily within reach of the eyes of either, then
  the one who cannot see it has a right to suspect that the object
  is imaginary; but, if the person himself feels any slight pain or
  uneasiness, and that should go off in a short time, after drinking
  a glass of wine, there is as little reason to suppose that the pain
  was imaginary, as that the drinking of the wine was imaginary. In
  Dr. Russel’s case, though his strength was in general sufficient
  to resist the contagion in which he was immersed, yet, when that
  strength began to decay, it was no wonder that he found the contagion
  beginning to invade: a few glasses of wine gave vigour to the system,
  and enabled it to repel the attack. Had he been much fatigued with
  bodily labour, and found himself greatly relieved by a few glasses of
  wine, surely he would not suppose that his former fatigue was merely
  imaginary. Just so must it be in the former case; the one has no more
  to do with imagination than the other.

As to other modes of precaution, the Doctor advises that such as are
about the sick “should guard the mouth and nostrils with vinegar, avoid
drawing in the breath while close to the bed side, or swallowing their
spittle while in the infected chamber. Before they approach the bed in
order to examine the eruptions, the bed-clothes ought to be removed,
to give time for the dispersion of a confined steam which immediately
discovers itself to the senses; and it will be advisable to dip the
hands in vinegar before examining the parts. On coming out of the
chamber it will also be proper to rinse the mouth, and wash the hands,
with vinegar, plain or camphorated.” He advises also to fumigate the
clothes with nitre, sulphur, and juniper berries, burnt on a red-hot
iron.

“Upon returning home it may be advisable to shift clothes immediately,
hanging those taken off upon lines in a small chamber, to be again
smoked, and afterwards aired. The mouth and hands ought once more to be
well washed, and the hair might be fumigated with a little nitre and
sulphur, by means of a pipe, so as not to incommode the lungs.”

One other mode of prevention, not of the disease, but of incurring
danger from it, is inoculation. This is greatly recommended by Baron
Ash above mentioned, and not only for the plague among the human
species, but for that among cattle, which frequently destroys great
numbers of those necessary animals. The case of Mathias Degio related
p. 272, shows the practicability and the safety of it. The only solid
objection that can be made to it is, that those who have once had the
plague are not secure from having it a second time, or oftener. Yet, if
we consider the extreme fatality of the disease when it attacks in the
natural way, and that the number of those who have the plague only once
is much greater than of those who relapse, this practice will certainly
be found to merit consideration, and, unless some objection to it be
discovered greater than any that has yet appeared, seems likely to be
advantageous to the human race in general.



SECTION V.

_Of the Cure of the Plague._


From what has already been laid down in a former section concerning
the nature of this distemper, it appears, in its worst and most
deadly form, to consist in the sudden breaking forth of a kind of
hard mortifications, or rather eschars, like those made by fire, in
different parts of the body. When these happen to fall upon any of
the vital parts, it is evident that no cure can be applied. When such
eschars discover themselves in abundance on the external parts, it is
likewise observed that the patient certainly dies; whether from the
same taking place inwardly, or from nature not being able to bear the
loss of substance, and to separate so many deep eschars, is uncertain:
but this kind, which attacks without fever, has always been reckoned
absolutely incurable. When the tendency to internal mortification
is less, and the fiery blasts, if we may so call them, approach the
surface, so that buboes or carbuncles begin to appear, there is
then some hope that the patient may recover. Even here, however,
the case must be considered as very doubtful, and we have seen that
in Dr. Russel’s three first classes of patients not one recovered;
nevertheless, as we are not always able to distinguish with certainty
whether the patient is altogether beyond the power of medicine or not,
excepting where the _tokens_ formerly mentioned appear, this kind only
is here distinguished by the name of the _fatal_ or inevitably mortal
kind of plague. In all cases, where there is time allowed, medicine
ought to be employed; but, as in other diseases, different theories
have bred such a contradiction of opinions, that it is with no small
difficulty we can judge which has any _probability_ of success. In
this uncertainty, however, we must look upon those who have recently
had an opportunity of seeing the disease as superior not only to those
who have only _read_ of it, but even to the most celebrated ancient
physicians who have written upon the subject. Those who have had
the best and latest opportunities of seeing the distemper are Drs.
Alexander and Patrick Russel at Aleppo, and the physicians to the
Russian army when the plague raged in it in 1770, &c.

Dr. Alexander Russel begins with observing that “the discordant
opinions of medical writers concerning the method of treating the
plague are innumerable. In regard to bleeding and other evacuations,
they maintain opinions diametrically opposite; some recommending
them as indispensably requisite, others decrying them as invariably
pernicious; while both parties, with equal confidence, appeal to
experience. But, in a disease wherein reason is often perplexed, and
experience itself fallacious, it is greatly to be lamented that nature
is not more, and opinion less, consulted.

“No traces of any satisfactory method of cure are to be met with among
the natives at Aleppo. The Mahommedans, holding the plague to be a
penal curse inflicted by Almighty God on a sinful people, have less
faith in the efficacy of medicine in that disease than any other: and,
as the chief of those who practise physic are either Christians or
Jews, not armed with the doctrine of predestination, and consequently
apprehensive of contracting the infection, they (the physicians)
endeavour to confirm the vulgar notion of the inutility of their art
in the plague, with a prudential view of evading the danger of being
forced to visit the sick. Hence the greatest part of the infected are
either left to struggle with the disease without any assistance from
medicine, or are under the necessity of submitting to the direction of
the meanest and most ignorant of mankind.”

The whole practice of the native physicians consists in bleeding, let
the stage of the distemper be what it will, and afterwards attempting
to raise a sweat with the insignificant remedy of a few grains of
bezoar mixed with the distilled water of scorzonera. On the subject of
evacuations our author remarks, that bleeding, even very plentifully,
was always useful in the beginning, but as constantly prejudicial after
the first day. Vomiting was equally useful at the same period; with
mere warm water, if that would answer the purpose, but if not, small
drops of ipecucuanha or sal vitrioli might be added. Violent cathartics
were hurtful, but an emollient clyster or laxative of manna and cream
of tartar were not only safe but serviceable. “On the second day of
the disease (says the Doctor) where the remissions of the symptoms
were tolerably distinct, I have frequently and successfully given an
infusion of senna with manna and cream of tartar; and it is a fact
confirmed to me by repeated experience, that a purgative of this
lenient kind, given after the critical sweat, was the most effectual
means of promoting the suppuration of the buboes.

“The natural crisis of the disease was always by the skin. When a
copious sweat could be procured by art, it was likewise of service;
but the attempt, if made the first day, was attended with two material
inconveniences: the first, that the common diaphoretic medicines, if
given in the usual dose, if they failed in their operation, threw
the patient into a flame, and greatly augmented all their symptoms;
the second, that, though they produced the desired effect, it was
necessary to keep up the sweat a much longer time than most people
of that country could be persuaded to endure; and, if the sweat was
prematurely checked by exposure to the air, all the symptoms were
either exasperated, or (what was often the case) a diarrhœa was
induced, which, though at first it might seem to relieve, yet generally
proved fatal in the end.”

Contrayerva and valerian, saffron, the compound powder of contrayerva
of the Edinburgh College, are recommended as sudorifics; given in
small doses every four hours, with acidulated diluent drinks. These
medicines were occasionally joined with anodynes, among which syrup of
poppies was reckoned preferable to opium. In cases of diarrhœa, Venice
treacle or diascordium were joined with the diaphoretics. Neither bark
nor snakeroot could have a fair trial, on account of the prejudices
of the people: and on this occasion our author observes, that “the
physician who would obtain a ready compliance with his directions, in
that country, must as seldom as possible offend the palates of his
patients with nauseous remedies; for, whatever may be the consequence,
they will often rather choose to incur distant though great risks, than
avoid them by submitting to present inconveniences.” Nitrous medicines
were found ineligible on various accounts: 1. They did not, as in other
diseases, allay heat. 2. The sick could not bear them in ordinary
doses without languor and dejection. 3. They were apt to bring on a
diarrhœa.--The following is an epitome of our author’s practice:

1. Bleeding from ten to twenty ounces as soon as possible after the
seizure. The quantity seldom exceeded sixteen ounces, and even this is
greatly above what is taken in any other disease in that country.

2. After bleeding, where the nausea was considerable, the stomach was
cleansed with warm water; or, if that failed, with ipecucuanha or salt
of vitriol. It was of such importance to have both these evacuations
performed early, that our author instructed most of his acquaintance
how to act if they should be infected.

3. A gentle anodyne succeeded the vomit. If by it the stomach was not
quieted, an ounce of diascordium, or 15 drops of laudanum, were added
to the saline draught of Riverius.

4. Small doses of cordial and diaphoretic medicines, with a very small
quantity of antimoniated nitre, were exhibited every four hours; the
sick were encouraged to drink freely of a decoction of scorzonera
roots and barley, or spring water moderately acidulated with spirit of
vitriol. A mixture of the acid with syrup of violets was kept ready to
be added to plain water. All the drink was given warm if the patient
would be prevailed upon to take it so.

5. In the winter the sick were removed into more airy lodgings than
those in which they usually slept, and the air of the room was warmed
or corrected by a moderate fire. In summer only the windows opposite to
the patient’s bed were ordered to be shut; but even this restriction
was not universally complied with; many insisting upon setting all the
windows open in the day time, and sleeping on the house top at night.

6. In case of faintness and uneasiness, a cordial, composed of some
of the simple distilled waters, tinctures of saffron and valerian,
alkermes, and spirit of vitriol, was used with advantage and great
refreshment to the sick. This with plenty of acidulated drinks was the
chief prescription for infected children.

Under the above treatment, a sweat often broke out on the second or
beginning of the third day; after which the sick were covered up, and
the sweat encouraged as long as they could be persuaded to bear it.
By this first sweat, especially if it happened on the second day, the
patient was never freed from the fever, though greatly relieved. It
was therefore necessary to continue the same medicines, in order, by
a more plentiful sweat, to procure a perfect crisis. Where the sweat
was supposed to be sufficiently copious, and had greatly mitigated the
symptoms, a mild cathartic was given in the morning, though some degree
of fever still remained; the other medicines not being intermitted
during its operation. An anodyne was given in the evening.

In case of an exacerbation of the symptoms or the depression of the
buboes, as sometimes happened on the second or third day, it was useful
to apply a blister just below the tumour. A blister to the head was
useful in cases of coma and debility of the tongue. The natives were
exceedingly averse to the use of blisters; but, having observed that
some who had been judged past recovery had nevertheless struggled
through, apparently from the use of blisters, they at last came into
some degree of credit. Cataplasms, composed of garlic, bread and
vinegar, were advantageously applied to the soles of the feet. These,
as well as blisters, were useful in cases of coma; also emollient
laxative clysters. The dose of the alexipharmics was increased, and
acidulated drinks, in small quantities at a time, given frequently.

To the buboes it was customary to apply suppurative cataplasms; but, as
these could not, where the patient was desirous of walking, be easily
kept on, a diachylon gum plaster was substituted, with the addition
of few cantharides, or a little euphorbium, if a greater stimulus
was judged necessary. In most cases the buboes were left to open of
themselves; the natives being afraid of the lancet or caustic, and
sometimes operators being wanting. No bad consequence ensued on their
being left to open of themselves, nor was any particular treatment
necessary. Where they mortified, the treatment was the same as in
carbuncles, and though, after the separation of the gangrened parts,
the ulcer often remained wide and deep, yet they healed kindly and in a
short time.

Sometimes the carbuncles were scarified, but oftener not. The best
dressings were pledgits of yellow basilicon, with a small proportion of
oil of turpentine, or sometimes tincture of myrrh, with an emollient
cataplasm over all.

Dr. Patrick Russel complains that, in Turky, physicians are laid under
such restraints, by popular prejudices, that they are sometimes obliged
to remain almost passive spectators of the disease. The natives are
fond of bleeding, and will at any time let blood in the hot stages,
when the febrile symptoms run high. About two thirds of the infected
were bled at the arm; but from the rapid progress of the disease, and
the quick transition to the low, languid state, few were bled more
than once, and that usually within the first forty hours. The time of
bleeding was usually the first night, or some time on the second day;
but sometimes not till the third. Where the operation was repeated,
it was usually on the third, sometimes on the fifth, and even on the
sixth; he has even met with instances wherein the patient was three
or four times bled, the last being as late as the seventh day. In his
own practice he usually advised one bleeding at the beginning, except
in the very young, aged, or infirm. On the first day, if not forbid by
circumstances, bleeding was ordered by way of precaution; but on the
succeeding days it was regulated by the state of the pulse, and other
symptoms. Where the infection was slight, and the febrile symptoms
moderate, or did not come on till some days after the eruptions, it
was wholly omitted. The quantity of blood taken away seldom exceeded
eight or ten ounces. Cupping was used by the natives, but never ordered
by Dr. Russel. Children were scarified in the legs. He seldom had an
opportunity of examining the blood drawn from a vein; but, in such
cases as occurred, the general appearance was little different from
that of healthy blood; the crassamentum was sometimes of a darkish
colour, but never sizy or resolved.

With regard to the propriety or impropriety of bleeding, or at least
the success attending it, we can best judge from the histories of
cases given by Dr. Russel at the end of his work. Of these there are
an hundred and twenty, with some supernumeraries, giving an account of
the cases of the attendants, &c. Of these, sixty-five were bled; forty
died, and twenty-five recovered.

Of these hundred and twenty cases at large, fifty-seven recovered, as
many died, and the event of six was unknown. This would tend to give
us some considerable idea of the Doctor’s success; but, when we take
into account the time of the year in which these cases were treated,
the matter will appear in a quite different light. Twenty-seven took
place mostly in the earlier part of the season, and were of consequence
more violent than the others; and, of these, twenty-one died, five
recovered, and the event of the other case was uncertain. Of the rest
only thirty-six died, and fifty-four recovered. Such an excessive
disproportion cannot be ascribed to the medical treatment, but to the
nature of the disease itself, growing milder as it extended wider. In
many of these cases it is not mentioned whether the patients took any
medicines or not; nevertheless, as it must always be supposed that a
physician would prescribe something for his patient, it must also be
supposed that all took medicines, excepting where we are expressly
told that they did not. The cases in which he mentions the medicines
employed were the following:

1. A young man of 20, suddenly seized, was bled largely; had a vomit of
ipecacuanha, which brought off a quantity of bile, but without putting
a stop to the natural retchings. Some diaphoretic medicines were given,
which did not remain on his stomach, and he did not sweat. These were
stopped by a draught of juice of lemons and alkaline salt taken in the
act of effervescence. Sinapisms were applied to the feet, and he died
the third night at midnight.

2. A widow lady about 40, of a thin, delicate habit, in whom the
disease came on gradually, was bled on the third day, and took
diaphoretic medicines and acidulated cordials till the 9th. She died on
the 11th.

3. A Jewish rabbi, between 30 and 40, of a thin, spare habit, was bled
on the 2d day, and died early on the morning of the 4th.

4. A Jewish boy, between seven and eight years old, of a pale,
unhealthy complexion, was repeatedly purged, and had suppurative
cataplasms applied to the buboes without effect. He recovered slowly.
Dr. Russel was not called till the seventh day of the disease, and we
are not informed when the purgatives were administered.

5. A Jewish lad of 14, healthy and florid, was visited on the third
day. He had already been scarified in the legs, and bleeding was
ordered; but, as he became faint, only a small tea-cupful could be
taken away. The blood, after two hours, was found to have a soft and
loose texture, somewhat blackish on the surface; but the quantity of
serum was not greater than usual. It had appeared of a blackish colour
at first. He had a vomit, draughts with spiritus mindereri; afterwards
a diaphoretic mixture and acidulated cordial, and sinapisms to the
feet. On the seventh day he sweated copiously, and was much relieved,
but soon relapsed. On the 10th he sweated early in the morning, and had
a temporary relief, but soon became worse than ever. On the eleventh he
had three stools of black blood. One of these, kept for the Doctor’s
inspection, consisted of about three tea-cupfuls, without any fœtor;
the others were “inconsiderably small.” Some tincture of bark was now
added to his usual mixture. On the 15th he had a purging potion which
operated five times, had an opiate at night, and tincture of bark with
elixir of vitriol was ordered twice a day. Next day he was quite free
of fever, and quickly recovered.

6. A Jew of a thin, spare habit, who took no medicines, died on the
sixth day. His wife, of a delicate frame, and six months gone with
child, was bled in the arm, had “proper drinks” directed for her,
brought forth a child in the agonies of death, and expired on the
sixth day. They were extremely poor, and Dr. Russel says of the house
they inhabited, that it “was one of those miserable dwellings which he
had always considered as one of the receptacles of contagion.” It did
not, however, appear to be so; for, though there were other six in the
family, only one of them was infected, who died in ten days.

7. A youth of a delicate constitution, a French native of Aleppo, was
visited on the morning of the third day. He had a carbuncle on his
neck, which had been mistaken for an ordinary inflammation, and a
physician who had previously visited him applied a galbanum plaster,
ordering also some nitrous medicines; but the plaster giving much pain,
it was changed for a common poultice. Live pigeons were applied to the
feet. On the fourth he had a diaphoretic medicine, and his drinks were
acidulated with spirit of vitriol. The symptoms increasing, sinapisms
were applied to the feet, but without effect. Cataplasms of garlic were
applied next night; he had two copious black stools, not very fœtid,
and two bilious ones in the morning of the sixth. By these stools he
was greatly weakened, and was ordered a cordial with diascordium. He
had another stool, and became much worse. Cataplasms were applied
without effect, and he died on the seventh day. This patient had
a great number of eruptions; but, though six people attended him
constantly, none of them were infected.

8. A Jewish girl of nine years old, of a delicate frame, and sprightly
disposition, was visited on the 4th day. The usual regimen and
medicines were ordered, but she could not be prevailed on to take any
thing besides an acidulated cordial. Palm-oil was externally applied
to a carbuncle near the corner of the mouth, about an inch long, and
the third of an inch broad. This seemed to ease the pain, but did not
prevent it from spreading. The face was also strangely disfigured by
three or four streaks of a pale red colour, shooting up on each side
from the cheeks towards the temples. The gangrene spread rapidly, and
she died on the evening of the tenth day.

9. A stout, healthy Armenian youth, about 20, was visited on the first
day, and took a vomit of ipecacuanha, which brought up a good deal of
bile. An anodyne was given at night, but without effect. He took no
medicines afterwards but an acidulated cordial. On the third he eat a
quantity of cherries, and drank some iced water. He died on the fourth.
Here the infection spread violently, only one out of six in the same
house escaping the disease. Three died.

10. An Armenian woman in the seventh month of her pregnancy. She was
bled the first day, had afterwards diaphoretic boluses, but did not
sweat. On the third day she was delivered of a dead child, and seemed
much better, but died at night. After death the body was entirely
covered with purple marks.

11. A boy was bled and had an alexipharmic mixture the first day. A
diarrhœa came on, and diascordium was added to the mixture without
success. He died the third night. The infection was violent, only one
in the house escaping.

12. A Jew of middle age and gross habit of body was bled on the
second day. He was visited on the fifth, had diaphoretic powders, and
sinapisms were ordered without success. He died on the 6th.

13. A Christian youth of 17, taken suddenly, was visited on the second
day. A cataplasm was applied to the groin; he had a vomit of ipecacuan,
and a diaphoretic draught with nitre and diascordium at night, but did
not sweat. Next day he had acidulated drinks, a mixture with sweet
spirit of nitre, and a small proportion of nitre itself. On the fourth,
he had two stools, of a reddish colour like blood, after which he
became much worse. In the night he had two other stools, which seemed
to lower him. Throughout the day a larger portion of nitre had been
added to his mixture, and three tea-cupfuls of blood were taken away,
without the Doctor’s knowledge, by cupping. On the fifth the nitre
was omitted; he was ordered an astringent cordial, but it was not
given; however, the diaphoretic medicines were continued, and he had
three loose stools, which sunk him greatly. Next day he seemed past
recovery; lying motionless, insensible, his breathing quick, laborious
and interrupted; the skin not cold, but the feverish heat gone, and
his countenance ghastly. From this lethargic state the women attempted
frequently to rouse him, by applying vinegar to his nostrils, calling
him loudly by his name, and such like means, by which they sometimes
succeeded; but, though he opened his eyes, and gave signs of sense, he
could not be prevailed on to drink; and he remained silent. He would
then, for some time, writhe his body as in mortal agony, and again
relapse into lethargy. This dreadful paroxysm, however, began to wear
off about noon; and at night he was less disturbed than usual. On the
seventh day he was manifestly better; he had a looseness, with gripes,
for which the white decoction was ordered; and he had tincture of
bark thrice in twenty-four hours. On the sixteenth day the fever was
entirely gone. The Doctor observes that this patient sweated much less
than was usual with those who recovered.

14. A Christian boy about 17 was visited on the 4th day, having taken
some absorbent powders on the 2d from another physician. The family
would allow no other medicines to be given, except a few grains of
bezoar, and he died next day.

15. An Italian, a man about 40, of a gross habit of body, and addicted
to drinking, but who, finding himself somewhat indisposed, had for two
or three days lived temperately, was visited on the second day of his
illness, had a diaphoretic mixture, and a laxative medicine, without
relief. In the night between the 5th and 6th he had some retchings to
vomit. Next day he complained of a pain at the pit of the stomach, had
a vomit of ipecacuanha, which brought off a considerable quantity of
bile by vomit and stool, but without any apparent relief. He had two
fœtid stools, and was ordered a cordial with volatiles. On the 7th
his pulse was exceedingly sunk, and his extremities had been as cold
as ice, but with very little alteration in the eyes or countenance.
The patient did not know that these parts had lost their heat; and,
notwithstanding this change, the sensation still remained in them. He
died on the afternoon of the 8th day. This patient had no eruptions.

16. A Christian merchant about 50, of an atrabilious habit, and subject
to the hæmorrhoids, on being taken ill drank immoderately of cold
water. He was visited next day. In the afternoon about ten ounces of
blood were taken away, and, as his pulse rose after the operation,
he lost, by Dr. Russel’s order, six ounces more. Three ounces
were afterwards taken away by cupping, and about as much more was
accidentally lost by the loosening of the bandage of the arm; so that
about 24 ounces were taken away in all. Next day he got a few drops of
Carmelite water, a kind of spiritous cordial, which he vomited, had a
blister and sinapisms applied, and died between 10 and 11 at night. He
had no eruptions.

17. An Armenian youth was visited on the morning of the third day, was
bled, and had a saline draught every four or five hours. On the fifth
he was removed into a more airy chamber, and had Huxham’s tincture of
the bark. He died on the ninth day.

18. A young lady of French extraction, of a thin, slender make,
was visited on the morning of the second day. On the third she had
diaphoretic powders, and lost a few ounces of blood by cupping, without
the Doctor’s knowledge; she had a diaphoretic mixture, and died on the
sixth day.

From these accounts it is easy to see, that, in violent cases of the
plague, medicine can do little or nothing. Such cases generally occur
in the earlier months of the season, though they may take place, and
do take place in great numbers, at any time. In the beginning of the
season the patients are almost all attacked in this violent manner, and
very seldom recover, whether they take medicines or not. It being then
an established fact, that as the epidemic season advances the disease
grows milder, and many more continue to recover of themselves than
did so at first, we are naturally led to suppose that a multitude of
those who recovered after taking the medicines would have done the same
without them. Little therefore needs be said of the immense number of
prescriptions found in authors who have written upon the plague, as it
may generally be supposed that at certain times these would have been
ineffectual, and at others they were useless.--The following is an
epitome of Dr. Patrick Russel’s practice:

1. Bleeding as early as possible, seldom repeated, except where
manifestly indicated by circumstances.

2. Vomiting, if spontaneous, was encouraged by warm water. If the
patient was affected by nausea, vomiting was provoked by warm water or
camomile tea, assisted by a feather. If a bitter taste in the mouth was
complained of, ten or fifteen grains of ipecacuanha were given. The
times of remission were laid hold of for those remedies.

3. Where spontaneous vomiting continued too long, a saline mixture was
given, sometimes with opiates and external applications.

4. The stomach being settled, mild sudorifics were given in small
doses, every five or six hours. In the beginning, nitre was joined
with contrayerva, but where it occasioned loose stools, was left off.
Spiritus mindereri and saline mixture were also given as sudorifics.

5. In case of diarrhœa, dilution was first prescribed and then the
white decoction. Laxative medicines were seldom admitted by the friends
of the patient. Diascordium and opiates were used in cases of obstinate
diarrhœa.

6. In the advance of the distemper it was found more eligible to give
the sudorifics at shorter intervals, when occasion required, than to
augment the dose, which was apt to occasion disgust, and a rejection
of medicine entirely; consequences which also attended an attempt to
heighten the power of the medicines themselves. The general design was
to make their operation coincide with the periodical determination to
the skin naturally occurring in the disease.

7. The sudorifics exhibited having but small power by themselves, it
was found necessary to assist them by dilution, as well as in every
other method which could be attempted. If the patient was not naturally
inclined to drink, he was encouraged to it by offering agreeable
liquids, either hot or cold at the person’s option.

8. The diet was the same as in other acute distempers. No animal
food stronger than chicken broth was allowed; the rest confided of
farinacea and leguminous vegetables. “It was certainly necessary (says
our author) to a certain degree, to support nature by proper food; but
to force it upon a nauseating stomach seems to have been irrationally
recommended; and, where attempted, which the over care of the nurses
frequently did, usually excited vomiting. I sometimes wished to
give wine, but a religious bar lay in the way of Mahommedans, and a
prejudice against it, in all fevers, rendered it equally inadmissible
among the Christians and Jews.”

9. For oppression at the præcordia, mild cordials, acidulated drinks
and cool air were found useful. Throughout the disease access of cool
air to the chamber was constantly allowed, and, where the chamber
itself was not sufficiently airy, the bed was removed to the house top.
Towards the height of the exacerbations, however, when there happened
to be the least appearance of moisture on the skin, the sick were kept
moderately covered up from the chin downward.

10. After the height, and through the decline of the disease, the bark
in substance, or Huxham’s tincture, were given instead of the ordinary
sudorifics.

In the plague which took place in the Russian army, the greatest
confidence seems to have been put in vomits. The disease commonly began
with a dull pain in the head, resembling that produced by the fumes
of charcoal, accompanied with shivering, universal weakness, &c.[135]
On the first appearance of these a vomit was given, working it off
with acid drinks. “If the nausea and bitter taste in the mouth was not
removed by the first, they gave a second, and sometimes a third or
fourth; nay, they sometimes, if the symptoms were very urgent, gave
two or three in the space of twelve hours, as there is no time to be
lost in this disease; for they did not find this species of evacuation
subject to the same inconvenience with purges, which a man in the
plague is unable to support; nay, they are even dangerous, though he
bears brisk vomits, and a repetition of them, when the nature of the
case requires it.

  [135] Duncan’s Med. Comment. vol. viii, p. 352.

“The stomach being thus cleansed, they gave every morning a powder
composed of twenty grains of rhubarb, mixed with as much flower of
brimstone, and three grains of ipecacuanha, exhibiting also, every
hour, five grains of pure nitre mixed with two grains of camphor; and,
if costive, a laxative clyster was given every evening, composed of
decoction of camomile, wine vinegar, with or without soap, according to
circumstances.

“The head, temples and buboes were frequently washed with warm vinegar,
and the last urged to suppuration with emollient cataplasms; but, in
case they were found to baffle all attempts to bring them forward,
they were then scarified or extirpated, and the patient ordered to
drink plentifully of _lime-water_. Bark was given after evacuation,
joined to the flower of brimstone in the proportion of one ounce of
the former to a drachm of the latter, divided into sixteen powders,
and taken in twenty-four hours. When delirium came on, blisters were
applied to the legs and arms, and camphor given largely. Vegetable and
mineral acids were given indiscriminately; but they found the vegetable
kind sometimes remain on the stomach when the other was thrown up; and
of the latter they preferred the vitriolic. Acidulated drinks were
given in quantity through the whole disease, and the food consisted of
acidulated water-gruel, and fruit when they could procure any. The air
of the room was kept charged with acetous vapours, as much as possible,
and it was remarked, that, while the bitter taste remained, there was
little hope of the disease abating.”

According to Baron Ash, “the plague does not depend upon any
constitution of the air, but is communicated only by contact, and they
had repeatedly succeeded in suppressing it in different divisions
of the army, by the immediate separation of the infected with their
attendants, and burning every thing belonging to them, or that they
had touched. They found the greatest advantage in keeping the soldiers
ignorant of its existence till suppressed; for by this means they
preserved their peace of mind, and health of body; and they found an
exact military discipline the best preservative against the disease.
For the cure of those infected they found the cold regimen, a free
circulation of air, vegetable and mineral acids, ipecacuanha, rhubarb
and bark, to be the properest remedies. That, to purify the air in
hospitals appropriated for their reception, gun-powder was found most
efficacious, probably from the commotion given to the air in explosion,
over and above its action in common with other fumes. To resist
infection, courage and fortitude of mind is necessary, as consternation
and terror seem to prepare the body for the reception of the disease.”

Dr. Sydenham seemed to have as great an opinion of bleeding, as
the Russian physicians of vomits. Considering the plague as merely
inflammatory, he lays the whole strength of the cure upon bleeding,
which he greatly prefers to any other remedy. The quantities he took
away were very considerable; and he gives an instance of a patient
who died from not having enough taken away. He also informs us, that,
during the civil wars in England, the plague raged in several places.
Being accidentally brought to Dunstar castle in Somersetshire, a
surgeon, who had travelled much in foreign parts, applied for leave
to give the garrison what assistance he could. This being granted, he
bled them, every man as he stood, without distinction, till ready to
drop down; the blood was suffered to flow down upon the ground, so
that no account could be taken of the quantity. They were then ordered
to lie in their tents; and, though no kind of remedy was given after
bleeding, every one recovered.[136] Notwithstanding his opinion of
bleeding, however, this celebrated physician was obliged to attempt the
cure by sweating, which he says he preferred to bleeding on account of
its not weakening the patient so much, nor hazarding the reputation of
the physician; yet he says it is prejudicial in young people where the
powers of life are strong. His improved method therefore was, first
to bleed moderately, if no swelling had appeared, by which means a
sweat would be more safely and easily raised. The bleeding is to be
performed in bed, after which the patient must be covered up with the
bed-clothes, and a piece of flanel applied to the forehead. This last
expedient, he says, contributes more to the raising of a sweat than
one would imagine. If no vomiting ensued, he administered sudorific
medicines internally. But, if the stomach cannot retain any thing, he
proposes to begin the sweating merely by the weight of the clothes,
and now and then throwing part of the sheet over the face. The sweat
being thus begun, the vomiting, however violent, generally stops, and
the medicines will be retained, so that as plentiful a perspiration as
we can desire may be excited. An instance of his success in this way
he gives in an apothecary who applied to him in behalf of his brother.
A sweat being proposed, the apothecary told him that he had given
him several strong sudorifics, all of which had been thrown up; but
the Doctor, having first sweated him moderately by the bed-clothes,
afterwards gave him a large dose of Venice treacle; which operating
powerfully, he recovered from the disease. He advises the sweat to be
kept up without intermission for twenty-four hours; a smaller time
being insufficient to remove the disease, and a stoppage of the
perspiration certainly attended with a return of the bad symptoms. On
this occasion he censures Diemerbroeck and others for advising to stop
the sweat on every slight occasion. The linen is to be allowed to dry
on the patient’s body, he must take all his liquids warm, and continue
the use of a diluting fluid. Sage posset drink is what he recommends.
Next morning the cure was finished by a purge of senna, tamarinds,
&c. Where a swelling appears, he directs to forbear bleeding even in
such as are not apt to sweat, least the patient should die suddenly
from a return of the morbific matter into the vessels. Bleeding,
however, might be used with safety even in this case, provided a sweat
was instantly to be raised; and thus he thinks the swelling might be
dispersed perhaps with more safety than by waiting for its suppuration.

  [136] Dr. Dover, who wrote, in 1732, the _Ancient
  Physician’s Legacy_, had lodged his soldiers in a church in which
  those who died of a plague had been buried. An hundred and eighty of
  the soldiers were seized either with petechiæ or buboes. He ordered
  them all to be bled in such quick succession, that the arm of the
  first was not bound up till the blood flowed from the last. Thus
  every one lost about an hundred ounces (upwards of three quarts.) He
  then ordered them water acidulated with spirit of vitriol for their
  drink; and by this treatment all recovered excepting eight, who would
  not refrain from spiritous liquors. This was transacted in Peru:
  but in Europe the plague will scarce bear bleeding to a few ounces.
  (Sauvages.)

This may be accounted an epitome of the most approved modern practice
in pestilential cases. The Russian physicians above quoted seem to
speak with most confidence of their success. They, however, “lay
great stress upon distinguishing the plague from the worst kind of
malignant fever in hot countries; and it is not without reason, as bad
consequences have attended the confounding of them on the breaking
out of the plague. I am credibly informed that the great havock made
in Moscow was principally owing to this circumstance; for it obtained
some time before it was discovered by gentlemen unacquainted with the
disease, and before they would acknowledge its existence, although
some veteran army practitioners recognised its appearance under one of
its forms, and endeavoured to alarm their brethren, but in vain, for a
time.”[137]

  [137] Duncan’s Med. Comment. vol. viii, p. 359.

From this it is natural to conclude, that, when the disease was once
fairly discovered and attacked by the powers of medicine, it could
not make much resistance; yet Dr. Mertens, speaking of this very
plague, says, that owing to the rapidity of the distemper, and many
inducements to conceal it, _little can be said of remedies_ in the
plague. He divides the distemper into two kinds, the nervous and
putrid; the former “comprehending merely that degree of confusion and
disturbance given to the nervous system on the first introduction of
the miasma, and the latter commencing at the time the miasma begins to
operate upon the blood and other fluids by assimilating them to their
own putrid nature.” In the nervous state the miasma has sometimes been
carried off by sweat, gentle diaphoretics, camphorated emulsions,
juleps of camphor and musk. Gentle emetics, particularly ipecacuanha,
were found useful; but James’s powder (which was imported from England
in great quantity) did not answer any good purpose. In the putrid
state, the bark and mineral acids were useful; purgatives were hurtful,
blood-letting inadvisable, and scarifying the carbuncles, recommended
by almost every writer, attended with no good effect.

Few of the modern travellers who have visited the countries in which
the plague is frequent, being versed in medicine, have said much about
the cure of it. Mariti only says, that, in the island of Cyprus,
infected patients were allowed no other diet than pure water, panada,
rice, tea, &c. Some thought to ward off the disease by drinking strong
liquors, but these _almost always_ fell victims to it. Whatever their
methods were, indeed, they must certainly have been very ineffectual,
since the same author informs us that, in the plague of 1759, in many
parts of that island there were not a sufficiency of inhabitants left
to cultivate the ground.

Diemerbroeck, whose name justly ranks high among those who have
written on the plague, trusts mostly to sudorific medicines. Bleeding,
according to him, is absolutely to be avoided, as well as purging
and vomiting. He directed first that the chambers of the sick should
be kept clean, and the air purified three or four times a day by
fumigations, and that the sick should take (in the beginning, the
first, second, or third day) a _sweating draught_, and being well
covered with blankets plentiful sweats were promoted for two or three
hours or more (always having a regard to the patient’s strength.) If
the patient did not sweat easily, bags filled with hot, dry sand were
applied to the feet, armpits and groin. If the sick were not eased by
the first sweat, it was repeated in a few hours; but if, after the
second sweat, the fever and other symptoms still increased, it was the
worst sign. After ten or twelve hours, and on the following days, they
were repeated four or five times as occasion required. Besides this he
directed apozems, antidotes, &c. which, as it is most probable they had
no effect in removing the disease, it is needless to trouble the reader
with.[138]

  [138] As it might by some be deemed an affront offered to the wisdom
  of antiquity, should we pass over in silence the opinions of the more
  ancient physicians, I shall in this note give a short account of some
  of their most remarkable modes of practice, as they are recorded in
  Burnet’s _Thesaurus_.

  1. Forestus, in many respects a respectable author, recommends an
  _antidote_ composed of equal parts of rue, figs and almonds, beat
  into a pulp in a stone mortar with a wooden pestle till united
  (which is not very easily done) into an uniform mass, adding as
  much syrup of citrons with vinegar as would render it soft, with a
  little powdered salt put in last. The efficacy of this he tells us
  he experienced in himself as well as all his family as a preventive;
  himself taking in the morning the bigness of a small nutmeg of this,
  made up into a confection with the ancient theriac, mithridate,
  Armenian bole, terrasigillata, &c.

  In his regular practice (for the above must be accounted quackery)
  he advises bleeding within the first twelve, or at most twenty-four,
  hours; such as were bled afterwards he says died. If performed in
  seven or eight hours after the commencement of the disease the
  cure went on the better. Where bleeding was inadvisable he used
  cupping with scarifications, finishing the cure with sweating and
  cordials. He remarks that where black tumours or eschars, lentil
  shaped, appeared, the disease always proved mortal, without a single
  exception. These were small, like a grain of black pepper, and
  therefore called by the vulgar _peppercorn_; undoubtedly the _tokens_
  of Dr. Hodges.

  2. Hildanus, also a respectable writer, has an high opinion of issues
  as a preventive. He says he never knew but one or two (and those of
  a very bad habit of body) who had issues in their legs and arms that
  perished in the plague, and says that he has known its efficacy as
  a preventive not only in himself but many others. He says he kept
  two issues in his own body, one in the left arm, the other in the
  right leg. (See above p. 339) To the same purpose Mercurialis relates
  that he never knew but one, and he was a _priest_, who died of the
  plague having an issue. He says also that he had inquired of many
  other physicians, who all gave a similar testimony. According to
  him, in the plague at Lausanne, all who were attacked by vomiting or
  looseness, and almost all who were bled, fell victims to the disease.

  As preventives he advises amulets made up of arsenic, powder of
  _toads_, and _other things_. These are to be hanged round the neck in
  times of plague, and are _undoubtedly_ of great virtue (_maximam_ ad
  _præservationem vim habere, non est quod dubites!_) This remedy he
  says he had from his preceptor _Cosmas Slotanus_, a very celebrated
  surgeon.

  Brine of pork is another preventive, which he never tried himself,
  but asks Sennerius about it. It was recommended to Hildanus by a
  lawyer of his acquaintance. The brine is first to be boiled in a
  kettle, and well skimmed, till it becomes clear, poured into earthen
  vessels. and kept shut up from the air for a twelvemonth; after which
  it was fit for use. A draught of this was given to people infected
  with plague, and operated by sweat, stool or vomit, or perhaps both
  by vomit and stool. The patient was to abstain from drink for some
  hours after. The brine of _anchovies_ is recommended by Sam. Formius,
  as useful in the plague at Montpelier in 1630.

  3. The same author (Formius) tells us of a man and his wife and
  wife’s sister, in Montpelier, who, being taken with the plague,
  swallowed a solution of their own excrements in urine, _strained
  through a linen cloth_, and thus got clear of the distemper. It
  produced excessive vomiting and purging. Dr. Russel mentions one of
  his patients, who, he suspected, had got a dose of bezoar in urine.

  4. Johannes Helmontius says, that _to his certain knowledge_ (me
  conscio) _Hibernus Butlerus_ cured some thousands of the plague, at
  London; though unhappily our author got only part of the secret,
  and which is to the following purpose. “He ordered me to suspend
  by the legs before the fire, a large _toad_ taken in the afternoon
  in the month of June; putting below him a cake of yellow wax. At
  length, after three days suspension, the toad vomited earth, and some
  _walking insects_ (insectas ambulantes) viz. _flies_ with shining
  wings of a greenish colour, as if gilt: the toad died immediately
  after this evacuation, nor did it take place, notwithstanding his
  suspension till the third day. He (Butlerus) then told me that I had
  medicine enough for curing _forty thousand_ people infected with
  the plague, and promised to show me the mystery of the matter (rei
  cardinem) but being suddenly sent into banishment he departed.” The
  best part of the secret being thus lost, it is needless to trouble
  the reader with any further account of experiments made with other
  toads roasted alive, powdered and made up into troches,&c. presuming
  that these could not equal the value of the original receipt. I
  proceed therefore,

  5. To the antidote of the celebrated Avenzoar, who drove away the
  plague by the smell of the _urine_ of an _he goat_; and Mercurialis
  says that in the house of a most reverend canon in Hungary, he saw a
  large he goat kept for this purpose.

  6. From such horribly disgusting remedies we certainly turn with
  pleasure to the elegant tablets prepared for the Emperor Maximilian
  II. These were composed of Armenian bole, prepared pearl, prepared
  coral, prepared emeralds, prepared jacinct, gold-leaves (ingredients
  in a medical view equally efficacious with chalk or oyster shells)
  along with a little ambergrease and some other ingredients of
  little value, as medicines, and made into tablets with conserve
  of roses----It is needless to spend time in commenting on such
  ridiculous remedies; suffice it to say, that the intention of all
  rational practice both ancient and modern has been to effect a cure
  by sweating. From the instance related by Sydenham, as well as that
  of Dr. Power above mentioned, it seems, that if the exact time in
  which the disease begins could be known, it might be carried off
  by profuse blood-letting; but as this for the most part cannot be
  discovered, it is certainly better to wait, even though the event
  should not prove favourable, than to run the risk of killing, the
  patient instantly by an ignorant effort to save him.

That a free perspiration is the natural cure of the plague, seems
to be allowed by almost all writers of credit. Dr. Russel says,
“Of all excretions, _that_ by the skin would seem to be the most
materially important in the plague. Where the skin remains perpetually
dry, or where short and precipitate sweats are attended with no
favourable alteration, danger is always to be apprehended. On the
other hand, sweats, at certain periods of the disease, appeared
clearly critical in a greater or less degree. They were followed by a
manifest alteration for the better, and by their repetition the fever
was carried entirely off, or reduced to symptomatic exacerbations,
seemingly dependent on the eruptions.” He adds, that he never observed
blood exude through the pores, nor did he observe the sweat to be
remarkably offensive; or in any degree so remarkable as in some
eruptive fevers, particularly in the small-pox before eruption.
Dr. Hodges, however, says that in the plague of London sweats were
sometimes extremely acrid and fœtid; and that they were met with of
various colours, such as purple, green, black, or blood-coloured.
Sometimes it was cold, though the patient was tormented with
intolerable inward heat and drought; and would continue even after
death; but he was of opinion that sweat is the natural crisis of the
distemper.

Besides those symptoms of the plague which have been enumerated, there
are others, particularly hæmorrhages and convulsions, with which it is
sometimes attended. These it has in common with the yellow fever, and
therefore are considered in the second part of the work. I now conclude
this part with a short retrospect of the principal facts which to me
seem to be the result of the investigation. 1. That the plague is of an
unknown (I believe it of _divine_) original. 2. That in the countries
on which it first was sent, it still remains, and from them has always
been propagated to others, without a single well attested instance to
the contrary. 3. That the means by which the distemper usually has been
propagated are _war_ and _commerce_. 4. That the disease differs from
all others in having a more violent tendency to inflammation, insomuch
that it approaches to actual accension; nay, that the extraordinary
instances of spontaneous burning we read of are to be accounted only
the highest degree of this disease. 5. That the immediate or proximate
cause of the plague is a tendency in the blood and other fluids to
discharge upon certain parts the latent heat they contain, in such
quantity as to destroy these parts entirely, and to convert them
into a kind of coaly substance. 6. That this tendency depends on a
certain inexplicable action of the external atmosphere, particularly
of the elementary fire contained in it, and of which it principally
consists.[139] 7. The approach of a plague cannot be foretold, either
from the constitution of the atmosphere, earthquakes, storms, or any
other natural phenomena. 8. The plague is an eruptive disease, and it
is known to be so by the _certain death_ of all in whom eruptions do
not appear; a tendency to eruption being _always_ observed where life
remained long enough. 9. The contagion of the plague diffuses itself
from a small space all around, lessening in violence the farther it
is diffused. In its most concentrated state it hath proved invincible
by medicine; in its mild state it requires none;[140] so that in the
plague the medical powers are found of less avail than in any other
acute distemper. 10. The natural cure of the plague is by perspiration
or sweat, and this perhaps is the only evacuation which ought to be
kept in view, as having a salutary tendency, by those who attend the
sick.[141]

  [139] These two last conclusions (though I believe them myself) are
  proposed only as probable conjectures, which as yet I see nothing to
  contradict.

  [140] See p. 282.

  [141] The operation of oil so much recommended by Mr. Baldwin is said
  to be by producing sweat. (See above p. 341.)


END OF THE FIRST PART.



A TREATISE ON THE Plague and Yellow Fever.



PART SECOND.

_Of the Yellow Fever._


  We now come to treat of a disease, less fatal indeed than the Asiatic
  plague, but yet so deadly in its nature in the Western World, that
  it has of late been confounded with the former, and attempts made
  to prove that they are both to be considered only as degrees of
  the same disease, and that both have been recorded by historians
  indiscriminately under the common appellation of _plague_ or
  pestilence. To investigate this matter candidly, and to show that
  there is a real and essential difference between the two, as far as
  we can credit testimonies drawn from the most respectable writers,
  shall be the work of the following part of this treatise.



SECTION I.

_History of the Yellow Fever._


The distemper now under consideration has been commonly distinguished
by two different names; one of which is the _Yellow Fever_, the other
the _Black Vomit_. Both of these are taken from symptoms so remarkable
(though not occurring in every case) that, had the disease existed
in ancient times, we can scarce think but some of the historians of
antiquity would have taken notice that in such a plague those who died
generally became yellow, or that they had a continual vomiting of black
matter, which could not be stopped. Black or bilious vomitings are
indeed mentioned, though not as the principal symptom, but the yellow
colour is not once taken notice of. Dr. Hodges indeed mentions a single
instance of a patient who became all over of a _green_ colour; but as
a change of colour is not taken notice of in the plague as a general
symptom, either by him or by any other writer, we must conclude that
this distemper (the yellow fever) has been observed only in modern
times.

When Columbus first visited the West India islands, we hear nothing of
his having found such a disease existing there; nor does it appear that
it was known among the many Spanish adventurers who succeeded him, and
who subdued such immense tracts on the Southern Continent. Soon after
the settlement of some of the West India islands, however, by other
European nations, this disease began to make its appearance, though
at what time is still uncertain. Dr. Hillary says, that, “as we have
no accounts of this disease in the ancients, nor even in the Arabian
writers, who lived and practised in the hot climate, we must give it
_some name_;” and he calls it the _putrid bilious fever_. “From the
best and most authentic account (adds he) that I can obtain, as also
from the nature and symptoms of the disease, it appears to be a disease
that is indigenous[142] to the West India islands and the continent of
America which is situated between the tropics, and most probably to all
other countries within the torrid zone. But I cannot conceive what were
the motives which induced Dr. Warren to think that this fever was first
brought from Palestine to Marseilles, and from thence to Martinique,
and so to Barbadoes, about thirty-seven years since (1721 or 1722.) A
better inquiry would have informed him, that this fever had frequently
appeared, in this and the other West India islands, many years before:
for several judicious practitioners, who were then, and are now, living
here, whose business was, visiting the sick the greatest part of their
life time, some of them almost eighty years of age, remember to have
seen this fever frequently in this island, not only many years before
that time, but many years before that learned gentleman came to it.”

  [142] Naturally belonging to the climate.

To the same purpose Dr. Mosely says, “Warren, though he lived at
Barbadoes in 1739, supposes it never appeared in that island till about
the year 1721, and that it was then brought from Martinique in the Lynn
man of war. He says the second appearance of it there was in 1733,
and that it then came also from Martinique. He undertakes to show,
that it is a disease of Asiatic extract; and says, that a _Provencale_
fleet arrived at Port St. Pierre in Martinique, from Marseilles, on
board which were several bales of Levant goods which were taken in at
Marseilles from a ship just arrived from St. Jean D’Acre (probably
the Ptolemais of the ancients.) Upon opening these bales of goods at
Port St. Pierre, this distemper immediately shewed itself; many of
the people were instantly seized, some died almost suddenly, others
in a few days, and some lingered longer; and the contagion, still
spreading, made great havock at the beginning. He says he had this
account from Mr. Nelson, an English surgeon, who was seized with the
disease at Martinique, and died of it a few days after his arrival at
Barbadoes. He says, it is very probable that the same fever, or one of
very near resemblance and affinity, may first have been carried among
the American Spaniards (among whom it is now endemic) in somewhat a
like manner; and that possibly some peculiar qualities in the air and
climate might have fostered and maintained it there ever since.”

Dr. Mosely at once concludes the whole of this account to be
_fabulous_, but whether fabricated by Dr. Warren or the surgeon, he
does not say. He then appeals to Dr. Towne, who wrote before Warren,
in 1776, but takes no notice of this _chimerical_ origin of the yellow
fever, but considers it as an endemical disease in the West Indies.
Hillary’s opinion already given is also quoted.

The next evidence is that of Mr. Hughes, who, though not a medical man,
has written on the first appearance of the yellow fever in Barbadoes
in the following terms: Dr. _Gamble_ remembers that it was very
“fatal here in the year 1691, and that it was then called the _new
distemper_, and afterwards _Kendal’s fever_, the _pestilential fever_,
and the _bilious fever_. The same symptoms did not always appear in
all patients, nor alike in every year when it visited us. It is most
commonly rife and fatal in May, June, July and August, and then mostly
among strangers; though a great many of the inhabitants, in the year
1696, died of it; and a great many at different periods since.”

As to the first appearance of the disease in the West India islands
we have no accounts which have been deemed sufficiently authentic,
though indeed it must be confessed that the doubts seem to be derived
as much from an attachment to theory as to the investigation of truth.
“The _endemial causus_, or _yellow fever_, (says Dr. Mosely) which is
the terror of Europeans newly arrived in the West Indies, is called
by the French _la maladie de Siam_. Monsieur Pouppe Desportes, who
practised physic at _St. Dominique_ from 1732 to 1748, and who had more
experience, and has written from better information on the diseases of
that colony, than any of his countrymen, says that this fever was so
called from its being first taken notice of in the island of Martinique
at a time when some vessels were there from Siam. This account, though
probably true enough as to the time of its being first observed in
the French colonies, is extremely incorrect in other respects: for
M. Desportes has not only admitted a supposition that the disease
originated among these East Indian mariners, but calls it pestilential,
and says that the Europeans are almost the only victims to it.

“The generality of the French writers say that it was brought directly
from Siam, in a merchant ship, and communicated to the people of
Martinique, whence the contagion was carried to St. Dominique, but that
sailors were the only people attacked by it, whence it was called _la
fievre matelotte_.”

This account seems to carry no improbability in it; nevertheless
Dr. Mosely rejects it upon grounds that are very far from being
indisputable. “The French writers (says he) have not been at the
trouble to consider that a disease brought from Siam in the East
Indies, in a similar latitude to the West India islands, would be most
likely to affect the natives, living in a climate similar to that in
which the disease originated, rather than the Europeans of so different
a temperament of body.” But this argument would prove too much; for if
the disease would be most likely to affect the natives in a climate
_similar_ to that in which the disease originated, surely it would
be still more likely to attack the natives in _that very climate_ in
which the disease did originate, and that Europeans would be free. But
the very reverse is the case. The disease, according to Dr. Moseley
himself, originates in the West Indies; and yet Europeans, especially
those newly arrived, are particularly objects of its vengeance.

“But (adds our author) the fact is, that this disease never attacks
either white or black natives of hot climates; neither was it brought
from Siam; and though it is possible, from the heat of the climate,
that it may frequently appear there, or in any other tropical
country (though BARRERE says it is unknown at _Cayenne_) no history
of that country that I have yet met with mentions such a disease;
notwithstanding what many writers have boldly advanced to the contrary.”

Here it is evident we have no argument, but a parcel of assertions,
the first of which contradicts what he had just before quoted from Mr.
Hughes. For the latter informs us that in 1696 a great many of the
_inhabitants_ died of it as well as strangers. His not meeting with
it in any history of Siam is not a proof of its non-existence in the
country, neither indeed does he himself think that it is so, as he
tells us that it may possibly appear there, or in any other tropical
country.

In Sauvages’s Nosology we find the plague distinguished into a number
of different species, among which there is one called the _plague
of Siam_. This, he says, was in the year 1685 brought from Siam to
Martinico, in the ship called the _Oriflame_. This seems to have been
the _yellow fever_, and the symptoms are considered in the following
section. This date agrees exactly with what Mr. Hughes says in the
place above quoted, that it was violent in Barbadoes in the year 1691,
when it went by the names of the _new fever_, and _Kendal’s fever_.
Both these names imply that the disease had been but lately known, and
that it was by no means a native of the climate. It must either have
been _imported_ therefore from some other country, or it must have
_originated_ in consequence of the settlement of some Europeans in a
climate so dissimilar to their own, while some of them still continued
to ramble from one country to another, occasionally visiting all,
without taking up their residence in any.

Martinique seems to have been the first place where this distemper
made its appearance; and from thence it seems quickly to have extended
itself to St. Domingo and Barbadoes. Its farther progress, however,
cannot be traced, nor can we tell exactly what time it first entered
the continent. Whether the true plague was ever imported into the
Western Continent cannot at present be ascertained, neither can we
tell what diseases the Indians were subject to before the arrival of
the Europeans. The Spaniards, who first arrived, are allowed to have
been less subject to the plague than other nations,[143] but they were
quickly followed by those who had no such exemption. Sebastian Cabot
discovered the North American Continent for Henry VII of England, very
soon after, if not before Columbus discovered the Southern Continent
for the king of Spain. This was a very suspicious time; for Henry
VII himself had introduced the sweating sickness into England only
thirteen years before;[144] and in those days the plague seems never to
have been eradicated; so that it is by no means impossible that these
first adventurers might have communicated to the Indians with whom they
had any communication, the seeds of diseases totally unknown to them
before. Certain it is, that the North American Indians were subject to
epidemics before the settlement of any English colonies among them.
Hutchinson in his History of Massachusetts takes notice of the Indians
having been greatly weakened by an epidemic, which was attributed to
an unfavourable season, in consequence of which they were obliged to
feed upon unripe squashes, fruits, &c. We know not the nature of the
distemper, though, from the circumstance just mentioned, we may not
unreasonably conjecture it to have been of the pestilential kind.
That epidemics still continue among these people we also know from
the testimony of Capt. Carver, who found one of their towns deserted,
and the inhabitants fled into the woods, on account of an epidemic
disorder; but what the nature of it was he does not inform us.[145]

  [143] See p. 319.

  [144] See p. 17.

  [145] In Belknap’s Biography we have a more particular account of
  this _pestilence_, as it is called, and which, if the relations
  there given are to be credited, certainly determines the disease
  in question to have been the yellow fever. The account is to the
  following purpose: Lord Arundel, of Wardour, had employed a captain
  Weymouth to search for a N. W. passage to India. In this he failed,
  but falling in with a river, supposed to be either the Kennebeck or
  Penobscot, he brought from thence five of the natives, with whom he
  landed at Plymouth in July 1605. Three of the Indians were taken into
  the family of Sir Ferdinando Gorges; and from these many particulars
  were obtained respecting their country, which being eagerly attended
  to by Gorges, he formed a plan of advancing his fortune by a thorough
  discovery of the country. Two vessels were accordingly fitted out;
  one of which failed, but the other brought such information as gave
  encouragement to attempt the founding of a colony. Two of the natives
  who had been brought to England were sent back, and 45 persons were
  left on the continent to begin the settlement; but these, having
  undergone great hardships, quitted the place in 1608. Gorges,
  however was not discouraged. He sent out one of his servants, by
  name _Richard Vines_, and some others, whom he hired to stay in the
  country all winter.

  “Mr. Vines and his companions were received by the Indians with
  great hospitality, though their residence among them was rendered
  hazardous; both by a war which raged among them, and by a pestilence
  which accompanied or succeeded it.

  “This war and pestilence are frequently spoken of by the historians
  of New England, as remarkable events, in the course of Providence,
  which prepared the way for the establishment of an European colony.
  Concerning the war, we know nothing more than this, that it was begun
  by the Tarratenes, a nation who resided eastward of Penobscot. These
  formidable people surprised the bashaba, or chief sachem, at his head
  quarters, and destroyed him with all his family; upon which all the
  other sachems who were subordinate to him quarrelled among themselves
  for the sovereignty; and in these dissensions many of them as well
  as of their unhappy people perished. Of what particular kind the
  pestilence was, we have no certain[146] information, but it seems to
  have been a disorder peculiar to the Indians, for Mr. Vines and his
  companions, who were intimately conversant with them, and frequently
  lodged in their wigwams, were not in the least degree affected by it,
  though it swept off the Indians at such a prodigious rate that the
  living were not able to bury the dead, and their bones were found
  several years after, lying about the villages where they had resided.
  The extent of this pestilence was between Penobscot in the east,
  and Narraganset in the west. These two tribes escaped, whilst the
  intermediate people were wasted and destroyed.”

  This distemper appears to have raged among the Indians in the year
  1616. The following particulars are further given in Belknap’s
  Biography, vol. ii, p. 208: “Hitherto they (the English colonists)
  had not seen any of the natives at this place. The mortal pestilence
  which raged through the country, four years before, had almost
  depopulated it. One remarkable circumstance attending this pestilence
  was not known till after this settlement was made. A French ship had
  been wrecked on Cape Cod. The men were saved, with their provisions
  and goods. The natives kept their eye on them, till they found an
  opportunity to kill all but three or four, and divide their goods.
  The captives were sent from one tribe to another, as slaves. One of
  them learned so much of their language, as to tell them that God was
  angry with them for their cruelty, and would destroy them, and give
  their country to another people. They answered that they were too
  many for God to kill. He replied, that if they were ever so many,
  God had many ways to kill them, of which they were then ignorant.
  When the pestilence came among them (a _new disease_, probably the
  _yellow fever_) they remembered the Frenchman’s words; and when the
  Plymouth settlers arrived at Cape Cod, the few survivors imagined
  that the other part of his prediction would soon be accomplished.
  Soon after their arrival, the Indian priests or powows convened, and
  performed their incantations in a dark swamp three days successively,
  with a view to curse and destroy the new comers. Had they known the
  mortality which raged among them, they would doubtless have rejoiced
  in the success of their endeavours, and might very easily have taken
  advantage of their weakness to exterminate them. But none of them
  were seen till after the sickness had abated; though some tools,
  which had been left in the woods, were missing, which they had stolen
  in the night.”

  [146] “The Pawkunnawkutts were a great people heretofore. They
  lived to the east and northeast of the Narragansitts, and their
  chief sachem held dominion over divers other petty sagamores; as
  the sagamores upon the island of Nantuckett, and Nope, or Martha’s
  Vineyard, of Nawsett, of Mannamoyk, of Sawkattukett, Nobsquasitt,
  Matakees, and several others, and some of the Nipmucks. Their
  country, for the most part, falls within the jurisdiction of New
  Plymouth colony. This people were a potent nation in former times,
  and could raise, as the most credible and ancient Indians affirm,
  about three thousand men. They held war with the Narragansitts, and
  often joined the Massachusetts as friends and confederates against
  the Narragansitts. This nation, a very great number of them, were
  swept away by an epidemical and unwonted sickness, an. 1612 and 1613,
  about seven or eight years before the English first arrived in those
  parts to settle the colony of New Plymouth. Thereby Divine Providence
  made way for the quiet and peaceable settlement of the English in
  those nations. What this disease was, that so generally and mortally
  swept away, not only these but other Indians, their neighbours, I
  cannot well learn. Doubtless it was some pestilential disease. I have
  discoursed with some old Indians, that were then youths, who say,
  that the bodies all over were exceeding _yellow_ (describing it by a
  yellow garment they showed me) both before they died, and afterward.

  “The Massachusetts, being the next great people northward, inhabited
  principally about that place in Massachusetts bay, where the body
  of the English now dwell. These were a numerous and great people.
  Their chief sachem held dominion over many other petty governors;
  as those of Weechagaskas, Neponsitt, Punkapaog, Nonantum, Nashaway,
  some of the Nipmuck people, as far as Pocomtacuke, as the old men of
  Massachusetts affirmed. This people could, in former times, arm for
  war about three thousand men, as the old Indians declare. They were
  in hostility very often with the Narragansitts, but held amity for
  the most part with the Pawkunnawcutts, who lived on the south border,
  and with the Pawtucketts, who inhabited on their north and northeast
  limits. In an. 1612 and 1613 these people were also sorely smitten
  by the hand of God with the same disease before mentioned; which
  destroyed the most of them, and made room for the English people of
  Massachusetts colony, which people this country, and the next called
  Pawtuckett. There are not of this people left at this day above three
  hundred men, besides women and children.

  “Pawtuckett is the fifth and last great sachemship of Indians. Their
  country lieth north and northeast from the Massachusetts, whose
  dominion reacheth so far as the English jurisdiction, or colony
  of the Massachusetts, doth now extend, and had under them several
  other smaller sagamores; as the Pennakoaks, Agawomes, Naamkeeks,
  Pascatawayes, Accomintas, and others. They were also a considerable
  people heretofore, about three thousand men, and held amity with the
  people of Massachusetts. But these also were almost totally destroyed
  by the great sickness before mentioned; so that at this day they are
  not above two hundred and fifty men, besides women and children.
  This country is now inhabited by the English under the government of
  Massachusetts.” (Gookin’s Historical Collections of the Indians in
  New England.)

  The following was communicated to Benjamin Basset, esq. of Chilmark,
  by Thomas Cooper, a half blooded Indian, of Gay Head, aged about
  sixty years; and which, he says, he obtained of his grandmother, who,
  to use his own expression, was a stout girl when the English came to
  the island: “Before the English came among the Indians, there were
  two disorders of which they generally died, viz. the consumption and
  the yellow fever. The latter they could always _lay_ in the following
  manner: After it had raged and swept off a number, those who were
  well, met to lay it. The rich, that is, such as had a canoe, skins,
  axes, &c. brought them; They took their seat in a circle, and all the
  poor sat around without. The richest then proposed to begin to lay
  the sickness; and, having in his hand something in shape resembling
  his canoe, skin, or whatever his riches were, he threw it up in the
  air; and whoever of the poor without could take it, the property it
  was intended to resemble became for ever transferred to him or her.
  After the rich had thus given away all their moveable property to
  the poor, they looked out the handsomest and most sprightly young
  man in the assembly, and put him into an entire new wigwam, built of
  every thing new for that purpose. They then formed into two files
  at a small distance from each other; one standing in the space at
  each end put fire to the bottom of the wigwam on all parts, and fell
  to singing and dancing. Presently the youth would leap out of the
  flames, and fall down to appearance dead. Him they committed to the
  care of five virgins, prepared for that purpose, to restore to life
  again. The term required for this would be uncertain, from six to
  forty-eight hours, during which time the dance must be kept up. When
  he was restored he would tell, that he had been carried in a large
  thing high up in the air, where he came to a great company of white
  people, with whom he had interceded hard to have the distemper laid,
  and generally, after much persuasion, would obtain a promise, or
  answer of peace, which never failed of laying the distemper.”

  The following is extracted from Prince’s Chronological History of
  New England, p. 46: “This winter (1617) and the spring ensuing, a
  great plague befals the natives in New England, which wasteth them
  exceedingly; and so many thousands of them die, that the living are
  not able to bury them, and their skulls and bones remain above ground
  at the places of their habitations for several years after.

  “By Capt. Dermer’s letter of Dec. 27, 1619, in Purchas, and of
  June 30, 1620, in Gov. Bradford, compared with Gov. Bradford’s own
  account, it seems that the Narragansitts in the west, and Penobscots
  in the east, escaped this plague, or that it raged only in the
  countries lying between them, and prepared the way for another
  people.”

Mr. Webster, in his eighth letter to Dr. Currie on the subject of
pestilential diseases, quotes from the Doctor’s letter to Mr. Wynkoop,
of October 5th, 1797, the following passages: “Thomas Story and Joseph
Gough relate, that a malignant fever prevailed in Philadelphia in 1699,
introduced from the West India islands.... Dr. Mitchill ascribes the
yellow fever as it appeared in Virginia in 1741 and 47 to specific
contagion, and mentions that it had been twice imported into Virginia
by his Majesty’s ships of war. Dr. _Leamy_ (_Lining_) in the Physical
Essays in Edinburgh, informs us, that the yellow fever which has
prevailed at different periods at Charleston, South Carolina, was
always traced to some infected person recently from the West Indies.
In 1741 it was introduced by a chest of wearing apparel which had
belonged to a person who died of it from Barbadoes.” These quotations
are made by Mr. Webster with a view to dispute the contagious nature of
the disease. Here they are introduced only to show if possible the time
that the disease first entered the United States; and the introduction
of it into Philadelphia in 1699 (though we are not sure if even this
was its first appearance), still corresponds extremely well with the
date of its introduction into Martinique mentioned by Sauvages. Dr.
Lining says it had been four times epidemic in Charleston before the
time that he wrote; viz. in 1732, 1739, 1745, and 1748. Hence we may
conclude, that this fever, on the northern part of the continent of
America, has been nearly coeval with the settlement of the British
colonies there; for we cannot suppose that we have accounts of the
very first time that it made its appearance any where. Numbers of
individuals would probably be affected with it, and their cases pass
unnoticed, till the general malady attracted the public attention.

In the Spanish dominions it seems to have been otherwise. Dr. Moseley
quotes Don Ulloa saying that “the _vomito prieto_, or black vomit, was
unknown at Carthagena, and all along the coast, till the years 1729 and
1730. In 1729 Don Domingo Justiniani, commodore of the guarda costas,
lost so considerable a part of his ships’ companies at _Santa Martha_,
that the survivors were struck with astonishment and horror at the
havock made among their comrades. In 1730, when the galleons under Don
Manuel Lopez Pintado came to Carthagena, the seamen were seized with
the same dreadful mortality, and so sudden were the attacks of the
disease, that persons, walking about one day, were the next carried to
their graves. Unhappily, after all the experiments of the surgeons of
the galleons, and physicians of the country, no good method of treating
the disease has been discovered; no specific for curing it.”

This fatal disease, however common in the southern and warm part of the
continent of America, seems not to have exerted its power in the more
northern and temperate climates till the year 1793. Since that time
its ravages have been too well known to require an enumeration here.
To describe the symptoms, inquire into the causes, and the means of
prevention and cure, is a work of more importance, and to this we must
now proceed.



SECTION. II.

  _Symptoms of the Yellow Fever, as described by various
  authors.--Comparison between them and those of the Plague, with an
  inquiry into the Causes.--History of the Distemper as it has appeared
  in various parts of the United States since the year 1793.--A
  discussion of the question Whether the Yellow Fever is Contagious or
  not._


Of all those who have attempted to give an account of this fatal
disease, none appear to have exceeded Dr. Moseley, either in his
accuracy in enumeration, or perspicuity in description, of the
symptoms. According to him the yellow fever is a species of the
_kausos_ of Hippocrates, Aretœus and Galen; that is, the _febris
ardens_ or _causus_, aggravated by climate, incidental only to the
gross, inflammatory and plethoric at any season of the year, totally
different from the remitting bilious fever to which all habits of body
are subject in hot climates, particularly after rains, and in the fall
of the year. The causus, seldom seen in the temperate climates of
Europe, never appears there with the violent symptoms which attend it
in hot climates. “Whether in the latitudes (says he) so mild as those
of Spain, Greece, Italy and the Archipelagan islands, the causus has
ever been attended with black vomiting, as in the West-Indies, I cannot
tell. Lommius mentions the vomiting of blood, and voiding black liquid
stools and black urine. Critical and symptomatical yellowness of the
skin in the causus are enumerated by Hippocrates among its symptoms,
and Lommius mentions the danger of that appearance before the seventh
day. The affinity of the symptoms, progress and termination of a causus
in Europe to those of the yellow fever in the West-Indies, excepting
the black vomiting, leaves no room to doubt that the difference of
climate constitutes all the difference that is found between them.”

For these reasons Dr. Moseley adopts the name of _endemial causus_;
and he takes notice that many difficulties have arisen to young
practitioners, and to strangers in the West-Indies, from the various
names improperly given to it from its ultimate and not from its primary
symptoms. Some call it a _burning_ bilious fever; Warren, a _putrid_
bilious fever; but, though they have disputed about their terms, Dr.
Moseley thinks that neither of them have proved whether bile be the
cause or the effect of the disease. To call it the black vomit or the
yellow fever, he thinks also improper, as a stranger would not know
the disease until some of these symptoms appear; both of which are
generally fatal, and neither of them constant.

The West-India causus he says is no more putrid than the small-pox,
or any other acute disease; which may, after it has passed its
inflammatory state, change to putrefaction, and end in death with an
extraordinary dissolution of the fluids. The disease is in truth an
inflammatory one in the highest degree possible; accompanied with such
symptoms in a greater extent as attend all inflammatory fevers, and
most strikingly the reverse of any disease that is putrid, or of one
exacerbation. It obeys no season of the year, and attacks such people,
and under such circumstances, as are seldom the objects of putrid
diseases, viz. all who are of an inflammatory diathesis, and do not
perspire freely.

This distemper attacks sailors in the West-Indies more than any other
set of men, even of new comers. For this the Dr. assigns as a reason,
that they eat, drink, and sleep, so much at sea, use no exercise,
and are always of gross habit of body. To this he adds the heat and
dampness of harbours, generally in the neighbourhood of marshes, and
their exposure to land winds at night; the labour they endure on board
vessels in port, and the carelessness and excesses frequently committed
by these people after long voyages.

When a stranger newly arrived feels a sudden loss of strength, with
a continual desire of changing his position without finding rest in
any, we may expert a causus. If he has exposed himself to any of the
causes just mentioned, the probable consequences would be, that on the
morrow he would feel an heaviness, lassitude, oppression and loss of
appetite.[147] Next day, or perhaps within twelve hours from the first
indisposition, the violence of the disease commences with faintness,
generally giddiness of the head, with a small degree of chillness and
horror, but never any rigor. These symptoms are succeeded by a high
fever, great heat, and strong beatings of the arteries, particularly
those of the temples and carotids; flushings of the face, gasping for
cool air; tongue white tinged with yellow, after the retchings have
commenced; excessive thirst; redness, heaviness, and sensations of
burning in the eyes; heaviness and darting pains in the head, small
of the back, and often down the thighs; the pulse generally full and
strong, but sometimes quick, low, and vacillating; the skin hot and
dry, though sometimes it has a partial and momentary moisture. There is
a sickness of stomach from the beginning; retchings succeed immediately
after any liquid is swallowed, which bring up bilious matter. There
is an anxiety with stricture, soreness, and intense heat about the
præcordia; great restlessness, heavy respiration, sighing, urine deep
coloured and in small quantity.

  [147] “This (says the Doctor) is the time to extinguish the disease;
  but Europeans and North Americans generally neglect it, as they are
  not accustomed at home to have recourse to medicine on the first
  moment of indisposition.”

Thus the fever goes on during its first stage, which constitutes the
inflammatory period, and continues from twenty-four to sixty hours.
The second, which our author calls the _metaptosis_, is comparatively
mild, and is an intermediate state between the inflammatory and
gangrenous stages. In this there is an abatement of many of the former
symptoms, and a kind of deceitful tranquillity, accompanied, however,
with a perturbation, if the patient should happen to sleep. There now
appears a yellow tinge in the eyes, neck and breast; the heat subsides,
sometimes accompanied with chillness, but never with that kind of
rigor, which, when it happens, terminates the disease by sweat, or
by copious bilious evacuations, upwards or downwards. The retchings
increase and become porraceous: the pulse flags, but is sometimes
high, and sometimes soft; the skin moist and clammy; urine of a dark
saffron colour, and in small quantity; the tongue in some cases is
dry, hard, and discoloured, in others furred and moist; the head is
confused, sometimes with delirium, with a glossiness of the eyes. This
stage of the disease continues sometimes only for a few hours, at
others from twelve to forty-eight, seldom longer, and too frequently
the disease hurries on rapidly from the first to the third stage, which
is the gangrenous or fatal state. Now the pulse sinks, intermits, and
becomes unequal, sometimes very quick; the vomiting becomes frequent
with great straining and noise. The matter discharged is now in greater
quantity, appearing like the grounds of coffee, or of a slate colour,
and the stomach can retain nothing: the breathing is difficult, the
tongue black, the sweats cold and clammy, the eyes yellow and sunk;
there is a yellowness round the mouth and temples, and soon after
over the whole body. The deepening of the yellow colour, with an
aggravation of the other symptoms, is a forerunner of death. There is
a deep respiration, subsultus tendinum, a convulsive kind of sighing;
the urine is quite black, and sometimes totally suppressed. There is a
death-like coldness of the hands, feet and legs, while the heat still
remains about the stomach; the patient is delirious, and struggles to
get up in bed; he trembles, his speech falters; blood oozes from the
mouth and nostrils, sometimes from the corners of the eyes and ears; a
black bloody cruor is discharged both by vomit and stool: livid spots
appear on different parts of the body, particularly the præcordia;
hiccup, muttering, coma, and death, follow in quick succession.

The affecting case of capt. Mawhood, who died on the fourth day of
the disease, at Port-Royal in Jamaica, in the year 1780, exhibits a
dreadful picture of this disease in its last stage. “When I entered
the room, (says Dr. Moseley) he was vomiting a black, bloody cruor,
and he was bleeding at the nose. A bloody ichor was oozing from
the corners of his eyes, and from his mouth and gums. His face was
besmeared with blood, and with the dullness of his eyes it presented
a most distressing contrast to his natural visage. His abdomen was
swelled and inflated most prodigiously. His body was all over of a deep
yellow, interspersed with livid spots. His hands and feet were of a
livid hue. Every part of him was cold, excepting about his heart. He
had a deep, strong hiccup, but neither delirium nor coma; and was, at
my first seeing him, as I thought, in his perfect senses. He looked
at the changed appearance of his skin, and expressed, though he could
not speak, by his sad countenance, that he knew life was soon to yield
up her citadel, now abandoning the rest of his body. Exhausted with
vomiting, he was at last suffocated with the blood he was endeavouring
to bring up, and expired.”

The symptoms just now enumerated generally take place in those who
die from the third to the seventh day of the disease. But in this,
as in other fevers, the symptoms vary considerably according to the
constitution of the patient, and habit of the body. In some it begins
neither with chillness, faintness, nor flushings of the face. Sometimes
the pulse is much depressed and not quick; and in sultry weather,
and damp situations, where the inflammatory state has been only of
a few hours duration, the _metaptosis_ has been so rapid, that the
black vomiting and the mortified state have unexpectedly appeared,
and have ended the patient in 24, 36 or 48 hours. But our author says
that he never saw or heard of an instance of what Lind says, that the
black vomit may attack a man when newly arrived, without any previous
complaint; or of that mentioned by the same author, viz. “an uneasy
itching sensation, commonly in the legs; and upon pulling down the
stockings, streams of thin-dissolved blood followed, and a ghastly
yellow colour quickly diffused itself all over the body.”

In some cases the disease is much more mild. There are instances where
it has been protracted to the eighth, ninth or tenth day; and others
where it has never passed from the inflammatory stage; but being
checked, though not extinguished, it has been lengthened out, and at
last converted into a remittent of great duration, most difficult of
cure, and tedious of recovery.

According to our author, the stomach seems to bear the principal burden
of the disease, and accordingly, after death, appears to have been
principally affected. Great heat is perceived near the præcordia during
all the stages of the disease, and pain and uneasiness are complained
of when those parts are pressed with the hand. After death, livid
spots appear over the whole body, particularly about the præcordia.
On dissection, the stomach, in some part or other, is generally found
mortified, especially if the black vomiting has continued long, and the
livid spots have appeared before death. Frequently the upper part of
the duodenum is in a gangrenous state, and always bears the marks of
inflammation, lest the disease have been of ever so short a duration.

Though both liver and gall-bladder must be very much affected in this
disease, yet Dr. Moseley is of opinion that nothing can be depended
upon from an inspection of them after death. Some symptoms there are
in common with inflammations of the liver, but none of those which
distinguish it from other diseases. It never terminates in suppuration
of the liver as the hepatitis sometimes does, though it is frequently
carried off by an enormous secretion of bile. “Dissections (says the
Doctor) have never discovered any certain and uniform appearance in the
liver of those who have died of this disease. In hot climates a sound
state of the liver is never to be expected after death, whether the
disease has been acute or chronical. Of the latter class of diseases it
is almost always either the seat, or the origin.”

Dr. Lining, in a letter to Dr. Whytt at Edinburgh, published in the
Physical and Literary Essays, defines the disease, to be “that fever,
which continues two or three days, and terminates without any critical
discharge by sweat, urine, stool, &c. leaving the patient excessively
weak, with a small pulse, easily depressible by very little motion, or
by an erect posture; and _which_ is soon succeeded by an icteritious
(jaundice) colour in the white of the eyes and the skin; vomiting,
hæmorrhages, &c. and those without being accompanied with any degree of
a febrile pulse and heat.”

In the four times in which he mentions it to have been epidemic at
Charleston, our author says, that none of the years (excepting 1739,
the summer and autumn of which had been remarkably rainy) were either
warmer or more rainy (and some of them less so) than the summers and
autumns were in several other years in which there was not one instance
of any one being seized with it. The subjects were whites of both
sexes, especially strangers lately arrived from cold climates, Indians,
Mistees, Mulattoes of all ages, excepting young children, and of those
only such as had formerly escaped the infection. Negroes were not
liable to it.

Those affected with the fever, for a day or two previous to the attack
generally complained of head-ach, pain in the loins and extremities,
but principally in the knees and legs, debility and lassitude; but
some were taken ill suddenly without any warning. The symptoms were,
shivering; frequent, full, hard and strong pulse; though sometimes
small and hard, and in others soft and small; but towards the end of
the fever it became smaller, harder, and less frequent. Sometimes there
was a remarkable throbbing in the hypochondria and carotids, the former
causing in some a tremulous motion of the whole abdomen. The heat was
about 102 of Fahrenheit, and nearly equal over the whole body; some had
frequent returns of chilliness without any diminution of temperature of
the body. “In a few there happened so great a remission of the heat for
some hours, when at the same time the pulse was soft and less frequent,
and the skin moist, that one from these circumstances might reasonably
have hoped that the fever would only prove a remittent or intermittent.
About the end of the second day the heat began to abate.” Here Dr.
Moseley takes notice that when the fever abates, some, who have
mistaken the _bilious remittent_ for the _causus_, speak of remissions
which do not happen in this fever. “This circumstance of the endemial
causus (says he) I believe, has never been mentioned before.”

Dr. Lining goes on to inform us, that the skin was rarely dry in this
disease, there being generally a propensity to sweat. “On the first day
the sweating was commonly profuse and general, on the second it was
more moderate; but on both those, there happened frequent and short
remissions of the sweatings, at which times the febrile heat increased,
and the patient became more uneasy. On the third day the disposition
to sweat was so much abated that the skin was generally dry; only the
forehead and backs of the hands continued moist.” A great despondency
and prostration of strength took place from the first attack. On the
first day they generally dozed much, but were afterwards very watchful.
On the second day the pains in the head, loins, &c. of which they had
complained before the attack, and which were sometimes very acute in
the forehead, generally went off. Many on the first day were a little
delirious, but afterwards not until the recess of the fever.

The blood had no inflammatory crust; in warm weather it was florid
like arterial blood, and continued in one soft homogeneous like mass,
without any separation of the serum after it was cold. When there was
any separation, the crassamentum was of too loose a texture.

This disease was not attended with any remarkable thirst; but, on the
third day, as the fever began to lessen, or rather, says the Doctor,
as the fulness of the pulse, heat and disposition to sweat, began to
abate, a nausea, vomiting, or frequent reachings to vomit, came on
especially after the exhibition of either medicines or food. A very few
had a vomiting, either bilious or phlegmatic, on the first day. The
whole febrile state was attended with an obstinate costiveness.

These were the principal symptoms with which the febrile state was
attended, and which generally went off on the third day, or in
seventy-two hours from the first attack, without any salutary crisis,
and was soon succeeded by the second _stadium_, as our author calls it;
a state, though without a fever, much more terrible than the former.
The symptoms now were,

1. The pulse, though hard and small, became less frequent; very little
more so than in health. Soon after it became much slower, and very
soft; this softness remaining while any pulse could be felt. In many it
gradually subsided, till it became scarce perceptible; neither could
it be supported by any of the ordinary means used for that purpose.
After this the yellow suffusion, the vomiting, delirium, restlessness,
&c. increased to a great degree. Sometimes the pulse would recover its
strength, but only for a short time.

2. The heat did not exceed the natural, and was still farther
diminished as the pulse sunk; the skin became cold, and the face,
breast and extremities acquired something of a livid colour. There was
no great thirst, though the sick had a great inclination for strong
liquors.

3. The vomiting or reaching to vomit increased, and in some were so
constant, that neither medicines nor aliment of any kind could be
retained. Some vomited blood, others only what was last exhibited,
mixed with phlegm, while others had what is called the _black vomit_.
But this, though its general appearance is black, appears not to be
entirely so, but owes its colour to a great number of black flakey
substances. These are by our author supposed to be the bile mixed with
the mucus of the stomach, or adhering to it. He founds his opinion upon
observations from dissection, where the mucus of the stomach was always
found abraded, and the bile in its cystis black, and sometimes very
viscid. This change in the state of the bile he has always observed
in such as died of this disease, and likewise that the blood was very
fluid, and the vessels of the viscera much distended. In one case he
found the bile of the consistence of turpentine, and carbuncles or
gangrenous specks on the stomach.

The reaching to vomit continued a longer or shorter time, according
to the state of the pulse; an increase of fulness of the pulse being
attended with an abatement of the reaching, and the contrary.

In this state the patients were extremely unquiet, even their sleep
being frequently attended with dejection of spirits and debility. This
last symptom was so excessive that if the patient was only raised
up in bed, or sometimes if the head was only raised from the pillow,
while a little drink was given, the pulse sunk immediately, and became
sometimes so small, that it could scarce be felt: they became cold,
the skin became clammy, the delirium increased, their lips and skin,
especially about the neck, face and extremities, as well as the nails,
acquired a livid colour. The restlessness and tossing were so great,
that it was sometimes scarce possible to keep the sick in bed, though,
even in this state, they made no particular complaint, and if asked how
they did, the reply was, _Very well_.

A yellowness in the eyes became now very observable, and this was
soon diffused all over the body; but in some, this colour did not
appear until a little before death, when it spread surprisingly quick,
especially about the breast and neck. Along with this were a number
of small spots of a scarlet, purple or livid colour. These appeared
principally about the neck and breast.

Some were obstinately costive, others the contrary, with large, liquid
and black stools, but others were relieved by moderate stools, even
though black. In some they resembled tar, in smoothness, tenacity,
colour and consistence.

In this disease there was such a putrid dissolution of the blood that
hæmorrhages took place from almost all parts of the body. In women
the menstrua flowed, sometimes in great quantity, even at irregular
periods. Blood flowed also from the eyes, nose, mouth and ears, and
from those parts where blisters had been laid on. “Nay, (says our
author) in the year 1739 or 1745, there were one or two instances of an
hæmorrhage from the skin, without any apparent puncture, or any loss of
the scarf-skin.” The urine was pale while the patient was not yellow,
but a deep saffron colour when the yellowness had come on. Sometimes it
was turbid, at others bloody, and the quantity of blood was always in
proportion to the state of the pulse; diminishing as the pulse became
more full, and increasing as it became weaker.

In the third stage, which always terminated in death, the pulse was
exceedingly small and unequal, though soft; the extremities were cold,
clammy and livid; the face and lips in some flushed, in others they
were of a livid colour; the livid specks increased so fast, that in
some the whole breast and neck appeared livid; the heart palpitated
strongly; the heat about the præcordia was greatly increased,
respiration became difficult, with frequent sighing; the patient became
anxious and extremely restless, the sweat flowed from the face, neck
and breast, blood from the mouth or nose or ears, and in some from
all together; the deglutition became difficult, hiccup and subsultus
tendinum came on, the patient picked the bed-clothes, was comatous or
constantly delirious. In this terrible state some continued eight, ten
or twelve hours before they died, even after they had been so long
speechless, and without any perceptible pulsation of the arteries and
wrists; whereas in all other acute diseases, death follows immediately
after the pulse in the wrists ceases. When the disease was very acute,
violent convulsions seized the unhappy patient, and quickly brought
this stadium to its fatal end. After death the livid blotches increased
fast, especially about the face, neck and breast, and the putrefaction
began very early, or rather increased very quickly. In hot weather,
and when the symptoms at first were very violent, there was little
difference to be observed between the stadia, the whole tragedy being
completed in less than forty-eight hours.

On this disease in general Dr. Lining remarks, that the infection was
increased by warm, and lessened by cold, weather. In hot days the
violence of the symptoms were augmented to such a degree as sometimes
to become fatal to those who, in moderate weather, seemed to be in no
danger; while, on the other hand, in cold days, some who had been in
great danger were apparently saved from the jaws of death. The disease
was also more fatal to those who lay in small chambers without a
proper ventilation, to such as were of an athletic and full habit, to
strangers, natives of a cold climate, and to such as were most afraid
of it, as well as to those who had previously overheated themselves
by exercise in the sun, or by excessive drinking of strong liquors. It
proved also most certainly fatal to valetudinarians, or to such as had
been previously weakened by any disease.

Dr. Lind observes that “a yellow colour of the skin is observed not
only in common agues, but likewise in other fevers; sometimes denoting,
as in contagious fevers, their malignant nature, at other times, as
in some West Indian fevers, an universal dissolution of the blood and
humours; and frequently this symptom accompanies gentle discharges of
the bile, and a diseased liver.” In speaking of the disease in the West
Indies, he mentions some fevers, which he derives from stagnated air,
“of such a malignant nature, that the people after being there a few
days are suddenly seized with violent vomitings, head-achs, deliriums,
&c. and in two or three days more the whole body putrefies, and the
dissolved mass of blood issues from every pore.... On considering
the yellow fever particularly he is of opinion that the remarkable
dissolution of the blood, together with the tendency to putrefaction in
the whole body, the black vomit, and other characteristic symptoms, are
often accidental though fatal appearances in fevers of the West Indies.
They proceed, according to him, in such as are newly arrived, sometimes
from a gross habit of body, excessive drinking of spiritous liquors,
and from being afterwards overheated in the sun; but the intense heat
and unhealthfulness of the air does much more frequently produce
all those symptoms. This fever was once supposed to have been first
carried into the West Indies by a ship from Siam: _an opinion truly
chimerical_; as similar diseases have made their appearance, not only
in the East Indies, but in some of the southern parts of Europe, during
a season when the air was intensely hot and unwholesome. This happened
in the months of September and October 1764, when excessive heat and
want of rain for some months gave rise to violent epidemic bilious
diseases, resembling those of the West Indies, in the city of Cadiz in
Spain, of which an hundred persons often died in a day. At this time
the winds blew mostly from the south, and after sunset there fell an
unusual and very heavy dew. The disease began with alternate heats and
chills, nausea, pains of the head, back, and loins, and at the pit of
the stomach, These symptoms were often followed, in less than 24 hours,
with violent reachings, and a vomiting of green and yellow bile, the
smell of which was very offensive. Some threw up an humour as black as
ink, and died soon after, in violent convulsions and in a cold sweat.
The pulse was sometimes sunk, sometimes quick, but often varying. After
the first day, the surface of the body was generally either cold, or
dry and parched. The head-ach and stupor often ended in a furious
delirium, which quickly proved fatal. The dead bodies having been
examined by order of the court of Madrid, the stomach, mesentery and
intestines were found covered with gangrenous spots. The orifice of the
stomach appeared to have been greatly affected, the spots upon it being
ulcerated. The liver and lungs were both of a putrid colour and texture.

“The stomach contained a quantity of an atrabilious liquor, which, when
poured on the ground, produced a sensible effervescence; but, when
mixed with spirit of vitriol, a violent ebullition ensued. The dead
bodies turned so quickly putrid, that at the end of six hours their
stench was intolerable, and in some of them worms were already found
lodged in the stomach. His Majesty’s ship the Tweed being at that time
in Cadiz bay, several of her men were taken ill when on shore, but, by
being carried on board, all of them recovered. Neither did the black
vomit or any other deadly symptom of that fever make its appearance
in any of the ships. The dread of this distemper forced many people
of fashion to retire into the country, where they remained in perfect
safety.”

Dr. Lind further remarks, that in the yellow fever it is a bad sign if
the skin is very dry and rough; “and the longer it continues in this
state, the greater is the danger, as such patients seldom recover,
though the pulse may give hopes, and the other symptoms also be
fluttering; for many have a good pulse in this fever a little before
death.” He also quotes Dr. Bruce, an eminent physician of Barbadoes,
whose account of the disease is to the same purpose. He says it may
come on at any season of the year, but that the symptoms are most
severe when there is great heat joined with moisture. The blood, even
in the beginning of the disease, is of a florid red colour, and as
it were rarefied; the crassamentum scarcely cohering; the serum of a
clay-coloured yellow. It sometimes finishes its course in 24 hours.

The account given by Dr. Hillary corresponds also very much with that
already given. The subjects of the disease are the same with those
already mentioned. He has seen it at all seasons of the year, but it
is worst in a hot season, especially if it was preceded by moist and
warm weather. “Blood, taken even at the beginning of the disease, is
often of an exceeding florid red colour, much rarefied and thin, and
without the least appearance of fiziness; and the crassamentum, when
it has stood till it is cold, will scarce cohere, but fluctuates; the
serum is very yellow.... On the second or third day the blood is much
more dissolved, the serum more yellow, and the crassamentum loose,
scarcely cohering, but undulates like sizy water when shaken, and
sometimes has dark, blackish spots on its surface, showing a strong
gangrenescent diathesis.... In the latter stage of this fever the blood
is so attenuated and dissolved, that we frequently see it flowing not
only out of the nose and mouth, but from the eyes, and even through the
very pores of the skin; also great quantities of black, half-baked,
half-mortified blood is frequently voided, both by vomiting and
stool, with great quantities of yellow and blackish putrid bile, by
the same ways; and the urine, which was before of a high icteritious
colour, is now almost black, and is frequently mixed with a quantity
of half-dissolved blood.... Soon after death the body appears much
fuller of livid, large, blackish, mortified spots, particularly about
the præcordia and hypocondres, especially the right; which parts seem
to be, even from the first seizure, the principal seat of this terrible
disease. And upon opening the bodies of those who die of it, we
generally find the gall-bladder and biliary ducts filled with a putrid
blackish bile, and the liver and stomach, and adjoining parts, full
of blackish and mortified spots, and sometimes gangrenes, in those,
as also in several other parts of the body. And the whole corpse soon
putrefies after death, and can be kept but a few hours above ground.”

Dr. Jackson, in describing the yellow fever of Jamaica, acknowledges
the difficulty of characterising the disease, even though he is of
opinion that it “possesses some characteristics of its own, different
from those of any other.” In a note at the end of his work, he
observes the impropriety of calling it the _yellow_ fever; because
that yellowness sometimes does not appear at all; and in no one case
does it ordinarily show itself till the latter stages. “I know also
(says he) that most of the practitioners of Jamaica consider it only
as an aggravated species of the remittent, the common endemic of hot
climates. It appeared to me, I must confess, in a different light....
It may not, however, be improper here to take notice of the opinion of
Dr. Moseley, who has endeavoured to persuade us that it is no other
than the _kausos_, or ardent fever, of the ancients. But the yellow
fever of the West Indies is, by Dr. Moseley’s own confession, in some
measure peculiar to strangers newly arrived in tropical climates.
The _kausos_, we are informed, made its appearance in the islands
of the Archipelago, and on the coasts of the contiguous continents,
indiscriminately among men and women, natives and foreigners: in fact
it has not, as far as I can perceive, any claim to be considered
as a distinct disease. If I rightly understand Hippocrates, or the
description of the still more accurate Aretæus, _kausos_ in reality is
only an accidental condition of the common endemic of the country,
where the force of the fever is chiefly exerted upon the stomach and
alimentary canal. In this manner it appears frequently in Jamaica, and
in the southern provinces of America. In the hot months of summer,
it appears occasionally in every climate; and is not necessarily
accompanied with, nor does it depend upon, a general inflammatory
diathesis of the system for its existence.”

The Doctor divides this disease into three species: 1. Where “signs
of putrefaction are evident at a very early stage, which is generally
rapid in its course, and which casually terminates in black vomiting.
Yellowness seldom or never fails to make its appearance in the present
instance; and perhaps it is the only one which, strictly speaking,
can be called the yellow fever. 2. A form of fever which has either
no remissions, or remissions which are scarcely perceptible; in
which signs of nervous affection are more obvious than symptoms of
putrescency; and in which yellowness and black vomiting are rare
occurrences. 3. Another form, in which regular paroxysms and remissions
cannot be traced, but in which there are marks of violent irritation,
and appearances of inflammatory diathesis in the earlier stage,
which give way, after a short continuance, to signs of debility and
putrescency, to which yellowness frequently succeeds, or even sometimes
the so much dreaded vomiting of matter of a dark colour. The disease
in these three forms appears to be in reality one and the same. The
difference of the symptoms probably arises from very trivial or very
accidental causes. It is in some measure peculiar to strangers from
colder regions soon after their arrival in the West Indies, and may
generally be distinguished from the common endemic of the country, not
only by a total want of paroxysms and remissions, but likewise by a
certain expression of the eye and countenance, with something unusually
disagreeable in the feelings, of which words convey only an imperfect
idea.”

The symptoms enumerated by Dr. Jackson are in general the same with
those already taken notice of. He mentions likewise a degree of
confusion frequently joined with _grimness_, difficult to be described
in words, but which a person acquainted with the appearances of the
disease immediately recognises as one of its distinguishing marks. In
the second stage he says, that no sweat or moisture was now observable
on any part of the body: the state of the skin impressed the idea as if
it were not pervious to any degree of perspiration, and heat gradually
forsook the surface and extremities: the tongue became moist, and at
the same time frequently clean about the edges: the gums became redder,
more spongy, and showed a greater disposition to bleed: vomiting
was troublesome: the matter thrown up was ropy, in large quantity,
and abounding with villous or mucous flakes of a darker colour. The
circulation in the extreme vessels became gradually more languid; the
natural heat retired from the surface of the body, which was now dry
and impervious; the pulse returned nearly to its ordinary state, or
became slow, full and regular; the yellowness increased fast, so that
the whole body was frequently yellow as an orange, or of as deep a
colour as the skin of an American savage: anxiety was inexpressible;
vomiting was irrestrainable, and the vomiting of a matter like the
grounds of coffee at last made its appearance. This matter was often as
black as soot, where the progress of the disease had been rapid; while
it was not only less intensely black, but often tinged with green,
where the disease had been more slow and gradual. The number of villous
or mucous flakes, in the matter discharged by vomit, increased as the
disease advanced, and with them were joined streaks of blood, which
seemed principally to come from the throat and gums. As the disease
advanced, the vomiting became more frequent, but was seldom accompanied
with any violent retching. Quantities of liquor were discharged, so
enormous that it was often difficult to imagine whence they came; after
which the patient enjoyed some respite, till a similar collection was
made. As soon as the matter discharged by vomit acquired this dark
and sooty colour, the belly generally became loose, the stools being
black, smooth, and not unlike tar or molasses; the tongue became
clean, the gums putrid; hæmorrhages, or rather _oozings of blood_, were
sometimes observed in different parts of the body, while livid blotches
made their appearance on the belly and insides of the thighs. The
pulse, which during the latter stages of the distemper could scarcely
be distinguished from that of a person in health, became at last
irregular, quick, or intermitting; soon after which coma or convulsions
closed the scene. Sometimes the yellowness succeeded the black
vomiting. In these the vomiting began unexpectedly, or without much
previous affection of the stomach: the colour was commonly intensely
black; the patient turned yellow almost in an instant, and died in a
very short time. When any one recovered from this deplorable situation,
of which there were some few instances, the termination was not by any
regular crisis. The black vomiting ceased, sometimes apparently in
consequence of treatment, sometimes evidently of its own accord: but a
vomiting of a ropy, glutinous matter continued for a great length of
time, together with an extreme irritability of the stomach, and a very
peculiar state of the skin; which sometimes did not recover its natural
smoothness and unctuosity for several weeks.

The disposition to faint, so common in the yellow fever, is supposed
by Dr. Jackson to arise from a kind of torpor in the nervous system,
rather than the usual causes of fainting. For this opinion he assigns
as a reason, that “the patient was often able to stand upright for
some time, and even to walk to a considerable distance; and, when at
last overcome, was observed to fall down in a torpid, rather than a
fainting, state.”

In dissections our author observed that the omentum and all its
appendages were in a dry and parched state, and of an uncommon dark
grey colour. But, along with this dark grey colour, and want of
unctuosity and moisture, usually met with in the abdomen, the stomach
and intestines had a dirty yellow appearance, were highly putrefied,
and much distended with wind. The liver and spleen were generally
enlarged in size; the former of a deeper yellow than any of the other
abdominal viscera; while the texture of the spleen was often less
firm than natural. The bile was usually black and thick, like tar or
molasses; the blood-vessels of the liver bearing marks of uncommon
distension. A quantity of black fluid, similar to that ejected by
vomit, was found in the stomach, which fluid our author says positively
derived its blackness from the bile, the flakes observed to float in
it being parts of the villous coat of the stomach abraded. He denies
that the black colour of the matter vomited is owing to blood, as many
authors have supposed. He says that the passage of the bile might be
easily traced from the gall-duct into the pylorus.

This being in the Doctor’s opinion the only true kind of yellow
fever, we shall not follow him through the description of the other
two species, but proceed to consider that remarkable and excessively
fatal distemper which appeared in the year 1793, first in the West
India islands, and then on the American continent. Dr. Chisholm, who
has described the distemper very particularly, derives it from the
coast of Africa, and gives the following account of its origin on the
authority of a Mr. J. Paiba, “one of the adventurers in the Boullam
scheme; and who, despairing of success, left the coast of Africa in
a vessel called the _Hankey_. This vessel sailed from England in
April 1792 with stores and adventurers for the intended colony at
Boullam. The people were all in good health: that part of the coast
of Africa on which they touched is remarkable for its healthiness;
only it is destitute of water except what can be procured by digging
temporary wells on the beach, and which is brackish, and consequently
unwholesome. The ferocity of the negroes who inhabit that part of the
continent prevented them from being accommodated on shore, so that they
found themselves obliged to remain on board the Hankey for nine months.
As the rainy season came on almost immediately after their arrival on
the African coast, they attempted to shelter themselves by raising the
sides of the vessel several feet, and covering it with a wooden roof.”
Thus were upwards of two hundred persons, among whom were many women
and children, confined in such a manner as must be supposed capable
of producing fevers of a bad kind, if they could be produced by such
causes. Accordingly a malignant fever did break out; the vessel was not
ventilated, nor were the bed-clothes, &c. of the sick destroyed; from
whence Dr. Chisholm concludes that the infection remained on board the
vessel. The Doctor then proceeds to give the following account of the
vessel after her departure from Boullam:[148] “Capt. Coxe, finding the
water at Boullam unwholesome, proceeded with his ship to Bissao, where
there is a Portuguese settlement, for a supply. The ship was navigated
by about twelve seamen, most of whom had not experienced sickness, and
had probably been procured from Sierra Leone: at any rate they were
then taken on board for the first time. Of these, before the return of
the Hankey to Boullam, nine died; and the remainder, with the captain,
were reduced to a deplorable state. The time for which the Hankey was
chartered being expired, Mr. Paiba, with his family, intended to return
to England in her; but as no seamen could be procured they put to sea,
having on board the captain, sick, and only the mate, Mr. Paiba and
two seamen to navigate the ship. With much difficulty they arrived at
St. Jago, where they fortunately found the Charon and Scorpion ships
of war. Capt. Dodd of the former, humanely rendered them every service
in his power, and on leaving them put two men of each ship on board
the Hankey. With this aid they proceeded to the West Indies; a voyage
to England being impracticable in their wretched state. On the third
day after leaving St. Jago, the men they procured from the ships of
war were seized with the fever, which had carried off three fourths
of those on board the Hankey at Boullam; and, having no assistance,
two of the four died: the remaining two were put on board here in the
most wretched state possible. Capt. Dodd, on his arrival at Barbadoes
from the coast of Africa, was ordered to convoy the homeward-bound
fleet of merchantmen. In the execution of his orders he came to Grenada
on the 27th of May, and, hearing of the mischief which the Hankey
had been the cause of, mentioned that several of the Charon’s and
Scorpion’s people were sent on board the Hankey at St. Jago, to repair
her rigging, &c. that from this circumstance, and the communication
which his barge’s crew had with that ship, the pestilence was brought
on board both ships; and that of the Charon’s crew thirty died, and of
the Scorpion’s, about fifteen. The Hankey arrived at the port of St.
George’s (in Grenada) on the 19th of February, in the most distressed
situation, and for a few days lay in the bay, but was afterwards
brought into the careenage. From this period are we to date the
commencement of a disease before, I believe, unknown in this country,
and certainly unequalled in its destructive nature.”

  [148] Chisholm’s Essay on the Malignant Pestilential Fever, p. 86.

This account of the introduction of the fever (which however is
by Dr. Chisholm accounted very different from the yellow fever
above described) is so clear and distinct, that, at first reading,
it commands our belief. It hath not, however, met with universal
approbation; and even the _facts_, for which both parties appeal to Mr.
Paiba and capt. Dodd, vary from one another in a surprising manner. Dr.
Trotter, in his Medicina Nautica, p. 328, gives the following account:
“Dr. Chisholm tells us, that the ships of war on the African station,
having sent men to assist the Hankey, after numbers had perished from
the fever, received the infection by means of this communication,
and that in the Charon thirty died, and fifteen in the Scorpion.
Capt. Dodd, who at that time had his broad pendant in the Charon, now
commands the Atlas of 98 guns in the fleet; Mr. Smithers, the surgeon,
is at present in the Formidable, a second rate, also in the fleet;
_from them_ I have copied the following narrative of their transactions
with the Hankey:

“When the squadron under commodore Dodd came to St. Jago in 1793, the
Hankey lay there in great distress for want of hands; having buried
above one hundred persons, men, women and children, from the time she
had been at Bulam. _The fever was now overcome_: Mr. Smithers saw two
men that had lately recovered. He left a quantity of bark. The Charon
and Scorpion sent two men each to assist in navigating her to the West
Indies. The Hankey at this port was cleaned, washed with vinegar,
and fumigated. _No fever appeared in either of the men of war_, in
consequence of this communication; they arrived at Grenada in perfect
health, but did not go into the same part of the island to which the
Hankey went. The Charon, at this harbour received some seamen from the
merchant ships then taking in cargoes for England; she had afterwards
_fourteen_ cases of yellow fever, of which one died; but it is
remarkable that the Scorpion did not bury a single man during the whole
voyage.[149] It is probable from these facts, that the Hankey _did not_
import the infection that produced the Grenada fever; for, _after the
disease was worn out_, she had a passage to make to the West indies of
many hundred leagues. It is also doubtful how the effects left in the
Hankey could produce the fever, for the _bedding was thrown away_, and
what clothing remained had been aired, and probably had scarcely been
in contact with the body after being sick.”

  [149] To this is subjoined the attestation of Mr. Smithers with
  respect to the Charon.

The discordance between this and the foregoing account is abundantly
evident. Dr. Chisholm’s account of the bedding, &c. is also very
different. “Our lieutenant governor, Ninian Home, esq. some time after
the disease became epidemic, informed me, that, in consequence of the
information he had received of the clothes, &c. of the victims of the
fever at Boullam being still on board the Hankey, he ordered Capt. Coxe
to be brought before him and some gentlemen of the council. He then
acknowledged, that _all the effects_ of those who had died were then
on board his ship, and said that he _would not_ destroy them, unless
he was indemnified for the loss he might sustain, should the heirs of
the deceased call on him for those effects. Every argument was used to
induce him to destroy the articles, but the only one which influences
a man of this description, _indemnification_; and he of course carried
the seminium of the disease to England.” It was this consideration
which induced the governor to write to the secretary of state, and in
consequence of his representation the vessel was obliged to perform
quarantine in England, a circumstance which Dr. Trotter mentions
without approbation.

Thus far the matter of _fact_ seems to be very much obscured; and
the more we investigate, the more we are involved in darkness. In
the Medical Repository, vol. i, p. 484, we find the following severe
censure passed upon Dr. Chisholm by the late Dr. Smith of New York: “It
belongs to another part of this paper to assign the probable motives of
Dr. Chisholm for maintaining that the fever was imported into Grenada:
certain it is that he avowed a different opinion to Mr. Paiba, to whom
he freely declared, that he could by no means trace the disease to the
_Hankey_; and that he believed it to be of local origin, owing to the
unhealthy condition of the careenage, and the particular prevailing
winds: and, to confirm this notion, he informed Mr. Paiba that a
similar disease, from the same cause, though in a less degree, had
existed in St. George’s some years before.”

This was plainly giving Dr. Chisholm _the lie_; which, whatever
might have been the consequence between the two parties, absolutely
supersedes, to any impartial and unconcerned person, the evidence of
_both_, at least as far as regards the origin of this disease. It
is not, however, to be supposed that Dr. Chisholm would pass such a
censure unnoticed. He did accordingly reply in a letter to Dr. Smith,
who had sent him a copy of the Repository, with a letter inviting
him to defend what he had said. Dr. Smith died before this letter
reached him, but the principal part has appeared in the Medical
Repository, vol. ii, p. 285. In this Dr. Chisholm retracts what he
had said concerning the mortality on board the Charon and Scorpion
ships of war. “I have lately received (says he) from a gentleman of
the navy here, a log-book of the Charon, kept by one of her officers
during the voyage in question. In this I find, that no sickness took
place in either of these ships in consequence of this interview. A
log-book is unquestionable evidence, and I therefore admit it.” As
to the more serious part of the charge, viz. that Dr. Chisholm had
wilfully misrepresented matters, the Doctor replies, that the narrative
published by him was in general such as he had from Mr. Paiba; not
indeed in manuscript, as Dr. Smith stated his to have been, but in
conversation; and that this conversation took place expressly with
a view to elucidate the cause of the fever, which he (Dr. Chisholm)
could not account for by any reasoning from local causes, but heard it
very generally ascribed to infection from the Hankey. Mr. Paiba was
introduced to Dr. Chisholm at the request of the latter by the Hon.
Samuel Mitchill _now_ (the letter is dated Sept. 6th 1768 probably
1798) the senior member of the council of Grenada. “Mr. Mitchill (says
the Doctor) brought Mr. Paiba to my house, and was present during the
greatest part of the time the conversation continued. I found Mr. Paiba
very willing to give me every information in his power relative to the
state of the Bulama or Boulam colony, and of the ship Hankey; but I
found him strongly disinclined to fall in with the universally received
opinion, that that ship introduced the disease. The particulars I have
given, are those Mr. Paiba related to me in this conversation; and, in
order to be correct, I immediately, after Mr. Paiba left me, committed
them to paper. Mr. Paiba promised to favour me with a written account;
and in order to direct that gentleman’s attention to the points I
considered as of most importance, I drew up a set of queries, and Mr.
Mitchill charged himself with the delivery of it. A copy of these I
have now in my possession, and a slight attention will exhibit my
view in framing them, and show the doubts respecting the nature of
the epidemic which suggested them. Although I repeatedly, through Mr.
Mitchill and Mr. Palmer, the gentlemen with whom Mr. Paiba resided
in the country, renewed my request to have this promise fulfilled,
Mr. Paiba left the Island without gratifying it. If no other strong
proof existed of something peculiar in the fever which at that time
prevailed, the circumstance of my formally applying to Mr. Paiba for
information relative to the state of the Hankey, and of taking the
trouble to obtain an interview with him, presents an evidence as
conclusive as can well be required by reasonable men. But the belief
of the infection of the Hankey was _universal_, nor was it by any
means confined to those whose interest might have been affected by the
prosperity of an infant colony on the coast of Africa.”

Another charge against Dr. Chisholm is, that he falsifies the date
of the Hankey’s arrival at Grenada; and which in Dr. Smith’s paper
is brought forward in the following words: “In p. 91 the Doctor
remarks, that, ‘in the short space of time from the beginning of March
to the end of May, 200 of about 500 sailors, who manned the ships
in the regular trade, died of this fever.’ By this it appears that
the fever in question broke out as early as the beginning of March.
The disingenuousness of this author is particularly evident from
this quotation, if the period of the commencement of the disease be
correctly assigned: and that it is so is probable from the difficulty
of concealing the fact; as there must have been thousands of witnesses
to the progress of the fever. When therefore it was thought proper to
fix the odium of introducing the disease upon the Hankey (a project
of which Dr. Chisholm seems originally to have had no idea) it became
necessary for him to fix an earlier date to her arrival. Now, that the
Hankey did not arrive till towards the latter end of March, is verified
by the concurring testimony of Mr. and Mrs. Paiba, and of Mr. Bell, of
this city (New York) who happened to be in Grenada about that time,
and was personally acquainted with Mr. and Mrs. Paiba in that island.”

In answer to this Dr. Chisholm repeats his declaration that the Hankey
arrived at Grenada on the 18th of _February_, and not on the 19th
of March, as Dr. Smith (supposed on the authority of Mr. Paiba) had
stated. In proof of this he produces an incontestible evidence, viz.
an extract from the St. George’s Gazette in Grenada, of date 19th of
February, which begins thus: “By the ship Hankey of London, arrived
here _yesterday_ from the island of Boulam on the coast of Africa, we
are informed,” &c. The remainder of the extract contains an account of
the excessive mortality on board the ships; which, as it may perhaps be
exaggerated, it is needless to transcribe.

The next thing of consequence is the destruction of the bed-clothes
and effects of the deceased; of which Dr. Smith says, “Before the
Hankey put to sea, all the bedding of the sick was thrown overboard
or destroyed; the ship was washed from stem to stern, both above
and below, with salt water; and the purification was completed by
fumigating her with tar, pitch and gun-powder. In this clean condition
they bade farewel to Bulama on the 22d of November, 1792; but, in
attempting to pass through the channel near to the entrance into the
open sea, in a dark and foggy night, they got aground on a sand-bank,
upon the north side of the island of Formosa or Warang, belonging to
the Bijugas, who are represented as cannibals. The extreme terror
excited by this accident was not calculated to improve the health of
the people on board the Hankey; so that, when it became necessary to
take measures for their security and deliverance, only four men were
found in a condition to do duty, and all of these had intermittents.
With them, however, and his lady, Mr. Paiba set off, in an open boat,
for Bissao, to obtain assistance from the Portuguese settlement.
Thither he arrived, rowing through rains and fogs, in a leaky boat,
after being out two nights and a day; and having obtained such help
as he could, returned to the Hankey, got her off, and carried her to
Bissao. On the passage there _eight_ persons died who belonged to
this ship. At Bissao they refitted, and the Hankey _was a second time
purified as completely as she had been before leaving Bulama_.”

In answer to all this Dr. Chisholm _again declares_, “that the bedding
and effects of the deceased _were preserved_ on board the Hankey, and
constituted the seminium of the infection. Capt. William Liddle, of the
ship General Mathew, saw them on board; and it was in consequence of
that gentleman’s representation that the lieutenant governor, Mr. Home,
entered into a strict investigation of the matter; the general result
of which I have given; and the authenticity of it may be depended on.
Capt. Liddle is now resident in London, and Mr. Byles, the governor’s
secretary, is now resident commissary at Grenada; and these gentlemen
will readily testify to the truth of my statement. The destructive
articles I have mentioned _were not thrown overboard_ till the Hankey
arrived in Grenville Bay, when they were destroyed at the request of
Mr. Prendfoot, the gentleman who chartered the ship for England.”

Dr. Chisholm is likewise charged with having mis-stated the case of
a Capt. Remington, said to be the first who suffered by the fever in
Grenada. The words in Dr. Chisholm’s Essay are, “A Capt. Remington, an
intimate acquaintance of Capt. Coxe’s, was the first person who visited
the Hankey after her arrival in St. George’s bay. This person went on
board of her in the evening after she anchored, and remained three
days; at the end of which time he left St. George’s, and proceeded in
a drogher (a coasting vessel) to Grenville bay, where his ship, the
Adventure lay. He was seized with the malignant pestilential fever on
the passage; and the violence of the symptoms increased so rapidly, as,
on the third day, to put an end to his existence.” In opposition to
this Dr. Smith gives the following statement from Mr. Paiba: “He (Capt.
Remington) had been all day and all night coming from Grenville bay,
and had been wet through. He slept on board in his clothes; and went in
an open boat _the next day_ back to his ship: enough to kill any one
in that climate.” Dr. Chisholm replies “that the above statement is
not correct, nor founded on fact; Dr. Chisholm’s evidence for what he
said was founded on the information of captains of vessels, who knew
all the circumstances of his visit to the Hankey; and of Dr. Stewart,
an eminent practitioner, who attended him at Grenville bay, when he
landed there. Lastly, that the idea of his having returned to Grenville
bay in an open boat, is absurd; nothing of the kind having been ever
attempted.”

From this tedious account it is plain that the evidence relative to
the importation of the fever into Grenada by the Hankey is quite
contradictory, and subversive of itself, because we are unable to judge
between the two disputants. A further consideration of it would lead
us entirely from the subject of this treatise, into an endless dispute
about which of the two parties had spoken the truth. Setting aside
therefore _the whole_ of the evidence on both sides as insufficient, we
shall now proceed to give an account of the symptoms of the distemper
as described by Dr. Chisholm, and to which description there has never
been any objection made.

In the most violent kind of this fever, according to our author, “the
patient, without any previous complaint, suddenly becomes giddy;
he loses his eye-sight; every thing seems to move round him with
inconceivable velocity; he falls down almost insensible, and in that
state remains near half an hour, or upwards. During this paroxysm the
body feels cold, and is over-spread with cold sweat, which issues from
every pore in astonishing abundance. On his recovery the cold goes
off, and is instantly succeeded by intense heat, and quick, small,
hard pulse; the head achs dreadfully, particularly the fore part;
generally accompanied with pain in the right side and at the præcordia.
The last, however, has never been acute, and may rather be called
oppression than pain. The eyes are much inflamed, watery, protruded,
and wildly rolling; the face much flushed; much heat is felt at the
pit of the stomach, and that organ seems to be considerably affected
by the frequent retching and vomiting which then come on. The patient
soon after complains of intolerable pains in the small of his back and
in the calves of his legs; but the latter appears to be most violent.
During twelve, eighteen, twenty-four or thirty-six hours, these
symptoms continue increasing, except the quickness and hardness of the
pulse, which does not change materially during that time; and are then
succeeded by general coldness, cold sweat, a greater or less degree
of coma and delirium, or a state very much resembling intoxication.
Life in this state is lengthened out to sixty or ninety hours from
the first attack. A short interval of reason then takes place; the
patient considers himself better, and is, for a moment, flattered with
the prospect of recovery: but a fit as sudden and unexpected as the
first comes on, during which he foams at the mouth, rolls his eyes
dreadfully, and throws out and pulls back his extremities in quick
succession. In general the patient expires in this fit; but some have
recovered from it, and continued rational for a few hours longer, when
a second fit has carried them off.”

This, without much deviation, was the general progress of the worst
kind of the fever. In some, however, a comatose disposition showed
itself from the very first; in others the disease began with short
convulsive fits in frequent succession, followed by constant delirium
and cold clammy sweat, without any intervening heat. In a few cases the
first symptoms were coldness and shivering, as in other fevers.

The distinguishing symptoms were the uncommonly sudden attack, the
remarkably acute pain in the loins and calves of the legs, the watery,
inflamed and rolling eye, flushing of the face, tendency to coma, the
pain generally confined to the forehead, and the peculiar cast of the
delirium, during which the looks and actions of the patient very much
resembled those of a person intoxicated. It was never furious in any
other way than by making efforts to get out of bed; and these in a few
instances rose so high that the patients got up, dressed themselves,
and walked out a considerable way before they could be overpowered.
“The strength during the delirium is to appearance surprisingly great,
for it is frequently necessary to use the united efforts of two or
three men to keep the patient in bed. This is, however, no more than a
spasmodic affection of the muscles; for in reality the powers of the
sick in this disease are reduced to the extreme of debility, as is seen
in the convalescent state.”

The most unequivocal characteristic of this disease, however, according
to our author, is the appearance of a kind of petechiæ, but which look
rather like red or livid patches than what is commonly understood by
that word. They were _always_ the forerunners of death. In a few very
violent cases the body was almost of a livid or black colour, but they
were generally seated on the neck, shoulders and breast. _Vibices_
also, like those in the plague, described p. 258, sometimes made their
appearance, and were also a fatal presage.

Hæmorrhage occurred much more frequent and profuse in this than in any
other acute distemper our author had met with. “In several instances,
the immensity of blood discharged has evidently been the more immediate
cause of death. The robust, plethoric and gross habits have been the
most subject to it. It has taken place from the nostrils, mouth, anus,
and urethra; sometimes from the canthi (corners) of the eyes; but
never, I believe, from the ears or pores of the skin. The most profuse
discharge has been from the nostrils and anus, and has frequently,
amounted to three or four pounds at a time; the stools having been on
those occasions entirely composed of pure blood. Towards the close of
life, the blood thus discharged has appeared granulous, or like ichor,
with a sediment of a black gritty substance, and has been so extremely
offensive as to oblige all the attendants to keep at a considerable
distance till the hæmorrhage ceased. Hæmorrhage, however, has never
been critical, nor has it in any instance permanently relieved the
head-ach or pain in the breast or side.... Nearly about the period that
these profuse discharges came on, a rawness was felt on the whole of
the interior surface of the nose, and on several parts of it little
ulcers formed; on others, small eschars, which were remarkably itchy,
but on being touched, or an attempt made to detach them from the
membrane of the nose, were very painful, and bled. These disappeared
in proportion to the patient’s recovery; and I have reason to suspect,
that, when the issue of the disease was fatal, these little eschars
became gangrenous.”

In this distemper there was always a tendency to coma after the first
two days; and after the third, it certainly came on. On examining
the heads of two who died convulsed after having been comatose for
some time, a great quantity of serum was found in the brain; and, on
narrowly inspecting the eyes of those who were afterwards seized with
coma, the pupil was found manifestly dilated.

A remarkable symptom unnoticed in any other fever is taken notice of
by our author; viz. an affection of the testicles. “About the end of
the second day the patient began to complain of a violent pain in these
parts, accompanied with a contraction of the spermatic cord, and a
drawing up of the testicles towards the abdominal ring. On examination
they appear very much lessened in size, are drawn up considerably
towards the abdomen, and the scrotum appears at the same time
remarkably flaccid and empty. The surface of the scrotum becomes soon
after very painful, and an excoriation takes place, chiefly at the most
descending part, from which a considerable quantity of very offensive
purulent matter issues: at the same time a similar discharge from the
urethra takes place, which ceases with the disease when the event is
favourable, or becomes ichorous and bloody, and insufferably fœtid
when death is the consequence. In cases which terminate favourably,
the whole of the scrotum, in a few days, is covered with a crust of
hardened pus, which in the convalescent state, comes away very easily
by means of a warm bath. The thickness of this coat may be about the
fourth of a line; and, when separated, it much resembles moistened
parchment. In fatal cases, this affection of the scrotum always
terminates in gangrene a few hours before death.”

Another remarkable symptom is the change of voice to a shrill, soft
and low sound when compared with the natural tone, at the same time
that the syllables are more distinguished, and the words are strangely
lengthened out in a drawling and whining manner. This change of voice
affords a pretty certain prognostic; every alteration towards the
natural tone being an almost certain sign of a favourable change, and
the contrary if the voice becomes farther removed from it.

The pains felt in this fever were in a great measure peculiar to it,
and seem to have been of a spasmodic nature. In the head the pain shot
from the forehead, to which it was confined, invariably towards the
bottom of the orbits, where it was generally exquisite. Sometimes it
extended to the temples, where there was always a throbbing; but in
no case did it extend to the back part, or over the whole head. This
pain extended also to the balls of the eyes, which were protruded,
and seemed ready to start from their orbits, with an inflammation
externally, and a sensation of pain internally, rendering the admission
of light intolerable. In the legs the pain had its seat at the top of
the great tendon, immediately below the calf, and in the point where it
was seated a gnawing sensation was felt, occasioning exquisite torture,
with an involuntary contraction of the limb; so that, on the whole, our
author concludes that this pain much resembles the cramp, differing
only in being more permanent.

With regard to the pulse, our author observes, that in this disease “it
never intermits. Even at the approach of death it has not intermitted,
but has generally been remarkably tremulous, and so slow as to beat no
more than thirty times in a minute. On the whole, it has not been found
quicker than 130, or slower than 30, in a minute.” In violent cases the
pulse was hard, quick and small, but sometimes full; and when it was
so it was a good sign. It was however subject to excessive variations;
and it frequently happened, “especially in the robust, that, after the
first stage, flushing and chillness have often alternated in less than
a minute; and that, although the skin felt considerably warm, the pulse
has been no more than 52; but that, even when the low state came on,
in which there was always a disagreeable coldness of the surface, it
has been as quick, and nearly as full, as during the preceding febrile
stage, although unaccompanied with thirst, or any other evident symptom
of the existence of fever.”

In the state of delirium, Dr. Chisholm observes, that, whatever was
the subject of the patient’s raving thoughts, he was always strongly
under the impression of fear; and a word from the physician always
reduced him to implicit obedience, however restless he might have been
before. During this state he complained of no pain, even from blisters,
nor was he sensible of the operation of laxative medicines. On being
asked about his situation, he always answered that he was very well,
and sensible of no pain, as in the yellow fever already described. It
is observable, however, that the yellow colour, so remarkable in the
former, seldom took place in the Boulam fever; but indeed this symptom,
as has formerly been noticed, is by no means a characteristic either of
the one disease or the other; but Dr. Chisholm observes “that in some
protracted cases on shore, and in some among the sailors, which might
have been a combination of the pestilential and yellow fevers, this
symptom appeared about the 5th, 7th or 9th day.”

Besides the petechiæ and vibices, already mentioned, Dr. Chisholm takes
notice of two other sorts of eruptions, which appeared about the lips:
the one was such as frequently appears at the termination of the common
remittents, and was favourable; the other resembling spots made by the
fine black pencil of a painter, all round the mouth, but especially the
upper lip, and certainly affording a fatal prognostic.

This disease was attended with a suppression of urine, a violent pain
above the os pubis, a scalding in the urethra, a sense of fulness,
without any visible swelling, a contraction and distortion of the
penis; the urine generally of a deep red, sometimes brownish, green,
very often bloody, and in a few cases much inclining to black, and of
an oily consistence. Its smell was generally very offensive. All the
excretions were exceedingly offensive, but the fæces most remarkably
so towards the latter end of the disease; for in the beginning they
had no remarkable fœtor. The sick were almost universally costive,
which our author supposes to have arisen from a suspension of tone
in the intestinal canal; for by exciting action in the fibres a
large evacuation generally ensued. The colour of the fæces varied
from yellow, or a yellowish white, to black; and from a considerable
degree of thickness, to the exact appearance of coffee-grounds. The
matter discharged by vomit also varied from porraceous to black, and
resembling coffee badly boiled.

In this disease, as in the plague described by Thucydides, most other
diseases degenerated into it, or partook of its nature. Dysenteries
suddenly stopped, and were immediately succeeded by the symptoms
of pestilential fever. A remarkable instance of this is given in
twenty-seven recruits, who had been seized with dysentery, in
consequence of being exposed to rain, receiving the infection in the
hospital to which they were carried. The medicines exhibited with
a view to cure the dysentery seemed to be attended with surprising
effect; but in a short time symptoms of pestilential fever came
on, even in a few hours after those of dysentery had disappeared.
In like manner catarrhal complaints soon changed their nature.
Convalescents from other diseases, such as laboured under chronical
complaints, particularly rheumatism and inflammation of the liver, were
particularly subject to it. “The puerperal fever became malignant,
and of course fatal; and even among pregnant negro women, who might
otherwise have had it in the usual mild degree peculiar to that
description of people, many were reduced to a very dangerous situation
by it. In short, every disease in which the patient was liable to
infection, sooner or later assumed the appearance, and acquired the
danger, of the pestilential fever.”

This fever was said to be propagated from Grenada to others of the
West India islands, and to the United States, where in the same year,
1793, it raged with great violence in Philadelphia. Without entering
into any inquiry at present concerning the truth of this report, or
the origin of the fever itself, let us see whether from the symptoms
enumerated by Dr. Rush, who hath written a very lengthy dissertation
upon the disease, it was the same with the Boulam fever already
described. According to him the fever in 1793 was frequently preceded
by “costiveness, a dull pain in the right side, defect of appetite,
flatulence, perverted taste, heat in the stomach, giddiness or pain
in the head, a dull, watery, brilliant, yellow or red eye, dim and
imperfect vision, hoarseness, or slight sore throat, low spirits, or
unusual vivacity, a moisture on the hands, a disposition to sweat at
nights, or after moderate exercise, or a sudden suppression of night
sweats.... On entering a sick room the physician was first struck by
the _countenance_ of the patient. It was as much unlike that which is
exhibited in the common bilious fever, as the face of a wild animal
is unlike that of a domestic one. The eyes were sad, watery, and so
inflamed in some cases as to resemble two balls of fire. Sometimes they
had a most brilliant or ferocious appearance. The face was suffused
with blood, or of a dusky colour, and the whole countenance was dusky
and clouded. After the 10th of September, when the determination
of blood to the brain became universal, there was a preternatural
dilation of the pupil. Sighing attended in almost every case. The
skin was dry, and frequently of its natural temperature.... The pulse
at the beginning of the attack was sometimes full, tense and quick,
but frequently weak; sometimes so low that it could not be perceived
without pressing the wrists; and sometimes it had no preternatural
quickness. In many it intermitted after the fourth or fifth, and
sometimes after the fourteenth stroke. In some it was extremely slow;
even as low as thirty strokes in a minute. The pulse was also _tense_
and _chorded_. The slow intermitting pulse was observed more frequently
in children than adults, and supposed to proceed from a collection of
water in the brain. Impressed with this idea, I requested Mr. Coxe, one
of my pupils, to assist me in examining the state of the eye. For two
days we discovered no change in it; but on the third day after we began
to inspect the eyes, we both perceived a preternatural dilatation of
the pupils in different patients; and we seldom afterwards saw an eye
in which it was wanting. In Dr. Say it was attended with squinting, a
symptom which marks a high degree of a morbid affection of the brain.
Had this slowness or intermission of the pulse occurred only after
signs of inflammation or congestion had appeared in the brain, I should
have supposed that it had been derived wholly from that cause; but I
well recollect having felt it several days before I could discover
the least change in the pupil of the eye. I am forced therefore to
call in the operation of another cause, to assist in accounting for
this state of the pulse, and this I take to be a spasmodic affection,
accompanied with preternatural dilatation or contraction of the heart.
Lieutaud mentions this species of pulse in several places, as occurring
with an undue enlargement of this muscle. Dr. Ferriar describes a
case, in which a low, irregular, intermitting and hardly perceptible
pulse attended a morbid dilatation of the heart.... After the 10th of
September this undescribable or _sulky_ pulse became less observable,
and, in proportion as the weather cooled, it disappeared. It was
gradually succeeded by a pulse full, tense, quick, and as frequent
as in pleurisy or rheumatism. It differed, however, from a pleuritic
or rheumatic pulse, in imparting a very different sensation to the
fingers. No two strokes seemed to be exactly alike. Its action was of
a hobbling nature.... It was an alarming symptom.... The pulse most
frequently lessened in its fulness, and became gradually weak, frequent
and imperceptible before death; but I met with several cases in which
it was full, active, and even tense, in the last hours of life.

“Hæmorrhages occurred in the beginning of the disorder, chiefly from
the nose and uterus. Sometimes only a few drops of blood distilled
from the nose. As the disease advanced, the discharges of blood became
universal. They occurred from the gums, ears, stomach, bowels, and
urinary passages. Drops of blood issued from the inner canthus of the
left eye of Mr. Josiah Coates. Dr. Woodhouse attended a lady who bled
from the holes of her ears which had been made for ear-rings. Many
bled from the orifices which had been made in performing venesection,
several days after they appeared to have been healed; and some from
wounds in veins made in unsuccessful attempts to draw blood. These last
were very troublesome, and in some cases precipitated death....

“I was surprised to find so few marks of hepatic affection. I met with
but two cases in which the patient could lie only on the right side.
Many complained of a dull pain in the region of the liver, but very few
complained of that soreness to the touch, about the pit of the stomach,
which is taken notice of by authors, and which was universal in the
yellow fever of 1762. In proportion as the cool weather advanced, a
preternatural determination of the blood took place to the brain and
lungs. Many were affected with pneumonic symptoms, and some appeared
to die of sudden effusions of blood or serum in the lungs.... The
disease seldom appeared without nausea or vomiting. In some cases
they both occured for several days, or a week, before any fever took
place. This was more frequently the case where the disease _was taken
by exhalation from the putrid coffee, than by contagion_. The stomach
was so extremely irritable as to reject drinks of every kind. Sometimes
green or yellow bile was rejected on the first day of the disorder; but
I much oftener saw it continue for two days without discharging any
thing from the stomach, but the drinks which the patient had taken.
If the fever in any case came on without vomiting, or if it had been
checked by remedies that were ineffectual to remove it altogether, it
generally appeared or returned on the 4th or 5th day of the disorder.
I dreaded this symptom on those days; for, though it was not always
the forerunner of death, yet it generally rendered the recovery more
difficult and tedious. In some cases the vomiting was more or less
constant from the beginning to the end of the disorder, whether it
terminated in life or death. The vomiting which came on about the 4th
or 5th day was accompanied with a burning pain in the region of the
stomach. It produced great anxiety and tossing of the body from one
part of the bed to another. In some cases this painful burning occured
before any vomiting took place. Drinks were now rejected so suddenly
as often to be discharged over the hand that lifted them to the head
of the patient. The contents of the stomach were sometimes thrown up
with a convulsive motion which propelled them in a stream to a great
distance, and in some cases all over the clothes of the by-standers....
On the first and second days many puked from half a pint to nearly a
quart of yellow or green bile. In four (three of whom recovered) the
bile, even at this time, was black. On the 4th or 5th day a matter
resembling coffee-grounds was discharged.... Many recovered in whom
this symptom appeared. Towards the close of the disease there was
a discharge of a deep or pale-coloured black matter, with flakey
substances frequently swimming on the top of it.”

A quantity of grumous blood, dark coloured on the outside, was
frequently discharged by vomit towards the end of the disease; and,
along with all the discharges from the stomach, there was occasionally
a large worm, and frequently large quantities of mucus and tough
phlegm. Our author supposes the black blood and coffee-coloured matter
to be different from that which constitutes the true _black vomit_.
This last he supposes to arise in some cases from matter formed in
consequence of a mortification of the stomach.

The bowels were generally costive, sometimes with extreme pain,
tenesmus, and mucous and bloody discharges. Sometimes the disease came
on with diarrhœa, principally in those who had weak bowels. Sometimes
there was a tension of the abdomen, with pain in the lower part of
it. Flatulency, chiefly in the stomach, was almost universal in the
disorder throughout all its stages.

The colour and consistence of the fæces was various according to
the mode of treatment the patient had undergone. Where they were
spontaneous, or brought away only by gentle purgatives, their
appearance was natural; but when the patient was strongly purged,
they were dark-coloured, fœtid, and in large quantity. The colour was
sometimes green, sometimes olive. Their fœtor was proportioned to the
time they had been detained in the bowels. In one case, where tonics
had been used, and the patient had no stool for several days, a purge
produced such an excessively fœtid discharge, that the smell produced
fainting in an old woman who attended. Their acrimony was so great that
the rectum was excoriated, and an extensive inflammation sometimes
produced round its extremity. In some cases the stools were as white as
in the jaundice. Large round worms were frequently discharged with them.

The urine in this disease was sometimes plentiful and high-coloured,
sometimes clear, and sometimes turbid; sometimes discharged with a
burning pain, as in a gonorrhœa; sometimes it was suppressed; and in
one case the patient voided several quarts of limpid urine just before
he died.

Many were relieved on the first day by sweats, sometimes spontaneous,
and sometimes produced by diluting drinks, or strong purges; sometimes
of a yellow colour, and offensive smell. Sometimes they were cold,
though the pulse was full at the same time. In general, however,
the skin was dry, and there were but few instances of the disease
terminating by sweat after the third day. In some there was a great
discharge of mucus from the throat, occasioning an almost constant
hawking and spitting; and those always recovered.

In this fever, as in that of Boullam, and in the true plague, people
sometimes fell down suddenly in apoplexy, syncope or universal
convulsions. Some had numbness and immobility of their limbs. Some had
a coma (a continual sleepiness) or an obstinate wakefulness; the latter
chiefly attended a state of convalescence. In some the distemper began
with a violent cramp in the legs or arms. The last stage was attended
with a strong hiccup, which was a very dangerous symptom, as indeed it
is in all fevers. In some cases there was a deficiency of sensibility,
in others too much, so that the mere motion of the limbs was attended
with pain.

In this, as in the Boullam fever, the patient often manifested a
considerable degree of strength, even without any delirium. One of Dr.
Rush’s patients stood up before a looking-glass, and shaved himself,
the day on which he died. A delirium, however, was common, alternating
in some cases with the _exacerbations and remissions_ of the fever, but
in some continuing without intermission to a few hours before death.
Some had maniacal symptoms, without any appearance of fever; but in
many the understanding was not impaired throughout the whole course of
the disease.

In this disease the pains in almost every part of the body were very
distressing. In those cases, however, “where the system sunk under the
violent impression of the contagion, there was little or no pain.” In
other cases the patients were distressed with pains in their head,
particularly affecting the eyeballs. Sometimes it extended from the
back down the neck. A pain was felt in the ears, as if they were drawn
together by strings. The sides, stomach, liver and bowels were all
affected. A burning pain in the stomach was sometimes so excessive
that the patient shrieked out violently. The back was often the seat
of violent pain, which sometimes extended from the back to the thighs;
and the arms and legs were sometimes affected in such a manner that one
patient said his limbs felt as if scraped with a sharp instrument.

The thirst was generally moderate, but sometimes otherwise; and, when
excessive thirst came on in the last stage of the disorder, it was
a dangerous symptom. Water was preferred to all other drinks. The
appetite for food returned much sooner in this than in other fevers,
and was excessively keen. Coffee was relished in the remissions, in
every stage of the disorder. Wine was disliked, but malt-liquors
were agreeable. In some cases the recovery was attended with a great
propensity to venery, as in the true plague, but in an inferior degree.

In some cases the disease was attended with buboes and glandular
swellings. “I met with three cases (says our author) of swellings in
the inguinal, two in the parotid, and one in the cervical glands:
all these patients recovered without any suppuration of their
swellings. They were extremely painful in one case, in which no
redness or inflammation appeared. In the others there was considerable
inflammation, and but little pain.

“Several cases of carbuncles, such as occur in the plague, came under
my notice. They were large, hard swellings on the limbs, with a black
apex, which, upon being opened, discharged a thin, dark-coloured,
bloody matter. From one of these malignant sores an hæmorrhage took
place, which precipitated the death of an amiable lady. A large and
painful anthrax on the back succeeded a favourable issue of the fever
in another patient. I met with a woman who showed me the marks of a
number of small boils on her face and neck, which accompanied her
fever.... Notwithstanding the disposition to cutaneous eruptions in
this disorder, it was remarkable that blisters were much less disposed
to mortify than in the common nervous fever. Such was the insensibility
of the skin in some people, that blisters made no impression upon
it.... In every case of this disorder which came under my notice,
there were evident remissions or intermissions of the fever, or such
symptoms as were substituted for fever.”

The yellow colour rarely appeared before the third day, and generally
about the fifth or seventh day. The eyes were not always affected with
this colour. Sometimes it appeared first on the neck and breast; and
in one case it appeared behind the ears and on the crown of the head,
which had been bald for some years. It varied in the deepness of the
tint, and sometimes disappeared altogether; but, though some cases of
great malignity and danger appeared without any yellowness, it was
always a dangerous symptom when it appeared early. The cause of this
yellowness is by our author supposed to be an absorption and mixture of
the bile with the blood.

After death the body appeared of a deep yellow colour, sometimes a
few minutes after death; sometimes it was purple or black; and in one
case yellow above, and black below, the middle. In some it was pale,
as in common diseases, and many died with a placid countenance as in
natural sleep. In some the body grew cold soon after death, in others
not till six hours afterwards, and in like manner stiffness occurred
sometimes in one hour, in others not till six. Where evacuations had
been procured, symptoms of putrescence were longer in making their
appearance than in those who had used no medicines for that purpose.
Many discharged large quantities of black matter from the bowels,
others, of blood from the nose, mouth and bowels.

“The morbid appearances of the internal parts of the body (says the
Doctor) as they appear by dissection after death, from the yellow
fever, are different in different countries and in different years.”
Dr. Mitchill, in his history of the yellow fever in Virginia, in
1737 and 1741, informs us, that, in a female slave of forty, the
gall-bladder was outwardly of a deep yellow, but within, full of a
black, ropy, coagulated _atrabilis_ (black bile) obstructing the
biliary ducts. It was so thick, that it retained its figure when the
gall-bladder was opened. It more resembled bruised and mortified
blood than bile, though it would stain a knife or probe of a yellow
colour. Two thirds of the liver on its concave surface were of a deep
black colour, and round the gall-bladder it seemed to be mortified
and corrupted. A viscid bile, like that just described, was found in
the duodenum near the gall-bladder. The villous coat being taken off,
the other parts were found red and inflamed. The whole was lined with
a thick fur or slime. The omentum was so much wasted, that nothing
but its blood-vessels could be perceived. The stomach appeared to be
distended or swelled, lined like the duodenum, containing a quantity
of bile even blacker than that in the bladder. It was inflamed both on
the outside and inside. The lungs were inflated and all full of black
or livid spots; and on these spots were small blisters like those of an
erysipelas or gangrene, containing a yellow humour. The blood-vessels
in general were empty; only the vena portarum seemed full and distended
as usual. On cutting the sound part of the liver, the lungs or the
spleen, blood issued freely.

Dr. Mackittrick found the liver sphacelated, the gall-bladder full of
black bile, and the veins tinged with a black _fluid_ blood. In all
cases the stomach, duodenum and ilium were remarkably inflamed. The
pericardium contained a viscid yellow serum, and in larger quantity
than usual. The urinary bladder a little inflamed; the lungs sound.

Dr. Hume, of Jamaica, found the liver enlarged and turgid with bile,
and of a pale yellow colour; the stomach and duodenum sometimes
inflamed; and, in one case, the former had black spots of the size of a
crown-piece. He had seen some bodies in which there was no appearance
of inflammation of the stomach, though the patients had been afflicted
with excessive vomiting.

Dr. Lind’s account is given on p. 394.

Drs. Physic and Carthrall, of Philadelphia, found the brain in a
natural state; the viscera of the thorax perfectly sound; the blood in
the heart and veins fluid, similar in its consistence to the blood of
persons who have been hanged, or destroyed by electricity. “The stomach
and beginning of the duodenum are the parts that are most diseased.
In two persons, who died of the disease on the 5th day, the villous
membrane of the stomach, especially about its smaller end, was found
highly inflamed; and this inflammation extended through the pylorus
into the duodenum some way. The inflammation here was extremely similar
to that induced in the stomach by acrid poisons, as by arsenic, which
we have once had an opportunity of seeing in a person destroyed by it.
The bile was of its natural colour, but very viscid.”

In others the stomach was spotted with extravasated blood; and it
contained, as well as the intestines, a black liquor like that which
had been vomited and purged before death. The gentlemen were of opinion
that this must have been a secretion from the liver, as a fluid of the
same kind was found in the gall-bladder, of such an acrid nature that
it inflamed the operator’s hands, and the inflammation lasted some
days. The liver was of its natural appearance, or nearly so. These
dissections were made early in the season; and at that time Dr. Rush
is of opinion that the disease was not attended with any congestion in
the brain, though it was so afterwards; and accordingly we are informed
that Dr. Annan attended a dissection at Bush-hill, in which the vessels
of the brain were remarkably turgid. Dr. Rush, however, is likewise
of opinion, that the morbid appearances in the brain may cease after
death, as well as the suffusion of blood in the face disappears after
the retreat of the blood from the extremities of the vessels in the
last moments of life. “It is no new thing for morbid affections of the
brain to leave either slender or no marks of disease after death. Dr.
Quin has given a dissection of a child that died with all the symptoms
of hydrocephalus internus, and yet nothing was distinguished in the
brain but a slight turgescence of the blood-vessels. Dr. Girdlestone
says, that no injury appeared in the brains of those persons who died
of the symptomatic apoplexy which occurred in a spasmodic disease
which he describes in the East Indies; and Mr. Clark informs us that
the brain was in a natural state in every case of death from puerperal
fever, notwithstanding it seemed to be affected in many cases soon
after the attack of the disorder.”

With regard to the state of the blood in this distemper, Dr. Rush
says, that when drawn from a vein, it was, “1. In the greatest number
of cases, dense, and of a scarlet colour, without any separation
into crassamentum and serum. 2. In many cases it did separate into
crassamentum and yellow serum. 3. In a few cases the serum was of a
natural colour. 4. There were many cases in which the blood was as
sizy as in pneumony and rheumatism. 5. In some instances the blood was
covered with a blue pellicle of sizy lymph, while the part which lay in
the bottom of the bowl was dissolved. In two cases the lymph was mixed
with green streaks. 6. It was in a few instances of a dark colour, and
as fluid as _molasses_. Both this and the 5th kind of blood occurred
chiefly where bleeding had been omitted altogether, or used too
sparingly, in the beginning of the disorder. 7. In some patients the
blood in the course of the disease exhibited nearly all the appearances
which have been mentioned. They were varied by the time in which the
blood was drawn, and by the nature and force of the remedies which had
been used in the disorder.”

From this account of the different appearances of the blood, it appears
to have varied at the very first attack from an healthy state, and to
have gradually deviated from that state more and more, as the disease
advanced. Dr. Rush says,[150] from Dr. Mitchill’s History of the Yellow
Fever in Virginia, in 1741, that “blood drawn from a vein was always
dissolved. The same state of the blood was observed in many persons who
had been exposed to the contagion, who discovered no other symptom of
the disease.” In p. 70 Dr. Rush gives his own opinion in the following
words: “I shall say, hereafter, that the blood was seldom dissolved in
this fever;” and p. 73, speaking particularly of the blood, he enters
into an argumentation against the putrescency of that fluid. “It” (the
blood) says he, “has been supposed to undergo a change from a healthy
to a putrid state; and many of the symptoms which have been described,
particularly the hæmorrhages and eruptions on the skin, have been
ascribed to this supposed putrefaction of the blood. It would be easy
to multiply arguments to prove that no such thing as putrefaction can
take place in the blood; and that the symptoms which have been supposed
to prove its existence are all effects of a sudden, violent and rapid
inflammatory action, or pressure upon the blood-vessels; and hence
the external and internal hæmorrhages. The petechiæ on the surface of
the skin depend on the same cause. They are nothing but effusions of
serum or red blood, from a rupture or preternatural dilatation of the
capillary vessels. The smell emitted from persons affected with this
disease was far from being of a putrid nature; and, if this had been
the case, it would not have proved the existence of putrefaction in
the blood; for a putrid smell is often discharged from the lungs, and
from the pores in sweat, which is wholly unconnected with a putrid,
or perhaps any other morbid, state of the blood. There are plants
which discharge an odour which conveys to the nose a sensation like
that of putrefaction; and yet these plants exist at the same time in a
state of most healthy vegetation: nor does the early putrid smell of
a body which perishes with this fever prove a putrid change to have
taken place in the blood before death. All animals which die suddenly,
and without loss of blood, are disposed to a speedy putrefaction.
This has long been remarked in animals that have been killed after
a chace, or by lightning. The poisonous air called _samiel_, which
is described by Chardin, produces, when it destroys life, instant
putrefaction. The bodies of men who die of violent passions, or after
strong convulsions, or even after great muscular exertion, putrefy in
a few hours after death. The healthy state of the body depends upon
a certain state of arrangement in the fluids. A derangement of these
fluids is the natural consequence of the violent and rapid motions,
or of the undue pressure upon the solids, which have been mentioned.
It occurs in every case of death from indirect debility, whether it
be induced by the excessive stimulus of contagion, by the volatile
vitriolic acid which is supposed to constitute the destructive _samiel_
wind,[151] or by violent commotions excited in the body by external
or internal causes. The practice among fishermen in some countries of
breaking the heads of their fish as soon as they are taken out of the
water, in order to retard their putrefaction, proves the truth of the
explanation I have given of its cause soon after death. The sudden
extinction of life in the fish prevents those convulsive or violent
motions which induce sudden _disorganization_ in their bodies. It was
remarkable that putrefaction took place most speedily after death from
the yellow fever, where the commotions of the system were not relieved
by evacuations. In those cases where purges and bleeding had been used
it was much slower. There is a fact mentioned by Dr. Ferriar, from
Dr. Hamilton, late professor of anatomy at Glasgow, which may seem at
first to militate against the facts I have mentioned. He says that he
had observed that bodies which were brought into the dissecting room
that had petechiæ on them were longer in putrefying than any others.
The fevers of which the poor (the common subjects of dissection) die,
are generally of the low nervous kind. Great _direct_ debility is the
characteristic of those fevers. The petechiæ which occur in them appear
in the last stage of this direct debility. They are the effect, not of
too much impetus in the blood, as in the yellow fever, but of a defect
or total absence of it in the last hours of life. The slow progress of
the body to putrefaction after death, in the instances mentioned by
Dr. Hamilton, seems to depend upon the same cause as that to which I
have ascribed it in those cases of death from the yellow fever in which
evacuations had been used, viz. direct debility. In the former cases
this slowness of putrefaction is induced by nature, in the latter by
art. The effects of debility from both causes are, notwithstanding, the
same.”

  [150] Account of the Bilious Remitting Fever, &c. p. 106.

  [151] See p. 126, n. where an account is given of the samiel, and
  another hypothesis concerning its nature.

From this long detail, in which the author’s meaning seems rather
involved in obscurity, we may gather that in the fever of 1793 the
blood had no determinate appearance, but that, according to the action
of the vascular system, it was sizy or otherwise. This position, which
in my opinion is the meaning of the passage just now quoted, is not
supported by any facts. It is mentioned indeed that the blood in some
was sizy, in others quite fluid, but as the cases in which it was so
are not particularly related, we do not know whether the action of the
vessels was stronger in those where the blood was fluid than where it
was not. Certain it is, that the blood may be made fluid by certain
substances mixed with it, without any action of the vessels at all. The
poison of the ticunas, as well as all other animal poisons, renders the
blood fluid, yet this will kill instantaneously when injected into a
vein, before the vessels have time to act in such a manner as could be
supposed to change the texture of any of the fluids.[152] Or if this
still will not satisfy, we are assured that the poison of serpents, as
well as many other substances, which are not poisons, when mixed with
the blood taken out of the body, will prevent it from coagulating.
Granting, therefore, what hath not been proved, that the greater
the action of the vessels, the more fluid the blood will be, yet we
cannot know whether this fluidity be occasioned by the action of the
vessels, or the action of the vessels by the tendency to fluidity in
the blood. But it matters not which of the two is cause or effect: the
question is, Whether in the yellow fever does the ultimate effort of
the disease tend to produce any alteration in the texture of the blood
to fluidity, or otherwise? This can be known only from considering
the symptoms which take place in the last stage of the disorder, and
from dissections. Now, from the concurrent testimonies of all the
writers quoted in this treatise, it appears that towards the end of
the disease there is such a tendency to dissolution, that the whole
body seems ready to fall down into a putrid mass; or at least into
what is commonly called so, whether with strict propriety of language
or not, signifies little. In short, the difference between the plague
and yellow fever seems to be entirely of the same kind with that taken
notice of in this treatise, p. p. 269, 270, where the bile of a person
dying of a malignant fever was injected into the veins of a dog. Here
the blood was very fluid. In capt. Mawhood’s case (p. 385) the blood
flowed from his nose, eyes and gums, besides what he discharged by
vomit. Dr. Lining (p. 389) attests a similar tendency to dissolution in
the blood in a most remarkable manner. See also Dr. Lind’s opinion to
the same purpose, p. 393, Dr. Hillary’s, p. 395, Dr. Jackson’s account,
p. 399, Dr. Chisholm’s, p. 411; and lastly, Dr. Rush’s own testimony
concerning the hæmorrhages from all parts, lately quoted.

  [152] See p. 221–223.

As we have formerly seen, that in the plague there was no such tendency
to dissolution, but rather to coagulation, in the blood, it was thence
concluded that the immediate cause of the symptoms of plague is a
tendency in the blood to throw out the latent heat it contains, by
which means the parts on which these discharges fall, are burnt up to a
kind of cinder. In the yellow fever the reverse takes place. The blood
has a tendency to absorb heat, and if it does so it must of course
become thinner, for this is the nature of all fluids, and indeed it
is abundantly manifest that fluidity in all cases is an effect of the
absorption of heat.[153] In consequence of this absorption, the body
towards the latter end feels cold, the heat seems to retire from the
extremities towards the vital parts, and the vessels contracting and
losing their power by reason of the abstraction of sensible heat, the
pulse ceases entirely some time before death. Dr. Huxham takes notice
of this excessive coldness in the limbs taking place in a lady who
died of a malignant fever, and likewise that an intolerable stench
issued from her body for some time before her death, though kept clean
with all possible care. As the plague therefore is the highest of all
inflammatory diseases, so the yellow fever seems to be the highest of
the malignant class.

  [153] See p. 150.

It may be objected, however, that as hæmorrhages, petechiæ, black
vomiting, and convulsions, sometimes take place in the plague, we
cannot from the existence of similar symptoms in the yellow fever,
conclude that they are different diseases. But, with regard to the
first, it must be observed, that an hæmorrhage may ensue from a rupture
of vessels as well as from an oozing of blood in consequence of an
acrimonious thinness of blood. It is indeed to be questioned, except
in cases where blood is discharged by the pores of the skin, whether
any hæmorrhage takes place but by a rupture of vessels. In an healthy
subject, hæmorrhages very frequently take place from the nose where
the blood is of a very proper consistence; and Dr. Russel says that
he had occasion to see hæmorrhages from the nose and uterus only;
that in the advanced stages of the disease though the blood was paler
and of a _thinner_ consistence, the hæmorrhage was seldom profuse. It
was, however, of very bad omen; most of the cases in which it appeared
having terminated fatally.

That towards the end of this disease the blood should begin to absorb
the heat which it had before thrown out, is not wonderful. A tendency
to dissolution very probably does in all cases take place in a greater
or lesser degree; but we have not any reason to suppose that in the
true plague hæmorrhages ever are as frequent, violent, or attended with
such an apparent tendency to putrefaction, as in the yellow fever, and
consequently we must suppose that there is some _specific_ difference
between the state of the blood in the one disease and in the other.

Convulsions, though very frequent in the yellow fever, yet, according
to Dr. Russel, were very rare attendants on the access of the
pestilential fever. Even hiccup was seldom observed, and sneezing
not once. However, he says that convulsive motions of the limbs were
frequently observed in the course of the disease; but this is far
from what Dr. Chisholm says of the Boullam fever, where the patient
expired in a violent convulsive fit; or what Dr. Rush says of the
fever of 1793, in which the patient sometimes fell down in universal
convulsions. In short, the absence, or much less frequency, of nervous
symptoms in the plague, seems to constitute another _specific_
difference between the two.

With regard to black vomiting, it is neither peculiar to the plague
nor yellow fever. Dr. Miller[154] has shown that it may be occasioned
by almost any kind of acrid poison taken into the stomach. In proof of
this he quotes from Sauvages the case of a man who died in consequence
of taking a drachm of white arsenic instead of cream of tartar, in
whose stomach was found, on dissection, a black liquor which deposited
a sediment like powdered charcoal. The villous coat of the stomach
was likewise abraded. For other cases of the same kind he refers to
Wepfer de cicuta aquatica, Morgagni, &c. Another case of poison by
arsenic occurred in New-York hospital, in which the patient had a black
vomiting. In another case in which corrosive mercury was swallowed
by mistake, the patient, after being to appearance in a fair way of
recovery, began to vomit a dark-coloured matter, and died in a day or
two. The agaricus clypeatus, a kind of poisonous mushroom, brought
on bilious stools, locked jaw, vomiting, delirium, oppression of the
breast, sighing, anxiety, great prostration of strength, yellowness on
some parts of the skin, and death on the sixth day. On dissection the
stomach was found to be inflamed, the duodenum distended with flatus,
and the gall-bladder full of green and black bile.

  [154] Med. Repository, vol. ii, p. 412.

But the principal distinctions between the plague and yellow fever
seem to be the eruptive nature of the former, and the propensity in
the latter to attack strangers newly arrived from colder climates;
also in being more easily checked by cold than the plague. It has
already been remarked from Dr. Russel, that of _two thousand seven
hundred_ patients, whose cases he noted, every one had buboes. These,
however, were not all the cases he saw; for he mentions some that had
no eruptions; but from this it is impossible to avoid drawing the
conclusion, that eruptions are the true characteristics of the plague.
Of these two thousand seven hundred, eighteen hundred and forty-one had
buboes in one or both groins; five hundred and sixty-nine had them in
the arm-pit; two hundred and thirty-one had parotids; four hundred and
ninety, carbuncles; and seventy-four, spurious buboes. Now, in all the
number of cases of fever which Dr. Rush attended in 1793, he had only
two with buboes, and one parotid; and as to the carbuncles they do not
answer the description of those in the former part of this work.[155]
It is impossible therefore that any more clear line of distinction can
be drawn between the plague and yellow fever. The following table,
however, exhibiting at one view the symptoms of the plague, the yellow
fever, fever of Boullam, and fever of 1793, will perhaps set this
matter in a still clearer light.

  [155] See p. 257.

From a mere inspection of the detail of symptoms in this table, the
difference between the several distempers is obvious. It is evident
that none of them can with any kind of propriety be called higher and
lower degrees of the rest. The plague is _essentially_ different from
the other three, which seem indeed to be nearly allied; the Boullam
fever being only attended with more violent and malignant symptoms. We
ought now to enter into a particular inquiry concerning the origin and
nature of these fevers; but, as a knowledge of this is in some measure
dependent on the question, whether or not they are contagious, we shall
in the first place present the reader with the following extract from
a French treatise, in which the question seems to be handled in an
agreeable and judicious manner, and then make another attempt, by an
investigation of matter of fact, to determine whether the disease has
ever been excited by imported contagion or not:

“A very important question is--whether this disease is contagious.
The greater part of the American physicians are of opinion that it
is, and are persuaded that it is brought from the West Indies, by
the ships which arrive here in the beginning of every summer. It is
even from that opinion, and on their vigorous representations, that
quarantines have been established, which every vessel from the West
Indies is obliged to perform during 10 and sometimes 20 days at Fort
Mifflin, several miles distance from Philadelphia. This formality, so
troublesome to navigation, was observed this year (1798) with more
severity than ever it was; but without answering any good purpose for
the vessels; for very few ships’ companies appeared taken with the
_yellow_ or _putrid fever_. Nevertheless the epidemic, whatever name it
assumes, raged this year in Philadelphia with more fury than even in
1793. Besides, if the quarantine was a sure preservative, if almost all
the ships’ crews coming from the West Indies brought the _yellow fever_
with them, why should not CHARLESTON, NORFOLK, ALEXANDRIA, BALTIMORE,
BOSTON and SALEM, where no quarantines are performed, be affected with
the contagion, as well as New York and Philadelphia? The American
physicians are so convinced that the _yellow fever_ is contagious, that
they scrupulously prohibit persons in health from all communications
with those diseased; they order frequent _waterings_ in the streets and
about the houses where the fever has manifested itself, and aromatic
fumigations. They even order the clothes of those who have fallen by it
to be burned, as is practised with respect to those who die with the
plague. It must be confessed that their precautions, in this respect,
have in some sort been justified, on seeing all the individuals of one
family successively taken with it, and often at the same time, their
neighbours, and so on, to a number of people who might be authorised
to attribute their misfortunes only to their vicinage with the first
victims.


_Characters and most remarkable Symptoms_

OF THE

Plague, Yellow Fever, Fever of Boullam, and of Philadelphia in 1793.

(_In this table the mark Do. refers to the column immediately preceding._)


_General Characters._

                                       FEVER OF          FEVER OF
  PLAGUE.            YELLOW FEVER.     BOULLAM.          PHILADELPHIA
                                                         IN 1793.

  Known and          Not known to      Supposed by       Various opinions
  described          exist before the  Dr. Chisholm      concerning it.
  by ancient         last century.     to be a kind
  historians.                          of new disease
                                       originating in
                                       foul vessels on
                                       the coast of
                                       Africa in 1793.

  Attacks            Attacks           Do.               Attacks more
  indiscriminately   principally                         generally than
  people of all      those who change                    the common yellow
  nations.           their climates,                     fever.
                     especially from
                     cold to hot.

  Not brought on     Brought on        Do.               Do.
  by intemperance.   not only by
  At least Dr. P.    intemperance, but
  Russel never saw   by slight errors
  an instance.       in regimen.

  Sometimes seems    Attacks the       Attacks the       As in the yellow
  to spare the       robust much       intemperate and   fever.
  weakly and         more violently    robust.
  delicate, and to   than those of
  attack the robust. a contrary
                     description.

  People sometimes   Not observed.     Those attacked by Patient sometimes
  struck dead as                       the disease fall  falls down in
  by a stroke                          down giddy and    apoplexy, syncope
  of lightning.                        almost insensible or universal
  Sometimes fall                       with a profuse    convulsions.
  down suddenly,                       cold sweat.
  but revive,
  and by proper
  management regain
  their health in a
  short time.

  Death sometimes    Death sometimes   Do.               Do.
  takes place        within
  without any fever  twenty-four
  or complaint;      hours, but
  preceded only      not without
  by momentary       some previous
  sickness, by       complaints.
  eruptions of
  purple spots, or
  the breaking out
  of hard eschars
  in different
  parts of the body.

  Irregular          No remission,     Do.               Remissions and
  remissions and     but a cessation                     exacerbations.
  exacerbations.     of one set of
                     symptoms to make
                     way for another.

  Venereal appetite  Not observed.     Do.               Venereal appetite
  monstrously                                            increased but
  increased on                                           less than in the
  recovery.                                              plague.


_Symptoms of the Disease in various parts of the Body, or over the
whole System._

                                       FEVER OF          FEVER OF
  PLAGUE.            YELLOW FEVER.     BOULLAM.          PHILADELPHIA
                                                         IN 1793.

  Infection          Not commonly      Do.               Do.
  sometimes begins   observed.
  with apparent
  intoxication.

  Sometimes is felt  Not observed.     Infection felt at Do.
  like an electric                     the commencement
  stroke.                              of the disease,
                                       occasioning a
                                       nausea and rigor.

  Fainting very      Do.               Do.               Do.
  frequent.

  Convulsions rare   Not commonly      Convulsions       Tremors of the
  at the beginning.  observed.         sometimes very    limbs uncommon.
  Convulsive                           violent: the
  motions of                           patient often
  the limbs not                        expiring in a
  unfrequent                           fit.
  throughout the
  disease.

  Hiccup uncommon.   Hiccup extremely  Do.               Do.
                     common.

  Sudden loss of     Do.               Excessive         A surprising
  strength.                            strength during   degree of
                                       the delirium.     strength
                                                         sometimes only a
                                                         few hours before
                                                         death.

  Delirium at times. Do.               Do. Sometimes     Do.
                                       constant.

  Loss of speech,    Not observed.     Do.               Do.
  faltering and
  trembling of the
  tongue.

  Coma very general. Do.               Do.               Do.

  Muddiness of the   Grimness of       Eyes inflamed,    Eyes watery,
  eyes, scarce to    countenance. Eyes watery, rolling   inflamed, or like
  be described.      red and heavy.    and protruded.    balls of fire.
                                                         Countenance wild
                                                         and ferocious.

  A solitary         A deep yellow     The yellow colour Yellow colour
  instance of the    colour all over   scarcely metvery  frequent.
  patient becoming   the body so        with.
  green all over.    common that the
                     disease has one
                     of its names from
                     it.

  Eruptions of       Never observed.   A kind of small   The carbuncles 
  the nature                           eschars in the    do not answer to
  of eschars,                          nose. Small       any description
  sometimes                            black spots on    of those in the
  small, and                           the upper lip,    plague.
  called tokens,                       but neither
  pepper-corns, &c.                    resembling
  sometimes larger,                    the tokens or
  and called                           carbuncles in
  carbuncles, on                       the plague.
  many different                       Carbuncles
  parts of the body.                   mentioned, but
                                       not described.

  Buboes in the      Very rarely       Sometimes         A very few
  inguinal,          observed.         observed, but
     instances.
  axillary and                         only in fatal
  parotid glands                       cases.
  exceedingly
  common.

  Pulse extremely    Pulse sometimes   Pulse             Pulse disappeared
  variable;          indistinguishable disappearing on   as in the plague
  disappearing       from that of a    pressure. Did not and Boullam
  entirely on        healthy person,   intermit even at  fever; otherwise
  pressure; often    even a short time the approach of   as in the yellow
  intermitting.      before death.     death.            fever.
                     Otherwise of
                     all possible
                     varieties.
                     Sometimes
                     entirely gone a
                     considerable time
                     before death.

  Excessive          Not observed.     Do.               Do.
  uneasiness at the  In the last
  heart. One person  stage the heart
  died with violent  palpitates
  palpitation.       strongly.

  Violent pain at    Universal in the  Very frequently   Disease sometimes
  the pit of the     yellow fever of   observed.         began with a pain
  stomach, which     1762.                               in the stomach.
  could not bear                                         A burning pain
  the touch.                                             frequently
                                                         accompanied the
                                                         vomiting.

  Hæmorrhages not    Hæmorrhages       Do.               Do.
  very common, and   excessively
  only from the      common from every
  nose and uterus.   part of the body.

  Vomiting of        Vomiting of       Do.               Do.
  yellow, green and  matters of the
  black matter.      same kind;
                     also of matter
                     resembling coffee
                     grounds with
                     flaky substances
                     floating in it.

  Stools less        Stools            Do. Immense       Stools extremely
  fœtid than in a    excessively       quantities of     fœtid when
  common tertian.    fœtid, and in     excessively fœtid strong evacuants
  Dark coloured      great quantity.   blood discharged. had been used,
  blood sometimes                                        otherwise the
  discharged.                                            fœtor was less.

  Sweats of various  Not observed.     Not observed.     Yellow and fœtid
  colours, and                                           sweats.
  fœtid.

  Sweat the natural  No natural        Do.               Seldom terminated
  crisis of the      crisis.                             by sweat after
  distemper.                                             the third day.


_Appearances on Dissection._

                                       FEVER OF          FEVER OF
  PLAGUE.            YELLOW FEVER.     BOULLAM.          PHILADELPHIA
                                                         IN 1793.

  Bile of a black    Bile of a black   Intestines        Bile very viscid.
  and greenish       colour, and very  mortified.
  colour; turning    viscid.                             Congestion of
  quite black by                       Effusions of      blood in the
  the addition       Stomach affected  blood and serum   brain.
  of spirit of       by gangrenous     in the brain.
  nitre; a lasting   spots called                        Blood in a fluid
  grass green by     carbuncles by Dr. Liver sometimes   state. Stomach
  adding spirit      Lining.           shrunk up into    and intestines
  of vitriol; and                      half its natural  inflamed.
  of a yellow by     Blood very fluid, size.
  the addition of    and the vessels                     Liver sometimes
  alkalies.          of the viscera                      of its natural
                     much distended.                     appearance.
  Heart of an
  extraordinary      Duodenum and
  bigness; in seven  other parts of
  cases stuffed      the intestines
  with thick, black  mortified.
  blood; in one,
  filled with a      Worms from
  large polypus;     putrefaction
  in another the     found in the
  contents not       stomach in six
  mentioned.         hours.

  Lungs in five      Omentum and its
  cases either       appendages of a
  purple, livid,     dark grey colour,
  or covered with    and uncommonly
  spots of these     dry.
  colours.
                     Liver and spleen
  Liver greatly      enlarged.
  enlarged, with
  mortified spots
  in five cases.
  Stuffed also with
  thick blood.

  Mortifications
  in the brain,
  intestines, &c.

  Abscesses in
  two cases; one
  in the muscular
  integuments of
  the thorax, the
  other in the
  aorta.


Fever of 1798.

_Doctors_ RAND _and_ WARREN’s _Dissections_.

  CASE I. Patient died   CASE II. Death on the  CASE III. Death on
  on the 6th day. Lungs  12th day. Patient      the fourth day. Lungs
  filled with dark       had been delirious     inflamed on the fore
  blood. Air vessels     since the 6th. Blood   part, and exceedingly
  not distended. Large   vessels of the brain   stuffed with blood
  extravasation of       greatly distended.     in the back parts.
  firmly coagulated      An effusion of serum   Liver inflamed, and
  blood in the thorax.   between the dura       of a very dense
  Fluid blood in the     and pia mater. A       consistence. Gall
  pericardium. Coronary  band of coagulated     bladder entirely
  veins extremely        lymph producing an     obliterated; its coats
  distended. Liver       adhesion between the   forming a confused
  inflamed on both       two coverings of the   membranous substance
  sides, and indurated   brain, under the       by coalescence with
  as if boiled. Gall     sagittal suture. Lungs the neighbouring
  bladder contracted,    adhered firmly to      parts. Stomach covered
  and containing only    the pleura, and had    in the inside with the
  about a quarter of an  several indurations    black vomit. Colon and
  ounce of a substance   of the size of a       part of the omentum
  resembling pitch.      pigeon’s egg. Left     inflamed.
  The secretion of       lobe extremely
  bile had apparently    diseased, and in a        *   *   *   *
  ceased for some time.  state of suppuration.
  Stomach and intestines Liver much enlarged    In the two cases where
  inflamed, and their    and inflamed, the      the gall bladder had
  veins distended.       inside of the great    been diseased, and
  Omentum thickened      lobe near the gall     the liver did not
  and dark coloured      bladder appearing as   perform its functions,
  from the swelling of   if contused. Stomach   the patients became
  its vessels. Spleen    covered on the inside  yellow; but not in the
  enlarged but without   with the matter of     other, where the bile
  inflammation.          the black vomit,       was in due quantity.
                         though the patient     In the second case the
                         had no evacuation of   patient had previously
                         that kind. Duodenum    had a pulmonary
                         and small intestines   complaint.
                         much inflamed. Gall
                         bladder full of bile,
                         and ducts pervious.
                         Bladder contracted to
                         the size of a pullet’s
                         egg, with a quantity
                         of blood effused in
                         it.

“Nevertheless, if this distemper was as contagious as certain
physicians pretend, why should they not be the first to be taken with
it; they who see, examine and touch many patients every day? Why should
not those who nurse them day and night, who continually breathe those
putrid miasmata; why should not those who attend the hospitals, those
who daily carry 30 or 40 coffins to the grave, be taken with it? We do
not hear, however, that the physicians, surgeons, nurses and sextons
have enlarged the funeral list more than any other class of citizens.
Some doubtless have fallen, and perhaps they owed their death to their
frequent communications with the sick; but would the epidemic have
spared them in any other condition, more than a number of unfortunate
people who are neither physicians nor nurses?

“Another particular not less remarkable is, that the _yellow fever_
seems hitherto to have spared the Frenchmen who have resided in the
West India colonies, the greatest part of whom have nevertheless
staid in New York and Philadelphia during the _yellow fever_, and
have lived in the midst of the contagious air which proves so fatal
to the Americans. The result of all this is, that, notwithstanding
four years’ experience, notwithstanding the public and private
researches and discussions which took place between the physicians and
philosophers of the American continent, there is still much uncertainty
on the nature of the distemper which so rapidly depopulates New York
and Philadelphia. Every opinion, every system, presents palpable
contradictions, and is liable to objections which it is difficult, not
to say impossible, to answer in a satisfactory manner. If the disease
be contagious, why are not the physicians, the nurses, the servants
of the hospitals, taken sooner than persons who have no sort of
communication with the sick?

“If it be not contagious, how happens it that the natives of every age
and sex, many of which, the women and children especially, live in a
pretty sober manner, and seldom drink any of those liquors so liable to
inflame the blood, are taken with it, and fall, in spite of all the
efforts of medicine? How happens it that the Europeans and Frenchmen
who have never been in the colonies are attacked like the Americans,
whilst the planters in the West Indies are spared?

“On the other hand, if, as the French physicians pretend, this is
nothing else than the malignant putrid fever, often prevalent in
Hispaniola, how happens it that those medicines and that mode of
treatment which were so frequently successful in the colonies have
no sort of success when administered to Americans, and seldom with
Europeans? Why is this fever attended, in its very first stage, with
vomitings of blood, bile, black spots, _purples_ and other alarming
symptoms, which they frequently have at Hispaniola? How comes it that
the West India planters, who, while they resided in the colonies,
had frequent attacks of putrid and often inflammatory fevers,
enjoy the most blooming health ever since they have been on the
American continent? And why are they not taken with those putrid and
inflammatory fevers, at a time when those who have given them an asylum
are the daily victims of it? Finally, if we must attribute the epidemic
to no other cause than the immoderate heat of the summer, which is
really greater here for two or three months than at Hispaniola, where
a land and sea breeze tempers its violence, why does it not stop its
ravages when the heat moderates? We have observed in the epidemics
of New York and Philadelphia, that they were less destructive in the
burning dog-days than in the months of September and October, when the
mornings, evenings and nights begin to be cool, and even cold enough to
allow people to go clothed as warmly as in winter.

“We have now a recent and striking example that it is not heat only
which causes the epidemics; since there were only, in the month of
September, three or four days of great heat. The rest were very cool.
It may even be said that from the 22d it was cold, especially on the
28th and 29th, when a violent north wind obliged many people to have a
fire. The number of deaths never were, however, so numerous as they
have been since the 20th of September. The funeral list, which in July
and August amounted to 40 per day, reached on the 20th of September to
78, the 22d, 68, the 23d, 71, the 24th, 63, the 25th, 80, the 26th, 77,
the 27th, 96, the 28th, 106, the 29th, 76, and from the 29th at twelve
o’clock, to the 1st of October, same hour, the number was 170; a number
as prodigious as it is frightful: we could not therefore even flatter
ourselves that the severest frosts of the end of October would dispel
the epidemic, did not experience afford us that comforting hope.

“What then is the physical cause of this scourge, which all human
prudence and science are unable to avert? The ministers of religion
will not fail to ascribe it to celestial wrath, and to advise prayers,
fast and charity to appease it. Those pious practices cannot assuredly
do harm; but the philosophical observer, who does not conceive that
Philadelphia and New York should have excited the Heavenly wrath more
than those of other cities of the continent, will seek for more natural
causes, and will examine whether they should not be attributed to some
local and peculiar vice of those two unfortunate cities, and perhaps
to the temperament, the diet, the mode of life, of their inhabitants.
Respecting this, we do not find, in the _localities_ of New York and
Philadelphia sufficient reasons, nor in the constitutions or mode of
life of their inhabitants sufficient variations, to mark them as the
victims of the _yellow fever_, while the inhabitants [of other places]
are free from it.

“I am however inclined to think that New York and Philadelphia, more
than any other cities, contain causes of corruption or putridity,
occasioned by their size and the extent of their commerce, which, added
to the high mode of life of the Americans, may be the source of the
calamity which now affects them.

“In effect, we observe that in these two cities the epidemic has
constantly manifested itself in those parts which are not only the most
commercial, but also where the _common_ sinks of the city meet; where
the houses, inhabited by the poorer class of people, being smaller,
and more crowded together; where the stores contain most provisions
liable to fermentation and putridity; where the shipping crowded in the
_wharfs_ render the water stagnant; where immense quantities of dirt
and litter are brought from every quarter for the purpose of filling
up new wharves and other places designed to be taken from the sea, to
enlarge lands to build upon; finally, where the water used to drink
does not reach the pumps of the lower part of the city until it has
filtrated through the burying-grounds and privy-houses of the upper
parts, most of which have no walls, and are never emptied.

“Let us add to all those causes of infection the dead dogs, cats, pigs,
and rats, which are thrown into the common sinks and docks, the rotten
fish, and the privies, which in several houses, especially at New York,
are nothing but _tubs_, which are emptied weekly on the sea shore, and
we shall have less reason to wonder at the putrid exhalations which
issue on the eastern part of New York, and at Philadelphia on that part
contiguous to the Delaware, and which are capable of infecting the
whole atmosphere, and to impair the health of those who live in it. If
the people who dwell in those parts are not scrupulously sober, if they
frequently indulge in the use of spiritous liquors, if they feed on
such food as is generally known to be unhealthy, is it to be wondered
that, with such a mode of life, their blood should be more disposed to
inflammation and to be dissolved and corrupted, in the midst of an air
already corrupted and loaded with destructive miasmata?

“Now every man knows that those who live contiguous to the river at New
York, and the Delaware at Philadelphia, mostly sailors, shipwrights,
truckmen, labourers, tavernkeepers, &c. seldom trouble themselves about
the quantity of their foods and drinks, but indulge copiously in the
use of strong liquors, of which an astonishing consumption is made
in those parts. They are not in other respects more careful as to
cleanliness in their narrow and low houses. There, in a _hole_ called
a _bedroom_, and on a feather-bed half rotted, in a heap of rags half
devoured by insects still more disgusting, two and sometimes three
individuals, covered with sweat, often drunk, sleep, and still increase
the filth by their shameful and dirty mode of life. Shall we find it
strange that those infected haunts should shed forth in the morning
a mephitic air, capable of suffocating the most robust and vigorous
men? Shall we wonder that those who breathe this pestilential gaz are
suddenly seized with a fever? in itself perhaps not very dangerous,
if it were treated in a suitable manner. But what is their method of
treating it? They do not even know the name of _ptisan_, still less the
use of _anodynes_, nor that of _salt of nitre_, nor of _camphor_, so
proper to prevent putridity. Punch, made with rum; water mixed with gin
and molasses; a sort of soup made with Madeira wine; fish; raw oysters,
&c. these are their first medicines. If their wives or friends go to
consult the apothecary, he advises the _castor-oil_, or the famous
calomel pills or powders, whose virtues the quacks extol for every
disease. Finally, if the fever increases, the doctor is called, who
administers a light puke of 12 or 15 grains of tartar emetic, a plenty
of laudanum to procure sleep, and who, seeing the case desperate,
withdraws, saying that he was called too late![156]

  [156] In Dr. Rush’s account of the fever of 1793, we find the
  following remarks on the French mode of practice to which it seems
  remarkable that our author has given no answer: “I proceed with
  reluctance to inquire into the comparative success of the French
  practice. It would not be difficult to decide upon it from many
  facts that came under my notice in the city; but I shall rest its
  merit wholly upon the returns of the number of deaths at Bush-hill.
  This hospital, after the 22d of September, was put under the care
  of a French physician, who was assisted by one of the physicians of
  the city. The hospital was in a pleasant and airy situation; it was
  provided with all the necessaries and comforts for sick people that
  humanity could invent, or liberality supply. The attendants were
  devoted to their duty, and cleanliness and order pervaded every room
  in the house. The reputation of this hospital, and of the French
  physician, drew patients to it in the early stage of the disorder.
  Of this I have been assured in a letter from Dr. Annan, who was
  appointed to examine and give orders of admission into the hospital
  to such of the poor of the district of Southwark, as could not be
  taken care of in their own houses. Mr. Olden has likewise informed
  me, that most of the patients who were sent to the hospital by the
  city committee (of which he was a member) were in the first stage
  of the fever. With all these advantages, the deaths between the 22d
  of September and the 6th of November, amounted to 448 out of 807
  patients who were admitted into the hospital within that time. Three
  fourths of all the blacks (nearly 20) who were patients in this
  hospital died. A list of the medicines prescribed there may be seen
  in the minutes of the proceedings of the city committee. Calomel and
  jalap are not among them. Moderate bleeding and purging with glauber
  salts, I have been informed were used in some cases by the physicians
  of this hospital. The proportion of deaths to the recoveries, as it
  appears in the minutes of the committee from whence the report is
  taken, is truly melancholy!”

“Although the inhabitants of the other parts of the city who are in
better circumstances follow a mode of life more regular, feed on more
wholesome aliment, and are much more cleanly in their houses (except
however _feather-beds_ and _lower bedrooms_) it is nevertheless a
fact that they are much inclined, the men especially, to eat salt
meat, meat half cooked, green fruit, and still more to drink spiritous
wines. Several of them allow themselves an immoderate use of the latter
between dinner and tea-time, the strength of which, added to that of
the high-spiced food, and liquors, must necessarily increase in their
blood that fermentation already excited by the heat of the season. Now,
shall we not concede that bodies thus predisposed ought to be more
susceptible than others of the impression of the corrupted _miasmata_
which are constantly exhaled from every thing that surrounds them; from
the common sewers, the wharves or the docks; from the dirt and litter
of the alleys and lanes; from the sulphureous bilge-water of ships;
from the cellars and from the stores; in short, from those houses which
contain sick, dying and dead persons?”

Here the author, after stating objections on both sides, seems at last
to determine that the disease is produced by putrid effluvia. The
dispute on this subject, however, hath continued so long, that we can
by no means expect to settle it in this treatise. At first view one
would think that nothing could be more easy than to determine whether
the disease arose soon after the arrival of foreign vessels, or in
places which had no connexion with maritime affairs. But when we come
to particulars there is such a strange disagreement and contradiction
concerning facts, that we are in every instance driven back into the
wide field of theory and argumentation. One instance of this we have
already had in the case of the Boullam fever said to be imported by
the _Hankey_. Let us now try another. Dr. Currie of Philadelphia, in a
letter to Mr. Wynkoop of date October 10th, 1797, says that the fever
at New-York, of 1795, was proved “by unquestionable facts,” to have
been introduced from Port au Prince by the brig Zephyr; and for a proof
of this he refers to a letter of the health committee of New York to
the governor, dated September 8th of that year. From this letter it
appears that Dr. Treat visited this vessel on the 28th of July, where
he found three men ill of what he called a bilious _remitting fever_,
and the body of one who died that morning. Two days after, the Doctor
was taken ill, and died in eight days, with unequivocal symptoms of
yellow fever. On the 25th, four persons from on board the ship William,
from Liverpool, which arrived several weeks before (the crew of which
till this time had been healthy) were taken ill of fever, and died with
similar symptoms in seven days. Nothing can be more direct than this
evidence, yet it did not give satisfaction.

The fact was impugned by the late Dr. E. Smith, in a letter to Dr.
Buel,[157] who produces such evidence as, in his opinion, “establishes
it beyond a contradiction, that neither Dr. Treat nor any other person
contracted a fever, such as prevailed in New York in 1795, from any
sick or dead man, or any thing else connected with the vessel in
question.”

  [157] Webster’s Collection, p. 98.

The evidence brought forward is the declaration and deposition of capt.
Bird. In a letter to Dr. Dingley, the captain “thinks it his duty to
contradict the report” that Dr. Treat “caught the disease of which he
died on board the Zephyr.” He contradicts it by a deposition, that “the
mate and one mariner had the _fever and ague_ seventeen days on shore,
and came on board with the same disease; and the captain himself had a
dysentery on his arrival in New York; and John Wheeler, aged 16 years,
died on the day of the arrival of the brig in New York, by _worms
crawling up into his throat, and choking him_. He was sewed up in a
piece of canvass, and ready to be committed to the deep, when Dr. Treat
came on board, who desired the captain to have the canvass opened, that
he might inspect the body; and he only cut the canvass over the face,
but did not make any other examination of the body.”

How far this proves captain Bird’s assertion, that Dr. Treat _did not_
catch the disease on board the Zephyr, the reader will judge. It is,
however, inconsistent with the plan of this treatise to enter into
an examination of contradictory evidence concerning matters of fact.
Accounting as _nothing_, therefore, all that has been said, _by either
party_, concerning the brig Zephyr, let us proceed to other testimonies.

In a collection of _facts_ and _observations_ by the College of
Physicians, published last year, we find the following remarkable
accounts tending to prove that the disease was introduced by the ship
Deborah, from Port au Prince and Jeremie in St. Domingo: 1. In a letter
from Dr. Stevens to Dr. Griffiths it is stated, that “the yellow
fever prevailed in almost all the sea-port towns in the French part
of Hispaniola, particularly at Cape Nichola Mole, where it raged so
violently that it obliged the British to abandon the post sooner than
they intended. About the same time it appeared in the harbour of St.
Thomas, and was so destructive to foreigners, that it obtained the name
of _the plague_.” The Doctor saw several cases of it in St. Domingo,
during the months of August and September, 1798, and “these were
entirely confined to _American seamen_, while the native inhabitants of
the city were totally exempt from it.” 2. From this very sickly coast
arrived the Deborah on the eighth of July. 3. On the 12th of August
John Lewis, mate of the Deborah, informed Dr. Currie, that the vessel
had lost _seven_ persons with fever on board during her passage, and
one by accident; _and that she had been employed as a transport in the
British service_ previous _to her taking in her cargo at Jeremie._
4. Mr. Thomas Town informed Dr. Wistar, that, on the first of August,
1798, he was told by Alexander Philips, of Water-street, that he (Mr.
Philips) had brought up two or three sick people from the Deborah, in
one or two boats. Some of them he had brought to his own house; and one
was dead. Philips himself was sick at the same time, and died a day
or two after. 5. Mr. Purdon informed Dr. Currie that he had a similar
account from Mr. Philips, whom he saw on the first or second of August
in apparent good health, and that he died on the Saturday following.

All this, and further evidence seemingly equally strong, was set aside
with the greatest facility by bringing counter-evidence, particularly
that of Mrs. Philips, who denied that there were any sick people in
the house; and by bringing instances of the fever existing in town
before the vessel arrived. It is needless therefore to trouble the
reader with any further discussion of this evidence more than the rest.
As the ancient Britons, in their letter to Aetius, lamented that the
_barbarians_ drove them to the sea, and the _sea_ drove them back to
the barbarians, so may we lament, in the present investigation, that
the uncertainty of theory drives us to _facts_, and the uncertainty
of supposed facts drives us to _theory_. Still, however, we shall not
despair. The introduction of a disease into a large city is much more
difficult to be traced than in a smaller one. In the year 1794 the
disease appeared in the town of New Haven in Connecticut. Dr. Monson of
that place informs us, that it appeared on the 10th of June, when Mrs.
Gorham, residing on the _Long wharf_, was visited by Dr. Hotchkiss, who
found her affected with symptoms of the yellow fever. In three days
her complaints suddenly vanished, and she was supposed to be in a fair
way of recovery, but the same evening she vomited matter resembling
coffee-grounds, and died next day. On the same day that Mrs. Gorham
died, Dr. Monson visited her niece, a girl of eight years of age, who
had staid a week with her aunt, and was taken ill three days before.
The day after the Doctor saw her she was suddenly relieved as her aunt
had been, but in a few hours vomited matter like coffee-grounds, and
died next day. These and some other similar cases having alarmed the
select men, inquiry was made, when “it appeared, that, in the beginning
of June, capt. Truman arrived from Martinico, in a sloop that was
infected with the contagion of the yellow fever; that this vessel lay
at the _wharf_, within a few rods of Mrs. Gorham’s residence; that she
had on board a chest of clothes which had belonged to a mariner who
died of the yellow fever in Martinico; and that his chest was carried
into Mr. Austin’s store, and opened in presence of Capt. Truman, Mr.
Austin, Henry Hubbard, and Polly Gorham: the three last died in a short
time after their exposure to the contents of the chest. Hence it is
highly probable that Mrs. Gorham caught the disease from the infected
sloop or clothing. Mr. Austin’s store stands within three or four rods
of Mr. Gorham’s house; and no person in town was known to have the
yellow fever previous to capt. Truman’s arrival.”

In his further account of this fever Dr. Monson shows that it was
contagious in the highest degree, and that Mr. Gorham’s house proved a
kind of seminary from whence the disease spread itself. “June 26 (says
he) Isaac Gorham lost an infant child with the yellow fever; and soon
after his son and daughter were affected with it: the former died.
Solomon Mudge died on the 30th; Jacob Thomson’s negro woman on the 1st
of July; Archibald McNeil on the 9th; Polly Brown on the 3d of August;
John Storer, jun. and John Hide, on the 8th; and widow Thomson on the
10th. Jacob Thomson’s negro woman, Solomon Mudge, John Storer, jun.
and John Hide, had visited Mr. Gorham’s house a few days before their
illness; Polly Brown and Mrs. Thomson nursed in Mr. Gorham’s family;
and Archibald McNeil nursed Solomon Mudge. Elias Gill died on the 12th
of August, and Samuel Griswold’s wife on the 7th: the former visited
Mr. Gorham’s house, the latter nursed in his family.

“There were a number of persons who caught the disease at Mr. Gorham’s
house, and recovered.

“Mrs. Thomson, on the first day of her illness, was moved half a
mile from Mr. Gorham’s, into George-street. Luther Fitch caught the
disease from Mrs. Thomson, and communicated it to his servant maid.
Both recovered. Mr. Fitch lives in College-street, nearly three
quarters of a mile distant from Mr. Gorham’s house. I could trace the
disease throughout the town. No person had the yellow fever unless
in consequence of attending the sick, or of being exposed by nurses,
infected houses, clothing, or furniture.

“I have inquired of several aged persons in this town relative to the
yellow fever, whether they knew of its having ever been here previous
to June 1794, and there is but a single instance; the facts relating to
which are these: In the year 1743 a transient person, by the name of
Nevins, who came from the West Indies, lodged at the house of Nathaniel
Brown, an inn-keeper in this city. The man was taken very sick in the
night, and died shortly afterwards; and his body was very yellow after
death. Mr. Brown’s wife sickened in a short time, and died of the same
complaint, which was at that time supposed to be the yellow fever.

“I am credibly informed that several persons at Mill-river, in
Fairfield county, and also at New London, died with the yellow fever in
August and September, 1795. It was propagated there by infected persons
from New York.

“Capt. John Smith died in this town, the 20th of August, 1795. He
caught the disease in New York, and communicated it to one of his negro
servants.”

On the whole, Dr. Monson concludes, “that the yellow fever is seldom
or never generated in this country, and that it is always imported
from abroad. An objection to the idea of its being generated in this
country is, that it was never known in the interior of this state, or
of the United States, so far as I can learn. Had it ever appeared in
Connecticut before the year 1743, and June 1794, we should undoubtedly
have had some record of the fact. There is no such record, and no
person remembers to have heard of such a disease, but at these periods,
prevailing in any part of the state. There are numbers of aged persons
in New Haven who remember the putrid ulcerous sore throat, small pox,
measles, dysentery, &c. raging here with great mortality, but have no
recollection of any yellow fever. Hence we may rationally conclude that
it never did appear in this state but in the years 1743 and 1794.

“It is evident, from facts before mentioned in this letter, that the
yellow fever was propagated in no other way than by contagion, and
that this is a _specific contagion_, and no more diversified, in its
operation on the human system, than that of the small pox and measles.

“If the citizens of large commercial cities were attentive in tracing
the origin of the yellow fever, on its first appearing among them,
they would often find that the disease was imported. In some instances
it would be extremely difficult to discover the origin. But the
mischief lies in this; that the inhabitants of such cities, whenever
a contagious disease makes its appearance among them, endeavour to
suppress all rumour of it, from an apprehension of alarming the
country, and injuring their commerce; unwilling to believe that there
is evil in the city, till the disease spreads in every direction. Then,
indeed, when it is too late, they are solicitous in the use of means to
arrest its progress. As it extends itself slowly at first, seasonable
exertion might both detect its source, and prevent its increase; but
when it is diffused through a city, it spreads with rapidity, and it
is no longer possible to discover where it began. But as, whenever the
yellow fever has appeared in the United States, it has always been in
sea-port towns, and originated near wharves, docks, and warehouses,
there seems to be high probability that the disease is imported.”

The evidence here seems so strong, that no counter-evidence that
can be brought appears likely to invalidate it. The coincidence of
the commencement of the fever with the arrival of the ship hath not
been denied, as in other cases; and, though it has been attempted to
prove that a fever might have arisen from the quantity of putrid or
putrescent matters at that time in the town, yet the circumstances of
those who were present at the opening of the chest of clothes being
taken with the fever, and those who were sick of it in so many cases
infecting one another, cannot by any means be overthrown. But the fact
is, that even those who contend most violently against importation, do
yet allow that it may in some cases be so; but they contend that if
proper care be taken it will not spread. Dr. Smith in his letter to Dr.
Buel says, “that infection may be brought into any place from abroad;
that, under certain circumstances of the place where it is introduced,
it becomes very destructive; but that, when these circumstances do not
exist, however the person immediately affected, if it be introduced
by a sick person, may suffer, it is harmless so far as the general
health of that place is concerned. If the subject were viewed in this
light, as most assuredly it ought to be, the question of importation or
non-importation would sink into its merited insignificance.” But, with
due respect to the memory of Dr. Smith, this must surely be accounted
a very inconsiderate mode of reasoning. In the instance he speaks of,
that of the Zephyr lately mentioned, he allows that Dr. Treat _might_
have caught the disease on board the vessel,[158] “but (says he) as _no
other_ person is known to have been infected by that vessel, and as
the Doctor communicated it to no person, the advocates for importation
would not be greatly benefited by the concession.” Surely we must
look upon the life of Dr. Treat himself to have been a matter not
entirely insignificant, and if he caught the fever by going on board,
a number of others who went in full confidence of the _impossibility_
of importation, might have done the same. As far therefore as the
prevention of such accidents can be accounted a matter of importance,
it is also of importance to believe the doctrine of imported
contagion. It is true, Dr. Smith, in the passage just quoted, adds
immediately after, that “no such concession (with regard to Dr. Treat)
is necessary;” but, in p. 104, he does make an ample concession, as we
have seen, viz. that the contagion may not only be imported, but, under
certain circumstances, _be very active and destructive_. The question
therefore rests here: Can we at all times promise that, with the utmost
care that can be taken, the circumstances of a place may not be such as
to give activity to an imported contagion? In the nature of things it
is impossible that the docks, wharves, streets and alleys of a large
town can be absolutely clean. It is equally impossible that _all_ men
can be advised to be temperate, cleanly, and neat in their lodgings;
and we are unable to determine how far people may deviate from the
_rule of right_ in those respects without danger. Before any theory
of this kind could be supported, it would be absolutely necessary to
bring an unequivocal proof that yellow fever had been in _one_ instance
at least produced by local causes; but this cannot be done. Among the
Hottentots, the dirtiest people in the world, no such disease exists.
Among the peasants of Poland, who likewise live in a very dirty manner,
their mode of life is said to produce not a fever, but a disease of
the hair, called the _plica Polonica_. In the Medical Repository,
vol. i, p. 276, Dr. Mitchill of New York describes a disease called
_elephantiasis, liktraa, or scurvy_, occasioned by loathsome,
putrefying diet, such as rotten fish, fish-livers and roe, fat and
train of whales and sea-dogs, congealed sour milk, with little or no
vegetable provisions, and by exposure to wet and cold. This disease
prevails in Iceland, in the Ferro islands, in two districts of Sweden,
and in _Madeira_; yet this disease is not the yellow fever, though it
is said to make the person afflicted with it more like “a putrefying
corpse than a living man.” The _cold_ seems to be assigned as a reason
why the disease does not assume a febrile form; but, however this may
hold with Iceland, it cannot with Sweden, where the summer is so hot,
that the sun has been said to set forests on fire. This is probably a
fable; but we are assured by Pontoppiddan, in his Natural History of
Norway, a country to the full as cold as Sweden, that in summer the
heat is very great. His expression is, that it is enough to “make a
raven gape.” As to _Madeira_, where the climate is warm, there can be
no such objection. But a particularity of this disease is, that it is
infectious. Supposing then that by any means it should be exalted into
a fever, have we any reason to imagine that in such a case it would lay
aside its infectious property? Surely not. If this then is the case
with a disease produced by the same causes with the yellow fever, we
have the very same reason to suppose that the latter is infectious, as
that the former would be so if it could lay aside its present form,
and assume that of fever. Another proof that mere dirtiness cannot at
all times produce a distemper, or even propagate its infection, may be
deduced from the sixth case quoted p. 355 from Dr. Russel, where he
says that a poor Jewish family lived in a place such as he had always
considered as one of the receptacles of contagion, yet only one in six
of those who remained in it was taken with the plague. In all cases of
plague, or of violent epidemic disorders, it has indeed been observed
that the poor were more subject to an attack than the rich. This was so
remarkable in the plague of London in 1665 that Dr. Hodges says it was
called the _poor’s plague_; and Dr. Ferriar tells us from Diemerbroeck,
that in some parts of Italy it was customary in the beginning of
a pestilence to drive out the poor; and likewise that this cruel
expedient was used at Marseilles. The bad success of the experiment at
this last place, however, shows that people of any description, and in
any circumstances, may be attacked. A very probable cause, entirely
distinct from any mode of living, may be assigned in this case, viz.
that the poor are more exposed to infection than others, both from
their circumstances and their rashness; for it will be evident to
those who converse with the most uninformed people of any country,
that the Turkish notion of predestination is far from being confined
to Mahometans. It is not, however, denied, that dirtiness, as well as
other local causes, may do much hurt, and occasion the spreading of a
disease which otherwise would not spread; because uncleanness of all
kinds seems to be the proper vehicle of infection, in which it appears
to delight to take up its abode. In the Medical Extracts, vol. ii,
p. 174, we have from Goldsmith the following anecdote concerning the
concentration of pestilential infection in the plague of London:

  [158] Webster’s Collection, p. 98.

“A pious and learned schoolmaster, who ventured to stay in the city
during the plague, and took upon himself the humane office of visiting
the sick and dying who had been deserted by better physicians, averred,
that, being once called to a poor woman, who had buried her children
of the plague, he found the room where she lay so little, that it
could scarce hold the bed on which she was stretched. However, in this
wretched abode, beside her, in an open coffin, her husband lay, who had
some time before died of the distemper, and whom she soon followed.
What shewed the peculiar _malignity_ of the air, thus suffering from
human miasmata or effluvia, was, that the contagious steams had
produced spots on the very _wall_ of their wretched apartment. And
Mr. Boyle’s own study, which was contiguous to a pest-house, was also
spotted in the same frightful manner.” This shows not how infection
may be _produced_, but how it may be concentrated in such miserable
apartments. The appearance on the walls brings to remembrance what is
said in the book of Leviticus concerning the appearance of the leprosy
in walls and clothes.

But, supposing we should allow that dirtiness may bring on a yellow
fever (and it is plain that this cannot be proved) we have, in the case
of the Busbridge Indiaman, a _demonstration_ that cleanliness cannot
keep it off.[159] This vessel sailed from England for the East Indies,
in the year 1792, much about the same time that the Hankey sailed for
the coast of Africa. She had on board 264 people in all, viz. 109
belonging to the ship’s company, 130 recruits, and 25 passengers. She
had very boisterous weather at first setting out, but crossed the
equator on the 26th of May, where the weather was sultry, with heavy
showers of rain. The disease now made its appearance first among the
recruits, and in a fortnight spread among the ship’s company. It
was common for six or seven to be attacked with it daily from the
commencement; “and in the space of twelve weeks almost every person in
the ship not only had laboured under it, but many had suffered repeated
relapses.” For several weeks the weather was hot and sultry; but, when
in the vicinity of the Cape of Good Hope, they experienced a reverse,
and were driven by a storm as high as S. lat. 42. Here the thermometer
indicated a temperature only 13° above frost, but no material change
in the disease took place. Afterwards, when returning into the warm
latitudes, they experienced the sultry heats of the Atlantic without
any change either for the better or the worse, and this for no less a
space than three months.

  [159] Annals of Medicine, vol. i, p. 166.

As to the origin of the disease, Mr. Bryce the surgeon, though
inclined to ascribe it to contagion, could not trace it to any origin
of that kind, as the vessel had been six weeks at sea before it
appeared. It “could not be ascribed to want of air or cleanliness,
as _every possible_ attention had been used to preserve these: the
different apartments were thoroughly cleaned and fumigated with wetted
gun-powder; the decks were sprinkled with boiling vinegar; and the
windsails were attentively kept in order at each hatchway. Mr. Bryce is
inclined to conjecture that a peculiar combination in the circumstances
of diet, situation, and state of the atmosphere, may have given rise to
this calamity. But the same combination of circumstances so frequently
takes place _without any fever_, that it appears much more probable
the disease had its origin either from an _imported fomes_, or from a
_fomes generated in some individual in_ the ship, from whence it was
afterwards propagated to others by _contagion_.” The disease produced
on board the ship was not contagious to the people on board another
vessel with whom they had communication, nor to the people ashore
among whom the convalescents were put, nor to new passengers taken on
board the vessel in the East Indies; circumstances certainly not a
little surprising.

It doth not therefore appear, that, without the intervention of some
other cause, mere dirtiness can produce the yellow fever. Let us
next see what can be done by confinement, want of air, or, as it has
been lately called, abstraction of oxygen. On this, however, we must
observe, that in all cases where people are allowed to breathe, their
lungs must be filled with the due quantity of _some_ elastic fluid. If
the fluid they breathe contains a smaller quantity of oxygen, it must
contain a greater quantity of something else. If a disease therefore is
produced, it must be occasioned by the _presence_ of that other fluid,
as well as by the absence of oxygen. Now, in confined air, we know that
not only the oxygen is diminished, and consequently a larger proportion
of azote or septon mixed with it, but in addition to this increased
proportion of azote, there is also a positive augmentation of the
deleterious part of the atmosphere by the effluvia from the bodies of
those who are confined. These effluvia, as we have seen, p. 90, contain
a great quantity of fixed air. Others have shown that they contain
also azote; and it may be so; but still we are sure that the fixed
air predominates. Besides this, from the breath we know that a great
quantity of aqueous moisture proceeds. Experiments on the action of
these different kinds of fluids are yet in an imperfect state, yet some
important facts relating to them are known. 1. Oxygen breathed in great
proportion produces an augmentation of heat, and proves an universal
stimulant. See p. 118. By itself it quickens the pulse.[160] 2. Pure
fixed air breathed by itself destroys life with the circumstances of
increased heat, rarefaction of the blood, and rupture of the vessels.
See p. 206. 3. The circumstances attending death by breathing azote
are not particularly recorded; but we know that by breathing an
atmosphere lowered by it the consumptive fever is not increased,
but diminished; and there is an account in the Medical Annals of a
person who was perfectly cured of a consumption by the smell of the
bilge-water of a ship. 4. It has formerly been shown, from Dr. Black’s
experiments, that, when the vapour of water is condensed in the body,
a great quantity of heat must be thus communicated to it. In confined
air therefore there is a diminution of the oxygen which produces heat;
but there is an augmentation of the fixed air and of the aqueous
moisture which increases it; so that, on the whole, the balance must
be considered as in favour of the augmentation of heat in the human
body; not to mention the quantity of sensible heat continually added to
the atmosphere by that which evaporates from the body. This position,
however, doth not stand upon the uncertain ground of theory; it is
confirmed by the following remarkable fact: Commodore Billings, who
commanded a Russian expedition fitted out by the late empress, found,
in his travels through the northeastern part of Asia, that the cold of
the atmosphere exceeded not only what was known in other climates, but
even what most people had been able to produce by freezing mixtures.
Dr. Guthrie informs us that he was unable to produce a greater degree
of cold than 36 below 0 of _Reaumur_, though assisted by 20 below 0 of
natural cold, and the power of all the freezing mixtures he knew. “How
much then (says he) was I surprised to hear Mr. Billings assert, that
some spirit thermometers which he had with him, graduated according to
_Reaumur’s_ scale, were often as low as 40° below the freezing point
of water, that is, 8 deg. below the freezing point of mercury. And
once or twice he observed them at 42 deg. below the _freezing point of
quicksilver_.[161]

  [160] In the Medical Extracts we find it recorded, that a young
  gentleman having breathed pure oxygen for several minutes, his pulse,
  which was before 64, soon beat 120, in a minute.

  [161] This account is taken from the Annals of Medicine for 1798,
  and appears in a letter from Dr. Guthrie at Petersburg to Dr. Duncan
  at Edinburgh. It is drawn up with such _astonishing_ inaccuracy,
  that we may well be surprised how the one physician should write,
  and the other print it. There seems in the first place to have been
  a mistake of Reaumur’s thermometer for Fahrenheit’s. But even this
  will not rectify the account. The _zero_ or (0) on Reaumur’s scale
  is the freezing point of water; on Fahrenheit’s it is the cold
  produced by a mixture of salt and snow, 32 degrees below the freezing
  point of water. The freezing point of quicksilver has been fixed at
  39, 39-1/2 or 40 degrees below the cold produced by salt and snow.
  When the thermometer therefore fell to 40 deg. below the freezing
  point of water, it was only eight degrees below the cold of salt
  and snow, and not equal to the congelation of mercury by more than
  thirty degrees. The difference between this and _forty-two_ degrees
  below the freezing point of quicksilver is enormous and incredible.
  It indicates a degree of cold hitherto unobserved on the face of
  the earth, and scarcely equalled by the latest experiments made
  at Hudson’s bay, where, by means of vitriolic acid and snow, the
  thermometer was made to indicate a degree of cold 40 degrees below
  the freezing point of quicksilver. The inaccuracy and confusion of
  this account, however, does not affect the subsequent part relative
  to Mr. Billings’s journey.

“During this severe cold (probably 42 below 0 of Fahrenheit) the
Nomade Tchutski (a wandering nation on the northeastern extremity
of the Asiatic continent) who were conducting him along the coast
of the Frozen ocean, in sledges drawn by rein-deer, encamped every
night on the frozen snow in low tents, which they quickly formed with
the skins of rein-deer, spreading some of them on the surface of the
snow, on which they all slept; and he assured me, that, so far from
suffering from cold during the night, the heat was so excessive in
these fur tents, where from ten to fifteen slept together, according
to its dimensions, that no one could bear even a shirt; but all lay
in a violent perspiration, naked as they were born, till dawn of day,
without the aid of fire, excepting a train-oil lamp, which lighted each
tent.”

From this account it seems pretty evident, that, by the accumulation of
animal effluvia, a heat may be communicated to the atmosphere greater
than that of the human body. We cannot suppose the heat of the tent
which put the people in a violent perspiration to have been less than
90° of Fahrenheit; and, supposing the temperature of the external
atmosphere to have been at a medium 30° below 0, there must have been
a generation of 120 degrees of heat; but the heat of the human body
does not exceed 97 degrees, and it cannot communicate more heat than
it has. But we must suppose the tents to have been capable, had they
been filled to the top, of containing twice the number who did sleep in
them. They could communicate to the air therefore only one half of 97
degrees, or 48-1/2°; the remaining 71-1/2° therefore must been derived
from the breath and perspiration of the body.[162]

  [162] Here no account is made of the heat that the very cold snow
  upon which they lay must have absorbed, which we know must have been
  very considerable, though it cannot be calculated.

Let us now attend to the consequences which must naturally and
undeniably follow from this fact. If, in such a violently cold climate,
the effluvia of fifteen human bodies could produce a heat sufficient to
induce a violent perspiration, what would they not have done had they
been in a climate where the heat of the atmosphere was upwards of an
hundred degrees greater, or between 70 and 80 above 0 of Fahrenheit?
Perhaps this was never thoroughly tried except in the black hole at
Calcutta. Here an hundred and forty-six men and one woman were enclosed
in a dungeon only 18 feet square, and consequently affording scarce
eighteen inches square to each. This happened in a very hot climate, in
the month of June; so that we cannot suppose the temperature to have
been less than 80° of Fahrenheit.

On being confined in this manner, the vital powers endeavoured, by
a most profuse perspiration, to send off the superfluous quantity
of heat thrown into the body. This was exactly what took place with
Dr. Guthrie; but, in the case of the black hole, there was, besides
the quantity of heat produced by the warmth and perspiration of the
body, _an hundred and ten_ degrees more to be added, on account of
the natural heat of the atmosphere. For we cannot suppose the heat at
Calcutta, in a sultry evening in the month of June, to have been less
than 80, which added to –30, supposed to be the temperature among the
Tchutski, makes 110°. The perspiration was extremely profuse, and was
soon accompanied with excessive thirst; nature being unable to supply
such a quantity of liquid, or this liquid to carry off the heat from
the body. The want of pure air began then to be felt by a difficulty of
breathing; and Mr. Holwell, having in despair retired from the window,
found the difficulty of breathing increase, attended by a palpitation
of the heart. Aroused by his sufferings, he returned and was relieved
by drinking some water, and having air at the window. The difficulty
of breathing diminished, and the palpitation ceased; but, finding the
thirst not to be quenched by water, he sucked his shirt-sleeves, which
were wet with sweat, and endeavoured as much as possible to catch all
of it that he could. The taste was soft and agreeable. A pungent steam
was now felt like spirit of hartshorn. A number had died, and Mr.
Holwell, once more rendered desperate, retired from the window, and
lay down upon a bench, where he soon lost all sense. Next morning only
23 survived, of whom Mr. Holwell was one. He revived on being brought
out to the fresh air, but was instantly seized with a putrid fever,
as well as all the rest of the survivors. In this situation they were
obliged to walk, loaded with fetters, to the Indian camp; at night they
were exposed to a severe rain, and the day following to a sultry sun;
yet, notwithstanding this ill treatment, they all recovered; having an
eruption of large and painful _boils_ all over the body. Mr. Holwell,
however, said that he never afterwards enjoyed good health.

Another melancholy proof of the bad consequences resulting from a want
of fresh air we have in the evidence given by Dr. Trotter, when the
question concerning the slave trade was agitated before the British
House of Commons. He deposed that the slav