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Title: Rough Ways Made Smooth - A series of familiar essays on scientific subjects
Author: Proctor, Richard A. (Richard Anthony)
Language: English
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_ROUGH WAYS MADE SMOOTH_
ROUGH WAYS MADE SMOOTH
A SERIES OF
Familiar Essays on Scientific Subjects
BY
RICHARD A. PROCTOR
[Illustration]
_NEW IMPRESSION_
LONGMANS, GREEN, AND CO.
39 PATERNOSTER ROW, LONDON
NEW YORK AND BOMBAY
1903
_All rights reserved_
'_Let knowledge grow from more to more_'
TENNYSON
PREFACE.
It is scarcely necessary for me to explain the plan of the present
work, because I have already--in introducing my 'Light Science
for Leisure Hours,' my 'Science Byways,' and my 'Pleasant Ways in
Science'--described the method on which, as I think, such treatises as
the present should be written. This work deals with similar subjects in
a similar way; but I think the experience I have acquired in writing
other works on the same plan has enabled me to avoid some defects in
the present work which I have recognised in the others.
The list of subjects indicates sufficiently the range over which the
present volume extends. Some of them might be judged by their names to
be in no way connected with science, but it will be found that none
have been treated except in their scientific significance, though in
familiar and untechnical terms.
RICHARD A. PROCTOR.
S.S. 'ARIZONA,' IRISH SEA
_October 18, 1879._
CONTENTS.
PAGE
THE SUN'S CORONA AND HIS SPOTS 1
SUN-SPOTS AND COMMERCIAL PANICS 26
NEW PLANETS NEAR THE SUN 32
RESULTS OF THE BRITISH TRANSIT EXPEDITIONS 58
THE PAST HISTORY OF OUR MOON 81
A NEW CRATER IN THE MOON 98
THE NOVEMBER METEORS 111
EXPECTED METEOR SHOWER 117
COLD WINTERS 125
OXFORD AND CAMBRIDGE ROWING 148
ROWING STYLES 169
ARTIFICIAL SOMNAMBULISM 178
HEREDITARY TRAITS 205
BODILY ILLNESS AS A MENTAL STIMULANT 236
DUAL CONSCIOUSNESS 259
ELECTRIC LIGHTING 289
ROUGH WAYS MADE SMOOTH.
_THE SUN'S CORONA AND HIS SPOTS._
One of the most important results of observations made upon the eclipse
of July 29, 1878, indicates the existence of a law of sympathy, so to
speak, between the solar corona and the sun-spots. The inquiry into
this relation seems to me likely to lead to a very interesting series
of researches, from which may possibly result an interpretation not
only of the relation itself, should it be found really to exist, but
of the mystery of the sun-spot period. I speak of the sun-spot period
as mysterious, because even if we admit (which I think we cannot do)
that the sun-spots are produced in some way by the action of the
planets upon the sun, it would still remain altogether a mystery
how this action operated. When all the known facts respecting the
sun-spots are carefully considered, no theory yet advanced respecting
them seems at all satisfactory, while no approach even has been
made to an explanation of their periodic increase and diminution in
number. This seems to me one of the most interesting problems which
astronomers have at present to deal with; nor do I despair of seeing
it satisfactorily solved within no very long interval of time. Should
the recognition of a sympathy between the corona and the sun-spots be
satisfactorily established, an important step in advance will have been
made,--possibly even the key to the enigma will be found to have been
discovered.
I propose now to consider, first, whether the evidence we have on this
subject is sufficient, and afterwards to discuss some of the ideas
suggested by the relations which have been recognised as existing
between the sun-spots, the sierra, the coloured prominences, and the
zodiacal light.
The evidence from the recent eclipses indicates beyond all possibility
of doubt or question, that during the years when sun-spots were
numerous, in 1870 and 1871, the corona, at least on the days of the
total solar eclipses in those years, presented an appearance entirely
different from that of the corona seen on July 29, 1878, when the sun
was almost free from spots. This will be more fully indicated further
on. At present it is necessary to notice only (1) that whereas in 1870
and 1871 the inner corona extended at least 250,000 miles from the
sun, it reached only to a height of some 70,000 miles in 1878; (2) in
1870 and 1871 it possessed a very complicated structure, whereas in
1878 the definite structure could be recognised only in two parts of
the inner corona; (3) in 1871 the corona was pink, whereas in 1878
it was pearly white; (4) the corona was ten times brighter in 1871
than in 1878; lastly, in 1871 the light of the corona came in part
from glowing gas, whereas in July, 1878, the light came chiefly, if
not wholly, from glowing solid or liquid matter. I must here point
out, that the evidence of change, however satisfactory in itself,
would be quite insufficient to establish the general theory that the
corona sympathises with the solar photosphere in the special manner
suggested by the recent eclipse observations. There are few practices
more unscientific, or more likely to lead to erroneous theorising, than
that of basing a general theory on a small number of observations.
In this case we have, in fact, but a single observed correspondence,
though the observations establishing it form a series. It has been
shown that so far as the special sun-spot period from the minimum of
1867 to the minimum of 1878 is concerned, there has been a certain
correspondence between the aspect of the corona and the state of
the sun's surface, with regard to spots. To assume from that single
correspondence that the corona and the sun-spots are related in the
same way, would be hazardous in the extreme. We may indeed find, when
we consider other matters, that the probability of a general relation
of this sort existing is so great antecedently, that but slight direct
evidence would be required to establish the existence of the relation.
But it must be remembered that before the eclipse of 1878 was observed,
with the special result I have noticed, few were bold enough to assert
the probable existence of any such relationship; and certainly no one
asserted that the probability was very strong. I believe, indeed, that
no one spoke more definitely in favour of the theory that the corona
probably sympathises with the sun-spots than I did myself before the
recent eclipse; but certainly I should not then have been willing to
say that I considered the evidence very strong.
We must then look for evidence of a more satisfactory kind.
Now, although during the two centuries preceding the invention of the
spectroscope and the initiation of the solar physical researches now in
progress, observations of eclipses were not very carefully conducted,
yet we have some records of the appearance of the corona on different
occasions, which, combined with the known law of sun-spot periodicity,
may enable us to generalise more safely than we could from observations
during the present spot-period, though these observations have been far
more exact than the older ones. I propose to examine some of these.
Necessarily I must make some selection. I need hardly say that even
if there were no such relation as that which seems to be indicated by
recent observations, and if my purpose were simply to prove, either
that such a relation exists or that it does not, I could very readily
bring before the reader of these pages what would seem like the most
satisfactory evidence that the relation is real. I must ask him to
believe, however, that my purpose is to ascertain where the truth lies.
I shall neither introduce any observation of the corona because it
seems specially favourable to the theory that the corona sympathises
with the photosphere, nor omit any, because it seems definitely opposed
to that theory. To prevent any possibility of being unconsciously
prejudiced, I shall take a series of coronal observations collected
together by myself, on account of their intrinsic interest, several
years ago, when I had not in my thoughts any theory respecting periodic
changes in the corona--the series, namely, which is included in the
sixth chapter of my treatise on the sun. Each of these observations
I shall consider in connection with the known condition of the sun
as to spots, and those results which seem to bear _clearly_, whether
favourably or unfavourably, on the theory we are enquiring into, I
shall bring before the reader.
Kepler, whose attention had been specially drawn to the subject of the
light seen round the sun during total eclipse, by certain statements
which Clavius had made respecting the eclipse of 1567, describes the
eclipse of 1605 in the following terms:--'The whole body of the sun
was completely covered for a short time, but around it there shone a
brilliant light of a reddish hue and uniform breadth, which occupied a
considerable portion of the heavens.' The corona thus seen may fairly
be assumed to have resembled in extent that of 1871. A bright corona,
reaching like that seen during the eclipse of July 1878 to a height
of only about 70,000 miles from the sun's surface, would certainly
not have been described by Kepler as occupying a considerable portion
of the heavens, for a height of 70,000 miles would correspond only to
about a twelfth of the sun's diameter; and a ring so narrow would be
described very differently. It seems, then, that in 1605 a corona was
seen which corresponded with that observed when the sun has had many
spots on his surface. Now we have no record of the condition of the
sun with regard to spots in 1605; but we know that the year 1615 was
one of many spots, and the year 1610 one of few spots; whence we may
conclude safely that the year 1605 was one of many spots. This case
then is in favour of the theory we are examining.
In passing we may ask whether the observation by Clavius which had
perplexed Kepler, may not throw some light on our subject. Clavius says
that the eclipse of 1567 which should have been total was annular. The
usual explanation of this has been that the corona was intensely bright
close to the sun. And though Kepler considered that his own observation
of a broad reddish corona satisfactorily removed Clavius's difficulty,
it seems tolerably clear that the corona seen by Clavius must have
been very unlike the corona seen by Kepler. In fact the former must
have been like the corona seen in July, 1878, much smaller than the
average, but correspondingly increased in lustre. Now with regard to
the sun-spot period we can go back to the year 1567, though not quite
so securely as we could wish. Taking the average sun-spot period at
eleven years, and calculating back from the minimum of spots in the
year 1610, we get four years of minimum solar disturbance, 1599, 1588,
1577, and 1566. We should have obtained the same result if we had used
the more exact period, eleven one-ninth years, and had taken 1610·8 for
the epoch of least solar disturbance (1610·8 meaning about the middle
of October, 1610). Thus the year 1567 was a year of few sun-spots,
probably occupying almost exactly the same position in the sun spot
period as the year 1878. Clavius's observation, then, is in favour of
our theory.
But another observation between Clavius's and Kepler's may here be
noticed. Jensenius, who observed the eclipse of 1598 at Torgau in
Germany, noticed that, at the time of mid-totality, a bright light
shone round the moon. On this occasion, remarks Grant, the phenomenon
was generally supposed to arise from a defect in the totality of the
eclipse, though Kepler strenuously contended that such an explanation
was at variance with the relation between the values of the apparent
diameters of the sun and moon as computed for the time of the eclipse
by aid of the solar and lunar tables. The corona, then, must have
resembled that seen by Clavius, and since the year 1598 must have been
very near the time of fewest spots, this observation accords with the
theory we are examining.
The next observation is that made by Wyberd during the eclipse of 1652.
Here there is a difficulty arising from the strange way in which the
sun-spots behaved during the interval from 1645 to 1679. According
to M. Wolf, whose investigation of the subject has been very close
and searching, there was a maximum of sun-spots in 1639 followed
by a minimum in 1645, the usual interval of about six years having
elapsed; but there came a maximum in 1655, ten years later, followed
by a minimum in 1666, eleven years later, so that actually twenty-one
years would seem to have elapsed between successive minima (1645 and
1666). Then came a maximum in 1675, nine years later, and a minimum in
1679, four years later. Between the maxima of 1639 and 1675, including
two spot periods, an interval of thirty-six years elapsed. There is
no other instance on record, so far as I know, of so long an interval
as this for two spot-periods. In passing, I would notice how little
this circumstance accords with the theory that the sun-spots follow
an exact law, or that from observations of the sun, means can ever be
found for forming a trustworthy system of weather prediction, even if
we assumed (which has always seemed to me a very daring assumption),
that terrestrial weather is directly dependent on the progress of the
sun-spot period. But here the irregularity of the spot changes affects
us only as preventing us from determining or even from guessing what
may have been the condition of the sun's surface in the year 1652.
This year followed by seven years a period of minimum disturbance, and
preceded by three years a period of maximum disturbance; but it would
be unsafe to assume that the sun's condition in 1652 was nearer that
of maximum than that of minimum disturbance. We must pass over Wyberd's
observations of the corona in 1652, at least until some direct evidence
as to the sun's condition shall have been obtained from the papers or
writings of the observers of that year. I note only that Wyberd saw a
corona of very limited extent, having indeed a height not half so great
as that of many prominences which have been observed during recent
eclipses. If the theory we are examining should be established beyond
dispute, we should be led to infer that the year 1652 was in reality
a year of minimum solar disturbance. Perhaps by throwing in such a
minimum between 1645 and 1666, with of course a corresponding maximum,
the wild irregularity of the sun-spot changes between 1645 and 1679
would be to some degree diminished.
We are now approaching times when more satisfactory observations were
made upon the corona, and when also we have more complete records of
the aspect of the sun's surface.
In 1706 Plantade and Capies saw a bright ring of white light extending
round the eclipsed sun to a distance of about 85,000 miles, but merging
into a fainter light, which extended no less than four degrees from
the eclipsed sun, fading off insensibly until its light was lost in
the obscure background of the sky. This corresponds unmistakably
with such a corona as we should expect only to see at a time of many
sun-spots, if the theory we are examining is sound. Turning to Wolf's
list, we find that the year 1705 is marked as a year of maximum solar
disturbance, and the year 1712 as that of the next minimum. Therefore
1706 was a year of many sun-spots--in fact, 1706 may have been the year
of actual maximum disturbance, for it is within the limits of doubt
indicated by Wolf. Certainly a corona extending so far as that which
Plantade and Capies saw would imply an altogether exceptional degree of
solar disturbance, if the theory we are considering is correct.
In 1715 Halley gave the following description of the corona:--'A few
seconds before the sun was all hid, there discovered itself round the
moon a luminous ring about a digit' (a twelfth) 'or perhaps a tenth
part of the moon's diameter in breadth. It was of a pale whiteness or
rather pearl colour, seeming to me a little tinged with the colours
of the Iris, and to be concentric with the moon.' He added that the
ring appeared much whiter and brighter near the body of the moon
than at a distance from it, and that its exterior boundary was very
ill-defined, seeming to be determined only by the extreme rarity of
the luminous matter. The French astronomer Louville gave a similar
account of the appearance of the ring. He added, however, that 'there
were interruptions in its brightness, causing it to resemble the
radial glory with which painters encircle the heads of the saints.'
The smallness of the corona on this occasion corresponds with the
description of the corona seen in July 1878; and though Louville's
description of gaps is suggestive of a somewhat different aspect,
yet, on the whole, the corona seen in 1715 more closely resembles
one which would be seen at a time of minimum solar disturbance, if
our theory can be trusted, than one which would be seen at a time of
maximum disturbance. Wolf's list puts the year 1712 as one of minimum
disturbance, with one year of doubt either way, and the middle of the
year 1817 as the epoch of maximum disturbance, with a similar range of
uncertainty. The case, then, is doubtful, but on the whole inclines
to being unfavourable. I may remark that because of its unfavourable
nature, I departed from the rule I had set myself, of taking only the
cases included in my treatise on the sun. For the corona of 1715 is not
described in that treatise, as indeed affording no evidence respecting
this solar appendage. The evidence given in this case is probably
affected in some degree by the unfavourable atmospheric conditions
under which Halley certainly, and Louville probably, observed the
eclipse. In any case the evidence is not strong; only I would call
attention here to the circumstance that if, as we proceed, we _should_
come to a case in which the evidence is plainly against the theory
we are examining, we must give up the theory at once. For one case
of discordance does more to destroy a theory respecting association
between such and such phenomena, than a hundred cases of agreement
would do in the way of confirming it.
In 1724, Maraldi noticed that the corona was broadest first on the side
towards which the moon was advancing, and afterwards on the side which
the moon was leaving. From this we may infer that the corona was only a
narrow ring on that occasion, since otherwise the slight difference of
breadth due to the moon's eccentric position at the beginning and end
of totality would not have been noticeable. Now, the year 1723 was one
of minimum disturbance, with one year of doubt either way. Thus 1724
was certainly a year of few sun-spots, and may have been the actual
year of minimum disturbance. The corona then presented an appearance
according with the theory we are considering.
Few eclipses have been better observed than that of the year 1733.
The Royal Society of Sweden invited all who could spare the time to
assist, as far as their ability permitted, in recording the phenomena
presented during totality. The pastor of Stona Malm states that at
Catherinesholm, there was a ring around the sun about 70,000 miles in
height. (Of course these are not his exact words; what he actually
stated was that the ring was about a digit in breadth.) This is the
exact height assigned to the coronal ring by the observers of the
eclipse of last year. The ring seemed to be of a reddish colour.
Another clergyman, Vallerius, states also that the ring was of this
colour, but adds that at a considerable distance from the sun it had
a greenish hue. This suggests the idea that the outer corona was seen
also by Vallerius, and that it had considerable breadth. The reddish
colour of the inner light portion would correspond to the colour it
would have if it consisted in the main of glowing hydrogen. If that
really was its constitution, then the theory advanced by one observer
of the last eclipse, that at the time of minimum solar disturbance the
glowing hydrogen is withdrawn from the corona, would be shown to be
incorrect. For 1733 was the actual year of minimum solar disturbance.
The pastor of Smoland states that 'during the total obscuration the
edge of the moon's disc resembled gilded brass, and the faint ring
round it emitted rays in an upward as well as in a downward direction,
similar to those seen beneath the sun when a shower of rain is
impending.' The mathematical lecturer of the Academy of Charles-stadt,
M. Edstrom, observed these rays with special attention: he says that
'they plainly maintained the same position, until they vanished along
with the ring upon the re-appearance of the sun.' On the other hand,
at Lincopia no rays were seen. On the whole it seems clear from the
accounts of this eclipse that the inner corona was bright and narrow;
rays issued from the outer faint ring; but they were very delicate
phenomena, easily concealed by atmospheric haze, and thus were not
everywhere observed. As rays were seen in July 1878, there is nothing
in the evidence afforded by the eclipse of 1733, occurring at a time
of few spots, which opposes itself definitely to the theory we are
considering. But the reddish colour of the corona as already noticed
is a doubtful feature: in July, 1878, the bright inner corona was of a
pearl colour and lustre.
During the eclipse of February, 1766, the corona presented four
luminous expansions, and seems to have presented a greater expansion
than we should expect in a year of minimum solar disturbance. Such,
however, the year 1766 certainly was. The evidence in this case is
unfavourable to our theory--not quite decisively so, but strongly.
For we should expect that in the year of actual minimum disturbance
the corona would be even narrower than in the year 1878, which was
the year following that of least disturbance. And again, a strongly
distinctive feature in the corona of July, 1878, was the absence of
wide expansions, such as were seen in 1870 and 1871. Now if this
peculiarity should really be attributed to the relation existing
between the corona and the sun-spots, we should infer that in 1766
the corona would have been still more markedly uniform in shape. The
existence of four well marked expansions on that occasion forces us
to assume that either the relation referred to has no real existence,
or else that the corona may change from week to week as the condition
of the sun's surface changes, and that in February, 1766, the sun was
temporarily disturbed, though the year, as a whole, was one of minimum
disturbance. But as the epoch of actual minimum was the middle of 1766,
February 1766 should have been a time of very slight disturbance. I
do not know of any observations of the sun recorded for the month of
February, 1766. On the whole, the eclipse of 1766 must be regarded as
throwing grave doubt on the relation assumed by our theory as existing
between the corona and the sun-spots; and as tending to suggest
that some wider law must be in question than the one we have been
considering--if any association really exists.
The account given by Don Antonio d'Ulloa of the appearance presented
by the corona during the total eclipse of 1778, is rendered doubtful
by his reference to an apparent rotatory motion of the normal rays.
He says that about five or six seconds after totality had begun, a
brilliant luminous ring was seen around the dark body of the moon.
The ring became brighter as the middle of totality approached. 'About
the middle of the eclipse, the breadth of the ring was equal to
about a sixth of the moon's diameter. There seemed to issue from it
a great number of rays of unequal length, which could be discerned
to a distance equal to the moon's diameter.' Then comes the part of
d'Ulloa's description which seems difficult to accept. He says that the
corona 'seemed to be endued with a rapid rotatory motion, which caused
it to resemble a firework turning round its centre.' The colour of
the light, he proceeds, 'was not uniform throughout the whole breadth
of the ring. Towards the margin of the moon's disc it appeared of a
reddish hue; then it changed to a pale yellow, and from the middle
to the outer border the yellow gradually became fainter, until at
length it seemed almost quite white.' Setting aside the rays and their
rotation, d'Ulloa's account of the inner corona may be accepted as
satisfactory. The height of this ring was, it seems, about 140,000
miles, or twice that of the ring seen in July 1878. As the year 1779
was one of maximum solar disturbance, there were doubtless many spots
in 1778; and the aspect of the corona accorded well with the theory
that the corona expands as the number of sun-spots increases.
We come now to three eclipses which are especially interesting as
having been all carefully observed, some observers having seen all
three,--the eclipses, namely, of 1842, 1851, and 1860. Unfortunately
the eclipses of 1842 and 1851 occurred when the sun-spots were neither
at their greatest nor at their least degree of frequency. For a maximum
of sun-spots occurred in 1837, and a minimum in 1844, so that 1842 was
on what may be called the descending slope of a sun-spot wave, nearer
the hollow than the crest, but not very near either: again, a maximum
occurred in 1848, and a minimum in 1856, so that 1851 was also on the
descending slope of a sun-spot wave, rather nearer the crest than the
hollow, but one may fairly say about midway between them. Still it is
essential in an inquiry of this sort to consider intermediate cases.
We must not only apply the _comparentia ad intellectum instantiarum
convenientium_, but also the _comparentia instantiarum secundum magis
ac minus_. If the existence of great solar disturbances causes the
corona to be greatly enlarged, as compared with the corona seen when
the sun shows no spots, we should expect to find the corona moderately
enlarged only when the sun shows a considerable but not the maximum
number of spots. And again, it is conceivable that we may find some
noteworthy difference between the aspect of the corona when sun-spots
are diminishing in number, and its aspect when they are increasing.
This point seems the more to need investigation when we note that
the evidence derived from eclipses occurring near the time either
of maximum or of minimum solar disturbance has not been altogether
satisfactory. It may be that we may find an explanation of the
discrepancies we have recognised, in some distinction between the state
of the corona when spots are increasing and when they are diminishing
in number.
It is noteworthy that several careful observers of the corona in 1842
believed that they could recognise motion in the coronal rays. Francis
Baily compared the appearance of the corona to the flickering light of
a gas illumination. O. Struve also was much struck by the appearance of
violent agitation in the light of the ring. It seems probable that the
appearance was due to movements in that part of our atmosphere through
which the corona was observed. The extent of the corona was variously
estimated by different observers. Petit, at Montpelier, assigned to
it a breadth corresponding to a height of about 200,000 miles; Baily
a height of about 500,000 miles; and O. Struve a height of more than
800,000 miles. The last-named observer also recognised luminous
expansions extending fully four degrees (corresponding to nearly seven
million miles) from the sun. Picozzi, at Milan, noticed two jets of
light, which were seen also by observers in France. Rays also were seen
by Mauvais at Perpignan, and by Baily at Paria. But Airy, observing the
corona from the Superga, could see no radiation; he says 'although a
slight radiation might have been perceptible, it was not sufficiently
intense to affect in a sensible degree the annular structure by which
the luminous appearance was plainly distinguished.' These varieties
in the aspect of the corona were doubtless due to varieties in the
condition of the atmosphere through which the corona was seen. Now it
cannot be questioned that, so far as extension is concerned, the corona
seen in 1842 was one which, if the theory we are considering were
sound, we should expect to see near the time of maximum rather than of
minimum solar disturbance. On the other hand, in brightness the corona
of 1842 resembled, if it did not surpass, that of July 1878.
'I had imagined,' says Baily, 'that the corona, as to its brilliant or
luminous appearance, would not be greater than that faint crepuscular
light which sometimes takes place (_sic_) in a summer evening, and
that it would encircle the moon like a ring. I was therefore somewhat
surprised and astonished at the splendid scene which now so suddenly
burst upon my view.'
The light of the corona was so bright, O. Struve states, that the naked
eye could scarcely endure it; 'many could not believe, indeed, that the
eclipse was total, so strongly did the corona's light resemble direct
sunlight.' Thus while as to extent the corona in 1842 presented the
appearance to be expected at the time of maximum solar disturbance, if
our theory is sound, its brightness was that corresponding to a time
of minimum disturbance. Its structure corresponded with the former
condition. The light of the corona was not uniform, nor merely marked
by radiations, but in several places interlacing lines of light could
be seen. Arago, at Perpignan, observed with the unaided eye a region
of the corona where the structure was as of intertwined jets giving an
appearance resembling a hank of thread in disorder.
Certainly, for an eclipse occurring two years from the time of minimum,
and five years from the time of maximum disturbance, that of July,
1842,[1] has not supplied evidence favouring the theory with which we
started. Whether any other theory of association between the corona and
the sun-spots will better accord with the evidence hitherto collected
remains to be seen.
Turn we now to the eclipse of 1851, occurring nearly midway between
the epochs of maximum solar disturbance (1848) and minimum solar
disturbance (1856). I take the account given by Airy, our Government
astronomer, as he was one of the observers of the eclipse of 1842.
'The corona was far broader,' he says, 'than that which I saw in
1842. Roughly speaking, the breadth was little less than the moon's
diameter, but its outline was very irregular. I did not notice any
beams projecting from it which deserved notice as much more conspicuous
than the others; but the whole was beamy, radiated in structure, and
terminated--though very indefinitely--in a way which reminded me of the
ornament frequently placed round a mariner's compass. Its colour was
white, or resembling that of Venus. I saw no flickering or unsteadiness
of light. It was not separated from the moon by any interval, nor had
it any annular structure. It looked like a radiated luminous cloud
behind the moon.'
The corona thus described belongs to that which our theory associates
with the period of maximum rather than of minimum solar disturbance.
Definite peculiarities of structure seem to have been more numerous and
better marked than in 1842. It accords with our theory that 1851 was
a year of greater solar disturbance than was observed in 1842, as the
following numbers show:--
Days of Days without New groups
observation spots observed
1842 307 64 68
1851 308 0 141
1860 332 0 211
I have included the year 1860, as we now proceed to consider the corona
then seen by Airy. The year 1860 did not differ very markedly, it will
be observed, from 1851, as regards the number of new groups of spots
observed by Schwabe, especially when account is taken of the number of
days in which the sun was observed in these two years. But 1860 was a
year of maximum solar disturbance, whereas 1851 was not.[2]
Airy remarks of the corona in 1860:--'It gave a considerable body,
but I did not remark either by eye-view or by telescope-view
anything annular in its structure; it appeared to me to resemble,
with some irregularities (as I stated in 1851), the ornament round a
compass-card.'
Bruhns of Leipsic noted that the corona shone with an intense white
light, so lustrous as to dim the protuberances. He noticed that a ray
shot out to a distance of about one degree indicating a distance of at
least 1,500,000 miles from the sun's surface. This was unquestionably
a coronal appendage as neither the direction nor the length of the ray
varied for ten seconds, during which Bruhns directed his attention to
it. Its light was considerably feebler than that of the corona, which
was of a glowing white, and seemed to coruscate or twinkle. Bruhns
assigned to the inner corona a height varying from about 40,000 to
about 80,000 miles. But this was unquestionably far short of the true
height. In fact, Secchi's photographs show the corona extending to
a distance of at least 175,000 miles from the surface of the sun.
Therefore probably what Bruhns calls the base of the corona was in
reality only the prominence region, and the inner corona was that which
he describes as varying in breadth or height from nearly one-half to
a quarter of a degree--that is from about 800,000 to about 400,000
miles. De la Rue gives a somewhat similar general description of the
corona seen in 1860. He remarks that it was extremely bright near the
moon's body, and of a silvery whiteness. The picture of the corona by
Feilitsch (given at p. 343 of my book on the Sun) accords with these
descriptions.
On the whole, the eclipse of 1860 affords evidence according well with
the theory we have been considering, except as regards the brightness
and the colour of the corona, which correspond more closely with what
was observed in July, 1878, with the lustre and colour of the corona
in 1870 and 1871. In this respect, it is singular that the eclipse of
1867, which occurred (see preceding note) when the sun spots were fewer
in number, presented a decided contrast to that of 1860,--the contrast
being, however, precisely the reverse of that which our theory would
require, if the colour and brightness of the corona be considered
essential features of any law of association.
Herr Grosch, describing the corona of 1867, says, 'There appeared
around the moon a reddish glimmering light similar to that of the
aurora, and almost simultaneously with this (I mean very shortly after
it) the corona.' It is clear, however, from what follows, that the
reddish light was what is now commonly called the inner corona, which
last July, when the sun was in almost exactly the same condition as
regards the spots, was pearly white and intensely bright. 'This reddish
glimmer,' he proceeds, 'which surrounded the moon with a border of the
breadth of at most five minutes' (about 140,000 miles) 'was not sharply
bounded in any part, but was extremely diffused and less distinct in
the neighbourhood of the poles.' Of the outer corona he remarks that
'its apparent height amounted to about 280,000 miles opposite the
solar poles, but opposite the polar equator to about 670,000 miles. Its
light was white. This white light was not in the least radiated itself,
but it had the appearance of rays penetrating through it; or rather as
if rays ran over it, forming symmetrical pencils diverging outwards,
and passing far beyond the boundary of the white light. These rays had
a more bluish appearance, and might best be compared to those produced
by a great electro-magnetic light. Their similarity to these, indeed,
was so striking, that under other circumstances I should have taken
them for such, shining at a great distance. The view of the corona I
have described is that seen with the naked eye.... In the white light
of the corona, close upon the moon's edge, there appeared several dark
curves. They were symmetrically arched towards the east and west,
sharply drawn, and resembling in tint lines drawn with a lead pencil
upon white paper.... Beginning at a distance of one minute (about
26,000 miles), they could be traced up to a distance of about nine
minutes (some 236,000 miles) from the moon's edge.'
Almost all the features observed in this case correspond closely with
those noted and photographed during the eclipse of December, 1871.
In other words the corona seen in 1867, when the sun was passing
through the period of least solar disturbance, closely resembled the
corona seen in 1871, when the sun was nearly in its stage of greatest
disturbance. Even the spectroscopic evidence obtained in 1871 and July,
1878, may be so extended as to show with extreme probability what would
have been seen in 1867 if spectroscopic analysis had then been applied.
We cannot doubt that the reddish inner corona, extending to a height of
about 140,000 miles, would have been found under spectroscopic analysis
to shine in part with the light of glowing hydrogen, as the reddish
corona of 1871 did. The white corona of July, 1878, on the contrary,
shone only with such light as comes from glowing solid or liquid
matter. Here then, again, the evidence is unfavourable to our theory;
for the corona in 1867 should have closely resembled the corona of
1878, if this theory were sound.
It would be idle, I think, to seek for farther evidence either in
favour of the theory we originally proposed to discuss, or against it:
for the evidence of the eclipse of 1867 disposes finally of the theory
in that form. I may note in passing that the eclipse of 1868 gave
evidence almost equally unfavourable to the theory, while the evidence
given by the eclipse of 1869 was neutral. It will be desirable,
however, to consider, before concluding our inquiry, the evidence
obtained in 1871 and last July, in order that we may see what, after
all, that evidence may be regarded as fairly proving with regard to
coronal variations.
First, however, as I have considered two eclipses which occurred when
the sun spots were decreasing in number--namely, those of 1842 and
1851, midway (roughly speaking) between the crest and hollow of the
sun-spot wave on its descending slope, it may be well to consider an
eclipse which was similarly situated with respect to the ascending
slope of a sun-spot wave. I take, then, the eclipse of 1858, as seen in
Brazil by Liais. The picture drawn by this observer is one of the most
remarkable views of the corona ever obtained. It is given at p. 339 of
my book on the Sun. Formerly it was the custom to deride this drawing,
but since the eclipse of 1871, when the corona was photographed, it
has been admitted that Liais's drawing may be accepted as thoroughly
trustworthy. It shows a wonderfully complex corona, like that of 1871,
extending some 700,000 miles from the sun, and corresponding in all
respects with such a corona as our theory (if established) would have
associated with the stage of maximum solar disturbance. As in this
respect the eclipse of 1858, when sun-spots were increasing, resembled
those of 1842 and 1851, when sun-spots were diminishing in number,
we find no trace of any law of association depending on the rate of
increase or diminution of solar disturbance.
If we limited our attention to the eclipses of 1871 and of July, 1878,
we should unquestionably be led to adopt the belief that the corona
during a year of many spots differs markedly from the corona when the
sun shows few spots, or none. So far as the aspect of the corona is
concerned, I take the description given by the same observer in both
cases, as the comparison is thus freed as far as possible from the
effect of personal differences.
Mr. Lockyer recognised in 1871 a corona resembling a star-like
decoration, with its rays arranged almost symmetrically--three
above and three below two dark spaces or rifts at the extremity of
a horizontal diameter. The rays were built up of innumerable bright
lines of different length, with more or less dark spaces between
them. Near the sun this structure was lost in the brightness of the
central ring, or inner corona. In the telescope he saw thousands of
interlacing filaments, varying in intensity. The rays so definite
to the eye were not seen in the telescope. The complex structure of
interlacing filaments could be traced only to a height of some five or
six minutes (from 135,000 to 165,000 miles) from the sun, there dying
out suddenly. The spectroscope showed that the inner corona, to this
height at least (but Respighi's spectroscopic observations prove the
same for a much greater distance from the sun), was formed in part
of glowing gas--hydrogen--and the vapour of some as yet undetermined
substance, shining with light of a green tint, corresponding to
1474 of Kirchhoff's scale. But also a part of the coronal light
came from matter which reflected sunlight; for its spectrum was the
rainbow-tinted streak crossed by dark lines, which we obtain from any
object illuminated by the sun's rays. It should be added that the
photographs of the corona in 1871 show the three great rays above and
three below, forming the appearance as of a star-like decoration,
described by Mr. Lockyer; insomuch as it is rather strange to find Mr.
Lockyer remarking that 'the difference between the photographic and
the visible corona came out strongly, ... and the non solar origin of
the radial structure was conclusively established.' The resemblance
is, indeed, not indicated in the rough copy of the photographs which
illustrates Mr. Lockyer's paper; but it is clearly seen in the
photographs themselves, and in the fine engraving which has been formed
from them for the illustration of the volume which the Astronomical
Society proposes to issue (some time in the present century, perhaps).
Now, in July, 1878, the corona presented an entirely different
appearance. Mr. Lockyer, in a telegram sent to the _Daily News_,
describes it as small, of pearly lustre, and having indications of
definite structure in two places only. Several long rays were seen; but
the inner corona was estimated as extending to a height of about 70,000
miles from the sun's surface. The most remarkable change, however,
was that which had taken place in the character of the corona's
spectrum--or, in other words, in the physical structure of the corona.
The bright lines or bright images of the inner corona (according as
it was examined through a slit or without one) were not seen in July,
1878, showing that no part, or at least no appreciable part, of its
light came from glowing gaseous matter. But also the dark lines seen by
Janssen in 1871 were wanting on this occasion, showing that the corona
did not shine appreciably by reflecting sunlight. The spectrum was, in
fine, a continuous rainbow-tinted streak, such as that given by glowing
solid or liquid matter.
The inference clearly is: 1. That in July, 1878, the gaseous matter
which had been present in the corona in 1871 was either entirely absent
or greatly reduced in quantity; 2. The particles of solid or liquid
(but probably solid) matter which, by reflecting sunlight, produced a
considerable portion of the corona's light in 1871, were glowing with
heat in July, 1878, and shone in the main with this inherent light;
and 3. The entire corona was greatly reduced in size in July, 1878, as
compared with that which formed the 'star-like decoration' around the
black body of the moon in December, 1871.
We cannot, however, accept the theory that such a corona as was seen
in 1871 invariably surrounds the sun in years of great disturbance,
while the corona of last month is the typical corona for years of
small solar disturbance. The generalisation is flatly contradicted
by the evidence which I have presented in the preceding pages. It
may be that such a corona as was seen in 1871 is common in years of
great disturbance, just as spots are then more common, though not
always present; while such a corona as was seen in July, 1878, is more
common in years of small disturbance, just as days when the sun is
wholly without spots are then more common, though from time to time
several spots, and sometimes very large spots, are seen in such years.
On the whole, I think the evidence I have collected favours rather
strongly the inference that an association of this sort really exists
between the corona and the sun-spots. It would, however, be unsafe at
present to generalise even to this extent; while certainly the wide
generalisation telegraphed to Europe from America as the great result
of the eclipse observations in July, 1878, must unhesitatingly be
rejected.
It remains to be considered how science may hope to obtain more
trustworthy evidence than we yet have respecting the corona and its
changes of form, extent, lustre, and physical constitution. In the case
of the prominences, we have the means of making systematic observations
on every fine, clear day. It has been, indeed, through observations
thus effected by the spectroscopic method that an association has been
recognised between the number, size, and brilliancy of the prominences
on the one hand, and the number, size, and activity of the sun-spots
on the other. But in the case of the corona, we are as yet unable to
make any observations except at the time of total solar eclipse. It
seems almost impossible to hope that any means can be devised for
seeing the corona at any other time. Of course, without the aid of the
spectroscope the corona, as ordinarily seen during total eclipses, must
be entirely invisible when the sun is shining in full splendour. No one
acquainted with even the merest elements of optics could hope to see
the corona with an ordinary telescope at such a time. The spectroscope,
again, would not help in the slightest degree to show such a corona as
was shining in July, 1878. For the power of the spectroscope to show
objects which under ordinary conditions are invisible, depends on the
separation of rays of certain tints from the rays of all the colours
of the rainbow, which make up solar light; and as the corona in July,
1878, shone with all the colours of the rainbow, and not with certain
special tints, the power of the spectroscope would be thrown away on a
corona of that kind. All that we can ever hope to do is to discern the
gaseous corona when, as in 1871, it is well developed, by spectroscopic
appliances more effective for that purpose than any which have hitherto
been adopted; for all which have as yet been adopted have failed.
Now, the difficulty of the problem will be recognised when we remember
that the strongest tints of the corona's light--the green tint
classified as 1474 Kirchhoff--has been specially but ineffectually
searched for in the sun's neighbourhood with the most powerful
spectroscopic appliances yet employed in the study of the coloured
prominences. In other words, when the light of our own air over the
region occupied by the corona has been diluted as far as possible
by spectroscopic contrivances, the strongest of the special coronal
tints has yet failed to show through the diluted spectrum of the sky.
Again, we have even stronger evidence of the difficulty of the task in
the spectroscopic observations made by Respighi during the eclipse of
1871. The instrument, or I should rather, perhaps, say the arrangement,
which during mid totality showed the green image of the corona to a
height of about 280,000 miles, did not show any green ring at all at
the beginning of totality. In other words, so faint is the light of the
gaseous corona, even at its brightest part, close to the sun, that the
faint residual atmospheric light which illuminates the sky over the
eclipsed sun at the beginning of totality sufficed to obliterate this
part of the coronal light.
Whether with any combination specially directed to meet the
difficulties of this observation, the gaseous corona can be rendered
discernible, remains to be seen. I must confess my own hopes that the
problem will ever be successfully dealt with are very slight, though
not absolutely evanescent. It seems to me barely possible that the
problem might be successfully attacked in the following way. Using a
telescope of small size, for the larger the telescope the fainter is
the image (because of greater loss of light by absorption), let the
image of the sun be received in a small, perfectly darkened camera
attached to the eye-end of the telescope. Now if the image of the sun
were received on a smooth white surface we know that the prominences
and the corona would not be visible. And again, if the part of such
a surface on which the image of the sun itself fell were exactly
removed, we know (the experiment has been tried by Airy) that the
prominences would not be seen on the ring of white surface left after
such excision. Still less, then, would the much fainter image of the
corona be seen. But if this ring of white surface, illuminated in
reality by the sky, by the ring of prominences and sierra, and by
the corona, were examined through a battery of prisms (used without
a slit) adjusted to any one of the known prominence tints, the ring
of prominences and sierra would be seen in that special tint. If the
battery of prisms were sufficiently effective, and the tint were one of
the hydrogen tints--preferably, perhaps, the red--we might possibly be
able to trace the faint image of the corona in that tint. But we should
have a better chance with the green tint corresponding to the spectral
line 1474 Kirchhoff. If the ring of white surface were replaced by a
ring of green surface, the tint being as nearly that of 1474 Kirchhoff
as possible, the chance of seeing the coronal ring in that tint would
be somewhat increased; and, still further, perhaps, if the field of
view were examined through green glass of the same tint. It seems just
possible that if prisms of triple height were used, through which the
rays were carried three times, by an obvious modification of the usual
arrangement for altering the level of the rays, thus giving a power of
eighteen flint glass prisms of sixty degrees each, evidence, though
slight perhaps, might be obtained of the presence of the substance
which produces the green line. Thus variations in the condition of
the corona might be recognised, and any law affecting such variations
might be detected. I must confess, however, that a consideration of
the optical relations involved in the problem leads me to regard the
attempt to recognise any traces of the corona when the sun is not
eclipsed as almost hopeless.
It is clear that until some method for thus observing the corona has
been devised, future eclipse observations will acquire a new interest
from the light which they may throw on the coronal variations, and
their possible association in some way, not as yet detected, with the
sun-spot period. Even when a method has been devised for observing the
gaseous corona, the corona whose light comes either directly or by
reflection from solid or liquid matter will still remain undiscernible
save only during total eclipses of the sun. Many years must doubtless
pass, then, before the relation of the corona to the prominences and
the sun-spots shall be fully recognised. But there can be no question
that the solution of this problem will be well worth waiting for, even
though it should not lead up (as it most probably will) to the solution
of the mystery of the periodic changes which affect the surface of the
sun.
FOOTNOTES:
[Footnote 1: The actual condition of the sun in 1842 may be inferred
from the following table, showing the number of spots observed in 1837
the preceding year of maximum disturbance, in 1842, and in 1844 the
following year of minimum disturbance; the observer was Schwabe of
Dessau:
Days of Days without New groups
observation spots observed
1837 168 0 333
1842 307 64 68
1844 321 111 52
Only it should be noticed that nearly all the spots seen in the year
1844 belonged to the next period, the time of actual minimum occurring
early in 1844.]
[Footnote 2: The following table shows the position occupied by the
years 1851 and 1860 in this report, as compared with the year 1848
(maximum next preceding 1851), 1856 (minimum next following 1851) and
1867, minimum next following 1860:--
Days of Days without New groups
observation spots observed
1848 278 0 930
1851 308 0 141
1856 321 193 34
1860 332 0 211
1867 312 195 25
A comparison of the three tables given in these notes and the text will
afford some idea of the irregularities existing in the various waves of
sun-spots.]
_SUN-SPOTS AND COMMERCIAL PANICS._
We are not only, it would seem, to regard the sun as the ultimate
source of all forms of terrestrial energy, existent or potential, but
as regulating in a much more special manner the progress of mundane
events. Many years have passed since Sabine, Wolf, and Gauthier
asserted that variations in the daily oscillations of the magnetic
needle appear to synchronise with the changes taking place in the
sun's condition, the oscillations attaining their _maximum_ average
range in years when the sun shows most spots, and their _minimum_
range when there are fewest spots. And although it is well known that
the Astronomer Royal in England and the President of the Academy
of Sciences in France reject this doctrine, it still remains in
vogue. True, the average magnetic period appears to be about 10.45
years, while Wolf obtains for the sun-spot period 11.11 years; but
believers in the connection between terrestrial magnetic disturbances
and sun-spots consider that among the imperfect records of the past
condition of the sun Wolf must have lost sight of one particular wave
of sun-spots, so to speak. If there have been 24 such waves between
1611 and 1877, when sun-spots were fewest, we get Wolf's period
of 11.11 years; if there have been 25 such waves then, taking an
admissible estimate for the earliest epoch, we get 10.45 years, the
period required to synchronise with the period of terrestrial magnetic
changes. The matter must be regarded as still _sub judice_. This,
however, is only one relation out of many now suggested. Displays of
the aurora, being unquestionably dependent on the magnetic condition
of the earth, would of course be associated with the sun spot period,
if the magnetic period is so; and certainly the most remarkable
displays of the aurora in recent times have occurred when the sun has
shown many spots. Yet this of itself proves nothing more than had
been already known--namely, that the last few magnetic periods have
nearly synchronised with the last few sun-spot periods. It is rather
strange, too, that no auroras are mentioned in the English records
for 80 years preceding the aurora of 1716, and in the records of the
Paris Academy of Sciences one only--that of 1666, which occurred when
sun-spots were fewest. The great aurora of 1723, seen as far south
as Bologna, also occurred at the time of _minimum_ solar activity.
Here we are not depending on either Wolf's period of 11 years or
Brown's of 10-1/2 years; from records of actual observation it is
known that in 1666 and 1713 there were no sun-spots. In fact it is
worth mentioning that Cassini, writing in 1671, says, 'It is now about
20 years since astronomers have seen any considerable spots on the
sun,' a circumstance which throws grave doubt on the law of sun-spot
periodicity itself. It is at least certain that the interval from
_maximum_, spot-frequency to _maximum_, or from _minimum_ to _minimum_,
has sometimes fallen far short of 9 years, and has at others exceeded
18 years.
It appears again that certain meteorological phenomena show a tendency,
more or less marked, to run through a ten-year cycle. Thus, from the
records of rainfall kept at Oxford it appears that more rain fell under
west and south-west winds when sun-spots were largest and most numerous
than under south and south-east winds, these last being the more rainy
winds when sun-spots were least in size and fewest in number. This
is a somewhat recondite relation, and at least proves that earnest
search has been made for such cyclic relations as we are considering.
But this is not all. When other records were examined, the striking
circumstance was discovered that elsewhere, as at St. Petersburg, the
state of things observed at Oxford was precisely reversed. At some
intermediate point between Oxford and St. Petersburg, no doubt the
rainfall under the winds named was equally distributed throughout the
spot period. Moreover, as the conditions thus differ at different
places, we may assume that they differ also at different times. Such
relations appear then to be not only recondite, but complicated.
When we learn that during nearly two entire sun-spot periods cyclones
have been somewhat more numerous in the Indian Seas when spots are
most numerous than when the sun is without spots, and _vice versâ_,
we recognise the possible existence of cyclic relations better worth
knowing than those heretofore mentioned. The evidence is not absolutely
decisive; some, indeed, regard it as scarcely trustworthy. Yet there
does seem to have been an excess of cyclonic disturbance during the
last two periods of great solar disturbance, precisely as there was
also an excess of magnetic disturbance during those periods. The
excess was scarcely sufficient, however, to justify the rather daring
statement made by one observer, that 'the whole question of cyclones
is merely a question of solar activity.' We had records of some very
remarkable cyclonic disturbances during the years 1876 and 1877, when
the sun showed very few spots, the actual _minimum_ of disturbance
having probably been reached late in 1877. A prediction that 1877 would
be a year of few and slight storms would have proved disastrous if
implicit reliance had been placed on it by seamen and travellers.
Rainfall and atmospheric pressure in India have been found to vary
in a cyclic manner, of late years at any rate, the periods being
generally about 10 or 11 years. The activity of the sun, as shown by
the existence of many spots, apparently makes more rainfall at Madras,
Najpore, and some other places; while at Calcutta, Bombay, Mysore,
and elsewhere it produces a contrary effect. Yet these effects are
produced in a somewhat capricious way: for sometimes the year of actual
_maximum_ spot frequency is one in which rainfall is below the average
(instead of above) at the former stations, and above the average
(instead of below) at the latter. It is only by taking averages--and in
a somewhat artificial manner--that the relation seems to be indicated
on which stress has been laid.
Since Indian famines are directly dependent on defective rainfall, it
is natural that during the years over which observation has hitherto
extended the connection apparently existing between sun-spots and
Indian rainfall should seem also to extend itself to Indian famines. It
was equally to be expected that since cyclones have been rather more
numerous, for some time past, in years when sun-spots have been most
numerous, shipwrecks should also have been somewhat more frequent in
such years. Two years ago Mr. Jeula gave some evidence which, in his
opinion, indicated such a connection between sun-spots and shipwrecks.
He showed that in the four years of fewest spots the mean percentage
of losses was 8.64; in four intermediate years the mean percentage was
9.21; in three remaining years of the eleven-year cycle--that is, in
three years of greatest spot frequency the mean percentage was 9.53.
Some suggested that possibly such events as the American war, which
included two of the three years of greatest spot frequency, may have
had more effect than sun-spots in increasing the percentage of ships
lost; while perhaps, the depression following the commercial panic of
1866 (at a time of fewest sun-spots) may have been almost as effective
in reducing the percentage of losses as the diminished area of solar
maculation. But others consider that we ought rather to regard the
American war as yet another product of the sun's increased activity in
1860-61, and the great commercial panic of 1866 as directly resulting
from diminished sun-spots at that time, thus obtaining fresh evidence
of the sun's specific influence on terrestrial phenomena instead of
explaining away the evidence derived from Lloyd's list of losses.
This leads us to the last, and, in some respects, the most singular
suggestion respecting solar influence on mundane events--the idea,
namely, that commercial crises synchronise with the sun-spot period,
occurring near the time when spots are least in size and fewest in
number; or, as Professor Jevons (to whom the definite enunciation of
this theory is due) poetically presents the matter, that from 'the sun,
which is truly "of this great world both eye and soul," we derive our
strength and our weakness, our success and our failure, our elation in
commercial mania, and our despondency and ruin in commercial collapse.'
We have better opportunities of dealing with this theory than with the
others, for we have records of commercial matters extending as far back
as the beginning of the eighteenth century. In fact, we have better
evidence than Professor Jevons seems to have supposed, for whereas in
his discussion of the matter he considers only the probable average
of the sun-spot period, we know approximately the epochs themselves
at which the _maxima_ and _minima_ of sun spots have occurred since
the year 1700. The evidence as presented by Professor Jevons is very
striking, though when examined in detail it is rather disappointing.
He presents the whole series of decennial crises as follows:--1701?
(such query marks are his own), 1711, 1721, 1731-32, 1742 (?), 1752
(?), 1763, 1772-73, 1783, 1793, 1804-5 (?), 1815, 1825, 1836-9 (1837
in the United States), 1847, 1857, 1866 and 1878. The average interval
comes out 10.466 years, showing, as Jevons points out, 'almost perfect
coincidence with Brown's estimate of the average sun-spot period.' Let
us see, however, whether these dates correspond so closely with the
years of _minimum_ spot-frequency as to remove all doubt. Taking 5-1/4
years as the average interval between _maximum_ and _minimum_ sun-spot
frequency, we should like to find every crisis occurring within a year
or so on either side of the _minimum_ though we should prefer perhaps
to find the crisis always following the time of fewest sun-spots,
as this would more directly show the depressing effect of a spotless
sun. No crisis ought to occur within a year or so of _maximum_ solar
disturbance; for that, it should seem, would be fatal to the suggested
theory. Taking the commercial crises in order, and comparing them with
the known (or approximately known) epochs of _maximum_ and _minimum_
spot frequency, we obtain the following results (we italicize numbers
or results unfavourable to the theory):--The doubtful crisis of 1701
followed a spot _minimum_ by _three_ years; the crisis of 1711 preceded
a _minimum_ by one year; that of 1721 preceded a _minimum_ by two
years; 1731-32, preceded a _minimum_ by one year; 1742 preceded a
_minimum_ by _three_ years; 1752 followed a _maximum_ by _two_ years;
1763 followed a _maximum_ by _a year and a half_; 1772-73 came _midway_
between a _maximum_ and a _minimum_; 1783 preceded a _minimum_ by
nearly two years; 1793 came nearly midway between a _maximum_ and a
_minimum_; 1804-5 coincided with a _maximum_; 1815 preceded a _maximum_
by two years; 1825 followed a _minimum_ by _two_ years; 1836-39
_included_ the year 1837 of _maximum_ solar activity (that year being
the time also when a commercial crisis occurred in the United States);
1847 preceded a _maximum_ by a _year and a half_; 1866 preceded a
_minimum_ by a year; and 1878 followed a _minimum_ by a year. Four
favourable cases out of 17 can hardly be considered convincing. If we
include cases lying within two years of a _minimum_, the favourable
cases mount up to seven, leaving ten unfavourable ones. It must be
remembered, too, that a single decidedly unfavourable case (as 1804,
1815, 1837) does more to disprove such a theory than 20 favourable
cases would do towards establishing it. The American panic of 1873,
by the way, which occurred when spots were very numerous, decidedly
impairs the evidence derived from the crises of 1866 and 1878.
_NEW PLANETS NEAR THE SUN._
Perhaps no scientific achievement during the present century has been
deemed more marvellous than the discovery of the outermost member (so
far as is known) of the sun's family of planets. In many respects,
apart from the great difficulty of the mathematical problem involved,
the discovery appealed strongly to the imagination. A planet seventeen
hundred millions of miles from the sun had been discovered in March,
1781, by a mere accident, though the accident was not one likely to
occur to any one but an astronomer constantly studying the star-depths.
Engaged in such observation, but with no idea of enlarging the known
domain of the sun, Sir W. Herschel perceived the distant planet Uranus.
His experienced eye at once recognised the fact that the stranger
was not a fixed star. He judged it to be a comet. It was not until
several weeks had elapsed that the newly discovered body was proved
to be a planet, travelling nearly twice as far away from the sun as
Saturn, the remotest planet before known. A century only had elapsed
since the theory of gravitation had been established. Yet it was at
once perceived how greatly this theory had increased the power of the
astronomer to deal with planetary motions. Before a year had passed
more was known about the motions of Uranus than had been learned about
the motion of any of the old planets during the two thousand years
preceding the time of Copernicus. It was possible to calculate in
advance the position of the newly discovered planet, to calculate
retrogressively the path along which it had been travelling, unseen
and unsuspected, during the century preceding its discovery. And now
observations which many might have judged to be of little value, came
in most usefully. Astronomers since the discovery of the telescope had
formed catalogues of the places of many hundreds of stars invisible to
the naked eye. Search among the observations by which such catalogues
had been formed, revealed the fact that Uranus had been seen and
catalogued as a fixed star twenty-one several times! Flamsteed had seen
it five times, each time recording it as a star of the sixth magnitude,
so that five of Flamsteed's stars had to be cancelled from his lists.
Lemonnier had actually seen Uranus twelve times, and only escaped the
honour of discovering the planet (as such) through the most marvellous
carelessness, his astronomical papers being, as Arago said, 'a very
picture of chaos.' Bradley saw Uranus three times.[3] Mayer saw the
planet once only.
It was from the study of the movements of Uranus as thus seen, combined
with the planet's progress after its discovery, that mathematicians
first began to suspect the existence of some unknown disturbing body.
The observations preceding the discovery of the planet range over an
interval of ninety years and a few months, the earliest observation
used being one made by Flamsteed on December 23, 1690. There is
something very strange in the thought that science was able thus to
deal with the motions of a planet for nearly a century before the
planet was known. Astronomy calculated in the first place where the
planet had been during that time; and then, from records made by
departed observers, who had had no suspicion of the real nature of the
body they were observing, Astronomy corrected her calculations, and
deduced more rigorously the true nature of the new planet's motions.
But still stranger and more impressive is the thought that from
researches such as these, Astronomy should be able to infer the
existence of a planet a thousand million miles further away than Uranus
itself. How amazing it would have seemed to Flamsteed, for example, if
on that winter evening in 1693, when he first observed Uranus, he had
been told that the orb which he was entering in his lists as a star of
the sixth magnitude was not a star at all, and that the observation he
was then making would help astronomers a century and a half later to
discover an orb a hundred times larger than the earth, and travelling
thirty times farther away from the sun.
Even more surprising, however, than any of the incidents which preceded
the discovery of Neptune was this achievement itself. That a planet so
remote as to be quite invisible to the naked eye, never approaching
our own earth within less than twenty-six hundred millions of miles,
never even approaching Uranus within less than nine hundred and fifty
millions of miles, should be detected by means of those particular
perturbations (among many others) which it produced upon a planet not
yet known for three-quarters of a century, seemed indeed surprising.
Yet even this was not all. As if to turn a wonderful achievement into
a miracle of combined skill and good fortune, came the announcement
that, after all, the planet discovered in the spot to which Adams
and Leverrier pointed was not the planet of their calculations, but
travelled in an orbit four or five hundred millions of miles nearer to
the sun than the orbit which had been assigned to the unknown body.
Many were led to suppose that nothing but a most marvellous accident
had rewarded with such singular success the calculations of Adams
and Leverrier. Others were even more surprised to learn that the new
planet departed strangely from the law of distances which all the other
planets of the solar system seemed to obey. For according to that law
(called Bode's law) the distance of Neptune, instead of being about
thirty times, should have been thirty-nine times the earth's distance
from the sun.
In some respects the discovery of a planet nearer to the sun than
Mercury may seem to many far inferior in interest to the detection of
the remote giant Neptune. Between Mercury and the sun there intervenes
a mean distance of only thirty-six millions of miles, a distance
seeming quite insignificant beside those which have been dealt with
in describing the discovery of Uranus and Neptune. Again it is quite
certain that any planet between Mercury and the sun must be far
inferior to our own earth in size and mass, whereas Neptune exceeds
the earth 105 times in size and 17 times in mass. Thus a much smaller
region has to be searched over for a much smaller body. Moreover,
while mathematical calculation cannot deal nearly so exactly with an
intra-Mercurial planet as with Neptune, for there are no perturbations
of Mercury which give the slightest information as to the orbital
position of his disturber, the part of the heavens occupied by the
intra-Mercurial planet is known without calculation, seeing that the
planet must always lie within six or seven degrees or so of the sun,
and can never be very far from the ecliptic.
Yet in reality the detection of an intra-Mercurial planet is a problem
of far greater difficulty than that of such a planet as Neptune, while
even now when most astronomers consider that an intra-Mercurial planet
has been detected, the determination of its orbit is a problem which
seems to present almost insuperable difficulties.
I may remark, indeed, with regard to Neptune, that he might have been
successfully searched for without a hundredth part of the labour and
thought actually devoted to his detection. It may sound rather daring
to assert that any fairly good geometrician could have pointed after
less than an hour's calculation, based on the facts known respecting
Uranus in 1842, to a region within which the disturbing planet must
certainly lie,--a region larger considerably no doubt than that to
which Adams and Leverrier pointed, yet a region which a single observer
could have swept over adequately in half-a-dozen favourable evenings,
two such surveys sufficing to discover the disturbing planet. I
believe, however, that no one who examines the evidence will deny
the accuracy of this statement. It was manifest, from the nature of
the perturbations experienced by Uranus, that between 1820 and 1825
Uranus and the unknown body had been in conjunction. From this it
followed that the disturber must be behind Uranus in 1840-1845 by about
one-eighth of a revolution round the sun. With the assumptions made
by Adams and Leverrier, indeed, the position of the stranger in this
respect could have been more closely determined. There could be little
doubt that the disturbing planet must be near the ecliptic. It followed
that the planet must lie somewhere on a strip of the heavens, certainly
not more than ten degrees long and about three degrees broad, but the
probable position of the planet would be indicated as within a strip
four degrees long and two broad.[4] Such a strip could be searched over
effectually in the time I have named above, and the planet would have
been found in it. The larger region (ten degrees long and three broad)
could have been searched over in the same time by two observers. If
indeed the single observer used a telescope powerful enough to detect
the difference of aspect between the disc of Neptune and the point-like
image of a star (the feature by which Galle, it will be remembered,
recognised Neptune), a single night would have sufficed for the search
over the smaller of the above-mentioned regions, and two nights for the
search over the larger. The search over the smaller, as already stated,
would have revealed the disturbing planet.
On the other hand, the astronomer could not determine the direction of
an intra-Mercurial planet within a considerably larger space on the
heavens, while the search over the space within which such a planet was
to be looked for was attended by far more serious difficulties than the
search for Neptune. In fact, it seems as though, even when astronomers
have learned where to look for such a planet, they cannot expect to see
it under ordinary atmospheric conditions when the sun is not eclipsed.
Let us consider the history of the search for an intra-Mercurial planet
from the time when first the idea was suggested that such a planet
exists until the time of its actual discovery--for so it seems we must
regard the observations made during the total eclipse of July, 1878.
On January 2, 1860, M. Leverrier announced, in a paper addressed to
the Academy of Sciences, that the observations of Mercury could not
be reconciled with the received elements of the planet. According to
those elements, the point of Mercury's orbit which lies nearest to the
sun undergoes a certain motion which would carry it entirely round in
about 230,000 years. But to account for the observed motions of Mercury
as determined from twenty-one transits over the sun between the years
1697 and 1848, a slight increase in this motion of the perihelion was
required, an increase, in fact, from 581 seconds of arc in a century
to nearly 585. The result would involve, he showed, an increase in
our estimate of the mass of Venus by a full tenth. But such a change
would necessarily lead to difficulties in other directions; for the
mass of Venus had been determined from observations of changes in the
position of the earth's path, and these changes had been too carefully
determined to be readily regarded as erroneous. 'This result naturally
filled me with inquietude,' said Leverrier later. 'Had I not allowed
some error in the theory to escape me? New researches, in which every
circumstance was taken into account by different methods, ended only in
the conclusion that the theory was correct, but that it did not agree
with the observations.' At last, after long and careful investigation
of the matter, he found that a certain slight change would bring
observation and theory into agreement. All that was necessary was
to assume that matter as yet undiscovered exists in the sun's
neighbourhood. 'Does it consist,' he asked, 'of one or more planets, or
other more minute asteroids, or only of cosmical dust? The theory tells
us nothing on this point.'
Leverrier pointed out that a planet half the size of Mercury between
Mercury and the sun would account for the discrepancy between
observation and theory. But a planet of that size would be a very
conspicuous object at certain times, even when the sun was not
eclipsed; and when favourably placed during eclipses would be a
resplendent orb which would attract the notice of even the most
careless observer. For we must remember that the brightness of a
planet depends in part on its size and its distance from the earth,
and in part on its distance from the sun. A planet half as large as
Mercury would have a diameter about four-fifths of Mercury's, and at
equal distance would present a disc about two-thirds of Mercury's in
apparent size. But supposing the planet to be half as far from the sun
as Mercury (and theory required that the planet should be rather nearer
the sun), its surface would be illuminated four times as brightly as
that of Mercury. Hence, with a disc two-thirds as large as Mercury's,
but illuminated four times as brightly, the planet would shine
nearly three times as brilliantly when seen under equally favourable
conditions during eclipse. In such an inquiry, the mean distance of the
two bodies need not be specially considered. Each planet would be seen
most favourably when in the part of its path remotest from the earth,
so that the planet nearest to the sun would on the whole have the
advantage of any difference due to that cause. For, of course, while
Mercury, being farther from the sun, approaches the earth nearer when
between the earth and sun, he recedes farther from the sun for the same
reason when on the part of his path beyond the sun.
It was perfectly clear that no such planet as Leverrier considered
necessary to reconcile theory and observation exists between the sun
and Mercury's orbit. It appeared necessary, therefore, to assume that
either there must be several smaller planets, or else that a cloud of
cosmical dust surrounds the sun. Now it is to be noticed that in either
case the entire mass of matter between Mercury and the sun must be
greater to produce the observed disturbance than the mass of a single
planet travelling at the outside of the region supposed to be occupied
either by a group of planets or a cloud of meteorites.
Leverrier considered the existence of a ring of small planets afforded
the most probable explanation. He recommended astronomers to search
for such bodies. It is noteworthy that it was in reference to this
suggestion that M. Faye (following a suggestion of Sir J. Herschel's)
proposed that at several observatories, suitably selected, the sun
should be photographed several times every day with a powerful
telescope. 'I have myself,' he says, 'shown how to give these
photographs the value of an astronomical observation by taking two
impressions on the same plate after an interval of two minutes. It will
be sufficient to superpose the transparent negatives of this size taken
at a quarter of an hour's interval, to distinguish immediately the
movable projection of a small planet in the middle of the most complex
groups of small spots.'
It was while Leverrier and Faye were discussing this matter, that news
came of the recognition of an intra-Mercurial planet by Lescarbault,
a doctor residing at Orgères, in the department of Eure et Loire. The
story has been so often told that I am loth to occupy space with it
here. An account is given of the leading incidents in an article called
'The Planets put in Leverrier's Balance,' in my 'Science Byways,'
and a somewhat more detailed narrative in my 'Myths and Marvels of
Astronomy.' Here, it will suffice to give a very slight sketch of this
interesting episode in the history of astronomy.
On January 2, 1860, news reached Leverrier that Lescarbault had on
March 26, 1859, seen a round black spot on the sun's face, and had
watched it travelling across like a planet in transit. It had remained
in view for one hour and a quarter. Leverrier could not understand why
three-quarters of a year had been allowed to elapse before so important
an observation had been published. He went to Orgères with the idea
of exposing a pretender. The interview was a strange one. Leverrier
was stern and, to say the truth, exceedingly rude in his demeanour,
Lescarbault singularly lamb-like. If our chief official astronomer
called uninvited upon some country gentleman who had announced an
astronomical discovery, and behaved as Leverrier did to Lescarbault,
there would most certainly have been trouble; but Lescarbault seems
to have been rather pleased than otherwise. 'So you are the man,'
said Leverrier, looking fiercely at the doctor, 'who pretends to have
seen an intra-Mercurial planet. You have committed a grave offence in
hiding your observation, supposing you really have made it, for nine
months. You are either dishonest or deceived. Tell me at once and
without equivocation what you have seen.' Lescarbault described his
observation. Leverrier asked for his chronometer, and, hearing that
the doctor used only his watch, the companion of his professional
journeys, asked how he could pretend to estimate seconds with an old
watch. Lescarbault showed a silk pendulum 'beating seconds,'--though it
would have been more correct to say 'swinging seconds.' Leverrier then
examined the doctor's telescope, and presently asked for the record
of the observations. Lescarbault produced it, written on a piece of
laudanum-stained paper which at the moment was doing service as a
marker in the _Connaissance des Temps_. Leverrier asked Lescarbault
what distance he had deduced for the new planet. The doctor replied
that he had been unable to deduce any, not being a mathematician: he
had made many attempts, however.[5] Hearing this, Leverrier asked for
the rough draft of these ineffective calculations. 'My rough draft?'
said the doctor. 'Paper is rather scarce with us here. I am a joiner as
well as an astronomer' (we can imagine the expression of Leverrier's
face at this moment); 'I calculate in my workshop, and I write upon the
boards; and when I wish to use them in new calculations, I remove the
old ones by planing.' On adjourning to the carpenter's shop, however,
they found the board with its lines and its numbers in chalk still
unobliterated.
This last piece of evidence, though convincing Leverrier that
Lescarbault was no mathematician, and therefore probably in his eyes
no astronomer, yet satisfied him as to the good faith of the doctor of
Orgères. With a grace and dignity full of kindness, which must have
afforded a singular contrast to his previous manner, he congratulated
Lescarbault on his important discovery. He made some inquiry also at
Orgères, concerning the private character of Lescarbault, and learning
from the village _curé_, the _juge de paix_, and other functionaries,
that he was a skilful physician, he determined to secure some reward
for his labours. At Leverrier's request M. Rouland, the Minister
of Public Instruction, communicated to Napoleon III. the result of
Leverrier's visit, and on January 25 the Emperor bestowed on the
village doctor the decoration of the Legion of Honour.
To return to astronomical facts.
It appears from Lescarbault's observation, that on March 26, 1859, at
about four in the afternoon, a round black spot entered on the sun's
disc. It had a diameter less than one-fourth that of Mercury (which he
had seen in transit with the same telescope and the same magnifying
power on May 8, 1845). The time occupied in the transit of this spot
was about one hour seventeen minutes, and, the chord of transit
being somewhat more than a quarter of the sun's diameter in length,
Lescarbault calculated that the time necessary to describe the sun's
diameter would have been nearly four and a half hours. The inclination
of the body's path to the ecliptic seemed to be rather more than 6
degrees, and was probably comprised between 5-1/3 and 7-1/3 degrees.
From Leverrier's calculations, it appeared that the time of revolution
of the new planet would be 19 days 17 hours, its distance from the
sun about 147, the earth's being taken as 1,000; giving for Mars,
the earth, Venus, Mercury, and Vulcan (as the new planet was named),
the respective distances 1, 524, 1,000, 723, 387, and 147. Leverrier
assigned 12-1/5 degrees as Vulcan's inclination, and the places
where it crosses the ecliptic he considered to be in line with those
occupied by the earth on or about April 3 and October 6. Judging from
Lescarbault's statement respecting the apparent size of the dark spot,
Leverrier concluded that the volume of the stranger must be about
one-seventeenth of Mercury's, the masses being presumably in the same
proportion. Hence he inferred that the new planet would be quite
incompetent to produce the observed change in the orbit of Mercury.
Leverrier further found that the brilliancy of Vulcan when the planet
was furthest from the sun on the sky (about eight degrees) would be
less than that of Mercury when similarly placed in his orbit, and he
hence inferred that Vulcan might readily remain unseen, even during
total eclipse. Here, as it seems to me, Leverrier's reasoning was
erroneous. If Vulcan really has a volume equal to one-seventeenth
of Mercury's, the diameter of Vulcan would be rather less than two
fifths of Mercury's and the disc of Vulcan at the same distance about
two-thirteenths of Mercury's. But Vulcan, being nearer the sun than
Mercury in the ratio of 147 to 387, or say 15 to 39, would be more
brightly illuminated in the ratio of 39 times 39 to 15 times 15, or
nearly as 20 to 3. Hence if we first diminish Mercury's lustre when
at his greatest apparent distance from the sun in the ratio of 2 to
13, and increase the result in the ratio of 20 to 3, we get Vulcan's
lustre when he is at his greatest apparent distance from the sun. The
result is that his lustre should exceed Mercury's in the same degree
that 40 exceeds 39. Or practically, for all the numbers used have been
mere approximations, the inference is that Vulcan and Mercury, if both
seen when at their greatest distance from the sun during eclipse, would
probably shine with equal lustre. But in that case Vulcan would be a
very conspicuous object indeed, at such a time; for Mercury when at his
greatest distance from the sun, or greatest elongation, is a bright
star even on a strongly illuminated twilight sky; moreover, Vulcan,
when at either of his greatest elongations, ought to be visible in full
daylight in a suitably adjusted telescope. For Mercury is well seen
when similarly placed, and even when much nearer to the sun and on the
nearer part of his path where he turns much more of his darkened than
of his illuminated hemisphere towards us. Venus has been seen when
so near the sun that the illuminated portion of her disc is a mere
thread-like sickle of light. Nay, Professor Lyman, of Yale College, in
America, has seen her when so near the sun that she appeared to be a
mere circular thread of light, the completion of the circle being the
best possible proof how exceedingly fine the thread must have been, and
also how small its intrinsic lustre.
This is indeed the chief difficulty in Lescarbault's supposed
observation. If he really saw a body in transit across the sun, moving
at the observed rate, and having anything like the observed diameter,
that body ought to have been seen repeatedly during total eclipses of
the sun, and ought not to have escaped the search which has been made
over and over again near the sun for intra-Mercurial planets. Either we
must reject Lescarbault's narrative absolutely, or we must suppose that
he greatly over-estimated the size of the body he observed.
Another difficulty almost equally important is found to exist when
we consider the circumstances of Lescarbault's supposed discovery.
Suppose the path of Vulcan to be inclined about twelve degrees or
thereabouts to the ecliptic or to the plane in which the earth travels.
Then, as seen from the earth on April 3, and October 6, this path, if
it were a material ring, would appear as a straight line across the
sun's centre, and extending on either side of the sun to a distance
of about 16 sun-breadths. As seen on January 3 and July 5, when it
would have its greatest opening, Vulcan's path would appear as an oval
whose longest axis would be about 32 sun-breadths, while its shortest
would be little more than 6 sun-breadths, the sun of course occupying
the centre of the ellipse, which, where closest to him, would lie
but about 2-1/2 sun-breadths only from the outline of his disc. Now
it is easily seen that the path of Vulcan, changing in this way from
apparent straightness to a long oval (whose breadth is about one-fifth
its length), back to straightness but differently inclined, then to
the same oval as before but opened out the other way, and so back to
its original straightness and inclination, must, for no inconsiderable
portion of the year on either side of April 3 and October 6, intersect
the outline of the sun's disc. From a rough but sufficiently accurate
calculation which I have made, I find that the interval would last
about 36 days at each season, that is, from about March 16 to April 21
in spring, and from about September 18 to about October 24 in autumn.
But during a period of 36 days there would generally be two passages of
Vulcan between the earth and sun, and there would always be one (in any
long period of time two such passages would be five times as common an
event during one of these intervals as a single passage). Consequently
there would be at least two transits of Vulcan every year, and there
would generally be four transits; the average number of transits would
be about eleven in three years. With a wider orbit and a greater
inclination transits would be fewer; but even with the widest orbit and
the greatest inclination that can possibly be allowed, there would be
at least one transit a year on the average.
Now when we remember that, so far as the northern hemisphere is
concerned, the sun is observed on every fine day in almost every
country in Europe and in half the States of the American Union, to
say nothing of observations in Asia, where England and Russia have
several observatories, while in the southern hemisphere there are
many observatories, in Australia, South Africa, and South America (on
both side of the Andes), we see how exceedingly small must be the
chance that Vulcan could escape detection even for a single year.
Far less could Vulcan have escaped all the years which have elapsed
since Lescarbault announced his discovery, to say nothing of all the
observations made by Carrington, Schwabe, and many others, before the
year 1860. If Vulcan really exists, and really has the dimensions and
motions described by Lescarbault, the planet must long ere this have
been repeatedly seen upon the sun's disc by experienced observers.
As a matter of fact, Wolf has collected nineteen observations of dark
bodies unlike spots on the sun, during the interval between 1761 and
1865. But as Professor Newcomb justly points out, with two or three
exceptions, the observers are almost unknown as astronomers. In one
case at least the object seen was certainly not a planet, since
it was described as a cloud-like appearance. 'On the other hand,'
says Newcomb, 'for fifty years past the sun has been constantly and
assiduously observed by such men as Schwabe, Carrington, Secchi, and
Spörer, none of whom have ever recorded anything of the sort. That
planets in such numbers should pass over the solar disc, and be seen by
amateur astronomers, and yet escape all these skilled astronomers, is
beyond all moral probability.'
It must be remembered that an inexperienced observer of the sun might
readily mistake a spot of unusual roundness and darkness for a planet's
disc. The practised observer would perceive peculiarities at once
indicating the object as a spot on the sun; but these peculiarities
would escape the notice of a beginner, or of one using a telescope of
small power. Again, an inexperienced observer is apt to mistake the
change of position which a spot on the sun undergoes on account of the
diurnal motion, for a change of place on the sun's disc. At noon, for
instance, the uppermost point of the sun's disc is the north point;
but in the afternoon the uppermost point is east of the true north
point. Thus a spot which at noon was a short distance below the highest
point of the sun's disc would at two or three be considerably to the
west of the highest point, though it had undergone in the interval no
appreciable change of position on the solar disc. Suppose now that
at two or three in the afternoon clouds come over the sun's face,
and he is not seen again that day. On the morrow the spot may have
disappeared, as solar spots are apt enough to do. The observer, then
(assuming him to be inexperienced like most of those who have described
such spots), would say, I saw at noon a small round spot which in the
course of the next three hours moved over an appreciable arc towards
the west (the right direction, be it remembered, for a planet to cross
the sun's face). An experienced observer would not make such a mistake.
But let one point be carefully noted. An experienced astronomer would
be very apt to forget that such a mistake could be made. He would take
it for granted that the observer who described such a change in a
spot's position meant a real change, not a change due to the diurnal
motion.
Therefore, although Leverrier, Moigno, Hind, and other men of science,
have adopted Lescarbault's account, I hold it to be absolutely certain
that that account is in some respect or other erroneous. Newcomb goes
even farther. He says, it is very certain that if the disturbance of
Mercury is due to a group of planets, 'they are each so small as to be
invisible in transits across the sun. They must also,' he proceeds, 'be
so small as to be invisible during total eclipses of the sun, because
they have always failed to show themselves then.' This remark relates,
of course, to naked-eye vision. As no intra-Mercurial planet had ever
been searched for systematically with the telescope, before the recent
eclipse, there was nothing to prevent astronomers from believing that
a group of planets, visible in the telescope during total eclipse, may
travel between the sun and the path of Mercury.
I proceed at once to consider the evidence afforded during the eclipse
of July, 1878, not discussing further the question of Lescarbault's
Vulcan, because it appears to me so clear that there must have been
some mistake, and because later observations seem to throw clearer
evidence on the matter than any which had been before obtained. Yet it
must be admitted that even now the evidence is not all that could be
desired.
Professor Watson, of Ann Arbor, the discoverer of more than a score of
the small planets which travel between the paths of Mars and Jupiter,
had been searching for an _extra-Neptunian_ planet, when the approach
of the eclipse of July, 1878, suggested the idea that he should return
for a while from those dismal depths which lie beyond the path of
Neptune to seek for a new planet within the glowing region between the
sun and the path of Mercury. The occasion was exceptionally favourable
because of the great height above the sea-level from which the eclipse
could be observed. Accordingly he betook himself to Rawlins, Wyoming,
and prepared for the search by providing his telescope with card
circles in such sort that the place of any observed star could be
recorded by a pencil-mark on these circles, instead of being read off
(with the possibility of error) in the usual way. It is unnecessary
to explain further, because every one who has ever used an equatorial
telescope, or is acquainted with the nature of the instrument, will
at once understand Professor Watson's plan, whereas those unfamiliar
with the instrument, would not gain any insight into the nature of his
plan without much more explanatory matter than could be conveniently
given here, even if any explanation without illustrations could make
the matter clear. Let it suffice to note that, having brought any star
centrally into the telescopic field of view, Professor Watson marked in
pencil where the ends of certain pointers came; and that these marks
served to indicate, after the eclipse was over, the position of the
observed star.
Thus provided, Professor Watson, so soon as totality began, searched
on the eastern side of the sun, and there saw certain stars belonging
to the constellation Cancer, where the sun was situate at the time. He
then examined the western side of the sun, and having swept out to a
star which he took to be Zeta Cancri (though he was rather surprised at
its brightness,--but of that more anon) he returned towards the sun,
encountering on his way a star of the fourth magnitude or rather less,
about two degrees to the west of the sun. Close by was the star Theta
Cancri; but Theta was much fainter, and was seen at the same time a
little further west. It is not easy to understand why Watson did not
make comparison between the position of the new star and Theta, instead
of making comparison between the new star, the sun, and the star which
he took to be Zeta. For a comparison with a known object so close as
Theta would have given more satisfactory evidence than a comparison
with objects farther away. However, as he distinctly states in a letter
to Sir G. Airy that the new star was very much brighter than Theta
Cancri, which was seen a little farther to the west, we cannot doubt
that he had sufficient evidence to prove the new star and Theta Cancri
to be distinct orbs.
He adds that there was no appearance of elongation, as might be
expected if the new object were a comet. It had a perceptible disc,
though the magnifying power was only forty five.
The accompanying figure will serve to give a fair idea of the position
of the stranger.
[Illustration: Fig. 1.--Watson's new Planet.]
Now comes the evidence which was at first supposed to be strongly
corroborative of Watson's observation,--the recognition of a star of
about the fourth magnitude, near Theta Cancri, by Professor Louis
Swift, who observed the eclipse from Pike's Peak, in Colorado.
Professor Swift also made some rather unusual arrangements with his
telescope, but they were not altogether so well adapted to advance his
purpose as were Professor Watson's. To prevent the instrument from
swaying he tied what he calls a pole (but what in England I imagine
would be called a stick), ten feet long, about a foot from the eye-end
of the telescope, leaving the other end of this singular appendage
to trail on the ground. (The telescope was set low, Professor Swift
judging, it would seem, that the most comfortable way to observe was
to lie on his back.) As a natural consequence, while he could move his
telescope very readily one way, trailing the stick along, he could not
move it the other way, because the stick's end immediately stuck into
the ground. As the stick was on the west of the telescope, Professor
Swift could move the eye-end eastwards, following the sun's westwardly
motion. Of course the telescope was to have been released from the
stick when totality began, but unfortunately Professor Swift omitted
to do this, so that he had to work during totality with a hampered
telescope.
The following is his account of what he saw:--
'My hampered telescope behaved badly, and no regularity in the sweeps
could be maintained. Almost at once my eye caught two red stars about
three degrees south-west of the sun, with large round and equally
bright discs which I estimated as of the fifth magnitude, appearing
(this was my thought at the time) about as bright in the telescope
as the pole-star does to the naked eye. I then carefully noted their
distance from the sun and from each other, and the direction in which
they pointed, &c., and recorded them in my memory, where, to my mind's
eye, they are still distinctly visible. I then swept southward, not
daring to venture far to the west, for fear I should be unable to get
back again, and soon came upon two stars resembling in every particular
the former two I had found, and, sighting along the outside of the
tube, was surprised to find I was viewing the same objects. Again I
observed them with the utmost care, and then recommenced my sweeps in
another direction; but I soon had them again, and for the third time,
in the field. This was also the last, as a small cloud hindered a final
leave-taking just before the end of totality, as I had intended. I
saw no other star besides these two, not even Delta, so close to the
eastern edge of the sun.'
He adds that the apparent distance between the two bodies was about
one-fourth the sun's diameter. (These are not his words, but convey the
same meaning.)
Again, he adds that, from three careful estimates, he found the two
stars pointed exactly to the sun's centre. He knew one of the two
bodies was Theta; but unfortunately he could not tell which was Theta
and which the new star or planet. 'But,' he says, 'Professor Watson
happily comes to the rescue, and with his means of measuring finds the
planet nearest to the sun.'
Unhappily, however, Professor Watson does not come absolutely to the
rescue here. On the contrary, to use Professor Swift's words in another
part of his letter (and speaking of another matter), 'it is just here
where the trouble begins.' If we construct a little map illustrating
what Professor Swift describes, we get the accompanying arrangement
(fig. 2). It is clearly quite impossible to reconcile this view of the
supposed new planet with Professor Watson's. If three careful estimates
showed Swift the stranger and Theta situated as in fig. 2, it is
absolutely certain that either Watson's observation was very far from
the truth, or else the strange orb he saw was not the same that Swift
saw. On the other hand, if Watson's observation was trustworthy, it is
certain that either Swift's three estimates were inexact or he saw a
different new body. Again, their accounts of the relative brightness of
Theta and the stranger could not possibly be reconciled if we supposed
they were observing the same new planet, for Watson says distinctly
that the stranger was _very much brighter_ than Theta; while Swift
says, with equal distinctness, that the two stars were _equally bright_.
[Illustration: Fig. 2.--Swift's new Planet?]
If we accept both observations, we must consider that the strange orb
seen by Swift was not the nearer to the sun, but the other, for Watson,
in his letter to Sir G. Airy, says that he saw both Theta and his own
new planet, and he could not have overlooked Swift's new planet, if
placed as in fig. 2, whereas if the star there marked as the stranger
were really Theta, Watson might readily enough have overlooked the
other star, as farther away from his newly-discovered planet. According
to this view, the actual arrangement at the time of the eclipse was as
shown in fig. 3.
[Illustration: Fig. 3.--Suggested explanation of Watson's and Swift's
observations.]
But this is not quite all. Professor Watson saw another body, which
in his opinion was a planet. I have already mentioned that he thought
Zeta remarkably bright. It seemed to him a star of nearly the third
magnitude, whereas Zeta Cancri is only of the fifth. Nay, speaking of
the planet near Theta, and of this star which he took for Zeta, he
says, 'they were probably really brighter [than the 4-1/2 and 3-1/2
magnitude respectively], because the illumination of the sky was not
considered in the estimates.' Before he had thoroughly examined the
pencil marks on his card circles, and made the necessary calculations,
he supposed the brighter star to be Zeta, because he did not see the
latter star. But when he examined his result carefully, he found that
the bright star was set (according to his pencil marks) more than
one degree east of Zeta. Writing on August 22, he says, 'The more I
consider the case the more improbable it seems to me that the second
star which I observed, and thought it might be Zeta, was that known
star. I was not certain, in this case, whether the wind had disturbed
the telescope or not. As it had not done so in the case of any other of
six pointings which I recorded, it seems almost certain that the second
was a new star.' It would be easy to understand why Professor Watson
had not seen Zeta, for he only swept as far as the star he mistook for
Zeta, and, as the accompanying figure shows, Zeta was beyond that star
on the west.[6]
Fig. 4 represents the apparent result of the observations made by
Professors Watson and Swift, if all the observations are regarded
as trustworthy. The six stars shown in the figure were probably the
six referred to in the preceding paragraph. The two unnamed ones are
well-known red stars.
[Illustration: Fig. 4.--Showing all the stars observed by Watson and
Swift.]
Let it be noticed, that we cannot reject planet 1, without rejecting
all Watson's observations. We cannot reject planet 2, without rejecting
all Swift's observations. We cannot set this planet to the left of
Theta without throwing doubt on Watson's observations. If Watson swept
over Theta westward without seeing 2, Swift must have made some mistake
as yet unexplained. As for planet 3, if we admit the possibility
that this object really was Zeta, we must admit also the possibility
that the object marked as planet 1 was really Theta, or rather we
should have to do so, were it not that Watson saw Theta also, and (I
suppose) in the same field of view, since he speaks confidently of the
inferiority of Theta in brightness.
It should further be noticed, that though Swift's and Watson's
observations by no means agree in details, they do in reality support
each other (unless Watson should definitely assert that no star as
bright as Theta existed either to the west or to the east of that star,
at the distance indicated by Swift.) For they agree in indicating the
existence of small planets near the sun, such as can only be seen with
the telescope.
On the other hand, it is to be noted that other observers failed to see
any of these bodies, though they looked specially for intra-Mercurial
planets. Thus Professor Hall, of the Washington Observatory, searched
over a larger space than is included in fig. 4, without seeing any
unknown body. But as he also failed to see many known bodies which
should have been seen, it is probable that the search was too hurried
to be trustworthy.
It would be satisfactory to be able to say that any of the supposed
planets might have been Lescarbault's Vulcan. But in reality, I fear,
this cannot have been the case. In the _Times_, I expressed, in an
article dated August 14, 1878, the opinion that the evidence obtained
establishes the existence of the planet which had so long been regarded
as a myth. That opinion was based on a very careful investigation of
the evidence available at the time. But it does not accord with what
has since been learned respecting Watson's observations.
We may dismiss planet 3 at once. If Watson is right about this body
being distinct from Zeta (a point about which, I must confess, I feel
grave doubts), then this must be a planet travelling in an orbit much
wider than we can possibly assign to Vulcan. For even at the distance
of some seven degrees from the sun it showed no sign of gibbosity. If
it had then been at its greatest elongation it would have appeared only
half-full. But with the power Watson was using, which enabled him to
pronounce that the smaller body near Theta showed no elongation, he
would at once have noticed any such peculiarity of shape. He could not
have failed to observe any gibbosity approaching to that of the moon
when three-quarters full. Moreover on July 29 a planet which has its
points of crossing the ecliptic opposite the earth's place on April
3 and October 6, could not appear where Watson saw this body (fully
two degrees from the ecliptic) unless either its orbit were far wider
than that which Leverrier assigned to Vulcan, or else its inclination
far greater. Neither supposition can be reconciled with Lescarbault's
observation.
With regard to planets 1 and 2, the case is equally strong against the
theory that Vulcan was observed. The same reasoning applies to both
these bodies. When I speak therefore of planet 1, it will be understood
that planet 2 also is dealt with. First, as this planet appeared with
a disc appreciably round, it is clear that it must have been near the
point of its orbit farthest from the earth, that is, the point directly
beyond the sun. It was then nearly at its brightest. Yet it appeared as
a fourth-magnitude star only. We have seen that Lescarbault's Vulcan,
even when only half-full, would appear as bright as Mercury at his
brightest, if Lescarbault's account can be accepted in all its details.
Situated as planet 1 was, Vulcan would have shown much more brightly
than an average first-magnitude star. At a very moderate computation it
would have been twice as bright as such a star. But planet 1 appeared
fainter than a fourth-magnitude star. Assume, however, that in reality
it was shining as brightly as an average third-magnitude star. Then it
shone with much less than a twentieth of the lustre Vulcan should have
had, if Lescarbault's estimate were correct. Its diameter then cannot
be greater than a quarter of that which Leverrier assigned to Vulcan
on the strength of Lescarbault's observation. In fact, the apparent
diameter of planet 1, when in transit over the sun's face, could not be
more than a sixteenth of Mercury's in transit, or about two-fifths of a
second,--roughly, about a 5000th part of the sun's apparent diameter.
It is certain that Lescarbault could not have made so considerable a
mistake as this. Nay, it is certain, that with the telescope he used he
could not have seen a spot of this size at all on the sun's face.
It will be seen that Lescarbault's observation still remains
unconfirmed, or rather, to speak more correctly, the doubts which
have been raised respecting Lescarbault's Vulcan are now more than
ever justified. If such a body as he supposed he saw really travels
round the sun within the orbit of Mercury, it is certain that the
observations made last July by those who were specially engaged in
seeking for Vulcan must have been rewarded by a view of that planet.
In July, Lescarbault's Vulcan could not have been invisible, no matter
in what part of his orbit it might be, and the chances would have been
greatly in favour of its appearing as a very bright star, without
telescopic aid.
But on the other hand it seems extremely probable,--in fact, unless
any one be disposed to question the veracity of the observers, it is
certain,--that within the orbit of Mercury there are several small
planets, of which certainly two, and probably three, were seen during
the eclipse of July 29, 1878. All these bodies must be beyond the
range of any except the most powerful telescopes, whether sought for
as bright bodies outside the sun (not eclipsed) or as dark bodies in
transit across the sun's face. The search for such bodies in transit
would in fact be hopeless with any telescope which would not easily
separate double stars one second of arc apart. It is with large
telescopes, then, and under favourable conditions of atmosphere,
locality, and so forth, that the search for intra-Mercurial planets in
transit must in future be conducted. As the observed disturbance of
Mercury's perihelion, and the absence of any corresponding disturbance
of his nodes (the points where he crosses the plane of the earth's
motion) show that the disturbing bodies must form a ring or disc whose
central plane must nearly coincide with the plane of Mercury's path,
the most favourable time for seeing these bodies in transit would
be the first fortnights in May and November; for the earth crosses
the plane of Mercury's orbit on or about May 8 and November 10. I
believe that a search carried out in April, May, and June, and in
October, November, and December, with the express object of discovering
_very_ small planets in transit, could not fail to be quickly
rewarded,--unless the observations made by Watson and Swift are to be
wholly rejected.
[Since this was written, Professor Swift has expressed the opinion
that his planet cannot possibly have been the one seen near Theta
Cancri by Professor Watson,--who it seems saw Theta in the centre
of a large field of view, and must therefore have seen Swift's
planet had that object been placed either as shown in fig. 2 or
fig. 3. Hence Professor Swift considers that both the stars he
himself saw were planets, and that he did not see Theta at all.
The reasoning in the last five paragraphs of the above essay would
not be in the least affected if we adopted Professor Swift's
conclusion, that four and not three intra-Mercurial planets were
detected during the eclipse of July last. Yet later Professor
Peters of Clinton has indicated reasons for believing that while
Watson simply mistook for planets the two fixed stars, Theta
and Zeta Cancri, Professor Swift saw no planets at all. This
interpretation would account fully, though not very satisfactorily,
for all that is mysterious in the two narratives.]
FOOTNOTES:
[Footnote 3: Two observations of Uranus, by Bradley, were discovered
by the late Mr. Breen, and published in No. 1463 of the _Astronomische
Nachrichten_.]
[Footnote 4: Let the student make the following construction if he
entertains any doubt as to the statements made above. Having traced the
orbits of the earth and Uranus from my chart illustrating the article
'Astronomy' in the _Encyc. Brit._, let him describe a circle nearly
twice as large to represent the orbit of Neptune as Bode's law would
give it. Let him first suppose Neptune in conjunction with Uranus in
1820, mark the place of the earth on any given day in 1842, and the
place of the fictitious Neptune; a line joining these points will
indicate the direction of Neptune on the assumptions made. Let him
next make a similar construction on the assumption that conjunction
took place in 1825. (From the way in which the perturbation of Uranus
reached a maximum between 1820 and 1825, it was practically certain
that the disturber was in conjunction with Uranus between those years.)
These two constructions will give limiting directions for Neptune
as viewed from the earth, on the assumption that his orbit has the
dimensions named. He will find that the lines include an angle of a
few degrees only, and that the direction line of the true Neptune is
included between them.]
[Footnote 5: The problem is in reality, at least in the form in which
Lescarbault attacked it, an exceedingly simple one. A solution of the
general problem is given at p. 181 of my treatise on the _Geometry
of Cycloids_. It is, in fact, almost identical with the problem of
determining the distance of a planet from observations made during a
single night.]
[Footnote 6: It may be necessary, perhaps, to explain to some why the
western side is on the right in the little maps illustrating this
paper, and not, as usual with maps, on the left. We are supposed to
look down towards the earth in the case of a terrestrial map, and to
look up from the earth in the case of a celestial map, and naturally
right and left for the former attitude become respectively left and
right for the latter.]
_RESULTS OF THE BRITISH TRANSIT EXPEDITIONS._
Another noteworthy attempt has been made to estimate the distance which
separates our earth from the mighty central orb round which she travels
with her fellow-worlds the planets. In other words, the solar system
itself has been remeasured; for the measurement of any part of the
system is in fact the measurement of the entire system, the proportions
of which, as distinguished from its actual dimensions, have long been
accurately known.
I propose briefly to describe the results which have been obtained
(after some three years of careful examination) from the observations
made by the British parties sent north, south, east, and west to
observe the transit of Venus on December 9, 1874; and then to consider
how these results compare with those which had before been obtained.
First, however, it may be well to remind the reader of the unfavourable
conditions under which the task of measuring our distance from the
remote sun must of necessity be attacked.
Not unfrequently we hear the measurement of the sun's distance, and
the various errors which astronomers have had to correct during the
progress of their efforts to deal with the problem, referred to in
terms which would imply that astronomy had some reason to be ashamed
of labours which are in reality among the most noteworthy achievements
of their science. Because, some twenty years ago, the estimate of 95
million miles, which had for half a century held its ground in our
books of astronomy as the true distance of the sun, was replaced for a
while by an estimate of about 91-1/2 million miles, which has in turn
been displaced for an estimate of about 92-1/3 million miles, it has
been said that astronomy has very little claim to be called the exact
science. It is even supposed by some that astronomy is altogether
at sea respecting the sun's distance--which, if the estimates of
astronomers thus vary in the course of three-quarters of a century, may
in reality, it is thought, be very different from any of the values
hitherto assigned. Others suppose that possibly the sun's distance may
vary, and that the diminution of three or four million miles in the
estimates adopted by astronomers may correspond to an approach of the
earth towards the sun by that amount, an approach which, if continued
at the same rate, would, before many centuries, bring the earth upon
the surface of the sun, to be consumed as fuel perhaps for the warming
of the outer planets, Mars, Jupiter, and the rest.
All these imaginings are mistaken, however. The exactness of astronomy,
as a science, does not depend on the measurement of the sun's distance
or size, any more than the accuracy of a clock as a timekeeper depends
on the exactness with which the hands of the clock are limited to
certain definite lengths. The skill with which astronomy has dealt with
this particular problem of celestial surveying has been great indeed;
and the results, when considered with due reference to the conditions
of the problem, are excellent: but in reality, if astronomers had
failed utterly to form any ideas whatever as to the sun's distance, if
for aught they knew the sun might be less than one million, or more
than a million millions of miles from us, the exactness of astronomy
as a science would be no whit impaired. And, in the second place, no
doubts whatever need be entertained as to the general inference from
astronomical observations that the sun's distance is between 92 and 93
millions of miles. All the measurements made during the last quarter
of a century lie between 90 and 95 millions of miles, and by far the
greater number of those made by the best methods, and under the most
favourable conditions, lie between 91 and 94 millions of miles. All
the very best cluster closely around a distance of 92-1/3 millions of
miles. We are not for the moment, however, concerned with the question
of the exact distance, but with the question whether astronomy has
obtained satisfactory evidence that the sun's distance lies in the
neighbourhood of the distances deduced by the various methods lately
employed. Putting the matter as one of probabilities, as all scientific
statements must be, it may be said as confidently that the sun's
distance lies between 85 millions and 100 millions of miles as that the
sun will rise to-morrow; and the probability that the sun's distance
is less than 90 millions, or greater than 95 millions of miles, is so
small that it may in effect be counted almost as nothing. Thirdly, the
possibility that the earth may be drawing nearer to the sun by three
or four millions of miles in a century may be dismissed entirely from
consideration. For, one of the inevitable consequences of such a change
of distance would be a change in the length of the year by about three
weeks; and so far from the year diminishing by twenty days or so in
length during a century, it has not diminished ten seconds in length
during the last two thousand years. If there has been any change year
by year in the earth's distance from the sun, it is one to be measured
by yards rather than by miles. Astronomers would be well content if
their 'probable error' in estimating the sun's distance could be
measured by thousands of miles; so that any possible approach of the
earth towards the sun would go but a very little way towards accounting
for the discrepancies between the different estimates of the distance,
even if these estimates grew always smaller as time passed, which is
assuredly not the case.
But in truth, if we consider the nature of the task undertaken by
astronomers in this case, we can only too readily understand that their
measurements should differ somewhat widely from each other. Let us
picture to ourselves for a moment the central sun, the earth, and the
earth's path, not as they really are, for the mind refuses altogether
to picture the dimensions even of the earth, which is but an atom
compared with the sun, whose own proportions, in turn, mighty though
they are, sink into utter insignificance compared with the enormous
scale of the orbit in which the earth travels around him. Let us reduce
the scale of the entire system to one 500-millionth part of its real
value: even then we have a tolerably large orbit to imagine. We must
picture to ourselves a fiery globe 3 yards in diameter to represent the
sun, and the earth as a one-inch ball circling round that globe at a
distance of about 325 yards, or about 350 paces. The diameter of the
earth's orbit would on this scale, therefore, be somewhat more than a
third of a mile. If we imagine the one-inch ball moving round the fiery
globe once in a year, while turning on its axis once in a day, we find
ourselves under a difficulty arising from the slowness of the resulting
motions. We should have found ourselves under a difficulty arising from
the rapidity of the actual motions if we had considered them instead.
The only resource is to reduce our time-scale, in the same way that we
have reduced our space-scale: but not in the same degree; for if we did
we should have the one-inch ball circling round its orbit, a third of
a mile in diameter, sixteen times in a second, and turning on its axis
five thousand times in a second. Say, instead, that for convenience we
suppose days reduced to seconds. Then we have to picture a one-inch
globe circling once in rather more than six minutes about a globe of
fire 3 yards in diameter, one-sixth of a mile from it, and turning
on its axis once in a second. We must further picture the one-inch
globe as inhabited by some 1,500 millions of creatures far too small
to be seen with the most powerful microscope--in fact, so small that
the tallest would be in height but about the seven-millionth of an
inch--and we must imagine that a few of these creatures undertake the
task of determining from their tiny home swiftly rotating as it rushes
in its orbit around a large globe of fire, 325 yards from them--the
number of yards really intervening between that globe and their home.
If we rightly picture these conditions, which fairly represent those
under which the astronomer has to determine the distance of the sun
from the earth, we shall perceive that the wonder rather is that any
idea of the sun's distance should be obtained at all, than that the
estimates obtained should differ from each other, and that the best of
them should err in measurable degree from the true distance.
Anything like a full explanation of the way in which transits of Venus
across the sun's face are utilised in the solution of the problem of
determining the sun's distance would be out of place in these pages.
But perhaps the following illustration may serve sufficiently, yet
simply, to indicate the qualities of the two leading methods of using
a transit. Imagine a bird flying in a circle round a distant globe
in such a way that, as seen from a certain window (a circular window
suppose), the bird will seem to cross the face of the globe once in
each circuit. Suppose that though the distance of the globe is not
known, the window is known to be exactly half as far again from the
globe as the bird's path is, and that the window is exactly a yard
in diameter. Now in the first place, suppose two observers watch the
bird, one (A) from the extreme right side, and the other (B) from the
extreme left side of the window, the bird flying across from right
to left. A sees the bird begin to cross the face of the globe before
B does,--say they find that A sees this exactly one second before B
does. But A's eye and B's being 3 feet apart, and the bird two-thirds
as far from the globe as the window is, the line traversed by the bird
in this interval is of course only 2 feet in length. The bird then
flies 2 feet in a second (this is rather slow for a bird, but the
principle of the explanation is not affected on that account). Say it
is further observed that he completes a circuit in exactly ten minutes
or six hundred seconds. Thus the entire length of a circuit is 1,200
feet,--whence by the well-known relation between the circumference and
the diameter of a circle, it follows that the diameter of the bird's
path is about 382 feet, and his distance from the centre of the globe
191 feet. So that the distance of the globe from the window, known to
be half as great again, is about 286-1/2 feet.
If we regard the globe as representing the sun; the window of known
size as representing our earth of known dimensions; the bird travelling
round in a known period and at a distance whose proportion to the
window's distance is known, as representing Venus travelling in a known
period round the sun and at a distance bearing a known proportion to
the earth's; this way of determining the distance of a remote globe
illustrates what is called Delisle's method of determining the sun's
distance. It requires that the two observers, A and B, should each make
exact note of the moment when the bird seemed to begin to cross the
disc of the remote globe; and in like manner Delisle's method requires
that two observers, widely separated on the earth in a direction
nearly parallel to that in which Venus is travelling, should make the
most exact note of the moment when Venus begins to cross the sun's
face. Also, as all I have said about the bird's beginning to cross
the face of the distant globe would apply equally well if said about
the end of his seeming passage across that disc, so two observers,
widely separated on the earth, can determine the sun's distance by
noting the end of her transit instead of the beginning, if they are
suitably placed for the purpose. The window of our illustration remains
unchanged during the bird's imagined flight, but as the face of the
earth turned sunwards (which corresponds to that window) is all the
time changing with the earth's rotation, a different pair of stations
would have to be selected for observing the end of transit, than would
be suitable for observing the beginning.
So much for the method called Delisle's. The other is in principle
equally simple. In the imaginary experiment just described we supposed
the two observers at the right and left sides of the circular window.
Imagine them now to watch the bird from the top and bottom of the
window, 3 feet apart. Suppose they note that the two tracks along
which, as seen from these two points, the bird seems to cross the
face of the distant globe, lie at a distance from each other equal to
one-third of the globe's apparent diameter. Now, the bird being twice
as far from the globe as from the window, the two tracks on the globe
necessarily lie twice as far apart as the two points from which they
are seen--or they lie 6 feet apart. The globe's diameter therefore
is 18 feet. Knowing thus how large it is, and knowing also how large
it looks, the observers know how far from them it lies. So, in the
Halleyan method of determining the sun's distance by observing Venus
in transit, astronomers are stationed far north and far south on the
sunlit half of the earth, corresponding to the window of the imaginary
experiment. Venus corresponds to the bird. The observers note along
what track she travels across the sun's face. (That they partially
determine this by noting how long she is in crossing, in no sense
affects the principle of the method.) They thus learn that such and
such a portion of the sun's diameter equals the distance separating
them,--some six or seven thousand miles perhaps,--whence the sun's
diameter is known. And as we know how large he looks, his distance from
the earth is determined.
A peculiarity distinguishing this method from the former is that the
observers must have a station whence the whole transit can be seen;
for practically the place of Venus's track can only be ascertained
satisfactorily by timing her passage across the sun's disc, so that
the beginning and end must be observed and very carefully timed. This
is to some degree a disadvantage; for during a transit lasting several
hours the earth turns considerably on her axis, and the face turned
sunwards at the beginning is thus very different from the face turned
sunwards at the end of transit. It is often exceedingly difficult
to find suitable northern and southern stations belonging to both
these faces of the earth. On the other hand, the other method has its
peculiar disadvantage. To apply it effectively, the observer must know
the exact Greenwich time (or any other selected standard time) at his
station,--or in other words he must know exactly how far east or west
his station is from Greenwich (or some other standard observatory).
For all the observations made by this method must be compared together
by some absolute time standard. In the Halleyan method the duration
of transit only is wanted, and this can be as readily determined by a
clock showing local time (or indeed by a clock set going a few minutes
before transit began and showing wrong time altogether, so only that
it goes at the right rate) as by a clock showing Greenwich, Paris, or
Washington time. The clock must not gain or lose in the interval. But a
clock which would gain or lose appreciably in four or five hours, would
be worthless to the astronomer; and any clock employed for scientific
observation might safely be trusted for an interval of that length;
whereas a clock which could be trusted to retain true time for several
days, is not so readily to be obtained.
We need not consider here the origin of the misapprehension (under
which our principal Government astronomer lay for some time), that
the Delislean method was alone available during the transit of 1874,
the Halleyan method, to use his words, 'failing totally.' The British
stations were selected while this misapprehension remained as yet
uncorrected. Fortunately the southern stations were suitable for
both methods. The northern were not: for this reason, simply, that
one set were so situated that night began soon after the beginning
of transit, which alone could be observed; while the other set were
so situated that night only came to an end a short time before the
transit ended, so that the end of transit only could be observed. No
doubt when the mistake just mentioned had been clearly recognised,--as
it was early in 1873,--measures would have been taken to rectify its
effect by occupying some suitable northern stations for observing the
whole transit, if Great Britain had been the only nation taking part
in the work. Fortunately, however, other nations might be trusted
to occupy the northern region, which had so long been overlooked.
England simply strengthened the southern observing corps: this could
be done without any change by which the Government astronomers would
have seemed to admit that 'some one had blundered.' Thus the matter
was arranged--America, Russia, and Germany occupying a large number
of stations admirably suited for applying the method which had been
supposed to 'fail totally.' The British Official astronomers, on whom
of course responsibility for adequately observing the transit (or
at least for properly applying money granted by the nation for the
purpose) alone rested, did in reality all, or nearly all, that was
necessary in doubling some of the southern observing parties, and
strengthening all of them; for unquestionably other nations occupied
suitable northern stations in sufficiently strong force.
It is to be remembered, however, in estimating the probable value
of the result which has been deduced from the British observations,
that as yet only a portion of these observations has been effectively
dealt with. The British observations of the beginning of transit at
northern and southern stations give, when combined together, a value
of the sun's distance. The British observations of the end of transit
at other northern and southern stations give also, when combined
together, a value of the sun's distance. And both sets combined give
of course a mean value of the sun's distance, more likely on the whole
to be correct than either value taken separately. But the British
observations of the duration of transit as observed from southern
stations do not of themselves give any means of determining the sun's
distance. They must be combined with observations of the duration of
transit as observed from northern stations; and no British party was
stationed where such observations could be obtained. The value, then,
of these particular British southern observations can only be educed
when comparison is made between them and the northern observations by
American, German, and Russian astronomers.
We must not, then, be disheartened if the results of the British
operations _alone_ should not seem to be altogether satisfactory. For
it may still happen that that portion of the British operations which
only has value when combined with the work of other countries may
be found to possess extreme value. We had good reason for doubting
beforehand whether results of any great value could be obtained by
Delisle's method. It was only because Halley's was supposed to fail
totally that the Government astronomers ever thought of employing that
method, which the experience of former transits had taught us to regard
as of very little value.
It may be asked, however, how we are to form an opinion from the result
of calculations based on the Delislean operations during the last
transit, whether the method in satisfactory or not. If as yet the sun's
distance is not exactly determined, a result differing from former
results may be better than any of them, many will think; and therefore
the method employed to obtain it may be more satisfactory than others.
If, they may reason, we place reliance on a certain method to measure
for us a certain unknown distance, how can we possibly tell from the
distance so determined whether the method is trustworthy or not?
Perhaps the readiest way of removing this difficulty, and also of
illustrating generally the principles on which the determination of
the most probable mean value of many different estimates depends, is
by considering a familiar experience of many, a case in which the
point to be determined is the most probable time of day. Suppose that
we are walking along a route where there are several clocks, the time
shown by our own watch being, for whatever reason, open to question.
We find, say, that as compared with our watch time, one clock is two
minutes fast, the next three minutes fast, the next one minute slow,
and so on, two or three perhaps being as much as six or seven minutes
fast, and two or three being as much as three or four minutes slow as
compared with the watch. We note, however, that these wider ranges of
difference occur only in the case of clocks presumably inferior--cheap
clocks in small shops, old clocks in buildings where manifestly the
flight of time is not much noted, and so forth. Rejecting these from
consideration, we find other clocks ranging from one minute or so
before our watch time to four minutes or so after it. Before striking
a rough average, however, we consider that some among these clocks are
placed where it is on the whole better to be a minute or two before the
time than a second late,--as, for instance, at banks, where there may
be occasion to send out clerks so as to make sure of reaching certain
places (Clearing-House, General Post-office, and so forth) within
specified time limits. On the other hand, we note that others of these
clocks are placed where it is better to be a minute or two after time
than a second before it,--as at railway stations, post-offices, and
so on, where it is essential that the public should be allowed time
fully up to a specified hour, for some particular service. Taking fair
account of such considerations, we might find that most probably the
true time lay between half a minute _before_ and two minutes and a
half _after_ our watch time. And thus we might infer that in reality
the true time was one minute or so later than that shown by our watch.
But if we were well acquainted with the characteristics of different
clocks along our route, we might infer the time (nay, we might to
all intents and purposes _know_ the time) far more accurately than
this. We might, for instance, pass six or seven shop-windows where
first-class specimens of horological work were shown,--in each window,
perhaps, several excellent clocks, with compensated pendulums and other
contrivances for securing perfect working. We might find at one of
these shops all such clocks showing the same time within two or three
seconds; at the next all such clocks also agreeing _inter se_ within
two or three seconds, but perhaps their mean differing from the mean
at the last shop of the kind by seven or eight seconds; and all six
or seven shops, while showing similar agreement as regards the clocks
severally displayed at each, agreeing also with each other so closely
that ten or twelve seconds would cover the entire range between their
several mean times. If this were observed, we should not hesitate to
place entire reliance on these special sets of clocks; and we should
feel certain that if we took the mean of all their means as the true
time (perhaps slightly modifying this mean in order to give due weight
to the known superiority of one or other of these clock-shops), we
should not be in error by more than five or six seconds, while most
probably we should have the time true within two or three seconds.
So far the illustration corresponds well with what had been done during
a quarter of a century or so before the last transit of Venus. Several
different methods of determining the sun's distance had been applied to
correct a value which for many reasons had come to be looked upon with
suspicion. This value--95,365,000 miles--was known to be certainly too
large. The methods used to test it gave results varying between about
90 million miles and about 96 million miles. But all the methods worthy
of any real reliance gave results lying between 91 million miles and
94 million miles. Not to enter more fully into details than would here
be suitable, we may pass on at once to say that those most experienced
in the matter recognised seven methods of determining the distance, on
which chief reliance must be placed. Of these seven methods, six--each
applied, of course, by many different observers--were dealt with
exhaustively by Professor Newcomb, of the Washington Observatory, a
mathematician who has undoubtedly given closer attention to the general
problem of determining the sun's distance than any living astronomer.
The six methods give six several results ranging from about 92,250,000
miles to about 92,850,000 miles; but when due weight is given to those
of the six methods which are undoubtedly the best, the most probable
mean value is found to be about 92,350,000 miles. The seventh method,
conceived by Leverrier, the astronomer to whom, with our own Adams,
the discovery of Neptune was due, and applied by him as he only could
have applied it (he alone possessing at once the necessary material and
the necessary skill), gives the value, 92,250,000 miles. From this it
may fairly be concluded that Newcomb's mean value, which has in fact
been accented by all American and Continental astronomers, is certainly
within 600,000 miles, and most probably within 300,000 miles of the
true mean distance of the sun.
But now, to revert to our illustrative case, let us suppose that after
passing the windows of six or seven horologists, from whose clocks we
have obtained such satisfactory evidence as to the probable hour, we
bethought ourselves of a place where, from what we had heard, a still
more exact determination of the hour might be obtained. While still
on the way, however, we learn from a friend certain circumstances
suggesting the possibility that the clocks at the place in question
may not be so correct as we had supposed. Persisting, however, in our
purpose, we arrive at the place, and carefully compare the indications
of the various clocks there with the time indicated by our watch,
corrected (be it supposed) in accordance with the results of our former
observations. Suppose now that the hour indicated by the various
clocks at this place, instead of agreeing closely with that which we
had thus inferred, differs from it by fully half a minute. Is it not
clear that instead of being led by this result to correct our former
estimate of the probable hour, we should at once infer that the doubts
which had been suggested as to the correctness of the various clocks
at this place were fully justified? The evidence of the other sets of
clocks would certainly not be invalidated by the evidence given by the
set last visited, even if the accuracy of these had not been called
in question. But if, as supposed, some good reason had been given for
doubt on this point,--as for instance, that of late the supervision
of the clocks had been interrupted,--we should not hesitate for a
moment to reject the evidence given by these clocks, or at least to
regard it as only tending to demonstrate what before we had been led
to surmise, namely, that these clocks could not be relied upon to show
true time. If however, furthermore, we found, not only that the mean
of the various times indicated by the clocks at this last-visited
place differed thus widely from the time which we had every reason
to consider very nearly exact, but that the different clocks here
differed as widely from each other, it would be absurd to rely upon
their evidence. The circumstance that there was a range of difference
of fully half a minute in their indications would of itself suffice
to show how untrustworthy they were, at least for the use of any one
who wished to obtain the time with great accuracy. Combined with the
observed difference between their mean time and that before obtained,
this circumstance would prove the inaccuracy of the clocks beyond all
possibility of doubt or question.
Now the case here imagined corresponds very closely with the
circumstances of the recent attempt to correct our estimate of the
sun's distance by Delisle's method. Our Government astronomers
bethought themselves of this method as likely to give the best
possible means for correcting, by observations of Venus in transit,
the estimate of the sun's distance which had been deduced by Newcomb,
and confirmed by Leverrier. While as yet their plans were not finally
decided upon, reasons for questioning this conclusion were indicated to
those officials by unofficial astronomers entertaining very friendly
feelings towards them. Retaining, however, their reliance on the
method thus called in question, they carried out their purpose, though
fortunately making provision, very nearly sufficient, for the use of
another method. Now, instead of the estimate of the sun's distance
obtained from the observations by Delisle's method agreeing closely
with Newcomb's mean value,--about 92,350,000 miles,--it exceeds this
value by about a million miles. (See, however, note on the last page
of this article.) According to various ways of considering the results
sent in by his observers, the chief official astronomer obtains a mean
value ranging from about 93,300,000 miles to about 93,375,000 miles.
The last named estimate seems preferred on the whole; but if we take
93,350,000 miles, we shall probably give about the fairest final
mean value. We have seen, however, that the results of observations
by seven distinct methods give values ranging only between 92,250,000
miles and 92,850,000 miles,--the six best methods giving values ranging
only between 92,250,000 miles and about 92,480,000 miles. The new
value thus lies 500,000 miles above the largest and admittedly the
least trustworthy of the seven results, 870,000 miles above the next
largest, a million miles above the mean value, and 1,100,000 miles
above the least value. It certainly ranges 500,000 miles above the
largest admissible value from those seven trusted methods, dealt with
most skilfully, cautiously, and laboriously, by such mathematicians as
Newcomb and Leverrier.
Can we hesitate as to the inference we should deduce from this result?
We need not for a moment call in question the skill or care with which
the British observing parties carried out their operations. Nor need we
doubt that the results obtained have been most skilfully and cautiously
investigated by those to whom the work of supervision and of reduction
has been entrusted. We need not even question the policy of devoting
so large a share of labour and expense to the employment of a method
held in little favour by most experienced Continental and American
astronomers, and objected to by many in England, including some even
among official astronomers. It was perhaps well that the method should
have one fair and full trial. And it is certain that all who have
taken part in the work have done their duty zealously and skilfully.
Captain Tupman, to whom Sir George Airy, our chief official astronomer,
entrusted the management of the calculations, has received, and justly,
from his official superior, the highest commendation for his energy and
discrimination. But beyond all manner of doubt the method employed has
failed under the test thus applied to it. I do not say that hereafter
the method may not succeed. Some of the conditions which at present
render it untrustworthy are such as may be expected to be modified
with the progress of improvement in the construction of scientific
instruments. But as yet the method is certainly not trustworthy.
This might be safely concluded from the wide discrepancy between
the new result and the mean of those before obtained. Yet if all
the various observations made by the British observing parties
agreed closely together, the circumstance, though it could hardly
shake our inference on this point, would yet cause some degree
of perplexity, since, of itself, it would seem to imply that the
method was trustworthy. Fortunately we are not thus troubled by
conflicting evidence. The indications of the untrustworthy nature of
the method, derived from the discordance between the results obtained
by it and those before inferred, are not a whit clearer, clear and
convincing though they are, than are the indications afforded by their
discordance _inter se_. The distance derived from northern and southern
observations of the beginning of transit ought of course to be the
same as that derived from northern and southern observations of the
end of transit. If both sets of observations were exactly correct, the
agreement between the results would be exact. The discordance between
them could only be wide as a consequence of some serious imperfection
in this method of observing a transit. But the discordance is _very_
wide. The observations of the beginning of transit by the British
parties give a distance of the sun exceeding by rather more than a
million miles that deduced from the observations of the end of transit.
I am well assured that neither Continental nor American astronomers
will accept the new estimate of the sun's distance, unless--which
I venture to predict will not be the case--the entire series of
transit observations should seem to point to the same value as the
most probable mean. Even then most astronomers will, I believe, think
rather that transits of Venus do not afford such satisfactory means
of determining the sun's distance as had been supposed. This opinion,
it is well known, was held by Leverrier, insomuch that he declined
to support with the weight of his influence the proposals for heavy
expenditure by France upon expeditions for observing the recent
transit and the approaching transit of the year 1882.
I doubt whether many, even among British astronomers, will accept
the new value. Already the Superintendent of the _Nautical Almanac_
has given his opinion upon it in terms which cannot be regarded as
favourable. 'It is well known,' he says (I quote at least from an
article which has been attributed to him without contradiction on
his part), 'that some astronomers have not expected our knowledge
of the sun's distance to be greatly improved from the observations
of the transit of Venus. Many, we can imagine, will regard with
some suspicion' so great a value as 93,300,000 miles (I substitute
these words for technical expressions identical in real meaning).
'Nevertheless, whatever degree of doubt might be entertained by
competent authorities, it appears to have been felt by those
immediately responsible for action, in different civilised nations
where science is encouraged, that so rare a phenomenon as a transit of
Venus could not be allowed to pass without every exertion being made to
utilise it.'
Sir George Airy, very naturally, attaches more value to the result of
the British expeditions, or at least of that part of the operations for
which he was responsible, than others are disposed to do. In an address
to the Astronomical Society, he expressed the opinion that 'the results
now presented are well worthy of very great confidence.... Considering
that the number of observers was eighteen, and that they made
fifty-four observations, and considering also the degree of training
they had, and their zeal, and the extreme care that was taken in the
choice of stations, I think,' he said, 'that there will not be anything
to compete with the value which has been deduced.' This is, as I have
said, very naturally his opinion; and although ordinarily it is rather
for the employers than for the employed to estimate the value of the
results sent in, yet at least we cannot object to his just and generous
praise of those who have worked under his orders.
Nevertheless, it must not be forgotten that on a former occasion
when equal satisfaction was expressed with the result of a rather
less costly but still a laborious and difficult experiment, the
scientific world did not accept (and has since definitely rejected)
the conclusion thus confidently advanced. I refer to the famous
Harton Colliery experiment for determining the mass of the earth.
The case is so closely analogous to that we are dealing with, that
it will be instructive briefly to describe its leading features.
Maskelyne, formerly the chief Government astronomer of this country,
from observations of the effect of the mass of Mount Schehallien in
deflecting a plumb-line, had inferred that the density of the earth
is five times that of water. Bouguer from observations in Chimborazo,
and Colonel James from observations on Arthur's Seat, had deduced
very similar results. From pendulum observations on high mountains,
Carlini and Plana made the earth's density very nearly the same.
Cavendish, Reich, and our own Francis Baily, weighed the earth against
two great globes of lead, by a method commonly known as the Cavendish
experiment, but really invented by Michell. These experiments agreed
closely together, making the earth's density about 5-1/2 times that of
water, or giving to the earth a mass equivalent to that which would
be contained in 6,000 millions of millions of millions of tons. Now,
from the Harton Colliery experiments, in 1854, in which the earth's
weight was estimated by comparing the vibrations of a pendulum at the
mouth of the mine with those of a similar pendulum at a depth of about
1,260 feet, it appeared that the earth's density is rather more than
6-1/2 times that of water, corresponding to an increase in our estimate
of the earth's mass by nearly 1,100 millions of millions of millions
of tons, or by more than a sixth of the entire mass resulting from
the most trustworthy former measurements. Sir G. Airy considered that
'this result will compete on at least equal terms with those obtained
by other methods;' but nearly a quarter of a century has passed during
which no competent astronomer has adopted this opinion, or even
suggested any modification of the former mean estimate of the earth's
mass on account of the unexpectedly large value deduced from the Harton
experiment.
It appears to me probable that a similar fortune will attend the latest
measurement of the sun's distance. But fortunately the matter will
not rest merely on measurements already made. Many fresh measurements
will be made during the next few years by methods already tried and
_not_ (like Delisle's transit method) found wanting. The recent
close approach of the planet Mars was not allowed to pass without a
series of observations specially directed to the determination of the
sun's distance; and we know that observations of Mars are among the
most advantageous means available for the solution of this difficult
problem. It was indeed from such observations that the first really
trustworthy measures of the sun's distance were obtained two centuries
ago. The small planets which travel in hundreds between the paths of
Mars and Jupiter have also been pressed into the service. And now so
many of these are known that scarcely a month passes without one or
other of them being favourably placed for the purpose of distance
measurements. For this too their star-like discs make these bodies
specially suitable.
The most probable inference respecting the results obtained by the
British expedition is that their chief value resides in the evidence
which they afford respecting the Delislean method of observation. They
seem to demonstrate what had before been only surmised (though with
considerable confidence by some astronomers), that this method cannot
be relied upon to correct our estimate of the sun's distance. In the
transit of 1882, which by the way will be visible in this country, we
may be certain that other and more satisfactory methods of observation
will be employed.
Before concluding, it may be well to make a few remarks upon some
misapprehensions which seem to exist as to the propriety in the first
place, and the desirability in the second, of comments upon the
arrangements adopted by Government astronomers to utilize particular
astronomical phenomena, and upon the value of the results which may
be obtained by means of such arrangements. Many seem to suppose that
astronomical matters are in some sense like military or naval (warlike)
manoeuvres, to be discussed effectively only by those who 'are under
authority, having (also) soldiers under them,' in other words by
Government astronomers. It would be very unfortunate for science
were this so, seeing that in that case those chiefly responsible for
the selection of methods and the supervision of operations would be
perfectly free from all possibility of criticism. No one under their
authority would be very likely to speak unfavourably of their plans.
And no one possessing higher general authority would be likely to have
any adequate knowledge of astronomy to form an opinion, either as to
the efficiency of the arrangements adopted in any case, or as to the
significance of the results obtained. In warlike matters, to some
degree, the wisdom of the strategy employed is tested by results which
all can appreciate, seeing that they affect directly the well-being of
the nation. Moreover, there are special reasons in these cases why in
the first place there should be a complete system of subordination,
and why in the second few should undertake the study of the science
unless they proposed to take their part in its practical application
and therefore to submit to its disciplinary system. But it is quite
otherwise with the science of astronomy. The nation requires, chiefly
for the regulation of its commerce, a certain number of trained
astronomers, to carry out systematically observations of a certain
class,--observations having in the main scarcely any closer relation
to the real living science of astronomy than land surveying has to
such geology as Lyell taught, or the bone-trade to the science of
anatomy. The stars by their diurnal motion form the most perfect
time-measurers, therefore they must be constantly timed by trained
observers. The sun and moon are the most effective time-indicators for
seamen, and therefore their movements must be most carefully noted.
Our _Nautical Almanac_ in fact embodies the kind of astronomical
materials which Government astronomers are employed to collect and
arrange. Such work may rather be called celestial surveying than
astronomy. But from the days of Flamsteed, the first of our Astronomers
Royal (as the chief Government astronomer is technically called) whose
contemporary, Newton, discovered the great law of the universe, to
those of Maskelyne and Sir G. Airy, whose contemporaries, the elder and
the younger Herschel, disclosed the structure of the universe, there
have always been astronomers outside the ranks of official astronomy,
in no way desirous of entering those ranks, and in fact so taking
their course from the beginning of their study of the science as to
preclude themselves from all possibility of undertaking any official
duties in astronomy. 'Non sua se voluntas,' necessarily, 'sed suæ vitæ
rationes, hoc aditu laudis, qui semper optimo cuique maxime patuit,
prohibuerunt:' though, indeed, it may not untruly be said that to one
who apprehends the true sublimity of astronomy as a science the routine
of official astronomy is by no means inviting, and probably personal
tastes have had very much to do with the choice, by such men, of the
more attractive departments of astronomy. Be this as it may, it is
certain that the astronomers who thus keep outside the official ranks
are not only free, and may not only be fully competent, to express an
opinion on the arrangements made by Government astronomers, or on the
results obtained by them, but as the only members of the community
who are at once free and able so to do, their right to speak may
often involve, in some degree, the duty of speaking. If through some
mistake wrong arrangements were proposed for instance,--and all men,
even officials (Herbert Spencer says, _especially_ officials), are
apt to make mistakes,--then, unless non-official astronomers, who had
carefully examined the subject, expressed their doubts, it is certain
that there would be no means whatever of correcting the error, or even
of detecting its consequence, until many years had elapsed. The leading
official astronomers would in such a case be apt, in fact they are apt
enough as it is, to stand by each other,--a chief in one department
commending the zeal and energy of the chief in another department,
this chief in turn commending the industry and ability of the other,
and so forth,--while subordinates of all ranks might be apt either to
maintain a judicious silence, or else at least to avoid any utterance
which would endanger their position. It may, on the one hand, be to
some degree questioned whether it would be fitting that discipline
should be so far neglected in such a case that a subordinate should
have eyes to see, or ears to hear, or thoughts to note, any error on
the part of his superior in office. And on the other hand, those who
know little or nothing of astronomy can of course form no opinion on
astronomical matters, however high they may be in authority outside
matters scientific. To assert, then, that it is either improper or
undesirable for unofficial astronomers to comment on the plans or
results of astronomers employed and paid by the nation is practically
equivalent to asserting that it is improper or undesirable for the
work of these paid astronomers to be examined at all,--a conclusion
manifestly absurd.[7]
FOOTNOTES:
[Footnote 7: The following lines are from a letter of mine, which
appeared in the _Times_ of April 13, some time after the present
article was written:--
'A few months ago I said in these columns that the determination of
the sun's distance, then recently communicated to Parliament--namely,
93,375,000 miles--was probably some 800,000 miles too great; and I
spoke of the method on which the determination was based as to some
degree discredited by the wide range of difference both between that
result and the mean of the best former measurements, and between the
several results of which that one was itself the mean. Captain Tupman,
as straightforward as he is skilful and zealous, announces as the
result of a re-examination of the British observations a distance
about 600,000 miles less than the above, or, more exactly, about
92,790,000 miles, as the sun's mean distance. But while he obtains from
the ingress observations a mean distance of only 92,300,000 miles,
he obtains from the egress observations a mean distance of about
93,040,000 miles; and the value, 92,790,000 miles, is only obtained as
the mean of these two values duly weighted, the egress observations
being more satisfactory than the ingress observations. 'It appears to
me that the doubts which I formerly expressed as to the trustworthiness
of the method employed, are to some degree justified.
'To the general public it will be more interesting to inquire what
probably is the true mean distance of the sun. To this it may be
replied that in all probability the sun's mean distance does not lie so
much as 600,000 miles on either side of the value 92,300,000 miles' (it
should be 92,400,000).]
_THE PAST HISTORY OF OUR MOON._
The moon, commonly regarded as a mere satellite of the earth, is
in truth a planet, the least member of that family of five bodies
circling within the asteroidal zone, to which astronomers have given
the name of the terrestrial planets. There can be no question that
this is the true position of the moon in the solar system. In fact,
the fashion of regarding her as a mere attendant of our earth may be
looked upon as the last relic of the old astronomy in which our earth
figured as the fixed centre of the universe, and the body for whose
sake all the celestial orbs were fashioned. In this aspect, also, the
moon is a far more interesting object of research than when viewed as
belonging to another and an inferior order. We are able to recognise,
in her, appearances probably resulting from the relative smallness of
her dimensions, and hence to derive probable information as to the
condition of other orbs in the solar system which fall below the earth
in point of size. Precisely as the study of the giant planets, Jupiter
and Saturn, has led astronomers to infer that certain peculiarities
must result from vastness of dimensions, so the study of the dwarf
planets, Mars, our moon, and Mercury, may indicate the relations we are
to associate with inferiority of size.
This thought immediately introduces us to another conception, which
causes us to regard with even greater interest the evidence afforded
by the moon's present condition. It can scarcely be questioned that
the size of any member of the solar system, or rather the quantity
of matter in its orb, assigns, so to speak, the duration of that
orb's existence, or rather of the various stages of that existence.
The smaller body must cool more rapidly than the larger, and hence
the various periods during which the former is fit for this or that
purpose of planetary life (I speak with purposed vagueness here) are
shorter than the corresponding periods in the life of the latter.
Thus the sun, viewed in this way, is the youngest member of the solar
system, while the tiniest members of the asteroid family, if not the
oldest in reality, are the oldest to which the telescope has introduced
us. Jupiter and Saturn come next to the sun in youth; they are still
passing through the earliest stages of planetary existence, even if we
ought not rather to adopt that theory of their condition which regards
them as subordinate suns, helping the central sun to support life on
the satellites which circle around them. Uranus and Neptune are in
a later stage, and perchance when telescopes have been constructed
large enough to study these planets with advantage, we may learn
something of that stage, interesting as being intermediate to the
stages through which our earth and Venus on the one hand, and the giant
brothers Jupiter and Saturn on the other, are at present passing. After
our earth and Venus, which are probably at about the same stage of
planetary development (though owing to the difference in their position
they may not be equally adapted for the support of life), we come to
Mars and Mercury, both of which must be regarded as in all probability
much more advanced and in a sense more aged than the earth on which
we live. In a similar sense,--even as an ephemeron is more aged after
a few hours of existence than a man after as many years,--the small
planet which we call 'our moon' may be described as in the very
decrepitude of planetary existence, nay (some prefer to think), as even
absolutely dead, though its lifeless body still continues to advance
upon its accustomed orbit, and to obey the law of universal attraction.
Considerations such as these give singular interest to the discussion
of the past history of our moon, though they add to the difficulty of
interpreting the problems she presents to us. For we have manifestly to
differentiate between the effects due to the moon's relative smallness
on the one hand, and those due to her great age on the other. If
we could believe the moon to be an orb which simply represents the
condition to which our earth will one day attain, we could study her
peculiarities of appearance with some hope of understanding how they
had been brought about, as well as of learning from such study the
future history of our own earth. But clearly the moon has had another
history than our earth. Her relative smallness has led to relations
such as the earth never has presented and never will present. If our
earth is, as astronomers and physicists believe, to grow dead and cold,
all life perishing from her surface, it is tolerably clear, from what
we already know of her history, that the appearance she will present
in her decrepitude will be utterly unlike that presented by the moon.
Grant that after the lapse of enormous time-intervals the oceans now
existing on the earth will be withdrawn beneath her solid crust,
and even (which seems incredible) that at a more distant future the
atmosphere now surrounding her will have become greatly reduced in
quantity, either by similar withdrawal or in any other manner, yet the
surface of the earth would present few features of resemblance to that
of the moon. Viewed from the distance at which we view the moon, there
would be few crateriform mountains indeed compared with those on the
moon; those visible would be small by comparison with lunar craters
even of medium dimensions; and the radiated regions seen on the moon's
surface would have no discernible counterpart on the surface of the
earth. The only features of resemblance, under the imagined conditions,
would be probably the partially flat sea bottoms (though these would
bear a different proportion to the more elevated regions) and the
mountain ranges, the only terrestrial features of volcanic disturbance
which would be relatively more important than their lunar counterparts.
I do not purpose, however, to discuss the probable future of the
earth, having only indicated the differences just touched upon in order
to remind the reader at the outset that we have not in 'the moon' a
representation of the earth at any stage of her history. Other and
different relations are presented for our consideration, although it
may well be that by carefully discussing them we may learn somewhat
respecting our earth, as also respecting the past history and future
development of the solar system.
It appears reasonable to regard the moon, after her first formation as
a distinct orb, as presenting the same general characteristics that we
ascribe to our earth in its primary stage as a planet. In one respect
the moon, even at that early stage, may have differed from the earth.
I refer to its rotation, the correspondence between which and its
revolution may probably have existed from the moon's first formation.
But this would not materially have affected the relations with which we
have to deal at present. We may apply, then, to the moon the arguments
which have been applied to the discussion of the first stages of our
earth's history.
Adopting this view, we see that at the first stage of its existence
as an independent planet, the moon must have been an intensely heated
gaseous globe, glowing with inherent light, and undergoing a process of
condensation, 'going on at first at the surface only, until by cooling
it must have reached the point where the gaseous centre was exchanged
for one of combined and liquefied matter.' To apply now to the moon at
this stage the description which Dr. Sterry Hunt gives of the earth.
'Here commences the chemistry of the moon. So long as the gaseous
condition of the moon lasted, we may suppose the whole mass to have
been homogeneous; but when the temperature became so reduced that the
existence of chemical compounds at the centre became possible, those
which were most stable at the elevated temperature then prevailing
would be first formed. Thus, for example, while compounds of oxygen
with mercury, or even with hydrogen, could not exist, oxides of
silicon, aluminium, calcium, magnesium, and iron, might be formed and
condensed in a liquid form at the centre of the globe. By progressive
cooling still other elements would be removed from the gaseous mass,
which would form the atmosphere of the non-gaseous nucleus.' 'The
processes of condensation and cooling having gone on until those
elements which are not volatile in the heat of our ordinary furnaces
were condensed into a liquid form, we may here inquire what would be
the result on the mass of a further reduction of temperature. It is
generally assumed that in the cooling of a liquid globe of mineral
matter congelation would commence at the surface, as in the case of
water; but water offers an exception to most other liquids, inasmuch as
it is denser in the liquid than in the solid form. Hence, ice floats
on water, and freezing water becomes covered with a layer of ice which
protects the liquid below. Some metals and alloys resemble water in
this respect. With regard to most other earthy substances, and notably
the various minerals and earthy compounds like those which may be
supposed to have made up the mass of the molten globe, the case is
entirely different. The numerous and detailed experiments of Charles
Deville and those of Delesse, besides the earlier ones of Bischoff,
unite in showing that the density of fused rocks is much less than that
of the crystalline products resulting from their slow cooling, these
being, according to Deville, from one-seventh to one-sixteenth heavier
than the fused mass, so that if formed at the surface they would, in
obedience to the laws of gravity, tend to sink as soon as formed.'
Here it has to be noted that possibly there existed a period (for
our earth as well as for the moon) during which, notwithstanding the
relations indicated by Dr. Hunt, the exterior portions of the moon
were solid, while the interior remained liquid. A state of things
corresponding to what we recognise as possible in the sun may have
existed. For although undoubtedly any liquid matter forming in the
sun sinks in obedience to the laws of gravity towards the centre, yet
the greater heat which it encounters as it sinks must vapourise it,
notwithstanding increasing pressure, so that it can only remain liquid
near the region where rapid radiation allows of sufficient cooling
to produce liquefaction. And in the same way we may conceive that
the solidification taking place at any portion of the surface of the
moon's or the earth's liquid globe, owing to rapid radiation of heat
thence, although it might be followed immediately by the sinking of the
solidified matter, would yet result in the continuance (rather than the
existence) of a partially solid crust. For the sinking solid matter,
though subjected to an increase of pressure (which, in the case of
matter expanding on liquefaction, would favour solidification), would
nevertheless, owing to the great increase of heat, become liquefied,
and, expanding, would no longer be so much denser[8] than the liquid
through which it was sinking as to continue to sink rapidly.
Nevertheless, it is clear that after a time the heat of the interior
parts of the liquid mass would no longer suffice to liquefy the solid
matter descending from the surface, and then would commence the process
of aggregation at the centre described by Dr. Hunt. The matter forming
the solid centre of the earth consists probably of metallic and
metalloidal compounds of elements denser than those forming the known
portions of the earth's crust.[9] In the case of the moon, whose mean
density is very little greater than the mean density of the matter
forming the earth's crust, we must assume that the matter forming the
solid nucleus at that early stage was relatively less in amount, or
else that we may attribute part of the difference to the comparatively
small force with which lunar gravity operated during various stages of
contraction and solidification.
In the case of the moon, as in that of the earth, before the last
portions became solidified, there would exist a condition of imperfect
liquidity, as conceived by Hopkins, 'preventing the sinking of the
cooled and heavier particles, and giving rise to a superficial crust,
from which solidification would proceed downwards. There would thus
be enclosed between the inner and outer solid parts a portion of
uncongealed matter,' which may be supposed to have retained its
liquid condition to a late period, and to have been the principal
seat of volcanic action, whether existing in isolated reservoirs or
subterranean lakes, or whether, as suggested by Scrope, forming a
continuous sheet surrounding the solid nucleus.
Thus far we have had to deal with relations more or less involved
in doubt. We have few means of forming a satisfactory opinion as to
the order of the various changes to which, in the first stages of
her existence as a planet, our moon was subject. Nor can we clearly
define the nature of those changes. In these matters, as with the
corresponding processes in our earth's case, there is much room for
variety of opinion.
But few can doubt that, by whatever processes such condition may have
been attained, the moon, when her surface began to form itself into its
present appearance, consisted of a globe partially molten surrounded
by a crust at least partially solidified. Some portions of the actual
surface may have remained liquid or viscous later than others but at
length the time must have arrived when the radiating surface was almost
wholly solid. It is from this stage that we have to trace the changes
which have led to the present condition of the moon's surface.
It can scarcely be questioned that those seismologists are in the
right who have maintained in recent times the theory that in the
case of a cooling globe, such as the earth or moon at the stage just
described, the crust would in the first place contract more quickly
than the nucleus, while later the nucleus would contract more quickly
than the crust. This amounts, in fact, to little more than the
assertion that the process of heat radiation from the surface would be
more rapid, and so last a shorter time than the process of conduction
by which in the main the nucleus would part with its heat. The crust
would part rapidly with its heat, contracting upon the nucleus; but
the very rapidity (relative) of the process, by completing at an early
stage the radiation of the greater portion of the heat originally
belonging to the crust, would cause the subsequent radiation to be
comparatively slow, while the conduction of heat from the nucleus
to the crust would take place more rapidly, not only relatively but
actually.
Now it is clear that the results accruing during the two stages into
which we thus divide the cooling of the lunar globe would be markedly
different. During the first stage forces of tension (tangential) would
be called to play in the lunar crust; during the later stage the forces
would be those of pressure.
Taking the earlier stage, during which the forces would be tensional,
let us consider in what way these forces would operate.
At the beginning, when the crust would be comparatively thin, I
conceive that the more general result of the rapid contraction of
the crust would be the division of the crust into segments, by the
formation of numerous fissures due to the lateral contraction of
the thin crust. The molten matter in these fissures would film over
rapidly, however, and all the time the crust would be growing thicker
and thicker, until at length the formation of distinct segments would
no longer be possible. The thickening crust, plastic in its lower
strata, would now resist more effectively the tangential tensions,
and when yielding would yield in a different manner. It was at this
stage, in all probability, that processes such as those illustrated by
Nasmyth's globe experiments took place, and that from time to time the
crust yielded at particular points, which became the centres of systems
of radiating fissures. Before proceeding, however, to consider the
results of such processes, let it be noted that we have seen reason to
believe that among the very earliest lunar formations would be rifts
breaking the _ancient_ surface of the lunar crust. I distinguish in
this way the ancient surface from portions of surface whereof I shall
presently have to speak as formed at a later time.
Now let us conceive the somewhat thickened crust contracting upon
the partially fluid nucleus. If the crust were tolerably uniform in
strength and thickness we should expect to find it yielding (when
forced to yield) at many points, distributed somewhat uniformly over
its extent. But this would not be the case if--as we might for many
reasons expect--the crust were wanting in uniformity. There would
be regions where the crust would be more plastic, and so readier to
yield to the tangential tensions. Towards such portions of the crust
the liquid matter within would tend, because there alone would room
exist for it. The down-drawing, or rather in-drawing, crust elsewhere
would force away the liquid matter beneath, towards such regions of
less resistance, which would thus remain at (and be partly forced
to) a higher level. At length, however, the increasing tensions thus
resulting would have their natural effect; the crust would break
open at the middle of the raised region, and in radiating rifts,
and the molten matter would find vent through the rifts as well as
at the central opening. The matter so extruded, being liquid, would
spread, so that--though the radiating nature of the rifts would still
be indicated by the position of the extruded matter--there would
be no abrupt changes of level. It is clear, also, that so soon as
the outlet had been formed the long and slowly sloping sides of the
region of elevation would gradually sink, pressing the liquid matter
below towards the centre of outlet, whence it would continue to pour
out so long as this process of contraction continued. All round the
borders of the aperture the crust would be melted, and would continue
plastic long after the matter which had filled the fissures and flowed
out through them had solidified. Thus there would be formed a wide
circular orifice, which would from the beginning be considerably above
the mean level of the moon's surface, because of the manner in which
the liquid matter within had been gathered there by the pressure of
the surrounding slopes.[10] Moreover, around the orifice, the matter
outflowing as the crust continued to contract would form a raised wall.
Until the time came when the liquid nucleus began to contract more
rapidly than the crust, the large crateriform orifice would be full
to the brim (or nearly so), at all times, with occasional overflows:
and as a writer who has recently adopted this theory has remarked, 'We
should ultimately have a large central lake of lava surrounded by a
range of hills, terraced on the outside,--the lake filling up the space
they enclosed.'
The crust might burst in the manner here considered, at several
places at the same--or nearly the same--time, the range of the
radiating fissures, depending on the extent of the underlying lakes
of molten matter thus finding their outlet; or there might be a
series of outbursts at widely separated intervals of time and at
different regions, gradually diminishing in extent as the crust
gradually thickened and the molten matter beneath gradually became
reduced in relative amount. Probably the latter view should be
accepted, since, if we consider the three systems of radiations from
Copernicus, Aristarchus, and Kepler, which were manifestly not formed
contemporaneously, but in the order in which their central craters have
just been named, we see that their dimensions diminished as their date
of formation was later. According to this view we should regard the
radiating system from Tycho as the oldest of all these formations.
At this very early stage of the moon's history, then, we regard the
moon as a somewhat deformed spheroid, the regions whence the radiations
extended being the highest parts, and the regions farthest removed from
the ray centres being the lowest.[11] To these lower regions whatever
was liquid on the moon's surface would find its way. The down-flowing
lava would not be included in this description, as being rather viscous
than liquid; but if any water existed at that time it would occupy the
depressed regions which at the present time are called Maria or Seas.
It is a question of some interest, and one on which different opinions
have been entertained, whether the moon at any stage of its existence
had oceans and an atmosphere corresponding in relative extent to
those of the earth. It appears to me that, apart from all the other
considerations which have been suggested in support of the view that
the moon formerly had oceans and an atmosphere, it is exceedingly
difficult to imagine how, under any circumstances, a globe so large
as the moon could have been formed under conditions not altogether
unlike, as we suppose, those under which the earth was formed (having
a similar origin, and presumably constructed of the same elements),
without having oceans and an atmosphere of considerable extent. The
atmosphere would not consist of oxygen and nitrogen only or chiefly,
any more than, in all probability, the primeval atmosphere of our
own earth was so constituted. We may adopt some such view of the
moon's atmosphere--_mutatis mutandis_--as Dr. Sterry Hunt has adopted
respecting the ancient atmosphere of the earth. Hunt, it will be
remembered, bases his opinion on the former condition of the earth by
conceiving an intense heat applied to the earth as now existing, and
inferring the chemical results. 'To the chemist,' he remarks, 'it is
evident that from such a process applied to our globe would result the
oxidation of all carbonaceous matter; the conversion of all carbonates,
chlorides, and sulphates into silicates; and the separation of the
carbon, chlorine, and sulphur in the form of acid gases; which,
with nitrogen, watery vapour, and an excess of oxygen, would form an
exceedingly dense atmosphere. The resulting fused mass would contain
all the bases as silicates, and would probably nearly resemble in
composition certain furnace-slags or basic volcanic glasses. Such we
may conceive to have been the nature of the primitive igneous rock,
and such the composition of the primeval atmosphere, _which must have
been one of very great density_.' All this, with the single exception
of the italicised remark, may be applied to the case of the moon. The
lunar atmosphere would not probably be dense at that primeval time,
even though constituted like the terrestrial atmosphere just described.
It would perhaps have been as dense, or nearly so, as our present
atmosphere. Accordingly condensation would take place at a temperature
not far from the present boiling-point, and the lower levels of
the half-cooled crust would be drenched with a heated solution of
hydrochloric acid, whose decomposing action would be rapid, though
not aided--as in the case of our primeval earth--by an excessively
high temperature. 'The formation of the chlorides of the various bases
and the separation of silica would go on until the affinities of the
acid were satisfied.' 'At a later period the gradual combination of
oxygen with sulphurous acid would eliminate this from the atmosphere
in the form of sulphuric acid.' 'Carbonic acid would still be a large
constituent of the atmosphere, but thenceforward (that is, after the
separation of the compounds of sulphur and chlorine from the air) there
would follow the conversion of the complex aluminous silicates, under
the influence of carbonic acid and moisture, into a hydrated silicate
of alumina or clay, while the separated lime, magnesia, and alkalies
would be changed into bicarbonates, and conveyed to the sea in a state
of solution.'
It seems to me that it is necessary to adopt some such theory as to
the former existence of lunar oceans in order to explain some of the
appearances presented by the so-called lunar seas. As regards the
present absence of water we may adopt the theory of Frankland, that the
lunar oceans have withdrawn beneath the crust as room was provided for
them by the contraction of the nucleus. I think, indeed, that there
are good grounds for looking with favour on the theory of Stanislas
Meunier, according to which the oceans surrounding any planet--our own
earth or Mars, for example--are gradually withdrawn from the surface to
the interior. And in view of the enormous length of the time-intervals
required for such a process, we must consider that while the process
was going on the lunar atmosphere would not only part completely with
the compounds of sulphur, chlorine, and carbon, but would be even
still further reduced by chemical processes acting with exceeding
slowness, yet effectively in periods so enormous. But without insisting
on this consideration, it is manifest that--with very reasonable
assumptions as to the density of the lunar atmosphere in its original
complex condition--what would remain after the removal of the chief
portion by chemical processes, and after the withdrawal of another
considerable portion along with the seas beneath the lunar crust, would
be so inconsiderable in quantity as to accord satisfactorily with
the evidence which demonstrates the exceeding tenuity of any lunar
atmosphere at present existing.
These considerations introduce us to the second part of the moon's
history,--that corresponding to the period when the nucleus was
contracting more rapidly than the crust.
One of the first and most obvious effects of this more rapid nuclear
contraction would be the lowering of the level of the molten matter,
which up to this period had been kept up to, or nearly up to, the
lips of the great ringed craters. If the subsidence took place
intermittently there would result a terracing of the interior of the
ringed elevation, such as we see in many lunar craters. Nor would
there be any uniformity of level in the several crater floors thus
formed, since the fluid lava would not form parts of a single fluid
mass (in which case, of course, the level of the fluid surface would
be everywhere the same), but would belong to independent fluid masses.
Indeed it may be noticed that the very nature of the case requires us
to adopt this view, since no other will account for the variety of
level observed in the different lunar crater-floors. If these ceased to
be liquid at different times, the independence of the fluid masses is
by that very fact established; and if they ceased to be liquid at the
same time, they must have been independent, since, if communication had
existed between them, they would have shown the uniformity of surface
which the laws of hydrostatics require.[12]
The next effect which would follow from the gradual retreat of
the nucleus from the crust (setting aside the withdrawal of lunar
seas) would be the formation of corrugations,--in other words, of
mountain-ranges. Mallet describes the formation of mountain-chains as
belonging to the period when 'the continually increasing thickness of
the crust remained such that it was still as a whole flexible enough,
or opposed sufficient resistance of crushing to admit of the uprise of
mountain-chains by resolved tangential pressures.' Applying this to the
case of the moon, I think it is clear that--with her much smaller orb
and comparatively rapid rate of cooling--the era of the formation of
mountain-chains would be a short one, and that these would therefore
form a less important characteristic of her surface than of the
earth's. On the other hand, the period of volcanic activity which would
follow that of chain-formation would be _relatively_ long continued;
for regarding this period as beginning when the thickness of the moon's
crust had become too great to admit of adjustment by corrugation, the
comparatively small pressure to which the whole mass of the moon had
been subjected by lunar gravity, while it would on the one hand cause
the period to have an earlier commencement (relatively), would on the
other leave greater play to the effects of contraction. Thus we can
understand why the signs of volcanic action, as distinguished from the
action to which mountain-ranges are due, should be far more numerous
and important on the moon than on the earth.
I do not, however, in this place enter specially into the consideration
of the moon's stage of volcanic activity, because already, in the pages
of my Treatise on the Moon (Chapter VI.), I have given a full account
of that portion of my present subject. I may make a few remarks,
however, on the theory respecting lunar craters touched on in my work
on 'The Moon.' I have mentioned the possibility that some among the
enormous number of ring-shaped depressions which are seen on the moon's
surface may have been the result of meteoric downfalls in long past
ages of the moon's history. One or two critics have spoken of this view
as though it were too fantastic for serious consideration. Now, though
I threw out the opinion merely as a suggestion, distinctly stating
that I should not care to maintain it as a theory, and although my
own opinion is unfavourable to the supposition that any of the more
considerable lunar markings can be explained in the suggested way, yet
it is necessary to notice that on the general question whether the
moon's surface has been marked or not by meteoric downfalls scarcely
any reasonable doubts can be entertained. For, first, we can scarcely
question that the moon's surface was for long ages plastic, and though
we may not assign to this period nearly so great a length (350 millions
of years) as Tyndall--following Bischoff--assigns to the period when
our earth's surface was cooling from a temperature of 2000° C. to
200°, yet still it must have lasted millions of years; and, secondly,
we cannot doubt that the process of meteoric downfall now going on is
not a new thing, but, on the contrary, is rather the final stage of a
process which once took place far more actively. Now Prof. Newton has
estimated, by a fair estimate of observed facts, that each day on the
average 400 millions of meteors fall, of all sizes down to the minutest
discernible in a telescope, upon the earth's atmosphere, so that on
the moon's unprotected globe--with its surface one thirteenth of the
earth's--about 30 millions fall each day, even at the present time. Of
large meteoric masses only a few hundreds fall each year on the earth,
and perhaps about a hundred on the moon; but still, even at the present
rate of downfall, millions of large masses _must_ have fallen on the
moon during the time when her surface was plastic, while _probably_ a
much larger number--including many much larger masses--must have fallen
during that period. Thus, not only without straining probabilities, but
by taking only the most probable assumptions as to the past, we have
arrived at a result which compels us to believe that the moon's surface
has been very much marked by meteoric downfall, while it renders it by
no means unlikely that a large proportion of the markings so left would
be discernible under telescopic scrutiny.
I would, in conclusion, invite those who have the requisite leisure to
a careful study of the distribution of various orders of lunar marking.
It would be well if the moon's surface were isographically charted,
and the distribution of the seas, mountain ranges, and craters of
different dimensions and character, of rills, radiating streaks, bright
and dark regions, and so on, carefully compared _inter se_, with the
object of determining whether the different parts of the moon's surface
were probably brought to their present condition during earlier or
later periods, and of interpreting also the significance of the moon's
characteristic peculiarities. In this department of astronomy, as in
some others, the effectiveness of well-devised processes of charting
has been hitherto overlooked.
FOOTNOTES:
[Footnote 8: It would still be somewhat denser, because under the
circumstances it would be somewhat cooler.]
[Footnote 9: It is thus, and not by the effects due to increasing
pressure (effects which probably do not increase beyond a certain
point), that we are to explain the fact that the earth's density as a
whole is about twice the mean density of the matters which form its
solid surface. It may be that this consideration, supported by the
results of recent experimental researches, may give a significance
hitherto not noted to the relatively small mean density of the moon.]
[Footnote 10: I have occasion to make some remarks at this stage
to avoid possible and (my experience has shown me) not altogether
improbable misconception, or even misrepresentation. The theory
enunciated above will be regarded by some, who may have read a certain
review of my Treatise on the Moon, as totally different from what I
have advocated in that work, and, furthermore, as a theory which I
have borrowed from the aforesaid review. I should not be particularly
concerned if I had occasion to modify views I had formerly expressed,
since I apprehend that every active student of science should hope,
rather than dread, that as his work proceeds he would form new
opinions. But I must point out that earlier in my book I had advocated
the theory urged above. After describing the radiations from Tycho
and other craters, I proceed as follows in chapter iv.--'It appears
to me impossible to refer these phenomena to any general cause but
the reaction of the moon's interior overcoming the tension of the
crust, and to this degree Nasmyth's theory seems correct; but it
appears manifest, also, that the crust cannot have been fractured
in the ordinary sense of the word. Since, however, it results from
Mallet's investigations that the tension of the crust is called into
play in the earlier stages of contraction, and its power to resist
contraction in the later stages,--in other words, since the crust at
first contracts faster than the nucleus, and afterwards not so fast as
the nucleus,--we may assume that the radiating systems were formed in
so early an era that the crust was plastic. And it seems reasonable to
conclude that the outflowing matter would retain its liquid condition
long enough (the crust itself being intensely hot) to spread widely,--a
circumstance which would account at once for the breadth of many of
the rays, and for the restoration of level to such a degree that no
shadows are thrown. It appears probable, also, that not only (which is
manifest) were the craters formed later which are seen around and upon
the radiations, but that the central crater itself acquired its actual
form long after the epoch when the rays were formed.']
[Footnote 11: Where several ray centres are near together, a region
directly between two ray centres would be at a level intermediate
between that of the ray centres and that of a region centrally placed
within a triangle or quadrangle of ray centres; but the latter region
might be at a higher level than another very far removed from the part
where the ray centres were near together. For instance, the space in
the middle of the triangle having Copernicus, Aristarchus, and Kepler
at its angles (or more exactly between Milichius and Bessarion) is
lower than the surface around Hortensius (between Copernicus and
Kepler), but not so low as the Mare Imbrium, far away from the region
of ray centres of which Copernicus, Aristarchus, and Kepler are the
principal.]
[Footnote 12: It is important to notice that we may derive from these
considerations an argument as to the condition of the fluid matter now
existing beneath the solid crust of the earth.]
_A NEW CRATER IN THE MOON._
Dr. Klein, a German astronomer, has recently called the attention of
astronomers to a lunar crater some three miles wide, which had not
before been observed, and which, he feels sure, was not in existence
two years ago. Astronomers have long since given up all hope of tracing
either the signs of actual life upon the moon or traces of the past
existence of living creatures there. But there are still among them
those who believe that by sedulous and careful scrutiny processes of
material change may be recognised in that seemingly inert mass. In
reality, perhaps, the wonder rather is that signs of change should
not be often recognised, than that from time to time a new crater
should appear or the walls of old craters fall in. The moon's surface
is exposed to variations of temperature compared with which those
affecting the surface of our earth are altogether trifling. It is
true there is no summer or winter in the moon. Sir W. Herschel has
spoken of the lunar seasons as though they resembled our own, but
in reality they are very different. The sun's midday height at any
lunar station is only about three degrees greater in summer than in
winter; whereas our summer sun is 47° higher in the sky at noon than
our winter sun. In fact, a midsummer's day on the moon does not differ
more from a midwinter's day, as far as the sun's actual path on the
sky is concerned, than with us the 17th of March differs from the
25th, or the 19th of September from the 27th. It is the change from
day to night which chiefly affects the moon's surface. In the lunar
year of seasons, lasting 346-2/3 of our days, there are only 11-3/4
lunar days, each lasting 29-3/4 of ours. Thus day lasts more than a
fortnight, and is followed by a night of equal length. Nor is this
all. There is neither air nor moisture to produce such effects as are
produced by our air and the moisture it contains in mitigating the heat
of day and the cold of night. Under the sun's rays the moon's surface
becomes hotter and hotter as the long lunar day proceeds, until at
last its heat exceeds that of boiling water. But so soon as the sun
has set the heat thus received is rapidly radiated away into space (no
screen of moisture-laden air checking its escape), and long before
lunar midnight a cold exists compared with which the bitterest weather
ever experienced by Arctic voyagers would be oppressively hot. These
are not merely theoretical conclusions, though even as such they could
be thoroughly relied upon. The moon's heat has been measured by the
present Lord Rosse (using his father's splendid six-feet mirror). He
separated the heat which the moon simply reflects to us from that which
her heated surface itself gives out (or, technically, he separated
the reflected from the radiated heat), by using a glass screen which
allowed the former heat to pass while it intercepted the latter. He
thus found that about six-sevenths of the heat we receive from the moon
is due to the heating of her own substance. From the entire series of
observations it appeared that the change of temperature during the
entire lunar day--that is, from near midnight to near midday on the
moon--amounts to fully 500° Fahrenheit. If we assume that the cold at
lunar midnight corresponds with about 250° below zero (the greatest
cold experienced in Arctic travelling has never exceeded 140° below
zero), it would follow that the midday heat is considerably greater
than that of boiling water on the earth at the sea-level. But the range
of change is not a matter of speculation. It certainly amounts to about
500°, and in whatever way we distribute it, we must admit, first, that
no such life as we are familiar with could possibly exist on the moon;
and, secondly, that the moon's crust must possess a life of its own,
so to speak, expanding and contracting unceasingly and energetically.
Professor Newcomb, by the way, in his fine work on Popular Astronomy,
rejects the idea that the expansions and contractions due to these
great changes of temperature can cause any disintegration at the
present time. There might, he says, be bodies so friable that they
would crumble, 'but whatever crumbling might thus be caused would soon
be done with, and then no further change would occur.' For my own part,
I cannot consider that such a surface as the moon at present possesses
can undergo these continual expansions and contractions without slow
disintegration. It seems to me also extremely probable that from time
to time the overthrow of great masses, the breaking up of arched
crater-floors, and other sudden changes discernible from the earth,
might be expected to occur. Professor Newcomb has, I conceive, omitted
to consider the enormous volumetric expansion as distinguished from
mere lateral extension, resulting from the heating of the moon's crust
to considerable depths. On a very moderate computation, the surface
of the central region of the full moon must at that time rise above
its mean position to such a degree that hundreds, if not thousands,
of cubic miles of the moon's volume lie above the mean position of
the surface there. At new moon--that is, at lunar midnight for the
same region--the same enormous quantity of matter is correspondingly
depressed. And though the actual range in vertical height at any given
point may be small, we cannot doubt that the total effect produced
by these constant oscillations is considerable. Years or centuries
may pass without any great or sudden change, but from time to time
such catastrophes must surely occur. I believe that all the cases of
supposed change in the moon, if all were regarded as proved, could be
thus fully accounted for without any occasion to assume the action of
volcanic forces properly so called.
Before considering the evidence for the new lunar volcano to which Dr.
Klein has recently called the attention of astronomers, it may be well
briefly to describe the condition of the moon's surface.
This surface, which is equal in extent to about that of the American
Continent, or to Europe and Africa together (without their islands),
is divided into two chief portions--the higher levels, which are in
the main of lighter tint, and the lower levels, which are, almost
without exception, dark. It may be remarked in passing that very
erroneous ideas are commonly entertained respecting the moon's general
colour. The moon is very far from being white, as many suppose. On the
contrary, she is far more nearly black than white. It has been well
remarked by Tyndall that if the moon were covered with black velvet
(14,600,000 square miles of that material would be required for the
purpose), she would still appear white to us, for we should see her
disc projected on the blackness of star-strewn space. The actual tint
of the moon as a whole is nearly the same as that of gray weathered
sandstone. The brightest parts, however, are much whiter; Zöllner
infers from his photometric experiments that they can be compared with
the whitest of terrestrial substances. On the other hand, the darkest
parts of the moon are probably far darker than porphyry, even if they
are not so dark that on earth we should call them black. The fact
that the low-lying parts of the moon are much darker than the higher
regions is full of meaning, though hitherto its significance does not
seem to have been much noticed. Either we must assume that these lower
regions, the so-called seas (certainly now dry), are old sea bottoms,
and owe their darkness to the quality of the matter deposited there
in remote ages, or else we must suppose that the matter which last
remained fluid when the moon's surface was consolidating was of darker
material than the rest. For such matter would occupy the lowest lunar
regions. There is here room for a very profitable study of the moon's
aspect by geologists. I doubt not that, however different the general
past history of our earth may have been from the moon's, terrestrial
regions exist where the characteristic features of the moon's surface
are more or less closely illustrated. On the American continent, for
example, there are peculiarities of geological formation which seem
to correspond closely with some of the features of the lunar globe,
presently to be noticed; and it seems to me not improbable that
geologists might find in the study of certain regions in North America
the means of interpreting the difference of tint between higher and
lower levels on the moon. If so, light would probably be thrown on very
difficult questions relating to the remote past, not only of the moon,
but of our own earth.
The lunar feature which comes next in importance to the difference
of tint between the so-called 'seas' and the higher lands is the
existence of remarkable series of radiating streaks extending from
certain important craters--centres probably of past disturbance. It
is impossible to contemplate the disc of the full moon, as seen with
a powerful telescope, without feeling that these systems of rays must
have resulted from the operation of forces of the most stupendous
nature, though as yet their true meaning is hid from us. They would be
marvellous phenomena, even if they were not so mysterious--marvellous
in their enormous extension, their singular brightness, and
their manner of traversing 'seas,' craters, and mountain-ranges
indifferently. But their chief marvel resides in the mysterious manner
of their appearance as the moon approaches her full illumination.
Other lunar features are most clearly recognised when the moon is not
full, for then the shadows which afford our only means of estimating
the height of lunar irregularities are clearly seen along the border
between the bright and dark parts of her face, and we have only to
wait until this border passes over any object we wish to study to
obtain satisfactory evidence of its nature. It is quite otherwise with
the rays. The regions occupied by these radiating streaks are neither
raised nor depressed in such sort as either to throw shadows or to
lie in shadow when surrounding regions are in sunlight. But when the
moon approaches her full illumination, the radiating regions come into
view, as bright streaks--bright even on the light-tinted lunar uplands.
A mighty system of rays can be seen extending from the great crater
Tycho in all directions. Other systems, scarcely less wonderful, extend
from the battlemented crater, Copernicus, the brilliant Aristarchus,
and the solitary Kepler. One ray from Tycho can be traced round nearly
an entire hemisphere of the moon's surface. It is specially noteworthy
of this great ray that, where it crosses the lunar Sea of Serenity,
that great plain seems to be divided as by a sort of ridge line, the
slope of the plain from either side of the ray's track being clearly
discernible when the moon is near her first quarter.
What are these mysterious ray systems? How are we to explain the
circumstance that though only the most tremendous forces seem competent
to account for bands such as these, many miles broad and many hundreds
of miles in length, there are yet none of the usual signs of the action
of volcanic forces? If mighty rifts had been formed in the moon's crust
by the outbursting action of a hot nucleus, or through the contraction
of the crust on an unyielding nucleus (for the effect would be the same
in either case), we should scarcely expect to find that after such
rifts had formed no signs of any difference of level would appear. If
lava flowed out all along the rift, one would imagine that it would
form a long dyke which would throw an obvious shadow, except under full
solar illumination. If the rift were not filled with lava, the bottom
of the rift would certainly remain in shadow long after the surrounding
region was illuminated. That lava should exactly fill the rift along
its entire length seems incredible. This might happen by a strange
chance in the case of a single rift, but not with all the rifts of a
radiating system, still less with all the rifts of all the radiating
systems. Yet I believe that neither astronomers nor geologists can form
any other opinion respecting these mysterious ray-systems than that
they were caused by what Humboldt (speaking of the earth) calls the
reaction of the interior on the crust. Nasmyth has admirably indicated
their appearance, or rather their radiating form, by filling a globular
glass shell with water, hermetically closed, and then freezing the
water. The expansion of the water bursts the glass shell, and the lines
of fracture are found to extend in a series of rays from the part of
the shell which first gave way. But this experiment of itself does not
explain the mystery of the lunar rays. Accepting the theory that the
moon's crust yielded in some such way, we have still to explain how
the rifts which were thus formed came to be covered over with matter
lying nearly at the same level as the surrounding surface. It appears
to me that the only available way of explaining this is somewhat as
follows. First, from the way in which the streaks are covered like the
surrounding region with craters, we may conclude that the streaks are
older than any except the largest craters; from the great extension
of many of them, we may safely infer that the lunar crust possessed a
large measure of plasticity when they were formed (for otherwise it
would have yielded over a smaller area). It was, therefore, probably
still hot during the era (which may have lasted millions of years) to
which the formation of the rifts belonged: accordingly the lava which
flowed out through the rifts remained liquid for a considerable time,
and was thus able to spread widely on either side of the rift, forming
a broad band of lava-covered surface, instead of a steep and narrow
dyke. This seems not only to account for the most striking peculiarity
of the bands, but to accord well with all that is known about them,
and even to suggest explanations of some other lunar features which
had appeared perplexing. I understand that in certain regions of North
America there are lava-covered rifts large enough to form geographical
features, and, therefore, fairly comparable with the lunar radiating
streaks. But as yet American geologists have not presented in an
accessible form a description of the peculiar features of the American
continent; in fact, it may be doubted whether as yet the materials for
such a description exist.
The mountain-ranges of the moon do not differ to any marked degree
from those of our own earth. They are few in number; in fact,
mountain-ranges form a less important feature of lunar than of
terrestrial geography. On the other hand, the lunar ring-mountains and
craters far exceed those of our earth in size and importance. The large
craters may, in fact, be regarded as characteristic features of lunar
scenery. There are several craters exceeding 100 miles in diameter. It
is strange to consider that though the ringed wall surrounding some of
these larger craters exceeds 10,000 feet in height, no trace of the
highest peaks of such a wall would be visible from the middle of the
enclosed plain. Conversely, an observer standing on one of the highest
peaks beside one of these great craters, would not see half the floor
of the crater, while more than half the horizon line around him would
belong to the enclosed plain, and would appear as level as the horizon
seen from a height overlooking a great prairie. These ringed plains
and larger craters seem to belong to the third great era of the moon's
history. The bright high regions and dark low levels called seas must
have been formed while the greater part of the crust was intensely
hot. The contraction of the cooling crust on the nucleus, which cooled
far less slowly, led to the formation of the great ray systems. But
though such systems extend from great craters, these craters themselves
probably attained their present form far later. The crust having in
great part cooled, the nucleus began in turn to shrink more quickly
than the crust, having more heat to part with. Thus the crust, closing
in upon the shrinking nucleus, formed the corrugations and wrinkles
which can be seen under telescopic scrutiny in nearly every part of
the visible lunar surface. The process was accompanied necessarily
by the development of great heat--the thermal equivalent of the
mechanical process of contraction. Mallet has shown that the process
of contraction at present occurring in the earth's crust gives rise
to the greater part of the heat to which volcanic phenomena are due.
If this is so in the earth's case at present, how tremendous must have
been the heat evolved by the far more rapid contraction of the moon's
mass in the remote era we are considering, when probably her heat
passed into space unchecked by the action of a dense moisture-laden
atmosphere! We can well understand that enormous volumes of heated gas
would be formed--including steam, for there is good reason to believe
that water is present in large quantities in the moon's interior. The
imprisoned gas would find an outlet at points of least resistance,
the centres, namely, of the great radiating systems of streaks. These
centres would certainly be regions of outlet. But they would not be
sufficient. We can understand then why every ray system extends from
a great crater, though that crater was really formed after the system
of radiating streaks; and we can equally understand why these central
craters are not the only or even the chief of the great craters in the
moon. Here again I would suggest that possibly the careful study of
American geology might disclose features illustrating the great lunar
craters.
When we pass to the smaller craters, ranging in diameter from seven
or eight miles to less than a quarter of a mile, even if there be not
some far smaller and beyond the range of the most powerful telescopes
man can construct, we find ourselves among objects resembling those
with which the study of our own earth has rendered us familiar. When
Sartorius's map of Etna and the surrounding region was first seen at
the Geological Society's rooms, many supposed that it represented
lunar features. The Vesuvian volcanic region, again, is presented
side by side with a lunar region of similar extent in Nasmyth's fine
treatise on the moon, and the resemblance is very close. Considering
the part which water plays in producing terrestrial volcanic phenomena,
it may reasonably be doubted whether there is in reality so close a
resemblance as a superficial comparison (and we can make no other)
would suggest. There are those, indeed, who believe that some of the
multitudinous small craters of the moon have had their origin in the
downfall of meteoric masses on her once plastic surface; and strange
though the thought may seem, there would be considerable difficulty
in showing how the surface of the moon could have remained without
traces of the meteoric downfall to which during myriads of centuries
she was exposed undefended by that atmospheric shield which protects
our earth from millions of meteors yearly falling upon her. We could
only attribute the smallest lunar craters, however, to this cause.
It may be noticed in passing that Professor Newcomb, apparently
referring to this suggestion, which some had thought too fanciful to
be seriously advanced, says that 'the figures of these inequalities
(the small craters) can be closely imitated by throwing pebbles upon
the surface of some smooth plastic mass, as mud or mortar.' Craters,
however, larger than a mile or so in diameter, and many also of smaller
dimensions, must be regarded as due to the same process of contraction
which produced the great craters, but as belonging to an era when this
process went on less actively. In like manner another feature of the
moon's surface, the existence of narrow furrows called _rilles_, which
sometimes extend to a considerable distance, passing across levels,
intersecting crater walls, and reappearing beyond mountain-ranges as
though carried under like tunnels, must be regarded as due to the
cracking of the crust thus slowly shrinking.
It is noteworthy that the signs of change which have been suspected
during recent years belong to these smaller and probably more recent
lunar formations. In November, 1866, Dr. Schmidt, chief of the
Athens Observatory, announced that the crater Linné in the lunar
Sea of Serenity was missing. To understand the importance of this
announcement, let it simply be noted that the quantity of matter
necessary to fill that crater up would be at least equal to that
which would be required to form a mountain covering the whole area
of London to a height of two miles! The crater was described by
former lunar observers as at least five miles in diameter and very
deep. It is not now actually missing, as Schmidt supposed, but it is
certainly no longer deep. It is, in fact, exceedingly shallow. Sir
J. Herschel's opinion was that the crater had been filled up from
beneath by an effusion of viscous lava, which, overflowing the rim on
all sides, poured down the outer slope so as to efface its ruggedness
and convert it into a gradual declivity casting no stray shadows. But
the stupendous nature of the disturbing forces necessary to produce
such an overflow of molten matter has led most astronomers to adopt
in preference the theory that the wall surrounding the crater has
been overthrown, either in consequence solely of the processes of
contraction and expansion described above, or from the reinforcement
of their action by the effects due to sublunarian energies. Some
consider that the descriptions of the crater by Mädler and Lohrmann
(which slightly differ) were erroneous, and that there has been no real
change. Others deny that any change has occurred, on the ground that
Linné varies in aspect according to the manner of its illumination.
This I perceive is Professor Newcomb's explanation, who considers
such variations 'sufficient to account for the supposed change.' But
since the time of Schmidt's announcement Linné has several times been
observed under nearly the same conditions as by Mädler and Lohrmann, as
the great shadows formerly seen in its interior have not reappeared.
There seems to be great reason for believing that a change has really
occurred there.
The discovery announced by Dr. Klein is of a different nature. Near the
middle of the visible half of the moon there is a well-known though
small crater called Hyginus, the neighbourhood of which has been often
and carefully examined. While examining this part of the moon's surface
with an excellent 5-1/2in. telescope, in May, 1877, Dr. Klein observed
a small crater full of shadow, and apparently nearly three miles in
diameter. It formed a conspicuous object on the Sea of Vapours. Having
frequently observed this region during the last few years, he felt
certain that no such crater existed there in 1876. He communicated
his discovery to Dr. Schmidt, who stated, in reply, that in all the
numerous drawings he had made of this lunar region no such crater was
indicated. It is not shown in the great chart by Beer and Mädler, or in
Lohrmann's map. Further observation showed that the crater is a deep,
conical opening in the moon's surface. Soon after the sun has risen
at that part of the moon, and, as later observations confirm, shortly
before sunset there, the opening is entirely in shadow, and appears
black. But when the sun is rather higher it appears grey, and with a
yet higher sun it can no longer be distinguished. It can, however, be
seen when the sun is very high on that part of the moon, appearing then
somewhat brighter than the surrounding region, a circumstance which
does not hitherto seem to have been noticed by either Klein or Schmidt.
The moon's surface has been so long and so carefully studied, that it
is almost impossible to understand how such a crater as now certainly
exists in the Sea of Vapours near Hyginus could have escaped detection.
Craters of the kind exist, indeed, in hundreds on the moon's surface.
But many astronomers have given years of their life to the study of
such objects; and the centre of the moon's disc, for reasons which
astronomers will understand, has been studied with exceptional care.
It seems so unlikely that a deep crater three miles in diameter could
escape recognition, that some astronomers have not hesitated to regard
the newly-detected crater as certainly a new formation. For my own
part, though it seems almost impossible to explain how such a crater
could have remained so long unnoticed, I can regard the evidence of
change as amounting only to extreme probability so far as it depends on
the result of past telescopic scrutiny of the moon.
Admitting that a change had occurred, it would not follow that it had
been produced by volcanic forces. It seems far more likely that a
floor originally covering the conical hole now existing in the Sea
of Vapours has given way at last under the effect of long-continued
processes of expansion and contraction, which would operate with
special energy over a region, like the Sea of Vapours, near the moon's
equator.
But there remains to be mentioned a form of evidence respecting
lunar features which could not be effectively applied to the case
of the crater Linné, because the moon had only been subject to the
necessary method of examination during a few years before that crater
was missed. I refer to lunar photography. Many objects less than two
miles in diameter are shown in the best photographs of our satellite
by Rutherfurd, De la Rue, Ellery, and Draper; and as the moon has been
photographed in every phase, some among the views might fairly be
expected to show Klein's crater if it really existed before 1877. I do
not find that in any lunar photographs the crater is shown as a black
or dark gray spot. But in Rutherfurd's splendid photograph of the moon
on March 6, 1865 (when the moon was about nine days five hours old),
the place of Klein's crater is occupied by a small spot lighter than
the surrounding 'sea.' This is the usual appearance of a small crater
under a high sun; and though it may indicate only the existence of a
flat crater floor in 1865 where now a great conical hole exists, it
throws some degree of doubt on the occurrence of any change at all
there. The case strongly suggests the necessity for continuing the
work of lunar photography, which seems of late years to have flagged.
Photographs of the moon should be taken in every aspect and in every
stage of her librational swayings. Possessing such a series, we should
be able to decide at once whether any newly-recognised crater was in
reality a new formation or not.
_THE NOVEMBER METEORS._
During November 13 and 14 the earth is passing through the region along
which lies the course of the family of meteors called the Leonides,
sometimes familiarly known as the November meteors. When at this time
of the year the meteor region thus traversed by the earth is densely
strewn with meteors, there occurs a display of falling stars, one of
the most beautiful, and, rightly understood, one of the most remarkable
of all celestial phenomena. Of old, indeed, when it was supposed that
these meteors were purely meteorological phenomena, they were not
thought specially interesting objects. They were held by some as mere
weather-portents. It was only when a storm of wind was approaching,
_vento impendente_, according to Virgil, that a shower of meteors was
to be seen. Gross ignorance, indeed, has given to showers of falling
stars an interest surpassing even that which has become attached to
them through the discoveries of modern science, for they have been
regarded as portending the end of the world. The shower of November
13, 1833, which was seen in great splendour in America, frightened the
negroes of the Southern States nearly out of their wits. A planter
of South Carolina relates that he was awakened by shrieks of horror
and cries for mercy from 600 or 700 negroes. When he went out to see
what was the matter, he found the negroes prostrate on the ground,
'some speechless, some with bitterest cries imploring God to spare the
world and them.' There is, however, a grandeur in the interpretation
placed by modern science upon these beautiful displays which dwarfs
into littleness even such ideas as have been suggested by the terrors
of superstition. We perceive that meteors are not mere terrestrial
phenomena, nor of brief existence. They speak to us of domains in space
compared with which the volume of our earth--nay, even the volume of
the sun himself--is a mere point: of time-intervals compared with
which the millions of years spoken of by geologists appear but as mere
seconds.
The special meteor family whose track the earth crosses on November
13-14 forms a mighty ellipse round the sun, extending more than 19
times farther from him than the track of our earth, which yet, as
we know, lies more than 92,000,000 miles from the sun. Along this
tremendous orbit the meteors speed with planetary but varying velocity,
crossing the track of our earth with a velocity exceeding by more than
a third her own swift motion of about 19 miles in every second of time.
Coming down somewhat aslant, but otherwise meeting the earth almost
full tilt, the meteors rush into our air at the rate of more than 40
miles per second. They are so intensely heated as they rush through
it that they are turned into the form of vapour, insomuch that we
never make acquaintance with the members of this particular meteoric
family in the solid form. In this respect they resemble the greater
number of our meteoric visitants. It is, indeed, a somewhat fortunate
circumstance for us that this is so, for if Professor Newton, of Yale
College (United States), is right in estimating the total number of
meteors, large and small, which the earth encounters per annum at
400,000,000, it would be rather a serious matter if all or most of
these bodies were not warded off. The least of them, even though a mere
grain perhaps in weight, would yet, arriving with planetary velocity
exceeding a hundredfold or more the velocity of a cannon-ball, prove
an awkward missile if it struck man or animal. But the air effectually
saves us from all save a few fire-balls which are large enough to
remain in great part solid until they actually strike the earth itself.
The importance of the meteors in the planetary system will be
recognised when we remember that the November group alone extends along
its oval course in one complete system of meteors for a length of more
than 1,700 millions of miles, with an average thickness of about a
million miles (determined by noting the average time occupied by the
earth in passing through the system on November 13-14), and an unknown
cross breadth which probably does not fall short of three or four
millions of miles. Other systems are, no doubt, far more important,
for it has been found that meteors follow in the track of comets. Now
the November meteors follow in the track of a comet (Tempel's comet of
1866), which was so small when last favourably placed for observation
that it escaped detection by the naked eye. If so small a comet as
this is followed by so large a meteoric system, in which also meteors
are strewn so richly that during the passage of the earth through it,
tens of thousands of meteors have been counted, how vast must be the
numbers and how large probably the individual bodies following in the
track of such splendid comets as Newton's, Donati's (1858), the comets
of 1811, 1847, 1861, and others! For it should be remembered that we
become cognisant of the existence of a meteoric system only when the
earth threads its way through one, when those which she encounters may
become visible as falling stars if it so chances that she encounters
them on the dark or night half of her surface. But the earth is far
smaller compared with a system like the November meteor-flight than a
rifle-ball compared with the largest flight of birds ever yet seen.
Such a ball fired into a very dense and widely extending flock of
birds might encounter here and there along its course some five or six
birds--not one in 10,000, perhaps, of the entire flight; and if the
flock continued flying with unchanging course, a hundred rifle balls
might be fired through it without seemingly reducing its numbers.
Our earth has passed hundreds of times through the November meteor
system, yet its meteoric wealth has scarcely been reduced at all, so
exceedingly minute is the track of the earth through the meteor system
compared with the extension of the system itself. The region through
which the earth has passed is less than a billionth part of the entire
region occupied by the system. But the November system is but one among
several hundreds through which the earth passes--in other words, the
systems which chance to be traversed by that mere thread-like ring in
space traversed each year by the earth, are not a millionth, not a
billionth, of the total number of such systems. It will be conceived,
therefore, that the total amount of meteoric matter, travelling on
orbits of all degrees of eccentricity and extension from the sun and
inclined at all angles to the general plane of the solar system, must
be enormously great. The idea once advanced by an eminent astronomer
that the total quantity of unattached matter, so to speak, existing
within the solar domain must be estimated rather by pounds than by tons
is now altogether exploded. It would be truer to say that the totality
of matter thus freely travelling around the sun must be estimated by
billions of tons rather than by millions.
Whether it is likely that there will be a display of meteors to-night
(or, rather, to-morrow morning), is a question to which most
astronomers would be disposed, we believe, to reply definitely in the
negative. The display of November 13-14, 1866, was very brilliant; that
of 1867 (best seen in the United States) was almost equally so; but
successive showers steadily diminished. In other words, the part of the
system crossed by the earth in 1866 and 1867 was very rich, but the
part which she crossed afterwards (the rich part having passed far on
towards the remote aphelion of the system outside the orbit of Uranus)
was less rich. For the last few years very few November meteors have
been seen, though the few stragglers which have been seen, and have
been identified as belonging to the family by their paths athwart
the star-depths, have been almost as interesting to astronomers as
the showers of such bodies seen in 1799, 1833, 1866, and 1867. But it
is not altogether impossible that in the small hours 'ayont the twal'
to-morrow morning a shower of meteors may be seen. For Schiaparelli
(the Italian astronomer who first started the ideas which led when
properly followed up to the discovery of the relations existing
between meteors and comets) asserts that it has happened before now
that the November meteors have appeared in great numbers in years
lying midway between the times of _maximum_ display. These times are
separated on the average by about 33-1/4 years. Thus, in 1799, there
was a great display of November meteors, a shower rendered specially
celebrated by Humboldt's description. In 1833 there was another, the
display which so terrified the negroes of South Carolina, but more
interesting scientifically as described by Arago. In 1866 the shower
again attained its _maximum_ splendour, though the display of 1867 was
little inferior. It will not be till 1899 that another great shower of
November meteors may be confidently looked for. But if Schiaparelli
be right, it is quite possible that there may be a shower this year,
due to some scattered flight of the November meteors which, delayed
accidentally (through some special perturbation) many hundreds of years
ago, has come in the course of ages to travel nearly half a circuit
behind the richest part of the system, the 'gem of the meteor-ring,'
as it has been poetically called. Even, however, though no display of
November meteors should be seen, yet the recognition of even a few
scattered stragglers would be exceedingly interesting to astronomers.
A single meteor seen to-night which could be regarded as certainly
belonging to the November system would suffice to show the possibility
that a whole flight of the November meteors might travel at a similar
distance behind the main body. It would be more easy, however, to
identify two such meteors than one, six than two, and a score than
half-a-dozen. The only way in which a meteor can be questioned, so to
speak, respecting the family it belongs to, is by noting its path
across the sky. If this path tends directly from the constellation
Leo (however remote Leo may be from the part of the heavens traversed
by the meteor), the chances are that the meteor is a Leonid, or one
of the November family. If the path tends from that particular part
of the constellation Leo (near the end of the curved blade of the
so-called Sickle in Leo), the probability of the meteor being a Leonid
is increased. If two or more meteors are seen to-morrow morning (after
12.30) which both tend from the Sickle in Leo, even though they seem to
tend in opposite directions, the chances are yet greater that they are
travelling in parallel paths along the track of the November meteors,
but some 2,000 million miles behind the main body. Should the number
mount up to a score or so, the conclusion would be, to all intents and
purposes, certain; and the possible occurrence of even a shower of
Leonids at a time midway between the customary _maxima_ of the meteoric
displays would be placed beyond question.
We must, however, admit that it seems less likely there will be
anything like a display of Leonids to-night than that patient observers
may be able to identify a few of these bodies, and thus--though by
observations of a less attractive kind--to advance our knowledge of
this interesting system. Far more likely is it that towards the end
of the month there will be a display of meteors belonging to another
and an entirely distinct family, a family scarcely less worthy to be
called November meteors _par excellence_, but actually rejoicing in the
classically unsatisfactory name of Andromeds.
_EXPECTED METEOR SHOWER._
(From the _Times_ of November 25, 1878.)
It is probable that during the next three nights some light may be
thrown on one of the most perplexing yet most interesting of all
the problems recently suggested to the study of astronomers. It is
confidently expected that many of those November meteors called
Andromeds will be seen on one or other of those nights, if not on all
three. No meteor systems, not even the famous systems of August and
November, are more remarkable than this singular family. To explain
why astronomers regard the Andromeds with so much interest, it will
be necessary to speak of an object which at first sight seems in no
way connected with them--an object, in fact, which, so long as it was
actually known to astronomers, was never supposed to be connected with
any family of meteors--the celebrated lost comet called Biela's (or, by
Frenchmen, Gambart's comet). In February, 1826, Biela discovered in the
constellation Aries a comet which was found to be travelling in an oval
path round the sun, in a period of about six years seven and a half
months. Tracing its course backwards, astronomers found that it had
been seen in 1772 by Montaigne, and observed for two or three weeks in
that year by Messier, the great comet hunter. Nothing very remarkable
was recognised regarding this comet in 1826, except the fact that its
path nearly intersects that of our own earth; so that if ever the earth
is to encounter a comet, here seemed to be the comet she had to fear.
Great terror was, indeed, excited by the announcement that in 1832 the
comet would cross the earth's track only four or five weeks before the
earth came to the place of danger. But no harm happened. In that year,
and again in 1839, the comet returned quietly enough, though in 1839
it was not observed, being so placed that it was lost in the splendour
of the solar rays. In February, 1846, the comet was again seen, this
being the third return since its discovery in 1826, or rather, since
its recognition as a member of the solar system, the eleventh since it
was first seen by Montaigne. At this time everything seemed to suggest
that this comet, unless our earth at some future time should absorb it,
would remain for a long time a steady member of the sun's comet family.
But only a few days after its detection in February, 1846, the comet
was found to have divided into two, which travelled side by side until
both vanished from view with increasing distance. In 1852 the companion
comets reappeared, and again both continued in view till their motion
carried them beyond telescopic range. As the distance between the
coupled comets had increased from about 160,000 miles in 1846 to about
1,250,000 miles in 1852, astronomers anticipated a most interesting
series of observations at the successive returns of the double comet to
the earth's neighbourhood. Unfortunately, in 1859 the comet's course
carried it athwart a part of the sky illuminated by the sun's rays, so
that astronomers could not then expect to see it. But in 1866 it was
looked for hopefully. Its orbit had now been most carefully computed,
and many observers, armed with excellent telescopes, were on the watch
for it, with very accurate knowledge of the course along which it
might be expected to travel, and even of its position from day to day
and from hour to hour. But it was not seen. Nor, again, was it seen
in 1872, when fresh computations had been made, and observations were
extended over a wider range, to make sure, as was hopefully thought,
that this time it should not escape recognition. Could it have come,
asked Herschel in 1866--and in 1872 the same question might still
more pertinently be asked--into contact or exceedingly close approach
to some asteroid as yet undiscovered? or, peradventure, had it
plunged into and got bewildered among the rings of meteorolites, which
astronomers more than suspected?
Between 1866, when Sir John Herschel thus wrote, and 1872, when again
Biela's comet was sought in vain, a series of strange discoveries had
been made respecting meteors, which led astronomers to believe that,
even though the missing comet might never again be seen as a comet,
we might still learn something respecting its present condition.
It had been noticed that the remarkable comet of 1862 (comet 11 of
that year) crossed the earth's track near the place where she is on
August 10-11, the time of the August meteors, called the Tears of St.
Lawrence in old times, but now known as the Perseids, because they seem
to radiate from the constellation Perseus. Later the idea occurred
to Schiaparelli, an Italian astronomer, that the August meteors may
travel along the path of that comet. He could not prove this, but he
advanced very strong evidence in favour of the opinion, for he found
that bodies travelling along the path of the comet of 1862 would seem
to radiate from Perseus as they traversed the earth's atmosphere. It
was as if a person suspected that a steam-cloud seen on a distant
railway track belonged to a particular train, and, though unable
actually to prove this, was yet able to show that, with the wind and
weather then prevailing, that train, travelling at its customary rate,
would leave a steam-cloud behind it precisely of the apparent length
and position of the observed steam-cloud. This cloud might have the
observed position though otherwise produced, yet the evidence would be
thought strongly to favour the supposition that it came from the train
in question. In like manner the August meteors might be travelling on
any one of a great number of tracks intersecting the earth's orbit in
the place occupied by the earth on August 10-11; yet it was at least a
striking coincidence that a flight of meteors travelling in the orbit
of the chief comet of 1862 would seem to radiate from the constellation
Perseus, precisely as the August meteors do.
While astronomers were still discussing the ideas of Schiaparelli,
Professor Newton of Yale College, in America, called their attention
to the great display of November meteors which might be expected on
November 13-14, 1866. The fine shower of that year was well observed,
and the part--we may almost say the point--of the constellation Leo
from which the meteors radiated was correctly determined. And now a
strange thing happened. Those who believed in Schiaparelli's account of
the August meteors supposed of necessity that the bodies forming that
system travel in an orbit of enormous extent, for the comet of 1862
travels on a path extending much further from the sun than the path of
Neptune. There was, therefore, nothing to prevent them from believing
that the Leonides travel in a track carrying them far away from the
sun. The recurrence of great displays of these meteors at intervals of
about 33 years might be readily explained on such an assumption, for if
the Leonides have a period of about 33 years, their path must extend
far beyond the path of Uranus. But hitherto astronomers had not been
ready to admit such an explanation of the periodic recurrence of great
displays of the November meteors. They preferred theories (for several
were available) which accounted for the 33-year period, while assigning
to the Leonides paths of much less extent. Now that the idea of vast
meteoric orbits had been fairly broached, some astronomers thought it
might at least be worth while to calculate the path of the November
meteors on the assumption that their true period is about 33-1/4 years.
This was perfectly easy, because the period of a body travelling round
the sun determines the velocity at any given distance from the sun,
and knowing thus (at least, on this assumption) the true velocity of
the Leonides as they rush into our air, while their apparent path is
known, their true course is as readily determined as the true course
of the wind can be determined by a seaman from the apparent direction
and velocity with which it reaches his ship. When the path of the
November meteors had been determined (on the assumption mentioned),
it was found to be identical with the path of a comet which had only
been discovered a few months before-the comet called Tempel's. That a
comet which is invisible to the naked eye should have been discovered
in the very year when first astronomers made exact observations of the
meteors which travel in its track--for it will presently be seen that
the assumption above mentioned was a just one--cannot but be regarded
as a very singular coincidence. It was a most fortunate coincidence
for astronomers, since there can be but little doubt that but for it
Schiaparelli's theory would very soon have been forgotten. As that
theory was itself suggested by the fortuitous recognition of another
comet (only visible at intervals of more than a century) at a time when
attention had been specially directed to the August meteors, it may
fairly be said that the theory which now associates meteors and comets
in the most unmistakable manner was suggested by one accident and
confirmed by another. Albeit such accidents happen only to the zealous
student of nature's secrets. We shall presently see that the fortunate
detection of Tempel's comet in 1866 was not the last of the series of
coincidences by which the theory of meteors was established.
Although the evidence favouring Schiaparelli's theory was now strong,
yet it was well that at this stage still more convincing evidence
was forthcoming. The date of the November display has changed since
the Leonides were first recognised, in such sort as to show that the
position of their path has changed. The change is due to the disturbing
attractions of the planets. It occurred to our great astronomer Adams,
discoverer with Leverrier of distant Neptune, to inquire whether the
observed change accorded with the calculated effects of planetary
attraction, if the Leonides are supposed to travel in any of the
smaller paths suggested by astronomers, or could be explained only by
the assumption that the meteors travel on the widely-extending path
corresponding to the 33-1/4 years period. The problem was worthy of
his powers--in other words, it was a problem of exceeding difficulty.
By solving it, Adams made that certain which Schiaparelli and his
followers had merely assumed. He showed beyond all possibility of
doubt or question that of all the paths by which the periodic meteoric
displays could be accounted for, the wide path carrying the November
meteors far beyond the track of Uranus was the only one which accorded
with the observed effects of planetary perturbation.
It was in the confidence resulting from this masterly achievement that
in 1872 some astronomers (among them Professor Alex. Herschel, one of
Sir J. Herschel's sons) announced the probable occurrence of a display
of meteors when the earth crossed the track of Biela's missing comet.
An occurrence of this sort was alone wanting to complete the evidence
for the meteoric theory. It had been found that the August Perseids
move as if they followed in the track of a known comet; the path of the
November Leonides had been shown to be identical with that of another
comet; if astronomers could predict the appearance of meteors at the
time when the earth should pass through the track of a known comet,
even those who could not appreciate the force of the mathematical
evidence for the new theory would be convinced by the meteoric display.
Possibly such observers would have been satisfied with a meteor shower
which would not have contented astronomers. The display must have
special characteristics to satisfy scientific observers. The path of a
body following Biela's comet being known, and its exact rate of motion,
the direction in which it must enter our earth's atmosphere (if at
all) is determined. Calculation showed this direction to be such that
every meteor would appear to travel directly from the constellation
Andromeda,--from a point near the feet of the Chained Lady. A meteor
might appear in any part of the sky, but its course must be directed
from that point, otherwise it could not possibly be travelling in the
track of Biela's comet.
The event corresponded exactly with the anticipations of astronomers.
On the evening of November 27, 1872, many thousands of small meteors
were seen. In England between 40,000 and 50,000 were counted. In Italy
the meteors were so numerous that at one time there seemed to be a
cloud of light around the region near the feet of Andromeda whence all
the meteor-tracks seemed to radiate. The meteors were unmistakably
travelling on the track of Biela's comet. They overtook the earth on
a path slanting downwards somewhat from the north--precisely in the
direction in which Biela's comet would itself have descended upon the
earth if at any time the earth had chanced to reach the part of her
path crossed by the comet's when the comet was passing that way.
Strangely enough, a German astronomer, Klinkerfues, seems to have
regarded the meteoric display of November 27, 1872, as an actual visit
from Biela's comet. He telegraphed to Pogson, Government Astronomer
at Madras, 'Biela touched earth on November 27, look out for it near
Theta Centauri;' which, being interpreted, means, Biela's comet then
grazed the earth, coming from the feet of Andromeda, look for it where
it is travelling onwards in the opposite direction--that is towards the
shoulder of the Centaur. As Biela's comet had in reality passed that
way twelve weeks earlier, the instructions of Klinkerfues were somewhat
wide of the mark. However, Pogson followed them, and near the spot
indicated he saw two faint cloud-like objects, slowly moving athwart
the heavens. These he supposed to be the two comets into which the
missing comet had divided. It so happens, strangely enough, that these
objects, though moving parallel to the track of the missing comets,
were neither those comets themselves, nor the meteor flight through
which the earth had passed a few hours before. They were probably
somewhat richer meteor clouds, fragments (like the cloud through which
our earth had passed) of this most mysterious of all known comets.
To-night, or perhaps to-morrow or next night (for the position of the
meteor flights is not certainly known) we shall probably see meteors
travelling in advance of the main body. For the earth passes during
the next three days across the orbit of Biela's comet, about as far
in front of the head as she passed behind the head in 1872. Now,
there is no known reason for supposing (on _à priori_ grounds) that
meteors get strewn behind a comet's nucleus more readily than in front
of it. The disturbing forces which would tend to delay some meteoric
attendants would be balanced by forces which would tend to hasten
others. As a matter of fact it would seem that the meteor flights
which follow a comet's nucleus are commonly denser than those which
precede the nucleus. Yet in 1865 many thousands of Leonides were seen
which were in advance of the main body forming the comet of 1866. In
1859, 1860, and 1861, many Perseids were seen, which were in advance
of the comet of 1862. So that we might fairly expect to see a great
number of Andromeds to-night (or on the following nights) even if we
had none but the probabilities thus suggested to guide us. But since
many were seen on November 27 last, when the head of the comet, now
some four months' journey from us, was a whole year's journey further
away, it seems probable that on the present occasion a display well
worth observing will be seen should fine weather prevail. It will be
specially interesting to astronomers, as showing how meteors are strewn
in front of a comet. How meteors are strewn behind a comet we already
know tolerably well from observations made on the Perseids since 1862
and on the Leonides since 1865.
_COLD WINTERS._
During the cold weather of last December (1878) we heard much about
old-fashioned winters. It was generally assumed that some thirty or
forty years ago the winters were colder than they now are. Some began
to speculate on the probability that we may be about to have a cycle
of cold winters, continuing perhaps for thirty or forty years, as the
cycle of mild winters is commonly supposed to have done. If any doubts
were expressed as to the greater severity of winter weather thirty
or forty years ago, evidence was forthcoming to show that at that
time our smaller rivers were commonly frozen over during the winter,
and the larger rivers always encumbered with masses of ice, and not
unfrequently frozen from source to estuary. Skating was spoken of as a
half-forgotten pastime in these days, as compared with what it was when
the seniors of our time were lads. Nor were dismal stories wanting of
villages snowed up for months, of men and women who had been lost amid
snowdrifts, and of other troubles such as we now associate rather with
Siberian than with British winters.
Turning over recently the volume of the 'Penny Magazine' for the year
1837, I came across a passage which shows that these ideas about
winter weather forty years ago were entertained forty years ago about
winter weather eighty or ninety years ago. It occurs in an article on
the 'Peculiarities of the Climate of Canada and the United States.'
Discussing the theory whether the clearing away of forests has any
influence in mitigating the severity of winter weather, the writer
of the article says, 'Many persons assert, and I believe with some
degree of accuracy, that the seasons in Europe, and in our own island
particularly, have undergone a remarkable change within the memory
of many persons now living; and if such really be the case, how few
attempts have been made to account for this change, since no great
natural phenomenon, like that of clearing away millions of acres of
forest timber, and thereby exposing the cold and moist soil to the
action of the sun's rays, has recently taken place here; so that if the
climate of Great Britain has actually undergone a change, the cause,
whatever that may be, must be of a different nature from that generally
supposed to affect the climate of North America.' It must be explained
that, though in this passage the writer does not speak of a diminution
in the severity of the winters, it is a change of that sort that he is
really referring to. He had said, a few lines before, that 'some of
the older inhabitants of North America will declare to you that the
winters are much less severe "now" than they were forty or fifty years
ago,' and in the passage quoted he is discussing the possibility of a
similar change in Europe, where, however, as he points out, the cause
assigned to the supposed change in America has certainly no existence.
Since 1830, by the way, the theory has been advanced that the supposed
mildness of recent winters may have been caused by the large increase
in the consumption of coal, owing to the use of steam machinery, gas
for lighting purposes, and so forth.
I believe it will be found on careful inquiry that the change for
which forty years ago men sought a cause in vain, and for which at
present they assign a perfectly inadequate cause, has had no real
existence. The study of meteorological records gives no valid support
to the theory of change. Nor is it difficult to understand how the idea
that there has been a change has arisen from the changed conditions
under which men in middle life, as compared with children, observe
or feel the effects of milder weather. A child gives no heed to mild
winters. They pass, like ordinary spring or autumn days, unnoted and
unremembered. But a bitter winter, or even a spell of bitter weather
such as is felt almost every year, is remembered. Even though it lasts
but for a short time, it produces as much effect on the childish
imagination as a long and bitter winter produces on the minds of grown
folk. Looking back at the days of childhood, the middle-aged man or
woman recalls what seems like a series of bitter winters, because
recalling many occasions when, during what seemed a long time, the snow
lay deep, the waters were frozen, and the outdoor air was shrewd and
biting.
Before considering some of the remarkable winters which during the last
century have been experienced in Great Britain and in Europe generally,
I would discuss briefly the evidence on which I base the belief that
the winter weather of Europe, and of Great Britain especially, has
undergone no noteworthy change during the last century.
If there is any validity in the theory at present in vogue that our
winters are milder now than they were forty or fifty years ago, and
the theory in vogue as we have seen forty years ago that the winters
then were milder than they had been forty or fifty years earlier, it is
manifest that there ought to be a very remarkable contrast between our
present winter weather and that which was commonly experienced eighty
or ninety years since. Now, it so chances that we possess a record of
the weather from 1768 to 1792, by a very competent observer--Gilbert
White of Selborne--which serves to show what weather prevailed
generally during that interval; while the same writer has described
at length, in his own happy and effective manner, some of the winters
which were specially remarkable for severity. Let us see whether the
winters during the last third of the eighteenth century were so much
more bitter or long-lasting than those now experienced as common ideas
on the subject would suggest.
In 1768, the year began with a fortnight's frost and snow. The cold was
very severe, as will presently be more particularly noted. Thereafter
wet and rainy weather prevailed to the end of February. The winter of
1768-69 was marked throughout by alternations of rain and frost; thus
from the middle of November to the end of 1768 there were 'alternate
rains and frosts;' in January and February, 1769, the weather was
'frosty and rainy, with gleams of fine weather in the intervals; then
to the middle of March, wind and rain.' The last half of November,
1769, was dry and frosty, December windy, with rain and intervals of
frost, and the first fortnight very foggy; the first fortnight of
January, 1770, frosty, but on the 14th and 15th all the snow melted
and to the end of February mild hazy weather prevailed; March was
frosty and bright. From the middle of October, 1770, to the end of the
year, there were almost incessant rains; then severe frosts till the
last week of January, 1771, after which rain and snow prevailed for a
fortnight, followed by spring weather till the end of February. March
and April were frosty. The spring of 1771 was so exceptionally severe
in the Isle of Skye that it was called the Black Spring; in the south
also it was severe. November, 1771, frost with intervals of fog and
rain; December, mild and bright weather with hoar frosts; January and
the first week of February, 1772, frost and snow; thence to the end of
the first fortnight in March, frost, sleet, rain, and snow.
The winter of 1772-73 would fairly compare with the mildest in recent
years, except for one fortnight of hard frost in February, 1773. For
from the end of September to December 22 there were rain and mild
weather--the first ice on December 23--but thence to the end of the
month foggy weather. The first week in January, frost, but the rest of
the month dark rainy weather; and after the fortnight of hard frost in
February, misty showery weather to the end of the first week in March,
and bright spring days till April.
There were four weeks of frost after the end of the first fortnight in
November, 1773, then rain to the end of the year, and rain and frost
alternately to the middle of March, 1774.
In 1774-1775 there seems to have been no winter at all worth
mentioning. From August 24 to the end of the third week in November
there was rain, with frequent intervals of sunny weather. Then to the
end of December, dark dripping fogs. January, February, and the first
half of March, 1775, rain almost every day; and to the end of the first
week in April, cold winds, with showers of rain and snow.
The end of the year 1775 was rainy, with intervals of hoar frost and
sunshine. Dark frosty weather prevailed during the first three weeks of
January, 1776, with much snow. Afterwards foggy weather and hoar frost.
The cold of January, 1776, was remarkable, and will presently be more
fully described.
November and December, 1776, were dry and frosty, with some days of
hard rain. Then to January 10, 1777, hard frost; to the 20th foggy
with frequent showers; and to February 18, hard dry frost with snow,
followed by heavy rains, with intervals of warm dry spring weather to
the end of May.
The winter of 1777-78 was another which resembled closely enough those
winters which many suppose to be peculiar to recent years. The autumn
weather to October 12 had been remarkably fine and warm. From then to
the end of the year, grey mild weather prevailed, with but little rain
and still less frost. During the first thirteen days of January there
was frost with a little snow; then rain to January 24, followed by six
days of hard frost. After this, harsh foggy weather with rain prevailed
till February 23; then five days of frost; a fortnight of dark harsh
weather; and spring weather to the end of the first fortnight in April.
The second fortnight of April, however, was cold, with snow and frost.
Similarly varied in character was the winter of 1778-79. From the end
of September, 1778, to the end of the year the weather was wet, with
considerable intervals of sunshine. January, 1779, was characterised by
alternations of frost and showers. After this, to April 21, warm dry
weather prevailed.
The winter of 1779-80 was rather more severe. During October and
November the weather was fine with intervals of rain. December rainy,
with frost and snow occasionally. January 1780, frosty. During February
dark harsh weather prevailed, with frequent intervals of frost. March
was characterised by warm, showery, spring weather.
November and December, 1781, were warm and rainy; and the same mild
open weather prevailed till February 4. Then followed eighteen days of
hard frost, after which to the end of March the weather was cold and
windy, with frost, snow, and rain. Thus the first two-thirds of the
winter of 1781-82 were exceptionally mild, while the last third was
cold and bleak.
In November, 1782, we find for the first time in these records an
instance of early and long-continued cold. 'November began with a hard
frost, and continued throughout, with alternate frost and thaw. The
first part of December frosty.' The latter half of December, however,
and the first sixteen days of January were mild, with much rain and
wind. Then came a week of hard frost, followed by stormy dripping
weather to the end of February. Thence to May 9, cold harsh winds
prevailed. On May 5 there was thick ice.
The next two winters were, on the whole, the severest of the entire
series recorded by Gilbert White, though at no time in the winter of
1783-84 was the cold greater than has often been experienced in this
country. White's record runs thus: From September 23 to November 12,
dry mild weather. To December 18, grey soft weather with a few showers.
Thence to February 19, 1784, hard frost, with two thaws, one on January
14, the other on February 5. To February 28, mild wet fogs. To March 3,
frost with ice. To March 10, sleet and snow. To April 2, snow with hard
frost.
The winter of 1784-85 was remarkable for the exceedingly severe
cold of December, 1784, which will presently be referred to more
particularly. From November 6 to the end of the year 1784, fog, rain,
and hard frost alternated, the frost continuing longest and being
severest in December. On January 2 a thaw began, and rainy weather with
wind continued to January 28. Thence to March 15 hard frost; to March
21 mild weather with sprinkling showers; to April 7 hard frost.
After rainy weather till December 23, 1786, came frost and snow till
January 7, 1787. Then a week of mild and very rainy weather, followed
by a week of heavy snow. From January 21 to February 11, mild weather
with frequent rains; to February 21 dry weather with high winds; and to
March 10, hard frost. Then alternate rains and frosts to April 13.
Early in November, 1786, there was frost, but thence to December 16
rain with only 'a few detached days of frost.' After a fortnight of
frost and snow, came 24 days of dark, moist, mild weather. Then four
days (from January 24 to January 28, 1787) of frost and snow; after
which mild showery weather to February 16, dry cool weather to February
28, stormy and rainy weather to March 10. The next fortnight bright and
frosty; then mild rainy weather to the end of April.
November, 1787, was mild till the 23rd, the last week frosty. The
first three weeks of December still and mild, with rain, the last week
frosty. The first thirteen days of January mild and wet; then five days
of frost, followed by dry, windy weather. February frosty, but with
frequent showers. The first half of March hard frost, the rest dark
harsh weather with much rain.
The winter of 1788-89 was very severe, hard frost continuing from
November 22, 1788, to January 13, 1789. The rest of January was mild
with showers. February rainy, with snow showers and heavy gales of
wind. The first thirteen days of March hard frost, with snow, and then
till April 18, heavy rain, with frost, snow, and sleet. This winter was
very severe also on the Continent.
The winter of 1789-90 was as mild as that of 1788-89 had been severe.
The record runs thus:--'November to 17th, heavy rains with violent
gales of wind. To December 18, mild dry weather with a few showers.
To the end of the year rain and wind. To January 16, 1790, mild foggy
weather, with occasional rains. To January 21' (five days only) 'frost.
To January 28, dark, with driving rains. To February 14, mild dry
weather. To February 22' (eight days) 'hard frost.' To April 5 bright
cold weather with a few showers.
In November, 1790, mild autumnal weather prevailed till the 26th, after
which there were five days of hard frost. Thence to the end of the
year, rain and snow, with a few days of frost. The whole of January,
1791, was mild with heavy rains; February windy, with much rain and
snow. Then to the end of April dry, but 'rather cold and frosty.'
November, 1791, was very wet and stormy, December frosty. There was
some hard frost in January, 1792, but the weather mostly wet and mild.
In February also there was some hard frost and a little snow. March was
wet and cold.
The record ends with the year 1792, the last three months of which
are thus described: 'October showery and mild. November dry and fine.
December mild.'
Certainly the account of the 23 years between 1768 and 1792 does not
suggest that there is any material difference between the winter
weather now common and the average winter weather a century ago. Still
it may be necessary to show, that when men spoke of mild weather in old
times, they meant what we should understand by the same expression.
A reference to rain or showery weather shows sufficiently that a
temperature above the freezing point existed while such weather
prevailed. But it might be that what White speaks of as mild weather,
is such as we should consider severe. In order to show that this is
not the case, it will suffice to examine his statement respecting the
actual temperature in particular winters, considering them always with
due reference to what he says as to their exceptional character.
Take for instance his account of the frost in January, 1768. He says
that, for the short time it lasted, this frost 'was the most severe
that we had then known for many years, and was remarkably injurious to
evergreens.' 'The coincidents attending this short but intense frost,'
he proceeds, after describing his vegetable losses, 'were, that the
horses fell sick with an epidemic distemper, which injured the winds
of many and killed some; that colds and coughs were general among the
human species; that it froze under people's beds for several nights;
that meat was so hard frozen that it could not be spitted, and could
not be secured but in cellars, &c.' On the 3rd of January a thermometer
within doors, in a close parlour, where there was no fire, fell in the
night to 20; on the 4th to 18; and on the 7th to 17-1/2 degrees, 'a
degree of cold which the owner never since saw in the same situation.'
The evidence from the thermometer is unsatisfactory, because we do not
know how the parlour was situated. But there is reason for supposing
that in the bitterest winters known during the last thirty or forty
years, a greater degree of cold than that of January, 1768, has been
experienced in England.
The frost of January, 1776, was also regarded as remarkable, and an
account of it will therefore enable us to judge what was the ordinary
winter weather of the last century.
In the first place, White notices that 'the first week of January,
1776, was very wet, and drowned with vast rains from every quarter;
from whence may be inferred, as there is great reason to believe is
the case, that intense frosts seldom take place till the earth is
perfectly glutted and chilled with water; and hence dry autumns are
seldom followed by rigorous winters.' On the 14th, after a week of
frost, sleet, and snow, which after the 12th 'overwhelmed all the
works of men, drifting over the tops of gates, and filling the hollow
lanes,' White had occasion to be much abroad. He thought he had never
before or since encountered such rugged Siberian weather. 'Many of the
narrow roads were now filled above the tops of the hedges, through
which the snow was driven into most romantic and grotesque shapes,
so striking to the imagination as not to be seen without wonder
and pleasure. The poultry dared not to stir out of their roosting
places: for cocks and hens are so dazzled and confounded by the glare
of snow, that they would soon perish without assistance. The hares
also lay sullenly in their seats, and would not move till compelled
by hunger: being conscious, poor animals, that the drifts and heaps
treacherously betray their footsteps and prove fatal to many of them.'
From the 14th the snow continued to increase, and began to stop the
road-wagons and coaches, which could no longer keep their regular
stages; and especially on the Western roads. 'The company at Bath that
wanted to attend the Queen's birthday were strangely incommoded; many
carriages of persons who got on their way to town from Bath, as far as
Marlborough, after strange embarrassments, here met with a _ne plus
ultra_. The ladies fretted, and offered large rewards to labourers, if
they would shovel them a road to London; but the relentless heaps of
snow were too bulky to be removed; and so the 18th passed over, leaving
the company in very uncomfortable circumstances, at the Castle and
other inns.'
Yet all this time and till the 21st the cold was not so intense as it
was in December 1878. On the 21st the thermometer showed 20 degrees,
and had it not been for the deep snows, the winter would not have been
very severely felt. On the 22nd, the author had occasion to go to
London 'through a sort of Laplandian scene, very wild and grotesque
indeed.' But London exhibited an even stranger appearance than the
country. 'Being bedded deep in snow, the pavement of the streets could
not be touched by the wheels or the horses' feet, so that the carriages
ran almost without the least noise.' 'Such an exemption from din and
clatter,' says White, 'was strange but not pleasant; it seemed to
convey an uncomfortable idea of desolation:
_Ipsa silentia terrent._
'The worst had not yet, however, been reached. On the 27th much snow
fell all day, and in the evening the frost became very intense. At
South Lambeth, for the four following nights, the thermometer fell to
eleven, seven, six, six; and at Selborne to seven, six, ten; and on the
31st, just before sunrise, with rime on the trees and on the tube of
the glass, the quicksilver sank exactly to zero--_a most unusual degree
of cold this for the South of England_.' During these four nights, the
cold was so penetrating that ice formed under beds; and in the day the
wind was so keen, that persons of robust constitutions could hardly
endure to face it. 'The Thames was at once frozen over, both above and
below bridge, that crowds ran about on the ice. The streets were now
strangely encumbered with snow, which crumbled and trod dusty; and
turning gray, resembled bay salt; what had fallen on the roofs was so
perfectly dry that from first to last it lay twenty-six days on the
houses in the city; _a longer time than had been remembered by the
oldest housekeepers living_.'
According to all appearances rigorous weather might now have been
expected for weeks to come, since every night increased in severity.
'But behold,' says White, 'without any apparent cause, on February 1,
a thaw took place, and some rain followed before night, making good
the observation that frosts often go off as it were at once without
any gradual declension of cold. On February 2 the thaw persisted, and
on the 3rd swarms of little insects were frisking and sporting in a
court-yard at South Lambeth, as if they had felt no frost. Why the
juices in the small bodies and smaller limbs of such minute beings are
not frozen, is a matter of curious inquiry.'
Although it is manifest that the weather of January, 1776, was severe,
yet the remarks italicised show that such weather was regarded a
century ago as altogether exceptional. Again, the cold lasted only
about three weeks. And it may be doubted whether in actual intensity
it even equalled that which was experienced in London and the south of
England generally during the first week of 1855. Certainly the evidence
afforded by such remarks as I have italicised in the above-quoted
passage tends more to prove that winter weather in England a hundred
years hence was on the average much like winter at present, than the
unusual severity of the weather during about twenty-four days in
January, 1776, tends to suggest that a marked change has taken place.
Similar evidence is afforded by White's remarks respecting the severe
cold of December, 1784.
As in January, 1776, so in December, 1784--a week of very wet weather
heralded the approach of severe cold. 'The first week of December,'
says White, 'was very wet, with the barometer very low. On the 7th,
with the barometer at 28.5, came on a vast snow, which continued all
that day and the next, and most part of the following night: so that
by the morning of the 9th the works of men were quite overwhelmed'
(there is something quite Homeric in White's use of this favourite
expression), 'the lanes filled so as to be impassable, and the ground
covered twelve or fifteen inches without any drifting. In the evening
of the 9th the air began to be so very sharp that we thought it would
be curious to attend to the motions of a thermometer; we therefore hung
out two, one made by Martin and one by Dolland' (probably Dollond),
'which soon began to show us what we were to expect; for by ten o'clock
they fell to twenty-one, and at eleven to four, when we went to bed.
On the 10th in the morning the quicksilver of Dolland's glass was down
to half a degree below zero and that of Martin's, which was absurdly
graduated only to four degrees above zero, sunk quite into the brass
guard of the ball, so that, when the weather became most interesting,
this was useless. On the 10th, at eleven at night, though the air was
perfectly still, Dolland's glass went down to one degree below zero!
This strange severity of the weather made me very desirous to know what
degree of cold there might be in such an exalted and near situation as
Newton. We had, therefore, on the morning of the 10th, written to Mr.
----, and entreated him to hang out his thermometer, made by Adams, and
to pay some attention to it, morning and evening, expecting wonderful
phenomena in so elevated a region, at two hundred feet or more above
my house. But, behold! on the 10th, at eleven at night, it was down
only to seventeen, and the next morning at twenty-two, when mine was
at ten! We were so disturbed at this unexpected reverse of comparative
cold that we sent one of my glasses up, thinking that of Mr. ----
must somehow be wrongly constructed. But when the instruments came to
be confronted they went exactly together, so that for one night at
least the cold at Newton was eighteen degrees less than at Selborne,
and through the whole frost ten or twelve degrees; and indeed, when
we came to observe consequences, we could readily credit this, for
all my laurustines, bays, ilexes, arbutuses, cypresses, and even my
Portugal laurels--and, which occasions more regret, my fine sloping
laurel hedge--were scorched up, while at Newton the same trees have not
lost a leaf....' One circumstance noted by White, though not bearing
specially on the degree of cold which prevailed on this occasion, is
very interesting. 'I must not omit to tell you,' says White, 'that
during those two Siberian days my parlour cat was so electric that had
a person stroked her and been properly insulated, the shock might have
been given to a whole circle of people.'
White's account of this severe frost bears very significantly on the
theory that our winter weather has undergone a great change. It is
obvious, in the first place, that the situation of his thermometers
was such that they were likely to show a low temperature as compared
with the indications in other places. It is also clear that the
thermometer he used was trustworthy. If it were one of Dollond's it
would presumably be a good one, and I do not think that in White's time
the trick of marking inferior instruments with the name Dolland had
come into vogue. But in any case Adams's scientific instruments were
excellent; and, as the account shows, the thermometer used by White
indicated the same temperature as Adams's. Now, the lowest temperature
recorded was only one degree below zero; and that this was altogether
exceptional is shown not only by what White says in the passage I have
quoted, but also by his remarking a little later that this frost 'may
be allowed, from its effects, to have exceeded any since 1739-40.'
Even this is not all. It would certainly prove beyond dispute that our
winters were not milder than those of a century ago; for a greater
degree of cold than that recorded by White in December, 1784, has been
more than once experienced in the same part of England during the last
forty years. But it seems from a statement in Miller's 'Gardener's
Dictionary,' that the Portugal laurels were untouched in the great
frost of 1739-40, which would show that the frost of 1784 was more
severe and destructive than that of 1739-40. If this were really so,
the frost of 1784 was the severest (though owing to its short duration
it did not produce the most remarkable effects in the country at large)
of any during the periods noted between the years 1709 and 1788. On the
Continent, the frost of December, 1788, was more severe in some places,
though rather less severe at Paris, than that of 1709; but I do not
know of any records which would enable us to make a direct comparison
between the cold in 1709, 1784, and 1788, at any given place in Great
Britain.
It will be well now to take a wider survey and consider some of the
most severe winters experienced in Europe generally.
The winter of 1544 was remarkably severe all over Europe. In Flanders,
according to Mézerai, wine froze in casks, and was sold in blocks by
the pound weight. The winter of 1608 was also very severe. In the
winter of 1709 the thermometer at the Paris Observatory recorded a
cold of nearly ten degrees below zero.
Passing over the winter of 1776, of whose effects in England we have
learned enough to enable us to judge how severely it must have been
felt in those continental countries where the winter is always more
severe than with us, we come to the severe winter of 1788-89.
We have seen that in England hard frost began on November 22 and
continued till January 13. In France (or rather at Paris) the frost
began three days later, but the thaw began on the same day, January
13. There was no intermission except on Christmas Day, when it did not
freeze. In the great canal at Versailles the ice was two feet thick.
'The water also froze,' says Flammarion, 'in several very deep wells,
and wine became congealed in cellars. The Seine began to freeze as
early as November 26, and for several days its course was impeded, the
breaking up of the ice not taking place until January 20 (1789). The
lowest temperature observed at Paris was seven degrees below zero, on
December 31. The frost was equally severe in other parts of France
and throughout Europe. The Rhone was quite frozen over at Lyons, the
Garonne at Toulouse, and at Marseilles the sides of the docks were
covered with ice. Upon the shores of the Atlantic the sea was frozen to
a distance of several leagues. The ice upon the Rhine was so thick that
loaded wagons were able to cross it. The Elbe was covered with ice, and
also bore up heavy carts. The harbour at Ostend was frozen so hard that
people could cross it on horseback; the sea was congealed to a distance
of four leagues from the exterior fortifications, and no vessel could
approach the harbour.'
It was during the frost of 1788-89 that a fair was held on the Thames.
The river was frozen as low as Gravesend; but it was only in London
that booths were set up. The Thames fair lasted during the Christmas
holidays and the first twelve days of January.
At Strasburg, on December 31, a temperature of fifteen degrees below
zero was shown. At Berlin on the 20th, and St. Petersburg on the 12th,
temperatures of twenty and twenty-three degrees below zero respectively
were noted. But in Poland and parts of Germany an even greater degree
of cold was recorded. For instance, at Warsaw, 26-1/2 degrees below
zero; and at Bremen thirty-two degrees. At Basle, on December 18, the
thermometer indicated nearly thirty-six degrees below zero. In the
district around Toulouse bread was frozen so hard that it could not be
cut till it had been laid before the fire. Many travellers perished in
the snow. At Lemburg, in Galicia, thirty-seven persons were found dead
in three days towards the end of December. The ice froze so thick in
ponds that in most of them all the fish were killed.
The winter of 1794-95 was remarkable in this country as giving the
lowest average temperature for a month ever recorded in England. The
mean temperature for January, 1795, was only 26.5 degrees; or more
than three degrees lower than that of last January. January 25, 1795,
is commonly supposed to have been the coldest day ever known. The
thermometer in London stood at eight degrees below zero during part of
that bitter day; and in Paris, where also there were six consecutive
weeks of frost, at 10-3/7 degrees below zero. The Thames was frozen
over at Whitehall in the beginning of January. The Marne, the Scheldt,
the Rhine, and the Seine were so frozen over that army corps and heavy
carriages crossed over them. Perhaps the strangest of all the recorded
results of cold weather occurred during the same month. The French
General Pichegru, who was then operating in the North of Holland, sent
detachments of cavalry and infantry about January 20, with orders to
the former to cross the Texel and to capture the enemy's vessels, which
were 'imprisoned by the ice.' 'The French horsemen crossed the plains
of ice at full gallop,' we are told, 'approached the vessels, called on
them to surrender, captured them without a struggle, and took the crews
prisoners:' probably the only occasion in history when effective use
could have been made of a corps of horse-marines.
The winter of 1798-99 was very cold, but not so exceptionally cold
in England as on the Continent. The Seine was completely frozen over
from the 29th of December to the 19th of January, from the Pont de la
Tournelle to the Pont Royal. Farther east the cold was much greater.
The Meuse was frozen over so thickly that carriages could cross it, and
at the Hague and at Rotterdam fairs were held on the river. A regiment
of dragoons starting from Mayence, crossed the Rhine upon the ice.
The winter of 1812-13 was exceeding cold in November, December and
January. It was this unusually early and bitter winter which occasioned
the destruction of Napoleon's army in Russia, and the eventual
overthrow of his power. (For no one who considers his achievements
during the campaigns of 1813 and 1814 can doubt that, had the army
with which he invaded Russia been at his command, he would have foiled
all the efforts of combined Europe against him.) The cold became
very intense in Russia after the 7th of November. On the 17th the
thermometer fell to 15 degrees below zero, according to Larrey, who
carried a thermometer suspended from his button hole. The retreat from
Moscow began on the 18th, Napoleon leaving the still burning city on
the 19th, and the evacuation being complete on the 23rd. Everything
seemed to conspire against Napoleon and his army. During the march
to Smolensk snow fell almost incessantly. Even the only intermission
of the cold during the retreat caused additional disaster. On the
18th of November, Russian troops had crossed the frozen Dwina with
their artillery. A thaw begun on the 24th, but continued only for a
short time; 'so that from the 26th to the 29th the Beresina contained
numerous blocks of ice, but yet was not so frozen over as to afford a
passage to the French troops.' It was to this circumstance that the
terribly disastrous nature of the passage of the Beresina must mainly
be attributed.
The winter of 1813-14 was colder in England than on the Continent--I
mean, the winter here was colder for England than the winter in any
region of continental Europe was for that region. The frost lasted from
December 26 to March 21, and the mean temperature of January was only
26.8 degrees. The Thames was frozen over very thickly, and a fair was
held on the frozen river.
The winter of 1819-20 was bitter throughout Europe. Mr. Thomas Plant,
in an interesting letter to the _Times_ of February 4, says that this
winter was one long spell of intense frost from November to March,
and was almost as severe as that of 1813-14. In Paris there were
forty-seven days of frost, nineteen of which were consecutive, from
December 30, 1818, to January 17. 'In France,' says Flammarion, 'the
intensity of the cold was heralded by the passage along the coast of
the Pas de Calais of a great number of birds coming from the farthest
regions of the north by wild swans and ducks of variegated plumage.
Several travellers perished of cold; amongst others a farmer near
Arras, a gamekeeper near Nogent (Haute Marne) a man and woman in
the Côte d'Or, two travellers at Breuil, on the Meuse, a woman and
a child on the road from Etain to Verdun, six persons near Château
Salins (Meurthe), and two little Savoyards on the road from Clermont
to Chalons-sur-Saône. In the experiments made at the Metz School of
Artillery, on the 10th of January, to ascertain how iron resisted low
temperatures, several soldiers had their hands or their ears frozen.'
During this winter the Thames, the Seine, the Rhône, the Rhine, the
Danube, the Garonne, the lagoons of Venice, and the Sound, were so far
frozen that it was possible to walk across them on the ice.
The winter of 1829-30 was remarkable as the longest winter of the first
half of the present century. The cold was not exceptionally intense,
but the long continuance of bitter weather occasioned more mischief in
the long run than has attended short spells of severer cold. The river
Seine was frozen at Paris first for twenty-nine days, from December
28th to January 26th, and then for five days from February 5th to
February 10th. The river had not been so many days frost-bound in any
winter since 1763. Even at Havre the Seine was frozen over; and at
Rouen a fair was held upon the river on January 18th. On January 25,
after a thaw of six days, the ice from Corbeil and Melun blocked up the
bridge at Choisy, forming a wall 16-1/2 feet high.
The winter of 1837-38 was remarkable for the long frost of January
and February, 1838. It lasted eight weeks. Mr. Plant mentions that
'the lowest point of the thermometer during this long and severe frost
occurred on January 20, when the readings were from 5 degrees below
zero, in this district' (Moseley, near Birmingham), 'to 8 and 10
degrees below zero in more exposed aspects.' 'On the 13th of January,
the old Royal Exchange, London, was destroyed by fire; and the frost
was so great that, when the fire brigade had ceased playing on one
portion of the burning pile, the water in a short time became icicles
of such large dimensions, that the effect has been described as grand
in the extreme.'
The winter of 1837-38 is not usually included as one among the
exceptionally cold winters on the Continent, and the winter of 1840-41,
though certainly cold in the British Isles, is not included by Mr.
Plant in his list of the coldest winters since 1795. But this winter
was exceedingly cold on the Continent. At Paris there were fifty-nine
days' frost, twenty-seven of them consecutive--viz. from December 5th,
when the cold began, to January 1st. The intermission which began on
January 1, lasted only till January 3, when there was another week of
frost. There was frost again from January 30 to February 10. One of the
most remarkable stories connected with the cold of this winter is thus
told by Flammarion:--'On the 15th of December, the ashes of Napoleon,
brought back from St. Helena, entered Paris by the Arc de Triomphe.
The thermometer in places exposed to nocturnal radiation, had that day
marked 6.8 degrees above zero. An immense crowd, the National Guard of
Paris and its suburbs, and numerous regiments lined the Champs Elysées,
from the early morning until two in the afternoon. Every one suffered
severely from the cold. Soldiers and workmen, hoping to obtain warmth
by drinking brandy' (the most chilling process they could have thought
of), 'were seized by the cold, and dropped down dead of congestion.
Several persons perished, victims of their curiosity: having climbed up
into the trees to see the procession, their extremities, benumbed by
the cold, failed to support them, and they were killed by the fall.'
The winter of 1844-45 was remarkable for the long duration of cold
weather. The whole of December was very cold, January not so severe,
but still cold, February singularly cold, and the frost so severe
in March that on Good Friday (March 21st) the boats, which had been
frost-bound for weeks in the canals, were still locked tightly in ice.
Mr. Plant omits to notice in the letter above-mentioned the long
winter of 1853-54, which was indeed less severe (relatively as well as
absolutely) in England than on the Continent. Still, he is hardly right
in saying, that after 1845 there was no winter of long and intense
character until January and February 1855. On the Continent the winter
of 1853-54 was not only protracted but severe, especially towards the
end of December. Several rivers were frozen over. The cold lasted from
March till November, with scarcely any intermission.
The winter of 1854-55 was still more severe than its predecessor. The
frosts commenced in the east of France in October and lasted till the
28th of April. The mean temperatures for January and February, in
England, were 31 degrees and 29 degrees respectively. This year will
be remembered as that during which our army suffered so terribly from
cold in the Crimea. But our brave fellows would have resisted Generals
January and February (in whom the Czar Nicholas expressed such strong
reliance), as well as the Russians themselves did, or maybe a trifle
better (if we can judge from the way in which Englishmen have borne
Arctic winters), had it not been for the gross negligence of the Red
Tapists.
The winter of 1857-58 was rather severer than the average, but not
much. The Danube and Russian ports in the Black Sea were frozen over in
January, 1858.
The frost of December, 1860, and January, 1861, was remarkable. The
coldest recorded mean temperature for a month in time (not the coldest
month), was that for the thirty days ending January 16, 1861,--namely,
26 degrees. Mr. Plant remarks that 'the intense cold on Christmas-eve,
1860, finds no equal in his records, since January 20, 1838. The
thermometer registered 34 degrees of frost, and in the valley of the
Rea, five to seven degrees below zero. Strangely enough, Flammarion
makes no mention of this bitter winter in his list of exceptionally
cold winters.
The winter of 1864-65 lasted from December to the end of March, all of
which four months, Mr. Plant notes, were of the true winter type. The
Seine was frozen over at Paris, and people crossed the ice near the
Pont des Arts.
The winter of 1870-71 will always be remembered as that during
which the siege of Paris was carried on, and the last scenes of the
Franco-Prussian war took place. As Flammarion justly remarks, this
winter will be classed among severe winters, because of the extreme
cold in December and January (notwithstanding the mild weather of
February), and also because of the fatal influence which the cold
exercised upon the public health at the close of the war with Germany.
'The great equatorial current,' he proceeds (meaning, no doubt, the
winds which blow over the prolongation of the Gulf Stream), 'which
generally extends to Norway, stopped this year at Spain and Portugal,
the prevailing wind being from the north. On the 5th of December there
was a temperature of 5 degrees, and on the 8th, at Montpellier, the
thermometer stood at 17.6 degrees. A second period of cold set in on
the 22nd of December, lasting until the 5th of January. In Paris the
Seine was blocked with ice, and seemed likely to become frozen over.
On the 24th there were 21.6 degrees of frost, and at Montpellier, on
the 31st, 28.8 degrees. It is well known that many of the outposts
around Paris, and several of the wounded who had been lying for fifteen
hours upon the field, were found frozen to death. From the 9th to the
15th of January a third period of cold set in, the thermometer marking
17.6 degrees' (14.4 degrees of frost) 'at Paris, and 8.6 degrees at
Montpellier. The most curious fact was that the cold was greater
in the south than in the north of France. At Brussels the lowest
temperatures were 11.1 degree in December and 8.2 degrees in January.
There were forty days' frost at Montpellier, forty-two at Paris, and
forty-seven at Brussels during these two months. Finally, the winter
average (December, January, and February) was 35.2 degrees in Paris,
whereas the general average is 37.9 degrees.' In the north of Europe
this was also a very hard winter, though the cold set in at a different
time than that noted for France. There were forty degrees of frost at
Copenhagen on February 12--that is, the temperature was 5 degrees below
zero. By the documents which M. Renon furnished Flammarion with for
France, 'I discover,' says the latter, 'a minimum of 9.4 degrees below
zero at Périgueux, and of 13 degrees below zero at Moulins! I find by
the documents supplied me by Mr. Glaisher,' he proceeds, 'that he also
considers the winter of 1870-71 as appertaining to the class of winters
memorable for their severity.' Lastly, in the winter which as I write
(February 10, 1879) seems to be nearly over, we have had for December
a mean temperature of only 31 degrees in the midlands--the coldest
December known there, followed by a January so cold that the mean
temperature for the midlands was only 29.8 degrees. Mr. G.J. Symons,
the well-known meteorologist, says of the past winter, that January
was the coldest for at least twenty-one, and he believes for forty-one
years, following a December which was also, with one exception, the
coldest for twenty-one years.' He gives an abstract of the temperatures
(both maximum and minimum) for November, December, and January during
the last twenty-one years, from which it appears:--
1. That the average _maximum_ temperature of November was the lowest
during the period with two exceptions, that of December the lowest with
one exception, and that of January the lowest of the whole period.
2. That the average _minimum_ of November was the lowest during the
period with four exceptions, that of December the lowest with one
exception, and that of January the lowest.
3. That the mean temperature of the three months was not only five
degrees below the average, but also lower than in any previous year out
of the twenty-one.
On the whole, the winter of 1878-79 must be regarded as the coldest we
have had during at least the last score of years, and probably during
twice that time. It was not characterised by exceptionally severe short
periods of intense cold, like those which occurred during the winters
of 1854-55, 1855-56, and 1860-61; but it has been surpassed by few
winters during the last two centuries for constant low temperature and
long-continued moderate frost. During the last ninety years there have
been only four winters matching that of 1878-79 in these respects.
* * * * *
Since the preceding pages were written the weather record for February
1879 has been completed. Like the three preceding months, February
showed a mean temperature below the average, though the deficit was not
quite so great as in those months. The following table, drawn out by
Mr. Plant, shows the mean temperature at Moseley for four winter months
of 1878-79, and the average temperature for those months at Moseley
during the last twenty years:--
1878-79
Deg.
November 37.0
December 31.0
January 29.8
February 35.8
----
Mean of the four months in 33.4
Average of 20 years
Deg.
November 41.5
December 39.0
January 35.5
February 39.0
----
Average of four months in 20
years observations 38.8
_OXFORD AND CAMBRIDGE ROWING._
The records of the last eighteen boat-races between Cambridge and
Oxford indicate clearly enough the existence of a difference of style
in the rowing of the two universities, a circumstance quite as plainly
suggested by the five successive victories of Cambridge in the years
1870-74, as by the nine successive victories of Oxford which preceded
them. For it is, or should be, known that the victories of Cambridge
only began when Morrison, one of the finest Oxford oarsmen, had taught
the Cambridge men the Oxford style, so far as it could be imparted to
rowers accustomed, for the most part, in intercollegiate struggles,
to a different system. With regard to the long succession of Oxford
victories which began in 1861, and which, be it noticed, followed on
Cambridge successes obtained when the light-blue stroke rowed in the
Oxford style, I may remark that, viewing the matter as a question of
probabilities, it may safely be said that the nine successive victories
of Oxford could not reasonably be regarded as accidental. The loss of
three or four successive races would not have sufficed to show that
there was any assignable difference in the conditions under which the
rival universities encountered each other on the Thames. In cases
where the chance of one or other of two events happening is exactly
equal, there will repeatedly be observed recurrences of this sort.
But when the same event recurs so often as nine successive times,
it is justifiable to infer that the chances are _not_ precisely--or
perhaps even nearly--equal. I believe I shall be able to indicate the
existence of a cause quite sufficient to account for the series of
defeats sustained in the years 1861-69 by Cambridge, and for the change
of fortune experienced when for a while the Cambridge oarsmen adopted
the style of rowing which has prevailed for many years at the sister
university.
I may premise that Cambridge has an important advantage over Oxford
in the fact that she has a far larger number of men to choose from
in selecting a university crew. It may seem to many, at first sight,
that as good a crew might well be selected from three hundred as from
five hundred boating-men; because it is not to be supposed that either
number would supply many more than eight first-rate oarsmen. But it
must be remembered that there are first-rate oarsmen _and_ first-rate
oarsmen. The unpractised eye may detect very little difference
between the best and the worst oarsmen in such crews as Oxford and
Cambridge yearly send to contend for the blue-riband of the river.
But differences exist; and if the best man of the crew were replaced
by one equal in rowing ability to the worst, or _vice versâ_, an
important difference would be observed in the time of rowing over the
racing course, under similar conditions of wind, tide, and so forth.
Accordingly, a large field for the selection of the men is a most
important advantage. Taking, for instance, the five hundred rowing men
of Cambridge and dividing them into two sets--one of three hundred men,
corresponding to the three hundred rowing men of Oxford, and the other
of two hundred men--we see that the first set ought to supply a crew
strong enough to meet Oxford, and the second a crew nearly as strong.
Now, if the best men of the two Cambridge crews thus supposed to be
formed are combined--say five taken from the first and three from the
second, all the inferior men being struck out--a far stronger crew than
either of the others would undoubtedly be formed.
So that if Cambridge were generally the winner in these contests, the
Oxonians would be able to account for their want of success in a
sufficiently satisfactory manner. The successive defeats sustained by
the Cambridge crews in 1861-69 are therefore so much the less readily
explained as due to mere accident, by which of course I mean simply
such an accidental circumstance as that better oarsmen chanced to be at
Oxford than at Cambridge in these years, not to accident occurring in
the race itself.
Several reasons were assigned from time to time for the repeated
victories of Oxford. Some of these may conveniently be examined here,
before discussing what I take to be the true explanation.
Some writers in the papers advanced the general proposition that Oxford
men are as a rule stronger and more enduring than Cambridge men.
They did not tell us why this should be the case--to what peculiar
influences it was due that the more powerful and energetic of our
English youth should go to one university rather than the other. No
evidence of this peculiarity could be found in the university athletic
sports, in which success was, as it has since been, very equally
divided. And what made the theory the less satisfactory was the
circumstance that it afforded no explanation of the early triumphs of
the Cantabs, who won seven of the nine races they rowed against Oxford.
Of these races five were rowed from Westminster to Putney, a course
two miles longer than the present course from Putney to Mortlake. A
race over such a course and in the heavier old-fashioned racing-boats
was a sufficient test of strength and endurance; yet the Cambridge
men managed to win four out of these five events, and that not by a
few seconds, but in three instances by upwards of a minute. If there
were any reason for conceiving that Oxonians were as a rule stronger
than Cantabs in the years 1861-69, there is at least no reason for
conceiving that any change can have taken place in the time between the
earlier races and that during which Oxford won so persistently. And as
the earlier races show no traces of any difference such as was insisted
upon by many journalists in the latter part of the period of the
Oxford successes, we may reasonably conclude that the difference had no
real existence.
Another theory resembling the preceding was also often urged. It was
said repeatedly in the papers that Cambridge traditions encouraged
a light flashy stroke, pretty to look at but not effective; that
again, Cambridge rowed the first part of the course well but
exhausted themselves before the conclusion of the race, through their
over-anxiety to get the advantage of their opponents in the beginning
of the contest. Critics undertook to say that the Oxford men 'rowed
within themselves' at first, reserving their strength for the last
mile or two of the course. Now, it will presently appear that there
does exist in a certain peculiarity of what may justly be called the
Cambridge style, a true cause for want of success, and even for such a
repeated series of defeats as the light-blue flag sustained in 1868-69.
But the Cambridge style rowed during these years was very far from
being a flashy style. On the contrary, the old Cambridge style, which
is still too often seen in College contests, and has within the last
four years been seen on the Thames, involves the rowing of a longer
stroke than _seems_ to be rowed in the true Oxford style. Oxford
rowing is pre-eminently lively. Anyone who had been at the pains to
time the strokes of the Oxford and Cambridge crews during the years
1861-69, would have been able at once to dispose of the notion that
Cambridge men row the more rapid stroke. In these nine races, as in
the practice preceding them, the Oxford crew often took forty-four
strokes per minute. Especially did they rise to this swift stroke in
some of those grand spurts which so often carried the dark-blue flag
in front. I do not remember that the Cambridge crews ever went beyond
forty-two strokes per minute. Then again as to starting early and
being quickly spent, a good deal of nonsense was written. In some of
the later contests of the series 1861-69, indeed, the Cambridge crews,
urged by the thought of numerous past defeats, made unduly exhausting
efforts in the earlier part of the race. But nothing was done in this
way which would have caused the loss of the race if the Cambridge crew
had really had it in them to win. If the better of two crews puts on
rather too much steam at first, they draw so quickly ahead that they
soon begin to feel that they have the race in hand, and so proceed to
take matters more steadily. In such powerful and well-trained crews
as both universities usually send to the contest, very little harm is
done by varying the order of the work a little--rowing hard at first
and steadily afterwards, or _vice versâ_. It is easy for lookers-on,
most of whom have never taken part in a boat-race, to theorise on these
matters. But those who know what boat racing is (as distinguished, be
it noticed, from most contests of speed) know that the better boat is
almost sure to win in whatever way the stroke may set them their work.
A good crew, unlike a good horse, requires no jockeying.
The difference of the rivers Cam and Isis has been urged as a
sufficient reason for inferiority on the part of the Cambridge crews.
That the difference used to tell unfavourably upon the chances of the
light blue flag before the river had been widened and the railway
bridge modified, and that even now the Cambridge crews would not be all
the better for a better river to practice on, cannot be denied. But I
question whether even before the widening of the river, this particular
cause sufficed to counterbalance the advantage of the Cantabs in point
of numbers. Nor do I think that those who urged the inferiority of the
Cambridge river have recognised the principal disadvantage which it
entailed upon the light-blue oarsmen.
The first circumstance to be noticed, in this connection, is the
difference in the conditions under which racing-boats were and are
steered along the two rivers. A Cambridge coxswain has in some respects
an easier, in others a more difficult task than the Oxonian. In the
first place, he has very little choice as to the course along which
he shall take his boat. All he has to do is to steer as closely round
each corner as possible; and the narrowness of the river renders
it difficult for him to fall into any error in running a straight
line from corner to corner. The Oxonian coxswain, on the other hand,
requires to be more carefully on the watch lest he should suffer his
boat to diverge from the just course, which is far less obvious on
the wider Isis than on the Cam. But although the Cambridge coxswain
has the shores of the river close to him on either hand, and can thus
never be at a loss as to his just course, yet to maintain this obvious
course he has to be continually moving the rudder-lines. In fact,
there are some 'eights' which steer so ill that it is no easy matter
to keep them from the shores when the crew are sending them along at
racing speed. In rounding the three great corners which have to be
passed in the ordinary racing-course at Cambridge--viz., First Post
Corner, Grassy Corner, and Ditton Corner--the rudder has to be made
use of in a much more decided manner than in the straighter course
along which the Oxford racing eights have to travel. I have seen the
water bubbling over the rudder of a racing eight, as she rounded Grassy
Corner, in a manner which showed clearly enough how her 'way' must have
been checked; yet, probably, if the rudder-lines had been relaxed for
a moment, the ill-steering craft would have gone irretrievably out of
her course, and been presently stranded on the farther bank. And even
eights which steer well had to be very carefully handled along the
narrow and winding ditch which we Cantabs used to call 'the river.'
A more serious disadvantage, so far as the prospects of University
Boats were concerned, lay in the circumstance that there was no part
of the Cam (within easy reach, at least, of Cambridge) along which the
crew could row without a break, for four or five miles, as they had to
do in the actual encounter with the Oxford boat. The whole range of the
river between the locks next below Cambridge and Bait's Bite Locks, is
somewhat under four miles and a half. But about a mile and a quarter
from Bait's Bite sluice, the railway-bridge crosses the river, and
until a few years ago, the supports of this bridge divided the river
into three parts. There was in my time a vague tradition that the
University Eight had once or twice been steered through the widest of
these passages without stopping; but I doubt much whether there could
have been any truth in the story. Certainly no coxswain in my time at
Cambridge ever achieved the feat, nor could it be safely attempted even
by the most skilful steersman. The consequence was that there was a
break in the long course which took away all its value as a preparation
for the actual race. It may seem to the uninitiated a trifling matter
that a crew should get a few seconds of rest in so long a pull. But
those who know what racing is, are aware that the slightest break--one
stroke even, shirked--is an immense relief to the tugging oarsman.
Beyond Bait's Bite Locks there is a three-and-a-half-miles course,
liable to be broken by the manoeuvres of a floating bridge or
ferry boat opposite Clayhithe. Next comes another short course
extending to Upware. And lastly from Upware to Ely there is a fine
five-and-a-half-miles course, considerably wider than the Cam, and
presenting several splendid reaches. To this course the Cambridge men
used to betake themselves four or five times in the course of their
preparation for the great race. But a course so far removed from the
university itself was clearly far less advantageous than the convenient
Oxford long course, extending from the ferry at Christ Church meadows
to Newnham. Still, annoying as the want of a convenient long-course
must be considered, I cannot attribute the long succession of Cambridge
defeats in 1861-69 to such a cause as this. It is true that before the
railway-bridge was built, the Cambridge crew used generally to win, and
that since it has been so far modified as not to interfere with the
passage of a racing eight, they have again been successful, whereas,
while the supports of the bridge checked them midway on their course,
they were less fortunate. But to connect these circumstances as cause
and effect, would be as unsafe as the theory of the Margate fishermen
who ascribed the Goodwin Sands to the building of the Reculvers.
It has been said that the shallowness of the Cam affects the style of
Cambridge oarsmen. This seems to me a fanciful theory. Occasionally in
the course of a race close steering round one or other of the sharper
corners might permit the oarsmen to 'feel the bottom,' for two or
three strokes; but during all the rest of the course the oars find
plenty of water to take good hold of. The Cam was undoubtedly growing
shallower for some time after 1860; and the change gave some degree of
support to the theory that the peculiarities of the Cambridge style
were due to the peculiarities of the Cambridge river. But I believe
the notion was a wholly mistaken one; and I am confirmed in this
belief by noticing that the Cambridge style from 1860 to 1869 was in
all essential respects, and especially in that feature which I shall
presently describe as its radical and fatal defect, the same precisely
as it had been in earlier times when Cambridge was oftener successful
than defeated.
I have heard Cambridge men say, indeed, that after rowing on the Cam
they feel quite strange on Thames water. They feel, they say, as if
the boat were running away with them. I have experienced the feeling
myself, when rowing on the Thames anywhere below Teddington; but most
markedly below Kew. It is not due, however, to the mere difference
in the depth of the two streams, but mainly, if not wholly, to the
circumstance that the lower part of the Thames is a tidal river. It is
not noticeable above Teddington, save (in a somewhat modified form) in
those portions of the river called 'races,' where the stream runs with
unusual rapidity. I should suppose that Oxonians felt the influence of
this peculiarity fully as much as Cambridge oarsmen do; in fact, I know
that this is the experience of some Oxonians, for they have told me as
much.
I believe that the principal disadvantage which the narrowness of the
Cam entailed upon boating-men at Cambridge, lay in the circumstance
that Cambridge men never had an opportunity of rowing a level race.
They had 'bumping races' for the college eights--as the Oxonians
had--and time-races to decide between the merits of two or three boats,
whereas at Oxford two boats could contend side by side. Thus it was
to many Cambridge men a novel and somewhat disturbing experience to
find themselves rowing close alongside of their opponents. It may seem
fanciful to notice any disadvantage in such a matter as this; yet I
believe that the matter was not a trifle. The excitement which men
feel just before a race begins, and during the first half-mile or so
of its progress, is so intense that a small difference of this sort is
apt to produce much more effect than might be expected. I think the
somewhat flurried style in which the Cantabs were often observed to row
the first half-mile of the great race might be partly ascribed to this
cause. Of course, I am far from saying that if a Cambridge crew had
been decidedly better than their opponents, the race could have been
lost or even endangered from such a cause as this.
And now it remains that I should point out that peculiarity in what
may be called the Cambridge style of rowing--though it is not now
systematically adopted by Cambridge crews--to which the defeats of
the light-blue flag in the years 1861-69 were I believe to be chiefly
attributed.
It should be remembered that before we can recognise a peculiarity
of style as the cause of a long series of defeats, it must be shown
that the peculiarity is neither trifling nor accidental. There are
peculiarities in rowing which have a very slight effect upon the speed
with which the boat is propelled by the crew. Amongst these may be
fairly included such points as the following:--the habit of throwing
out the elbows just before feathering, feathering high or low, rowing
short or long (a technical expression now commonly, though incorrectly,
applied to the length of the stroke, but properly relating to the
distance at which the stretcher or foot-board is placed from the seat),
sitting high or low, and so on. All these peculiarities--of course
within reasonable limits--are unimportant, save in so far as they
indicate that the style of the stroke itself is faulty. Then again
there are accidental peculiarities, which may be exceedingly important
in themselves, but which yet produce only a transient influence,
because they are personal peculiarities of such and such a stroke, and
when he has left his university they remain no longer in vogue. As an
illustration of this sort of peculiarity, I may notice the remarkably
effective stroke rowed by Hall of Magdalen in the year 1858-60. There
the radical defect of the Cambridge style was almost obliterated, and
all the good points of that style were fully brought out. The result
was that, out of three races rowed with Oxford, Cambridge won two, and
though they lost the third, yet they lost it in such a manner as to
obtain more credit than any winning race could have brought them. I
refer to the memorable race of 1859, in which the Cambridge boat was,
at starting, half full of water, and gradually filling as the race
proceeded, sank about half-a-mile from the winning-post, being at the
moment of sinking only four lengths behind Oxford, notwithstanding
the tremendous difficulties under which the crew had all along been
rowing.[13] Mr. Hall also rowed stroke in the great race with the
famous London crew--Casamajor, Playford, the two Paynes, &c.--when
Cambridge won by half a boat's length. We have, however, to inquire
whether there is any point held to be essential by Cambridge oarsmen,
which is sufficiently important and sufficiently faulty to account for
the marked want of success which attended the light-blue flag in the
years 1861-69. The following peculiarity appears to me to be precisely
of such a character.
It was formerly held by nearly all the Cambridge oarsmen that 'the
instant the oar touches the water' (I am quoting from a pamphlet called
'Principles of Rowing,' much read by rowing-men at Cambridge) 'the arms
and body should begin to fall backwards, the former continuing at their
full stretch till the back is perpendicular; they are then bent, the
elbows being brought close past the sides,' etc. If a Cambridge oarsman
broke this rule, so that his arms began to bend before his back was
upright, he would be told that he was jerking. 'This is caused,' says
our authority, 'by pulling the first part of the stroke with violence
and not falling gradually backwards to finish it. The most muscular men
are more than others guilty of it, because they trust too much to their
arms, instead of making each part of the body do its proportionate
quantity of work. It is most annoying to the rest of the crew, injures
the uniform swing throughout the boat, and soon tires out the man
himself, however strong he may be, because he is virtually rowing
unsupported, and he has nearly the whole weight of the boat on his arms
alone.'
I was myself trained to row the Cambridge style, and when I became
captain of a boat-club, I was careful to inculcate this style
on my crew, and on other crews which came more or less directly
under my supervision. But I am convinced that the peculiarity so
carefully enjoined in past time by the Cambridge club-captains, and
still retained, is altogether erroneous for boats of the modern
build. I first became aware that the Cambridge style is not the
water-man's--and, therefore, presumably not the most effective--through
practising in a racing-four with three of our most noted Thames
watermen--the two Mackinnys, and Chitty of Richmond. They were then
preparing for the Thames National Regatta, though not as a set crew.
Accordingly the coxswain would frequently call upon us for a good
lifting spurt of a quarter of a mile or so. During these spurts the
coxswain was continually telling me that I was not keeping stroke,
and I was sensible myself that something was going wrong. One who
has taken part in boat-races very soon detects any irregularity in
the rowing--by which I do not of course refer to so gross a defect as
not keeping time. All the men of a crew may be keeping most perfect
time, and may even present the appearance of keeping stroke together,
and yet may not be feeling their work simultaneously. I was aware
that something was going wrong, but I found it impossible, without
abandoning the style of rowing in which I had been so carefully
trained, to keep stroke with the rest of the crew. It seemed to me that
they were doubling over their work, because while I was still swaying
backwards they had reached the limit of their swing. Then they did not
seem to me to feather with that lightning flash which the Cambridge
style enjoins. Altogether, I left them after three or four long pulls
with the impression that, though they might be very effective watermen,
they had but a poor style.
Soon after, however, I had occasion to watch Oxford oarsmen at their
work, and I found that they row in a style which, without being
actually identical with that of the London waterman, resembles it in
all essential respects. The moment the oar catches the water, the body
is thrown back as in the Cambridge style, but the arms, instead of
being kept straight, immediately begin to do their share of the work.
The result is that when the body is upright the arms are already bent,
and the stroke is finished when the body is very little beyond the
perpendicular position.
Now let us compare the two strokes theoretically. In each stroke the
body does a share of the work, and in the Cambridge stroke the body
even seems to do more work than in the Oxford stroke, since it is
swayed farther back. In each stroke, again, the arms do a share of the
work, but in the Oxford stroke the work of the arms is distributed
equally as a help to that of the body, whereas in the Cambridge stroke
the work of the arms is all thrown upon the finish of the stroke. At
first sight it seems to matter very little in what order the work is
done, so long as the same amount of work is done in the same space of
time. But here an important consideration has to be attended to.
There are two things which the oarsman does in whatever style he rows.
He propels the boat along, by pressing the blade of his oar against the
water as a fulcrum; but he also propels his oar more or less through
the water. If instead of the actual state of things, the boat were to
slide along an oiled groove in some solid substance, whose surface was
so ridged that the oar could bear upon the ridges without any flexure,
then indeed it would matter very little in what way the oar was pulled,
so long as it was pulled through a good range in a short space of time.
But the actual state of things being different, we have to inquire
whether it is not possible that one style of rowing may serve more than
another to make the slip of the oar through the water (a dead loss, be
it remarked, so far as the propulsion of the boat is concerned) bear
too large a proportion to the actual work done by the rower.
Let us make a simple illustration. Suppose a person standing on the
edge of a sheet of water seeks to propel across the sheet a heavy
log lying near the bank. If he gives the log a violent kick, it will
scarcely move at all through the water, but after a few vibrations
will be seen to lie a few inches from its former position. The force
expended has not been thrown away, however, but has resulted in a
violent shock to the kicker. But if instead of kicking the log the
person apply the same amount of force gently at first and then with
gradually increasing intensity, the log will receive a much more
effective impetus, and its motion will continue long after the force
has ceased to be exerted. The same amount of force which before
produced a motion of a few inches will now project the log several
yards.
And now to apply this illustration. If the object of the rower were to
move his oar through the water--the boat being supposed for the moment
to be a fixture--he could not do better than to adopt the Cambridge
style of pulling. For this style gives a steady pressure on the oar
at the beginning of the stroke, followed by a gradual increase, and
ending by a sharp lift through the water. On the contrary, the Oxford
style, in which arms and body apply all their strength at once to the
oar, would probably, as in the case of our imaginary _fixed boats_,
result in the fracture of the oar. If the boat were not fixed, but very
heavy and clumsy, conclusions very different from the above would be
arrived at. The Oxford style would be unsuitable to the propulsion of
a heavy boat, because, although the oar would have very little slip
through the water, yet the boat itself could not be moved in so sudden
a manner as to make the applied force available. On the other hand,
the Cambridge style would be very suitable; because, although there
would be considerable 'slip' this would in any case be inevitable, and
the force would be applied to the boat (as well as to the oar) in the
gradual increasing manner best suited to produce motion through the
water. Hence we can understand the long series of victories gained by
the light-blue oarsmen in the 'old fashioned racing eights'. But when
we come to consider the case of a boat like the present wager-boat--a
boat which answers immediately to the slightest propelling force--we
see that that mode of rowing must be the most effective which permits
the oar to have the least possible motion _through_ the water, which
lifts the boat along from the water _as from an almost stable fulcrum_.
Hence it is that that sharp grip of the water which is taken by London
watermen, and by rowers at Oxford, Eton, Radley, and Westminster, is so
much more effective than the heavy drag followed by a rapid and almost
jerking finish which marks the Cambridge style.
The mention of public-school rowing leads me to urge another
consideration. There are public-school oarsmen at Cambridge, and
they hold, as might be supposed, a high position amongst university
rowing-men. In general they form so small a minority of college
racing-men, that they have to give up their own workmanlike style, and
adopt the style of those they row with. But there is one club--the
Third Trinity Club--which consists exclusively of Eton and Westminster
men, and although it is a small club, it has been repeatedly at the
head of the river, holding its own successfully against clubs which
have sent in far heavier and better-trained crews. But even more
remarkable is the fact that powerful college crews were sent from
Cambridge to Henley between the years _1860-69 which have actually
been unable to maintain their own against Eton lads_! This of itself
suffices to show that there was something radically wrong in the style
then prevalent at Cambridge; for in such races age, weight, strength,
and length of practice were all in favour of the Cambridge crews.
When I first expressed these views about the Oxford and Cambridge
style in the 'Daily News' in April 1869, several Oxford and Cambridge
men denied that the difference between the two styles was that which
I have indicated, asserting that neither Oxford nor Cambridge oarsmen
advocated working with the arms in the beginning of the stroke. It was
so great a novelty to myself to learn, in 1858, that London watermen
row in the manner I have described, and I found the very watermen who
rowed in that way so confidently denying that they did so, that I was
not greatly surprised to find many University men, and not a few of
the first University oarsmen, persisting that the rules laid down in
'Principles of Rowing' before the modern racing-boats were used are
still valid and are still followed at Oxford as well as Cambridge. It
was denounced as a special heresy to teach that work should be done by
the arms at the beginning of the stroke, instead of the old rule being
followed according to which the arms were to remain straight till the
body was upright in the backward swing, the work being done entirely
by the body and legs up to that moment, and then finished by the arms.
But before I ventured to enunciate a theory on the subject I had been
careful to apply a number of tests not only while watching Oxford and
Cambridge eights, but in actual practice. I had inquired diligently
also of those who are not merely able to adopt a good rowing style but
to analyse it, so as to learn precisely where and how they do their
work. In some cases, I found first-rate oarsmen had given very little
thought to the matter; but on the question being put to them, they
quickly recognised the essential principles on which the most effective
and the least tiring style for the modern racing-boat depends. One
such oarsman said to me, after giving a few days' trial as well as
thought to the matter--'You are quite right; arms, legs, and body must
work together from the very beginning'; the work is done when the body
comes upright; and not only must this be so for the work to be done in
the most effective way, but it is essential also if the hands are to
be quickly disengaged, the recovery quick, and a good reach forward
obtained.
I found, however, that the essential distinction between a good style
in the modern racing eight, and a good style in the old-fashioned
boats, had been recognised (at least, so far as the modern boats are
concerned) a year before my article in the 'Daily News' appeared. In an
article on 'Water Derbies,' 'Wat Bradwood,' describing the University
race of 1868, draws the following distinctions between the two crews,
which precisely accord with my own observations on that occasion; only
it is to be noticed that, whereas he is describing the beginning of
the race, the whole of which he witnessed from the Umpire's boat, my
observations were made from the shore not far from the finish, when
Oxford was so far ahead that there was ample time to note separately
and closely the style of each boat:--'The styles of progress of the
two boats themselves are palpably distinct,' he says; 'Cambridge
take a shorter time to come through the air than to row through the
water; they go much farther backward than Oxford, and are very slow
in getting the hands off the chest; their boat is drawn through the
water at each stroke, but has hardly any perceptible "lift." Oxford,
on the other hand, swing just the reverse of Cambridge, a long time in
getting forward' (he means of course, a _relatively longer_ time, for
no good oarsman would ever take a long time in getting forward), 'and
very fast through the water, driving the oars through with a hit like
sledgehammers, while the boat jumps out of the water several inches
at each stroke.' These last words again relate rather to contrast
between the boats than to the actual lift. The 'drag at the end' in
the Cambridge style used always to dip the nose of the eight, whereas
the quick disengagement of the hands in the Oxford style prevents any
dipping, so that by contrast the Oxford boat seen beside the Cambridge
seemed lifted at the end of each stroke. In reality there was very
little if any lifting, though the sharp grip of the water at the
beginning of the stroke caused the boat to dip a little as compared
with her position at the end. Theoretically, the less change of level
throughout the stroke (from feather to finish) the better; but if there
is any such change, it is far better it should be of the nature of a
lift above the flotation-level than of the nature of a dip below that
level.
Again, towards the close of the same article 'Wat Bradwood' made the
following pertinent remarks respecting the Oxford style in 1868 and
generally: 'The general style of Oxford has not deteriorated; though
many outsiders fancied that Oxford rowed a short stroke, it was more
that the time occupied by them in slashing the oar through the water
was short than the reach itself; this deceived inexperienced eyes,
especially when compared to the slow 'draw through' (query 'drag') of
Cambridge, which often appeared for similar reasons a longer stroke
than it really was.[14] He attributed the defeat of the Cantabs, who
were a stronger set of men than the Oxonians, to the teaching of their
'coach,' who had been (though this he does not mention) as good a
'coach' as ever existed for rowing in the old fashioned style of boats,
but whose 'experience availed nothing to teach the modern style of
light-boat rowing.'
In another article by the same writer, in the 'Pall Mall Gazette,'
(1868), a noteworthy illustration is given of the value of a good
style. 'Among the college boats in the first division at Cambridge this
year, the strongest were perhaps First Trinity, Trinity Flail, and
notably Emmanuel; the weakest in the division was the Lady Margaret
crew,'--the crew representing St. John's College. 'But notwithstanding
this, Lady Margaret went up one place, and pressed Trinity very hotly.
There must, of course, be some special reason to account for eight
weak men proving superior to eight strong ones.' There is a little
(unintentional) exaggeration here; the stroke of the Lady Margaret
crew was a strong as well as an elegant oarsman, and two others of the
crew could certainly not be called weak; nevertheless the crew as a
whole was undoubtedly weak compared with most of the other crews of the
first division, 'That reason,' proceeds our author, 'is to be found
in _style_. Every day of practice on the Cam you hear the "coaches"
of the different racing-boats giving their crews certain directions,
some absurd, and nearly all, from some accidental reason, useless. The
chief of these is to "keep it long," and if you object to the results
of this teaching, you are told that "length" is the great requisite of
good rowing, and that "Oxford, sir, always beat us, because they are
longer than we are." Now, this is true and yet untrue. At Cambridge
"length" is acquired by making the men "finish the stroke," that is, by
making them "swing well back" beyond the perpendicular. Of course the
oar remains longer in the water, but we maintain that the extra time
it is kept there by the backward motion of the body is time lost. The
"swinging back" throws a tremendous strain on the abdominal muscles,
the weakest rowing muscles in the body; very soon the men feel this
strain, become exhausted, and unable to "get forward," and finally
lose time and swing and "go all to pieces." Length obtained by going
backwards is of no possible use. A crew ought to be "coached" to get
as far _forward_ as they can, to finish the stroke by bringing their
elbows past their sides, and their hands well into their bodies,
and then complaints about "wind" and "last" will be fewer. This was
abundantly proved in the late May races. First Trinity, it is true,
kept "head," but only because of their great strength, and because they
had a stroke who understood the duties of his position. Before, the
races every sporting newspaper, every supposed judge of rowing in the
University, was certain about only one thing, and that was that Lady
Margaret must go down; the only question was where they would stop.
They, however, not only kept away from Trinity Hall, but finished above
Emmanuel and Third Trinity, infinitely stronger' (which no doubt must
be understood as meaning 'far stronger') 'boats. The reason was that
they were the only boat on the river which rowed in anything like a
good style. They had the reach forward, the quick recovery, and the
equally quick disengagement of the hands, which marked the Oxford crew
of 1868. Consequently although a very weak lot of men, they were able
to vindicate style against strength. We hope' (added Wat Bradwood)
'that Cambridge generally will appreciate the lesson; it is one that
has not been taught them for years, and results on their own river
ought to show its value.' Less than a year after this was written,
the Cambridge boat, with Goldie, the Lady Margaret stroke, at the
aft thwart, were just beaten by Oxford in one of the best races ever
rowed, and the year after, with the same stroke, they won for the first
time in ten years. The subsequent successes of the Jesus boat on the
Cam afforded further illustrations of the superiority of style over
strength. For the Jesus boat has remained for years at the head of
the river, though the crew as a whole has often been far surpassed in
strength by the crews of Trinity, John's, and other colleges.
There is, as the writer from whom I have quoted above correctly says,
'no opposition between theory and practice in this matter, any more
than there is in metaphysics or moral philosophy.' The ill-success of
Cambridge in past years was in the main due to a want of appreciation
of theory, and the absence of due recognition of the entire change
which the introduction of the light outrigged racing-boat had produced
in the art of effective rowing. The Cambridge 'finish to the stroke,'
the 'lug at the end,' as sailors call it, was excellent with the old
fashioned boats. It was indeed essential to success in a race, as was
the lightning feather. But now the essential conditions are a sharp
grasp of the water at the beginning of the stroke, the intensest
possible action then and throughout the time the oar is in the water,
so that the oar may be as short a time as possible in the water, but
_in the time_ may have the largest possible range. This result must
not merely be obtained from each individual member of the crew, but
from all together in precisely the same time. It is necessary that
the stroke should mark the time in the most distinct and emphatic
manner. In the Cambridge style, or what at least used so to be called,
perfect time, though of course always desirable, was not so absolutely
essential as in the Oxford style. The oars being a long time in the
water, it mattered less if any oarsman was for a small fraction of a
second behind or in advance of his fellows. But with the sharp dash
upon the water and the quick tear through the water of the better
style, perfect simultaneity is all-important. The stroke must not only
have first a good style himself, and secondly a keen sense of time, but
he must have that power of making his crew know and feel what he is
doing, and what he wants them to do, which constitutes the essential
distinction between the merely steady stroke and such a stroke as every
man of the crew feels to be made for the place. When one of these 'born
strokes' occupies the aft thwart, there is no occasion for the coxswain
to tell the crew when to quicken or when to row steadily at their
hardest; for the whole crew knows and feels the purpose of the stroke
as distinctly as he knows and feels it himself.
_The following paragraph, written a few days before the race (1879) is
left unaltered. I may note that Marriott, the successful Oxford stroke
of 1878, so far succeeded in improving the style of the Oxford boat
when he took the aft thwart in '79 (far too late by the way), that
Cambridge did not win by anything like the expected distance._
[Since the above was written I have seen both the crews for the present
year's race at work. It is too early to venture a prediction as to the
result of the race, though the odds offered on Cambridge would seem to
imply that nothing short of an accident can save Oxford from a crushing
defeat. It is manifest that Cambridge has the stronger crew, and the
style of the Oxford crew at present is not such as to indicate that
this year the Oxford style will defeat superior strength. In fact, at
present, Oxford shows defects which have been wont to characterise
Cambridge crews, and which unmistakably do characterise the present
Cambridge crew, fine though it undoubtedly is. But if, as has before
now happened, the Oxford crew fall into the true Oxford style during
the fortnight before the race, the odds will not be 2 to 1 as at
present, nor even 3 to 2, on Cambridge.]
FOOTNOTES:
[Footnote 13: 'Wat Bradwood,' in an article on 'Water Derbies,'
afterwards referred to, says that Cambridge was fairly beaten when the
boat sank. He might with equal justice have said that they were fairly
beaten when they started. They never had a chance of winning from the
start, having then half a boat-full, and for some time before they sank
a whole boat-full, of water to take along with them.]
[Footnote 14: This agrees closely with my own description written
later, but independently, and flatly contradicted by more than one
Oxford oarsman at the time: 'In the case of Oxford,' I said, after
describing the lightning feather following the long sweeping stroke
of Cambridge, 'we observe a style which at first sight seems less
excellent. As soon as the oars are dashed down and catch their first
hold of the water, the arms as well as the shoulders of each oarsman
are at work. The result is that when the back has reached an upright
position the hands have already reached the chest, and the stroke is
finished. Thus the Oxford stroke takes a perceptibly shorter time than
the Cambridge stroke; it is also necessarily somewhat shorter in the
water. One would therefore say it must be less effective. Especially
would an unpractised observer form this opinion, because the Oxford
stroke seems to be much shorter in range than it is in reality. There
we have the secret of its efficiency. It is actually as long as the
Cambridge stroke, but is taken in a perceptibly shorter time. What
does this mean but that the oar is taken more sharply, and therefore
much more effectively, through the water? Much more effectively,
I proceeded, 'so far as the actual conditions of the contest are
concerned,' going on to consider the difference between the modern and
the old fashioned racing boats.--_Light Science for Leisure Hours_:
Essay on Oxford and Cambridge Rowing Styles.]
_ROWING STYLES._
Professor Marcy has recently discussed, in a lecture on Living
Locomotors (_Moteurs Animés_), the principles of propulsion. Had he
been an Englishman he would probably have found some of his most
striking illustrations among different cases of propulsion through
water. But, although he limited his discussion of animated motors to
those which work on land, he yet laid down the fundamental principle
of all propulsion, which is that as little as possible--and therefore,
if possible, none at all--of the energy employed to produce propulsion
should be expended in injurious work. Even with the best carriages, he
pointed out, there remain vibrations and shocks which must be attacked
and destroyed to render the conditions of traction more perfect; they
are veritable shocks, which use up part of the work of the horse in
giving only hurtful effects, bruising the animal's breast, injuring
his muscles, and, in spite of the padding of the collar, sometimes
wounding him. Then he showed a simple experiment suggested by the able
dynamician, Poncelet. To a weight of five kilos, (about 11lb.) a string
is attached by which the weight can be lifted, but not much more. Then
the experimenter tries to lift the weight rapidly with the string,
which breaks without moving the weight, while the fingers are more or
less hurt by the sudden shock. If now, a cord of equal strength, but
slightly elastic, is substituted, the experiment ends differently. The
sudden effort of elevation is transformed into a more prolonged action,
and the weight is raised without bruising the fingers or breaking the
cord. Yet a still more sudden movement would break the cord in this
case, though a yet more extensible cord would resist even a yet more
sudden jerk. According to the strength of the cord, its extensibility,
and the weight to be lifted, must be the nature of the upward pull in
order that the greatest possible velocity may be communicated without
injury to the cord or to the lifter's hand. This simple series of
experiments involves the essential principles of effective propulsion,
where, at least, great velocity is among the results to be attained.
Although, perhaps, at present, the public are disposed to consider the
University race from a sporting rather than from a scientific point of
view, yet it has long been admitted, even by the most ardent lovers
of rowing as a sport, that it has its scientific side. In a pamphlet
on the 'Principles of Rowing,' by 'Oarsmen,' written somewhere about
the year 1847,--it bears no date, but speaks of rowing as having first
appeared as a public amusement 11 years ago, and the first University
race on the Thames was rowed in 1836,--the writers urge that rowing
surely deserves to be called a scientific pursuit, and proceed to trace
out the 'main principles in virtue of which it claims a scientific
character.' These principles, which were generally considered sound
when they were originally enunciated, though even then they were
beginning to be to some degree questionable, have been quoted over and
over again since, or, if not verbally quoted, have been, in effect,
adopted by writers on rowing. The justice of some of them has caused
the entire set to be received without question, even by oarsmen who
in practice depart from several of them in a very marked degree. The
assumption has been that there is but one good rowing style, and that,
therefore, a style adopted and proved by practice to be the best in
the years 1836-1846 should be adopted as the best now. 'There is but
one style,' says one authority, 'and one alone,' he adds with some
redundancy. Now, in so far as river racing is almost always carried
on in boats of the same kind for each class--eight oars, four oars,
pairs, and sculls--it is in a sense true that there is but one racing
style. But even in river rowing, as distinguished from river racing,
there are more styles than one,--by which we mean more correct styles,
for, of course, there are multitudinous bad styles in every kind of
rowing. The style suitable for a racing boat moving at full speed
would not be suitable even for the same boat at starting, and would
be utterly unsuitable for a pleasure boat. We may remark, in passing,
that, however suitable tubbing practice may be several weeks before a
race, it is open to objection after a crew has settled into its racing
stroke. No one who understands rowing will assert that even the two
strongest members of either University crew _can_ row in the same style
in tub practice as in their eight at her full speed, or, seeing them,
will fail to perceive that they row entirely different strokes in the
tub and in the eight. Again, the style of rowing proved by practical
experience to be best in seaside racing is entirely different from the
style successful in river racing. Yet another style is essential to
success in races rowed in the heavier boats used by men-of-war's men.
And it will be admitted, we think, though no experiments have yet,
to our knowledge, been made in this direction, that if matches were
arranged among our best bargemen and lightermen we should see a mode
of pulling which would differ as markedly from the man-of-war's man's
strokes as that does from the stroke which O'Leary, of Folkestone,
rows, and this in turn from the style of the best London or University
oarsmen. So far as these last two styles are concerned, it should be
remembered that they have been put to the test in the most decisive
manner. The best London oarsmen have been repeatedly defeated in
seaside rowing (even in still weather), and the best seaside oarsmen
have been beaten in river rowing. It would be absurd to attribute this
to awkwardness in unfamiliar boats, for any good oarsman can very
soon row without awkwardness in any kind of boat. It was the style
which made the difference--the style only. On _à priori_ grounds,
then, we should expect to find the question whether the style approved
by 'Oarsmen' 30 years ago should be, as it is, the style constantly
recommended now-a-days depending simply on the question whether the
racing boat of our time is similar, so far as the requirements of
propulsion are concerned, to the old-fashioned racing boats, however
different in appearance the two kinds of boat may be. To assert this,
however, would be almost equivalent to asserting that there has been
no real improvement in the qualities of racing boats--nay, when one
considers the great advantages possessed, in some respects, by the old
fashioned boats and their much superior durability, we should have
to acknowledge that racing boats had deteriorated. No one will for a
moment assert this. We know that the racing boat of our time is not
only much lighter, but travels with much less resistance through the
water, maintains its velocity far better between the strokes, and can
be made with equal effort to go at least one-fifth faster than the old
fashioned racing boat. The antecedent probability is, then, that the
modern racing boat requires a mode of propulsion unlike that which was
approved in 1840 or thereabouts--requires, in fact, a style which in
those days would have been justly regarded as radically bad.
There is direct evidence from the results of many years of racing to
show that this difference really exists, as might be expected, though
the evidence may probably be questioned by those who maintain that
there is but one good rowing style. It is well known that the style
approved by 'Oarsmen' in the work above mentioned was first definitely
inculcated by Cambridge oarsmen. There is internal evidence in the
pamphlet itself (as where the miseries of the Lent races at Cambridge
are described) to show that some, and, therefore, probably all, who
took part in preparing the work were Cambridge men. Again, it is well
known that certainly until 1868, and perhaps later, the University crew
at Cambridge was 'coached' by an 'ancient mariner,' who, if not one
of the 'Oarsmen' and, as was generally reported, the actual writer
of the 'Principles of Rowing,' was unquestionably imbued with the old
fashioned doctrines. Now, of the six races rowed on the Thames in
the old fashioned racing boats, Cambridge won no less than five. The
Oxford crews, who rowed in a style more nearly resembling that now
rowed by the most successful crews (though scarcely ever inculcated
in verbal instructions), were not only beaten in every race save one,
but in three cases were beaten out of all reason. Half a minute was
the amount by which Cambridge won in 1845; but in 1836 (certainly
over a longer course) they won by one minute, in 1841 by one minute
and a quarter, and in 1839 by nearly two minutes. No wonder that when
outrigged boats came in Cambridge oarsmen were loth to modify a style
which had gained them so many and such striking successes. Nor did it
greatly matter, when this happened in 1846, whether the style of rowing
was modified or not. The first specimens of outrigged racing boats
occupied a sort of half-way position between the old-fashioned inrigged
craft and the exceedingly light, keelless boats now used. Thus, during
the seven races rowed in the earlier form of outrigged boats, success
was pretty equally divided between Oxford and Cambridge. In one race
Oxford won on a foul; of the other six Cambridge won three, and Oxford
also won three. But since the present form of racing boat was adopted
(in 1857) Oxford has been almost as successful as Cambridge had been
in the first nine or ten races. In 1857 Oxford won easily; in 1858
Cambridge won, but the stroke of the Oxford boat could use but half
his strength, the forward or working thole of his rowlocks having been
bent outwards by a wave which caught his oar before the race began.
(The outriggers and rowlocks were shown to me at Searle's boat-house
a few days after the race, and there could be no question that the
chances of the Oxford boat must have been seriously impaired by the
accident.) In 1859 Cambridge sank, and, though she was four lengths
behind when this happened, there can be little doubt she would have
won but for the original cause of the disaster--a wave which had half
filled the Cambridge boat as she was turning to take her place at the
starting-point. In 1860 Cambridge won by one length only. Then, as
everyone remembers, there followed nine successive Oxford victories,
some of which were of the most hollow kind. Cambridge then gave up the
style to which she had so long been faithful. One of the ablest of
the Oxford oarsmen, who was, however, connected in some degree with
Cambridge, trained and coached the Cambridge crew of 1870, the stroke
of which, it should be mentioned, was proficient in the correct style
before he went to Cambridge. That year and for the four next years
Cambridge won, though never in the hollow fashion in which Oxford had
won the victories of 1861, 1862, 1863, 1864, and 1868. The lead of
Oxford at the finish of these five races averaged over nine lengths,
while the lead of Cambridge in the five races of 1870-74 averaged
little over two lengths. In 1875 Oxford won by ten lengths, Cambridge
in 1876 by five. In 1877 occurred the celebrated dead heat; but before
bow's oar broke Oxford had won 'bar accidents.' In 1878 Oxford won,
and again by ten lengths. Of the 25 races actually rowed to a finish
(excluding the dead heat) since outriggers were introduced, Oxford has
won 14, Cambridge 11; of the 19 so rowed out since the true modern
racing boat was used, Oxford has won 11 and Cambridge 8. The difference
is sufficient in either case to show (the numbers being considerable)
that there is a true difference of style, the style of Oxford being
the better. But when we consider how the victories have been won this
comes out still more clearly. Making due estimate of the number of
lengths corresponding to so many seconds of time difference (where
the result of a race is so indicated in the list), for which purpose
it is sufficient to note that as many seconds as the race itself has
occupied minutes are equivalent to about 6-1/2 lengths, we find for the
11 victories of Cambridge since 1846 about 30-1/4 lengths, and for the
14 rowed-out victories of Oxford about 106-1/2 lengths--the Cambridge
average lead being thus found to be less than three lengths, while the
Oxford average lead at the finish has been close on eight lengths.
The difference cannot reasonably be assigned to any cause which
was in operation when Cambridge had the larger share of victories.
Nearly every cause which has been commonly assigned, including the
unquestionably inferior arrangements for college racing at Cambridge,
falls into this category. There can be very little doubt that the
true explanation, as well of Cambridge success before 1850 as of
Oxford success since then, resides in the circumstance that the two
Universities have in the main adopted throughout the whole series of
contests two different styles--each style excellent in itself, but the
Cambridge as unquestionably superior to the Oxford for the heavier
kinds of river boats as the Oxford style is superior to the Cambridge
for the boats now actually used in river races. What the difference in
the two styles is I shall now briefly indicate.
I am satisfied that the essential excellence of the old fashioned
racing style as used in the old fashioned boats becomes an inherent
defect in the same style as used in modern racing boats. I refer to the
principle involved in the words italicised (by myself) in the following
quotation from 'Principles of Rowing':--'The instant the oar touches
the water the arms and body begin to fall backwards, the _former
continuing at their full stretch till the back is perpendicular_. They
are then bent, the elbows being brought close past the sides, till
the hands, which are now brought home sharply, strike the body above
the lowest ribs.' Such was the stroke that brave old Coombes used to
teach, and such was the stroke by which, time and again, races were won
before 1850. But in proportion as the racing boat has been improved,
both by diminution of weight and resistance and by change of leverage,
the necessity has increased for a more energetic application of the
oarsman's power. A stroke which resulted in mere jerking, injurious
to the rower and not adding to speed, in the old racing boats, is
absolutely essential to the effective propulsion of the modern racing
boat, when once at least full speed has been attained, for before this
the old fashioned long drag with lightning feather is as useful now as
ever. Now, no one who has watched a really good Oxford crew at full
speed can fail to observe the way in which the oars literally smite
the water at the beginning of each stroke. No one who considers the
velocity with which they must move to give this sledge-hammer stroke
at the beginning can fail to perceive that the body alone cannot give
this velocity of impulse in the first part of the stroke. There is only
one way in which it can be attained, and that is by making the arms
work from the beginning, not merely in the sense in which they may
be said to work when continuing at their full stretch, but by actual
and energetic contraction. In the Cambridge style arms and body only
work together after the back is perpendicular; in the Oxford style
they work together from the beginning. The result is that by the time
the Oxford oars man has brought his back perpendicular his stroke is
finished; whereas the Cambridge oarsman has still to give that drag
at the end which used to be so much esteemed, and still is justly
esteemed, by sailors for sea-racing. The oar of the Oxford rower is a
much shorter time in the water, simply because it is propelled through
the water with far greater, or rather with much more concentrated
energy. The Oxford stroke, again, is necessarily a few inches shorter.
For as Cambridge men go as far forward and swing further backward,
it stands to reason that they get a little more length. But they get
this additional length at the cost of a great strain on the abdominal
muscles, and with no proportional effect. A very strong crew which
can maintain the long, dragging stroke with the lightning feather
from beginning to end may win, as Cambridge men have won, but only
because of their superior strength, not by virtue of that lift at the
end, which wearies the most stalwart, causes sluggish disengagement
of the hands, and in a long race has often caused a powerful crew to
be beaten by weaker men rowing in a more scientific manner. It is not
impossible, now that the Oxford crew have had set them the true Oxford
stroke that we may have an opportunity of witnessing something of this
kind on Saturday, though the manifest superiority of the Cambridge
crew in strength and the lateness of the change in the Oxford boat are
unfavourable to the chances of the dark blue. To return to the point
from which we started. The just style of propulsion for each class of
boat is a matter to be determined on scientific principles. There is
no real conflict between theory and practice in this matter. Every
change which has tended to increase the speed of racing boats has (like
the changes in Poncelet's experiment) rendered necessary an increased
energy, or, as one may say, an increased intensity of propulsion.
_ARTIFICIAL SOMNAMBULISM._
Rather more than a quarter of a century ago two Americans visited
London, who called themselves professors of Electro-Biology, and
claimed the power of 'subjugating the most determined wills, paralysing
the strongest muscles, preventing the evidence of the senses,
destroying the memory of the most familiar events or of the most
recent occurrences, inducing obedience to any command, and making an
individual believe himself transformed into any one else.' All this
and more was to be effected, they said, by the action of a small disc
of zinc and copper held in the hand of the 'subject,' and steadily
gazed at by him, 'so as to concentrate the electro-magnetic action.'
The pretensions of these professors received before long a shock as
decisive as that which overthrew the credit of the professors of
animal magnetism when Haygarth and Falconer successfully substituted
wooden tractors for the metallic tractors which had been supposed
to convey the magnetic fluid. In 1851, Mr. Braid, a Scotch surgeon,
who had witnessed some of the exhibitions of the electro-biologists,
conceived the idea that the phenomena were not due to any special
qualities possessed by the discs of zinc and copper, but simply to
the fixed look of the 'subject' and the entire abstraction of his
attention. The same explanation applied to the so-called 'magnetic
passes' of the mesmerists. The monotonous manipulation of the operator
produced the same effect as the fixed stare of the 'subject.' He showed
by his experiments that no magnetiser, with his imaginary secret
agents or fluids, is in the least wanted; but that the subjects can
place themselves in the same condition as the supposed subjects of
electro-biological influences by simply gazing fixedly at some object
for a long time with fixed attention.
The condition thus superinduced is not hypnotism, or artificial
somnambulism, properly so called. 'The electro-biological' condition
may be regarded as simply a kind of reverie or abstraction artificially
produced. But Braid discovered that a more perfect control might be
obtained over 'subjects,' and a condition resembling that of the
sleepwalker artificially induced, by modifying the method of fixing the
attention. Instead of directing the subject's gaze upon a bright object
placed at a considerable distance from the eyes, so that no effect
was required to concentrate vision upon it, he placed a bright object
somewhat above and in front of the eyes at so short a distance that
the convergence of their axes upon it was accompanied with sufficient
effect to produce even a slight amount of pain. The condition to which
the 'subjects' of this new method were reduced was markedly different
from the ordinary 'electro-biological' state. Thus on one occasion, in
the presence of 800 persons, fourteen men were experimented upon. 'All
began the experiment at the same time; the former with their eyes fixed
upon a projecting cork, placed securely on their foreheads; the others
at their own will gazed steadily at certain points in the direction of
the audience. In the course of ten minutes the eyelids of these ten
persons had involuntarily closed. With some, consciousness remained;
others were in catalepsy, and entirely insensible to being stuck with
needles; and others on awakening knew absolutely nothing of what had
taken place during their sleep.' The other four simply passed into
the ordinary condition of electro-biologised 'subjects,' retaining
the recollection of all that happened to them while in the state of
artificial abstraction or reverie.
Dr. Carpenter, in that most interesting work of his, 'Mental
Physiology,' thus describes the state of hypnotism:--'The process is
of the same kind as that employed for the induction of the "biological"
state; the only difference lying in the _greater intensity_ of the
gaze, and in the more complete concentration of will upon the direction
of the eyes, which the nearer approximation of the object requires
for the maintenance of the convergence. In hypnotism, as in ordinary
somnambulism, no remembrance whatever is preserved in the waking state
of anything that may have occurred during its continuance; although the
previous train of thought may be taken up and continued uninterruptedly
on the next occasion that the hypnotism is induced. And when the mind
is not excited to activity by the stimulus of external impressions, the
hypnotised subject appears to be profoundly asleep; a state of complete
torpor, in fact, being usually the first result of the process, and
any subsequent manifestation of activity being procurable only by
the prompting of the operator. The hypnotised subject, too, rarely
opens his eyes; his bodily movements are usually slow; his mental
operations require a considerable time in their performance; and there
is altogether an appearance of heaviness about him, which contrasts
strongly with the comparatively wide-awake air of him who has not
passed beyond the ordinary "biological" state.'
We must note, however, in passing, that the condition of complete
hypnotism had been obtained in several instances by some of the
earlier experimenters in animal magnetism. One remarkable instance
was communicated to the surgical section of the French Academy on
April 16, 1829, by Jules Cloquet. Two meetings were entirely devoted
to its investigation. The following account presents all the chief
points of the case, surgical details being entirely omitted, however,
as not necessary for our present purpose:--A lady, aged sixty-four,
consulted M. Cloquet on April 8, 1829, on account of an ulcerated
cancer of the right breast which had continued, gradually growing
worse, during several years. M. Chapelain, the physician attending the
lady, had 'magnetised' her for some months, producing no remedial
effects, but only a very profound sleep or torpor, during which all
sensibility seemed to be annihilated, while the ideas retained all
their clearness. He proposed to M. Cloquet to operate upon her while
she was in this state of torpor, and, the latter, considering the
operation the only means of saving her life, consented. The two doctors
do not appear to have been troubled by any scruples as to their right
thus to conduct an operation to which, when in her normal condition,
the patient strenuously objected. It sufficed for them that when
they had put her to sleep artificially, she could be persuaded to
submit to it. On the appointed day M. Cloquet found the patient ready
'dressed and seated in an elbow-chair, in the attitude of a person
enjoying a quiet natural sleep.' In reality, however, she was in the
somnambulistic state, and talked calmly of the operation. During the
whole time that the operation lasted--from ten to twelve minutes--she
continued to converse quietly with M. Cloquet, 'and did not exhibit
the slightest sign of sensibility. There was no motion of the limbs
or of the features, no change in the respiration nor in the voice; no
motions even in the pulse. The patient continued in the same state
of automatic indifference and impassibility in which she had been
some minutes before the operation.' For forty-eight hours after this,
the patient remained in the somnambulistic state, showing no sign of
pain during the subsequent dressing of the wound. When awakened from
this prolonged sleep she had no recollection of what had passed in
the interval; 'but on being informed of the operation, and seeing her
children around her, she experienced a very lively emotion which the
"magnetiser" checked by immediately setting her asleep.' Certainly none
of the hypnotised 'subjects' of Mr. Braid's experiments showed more
complete abstraction from their normal condition than this lady; and
other cases cited in Bertrand's work, 'Le Magnetisme Animal en France'
(1826), are almost equally remarkable. As it does not appear that in
any of these cases Braid's method of producing hypnotism by causing
the eyes, or rather their optical axes, to be converged upon a point,
was adopted, we must conclude that this part of the method is not
absolutely essential to success. Indeed, the circumstance that in some
of Braid's public experiments numbers of the audience became hypnotised
without his knowledge, shows that the more susceptible 'subjects' do
not require to contemplate a point near and slightly above the eyes,
but may be put into the true hypnotic state by methods which, with the
less susceptible, produce only the electro-biological condition.
It will be well, however, to inquire somewhat carefully into this
point. My present object, I would note, is not merely to indicate the
remarkable nature of the phenomena of hypnotism, but to consider these
phenomena with direct reference to their probable cause. It may not be
possible to obtain a satisfactory explanation of them. But it is better
to view them as phenomena to be accounted for than merely as surprising
but utterly inexplicable circumstances.
Now we have fortunately the means of determining the effect of the
physical relations involved in these experiments, apart from those
which are chiefly due to imagination. For animals can be hypnotised,
and the conditions necessary for this effect to be fully produced have
been ascertained.
The most familiar experiment of this sort is sometimes known as
Kircher's. Let the feet of a hen be tied together (though this is not
necessary in all cases), and the hen placed on a level surface. Then if
the body of the hen is gently pressed down, the head extended with the
beak pointing downwards, touching the surface on which the hen stands,
and a chalk mark is drawn slowly along the surface, from the tip of the
beak in a line extending directly from the bird's eye, it is found that
the hen will remain for a considerable time perfectly still, though
left quite free to move. She is, in fact, hypnotised.
We have now to inquire what parts of the process just described are
effective in producing the hypnotic condition, or whether all are
essential to success in the experiment.
In the first place, the fastening of the feet may be dispensed
with. But it has its influence, and makes the experiment easier. An
explanation, or rather an illustration, of its effect is afforded by a
singular and interesting experiment devised by Lewissohn of Berlin:--If
a frog is placed on its back, it immediately, when the hand which had
held it is removed, turns over and escapes. But if the two fore-legs
are tied with a string, the frog, when placed on its back, breathes
heavily but is otherwise quite motionless, and does not make the least
attempt to escape, even when the experimenter tries to move it. 'It
is as though,' say Czermak, describing the experiment as performed
by himself, 'its small amount of reasoning power had been charmed
away, or else that it slept with open eyes. Now I press upon the
cutaneous nerves of the frog, while I loosen and remove the threads
on the fore-legs. Still the animal remains motionless upon its back,
in consequence of some remaining after-effect; at last, however, it
returns to itself, turns over, and quickly escapes.'
Thus far the idea suggested is that the animal is so affected by the
cutaneous pressure as to suppose itself tied and therefore unable
to move. In other words, this experiment suggests that imagination
acts on animals as on men, only in a different degree. I may cite
here a curious case which I once noticed and have never been able to
understand, though it seems to suggest the influence of imagination on
an animal one would hardly suspect of being at all under the influence
of any but purely physical influences. Hearing a noise as of a cat
leaping down from a pantry window which looked out on an enclosed yard,
I went directly into the yard, and there saw a strange cat running
off with a fish she had stolen. She was at the moment leaping on to
a bin, from the top of which, by another very easy leap, she could
get on to the wall enclosing the yard, and so escape. With the idea
rather of frightening her than of hurting her (does one missile out of
a hundred flung at cats ever hit them?) I threw at the thief a small
piece of wood which I had in my hand at the moment. It struck the
wall above her just as she was going to leap to the top of the wall,
and it fell, without touching her, between her and the wall. To my
surprise, she stood perfectly still, looking at the piece of wood; her
mouth, from which the fish had fallen, remaining open, and her whole
attitude expressing stupid wonder. I make no doubt I could have taken
her prisoner, or struck her heavily, if I had wished, for she made no
effort to escape, until, with a parlour broom which stood by, I pushed
her along the top of the bin towards the wall, when she seemed suddenly
to arouse herself, and leaping to the top of the wall she made off.
My wife witnessed the last scene of this curious little comedy. In
fact, it was chiefly, perhaps, because she pleaded for mercy on 'the
poor thing' that the soft end of the broom alone came into operation;
for, though not altogether agreeing with the Count of Rousillon that
anything can be endured before a cat, I did not at the moment regard
that particular cat with special favour.
The extension of the neck and depression of the head, in the experiment
with the hen, have no special significance, for Czermak has been able
to produce the same phenomena of hypnotism without them, and has failed
to produce the hypnotic effect on pigeons when attending to this point,
and in other respects proceeding as nearly as possible in the same
way as with hens. 'With the hens,' he says, 'I often hung a piece of
twine, or a small piece of wood, directly over their crests, so that
the end fell before their eyes. The hens not only remained perfectly
motionless, but closed their eyes, and slept with their heads sinking
until they came in contact with the table. Before falling asleep,
the hens' heads can be either pressed down or raised up, and they
will remain in this position as if they were pieces of wax. That is,
however, a symptom of a cataleptic condition, such as is seen in human
beings, under certain pathological conditions of the nervous system.'
On the other hand, repeated experiments convinced Czermak that the
pressure on the animal as it is held is of primary importance. It
is frequently the case, he says, that a hen, which for a minute has
been in a motionless state, caused by simply extending the neck and
depressing the head, awakes and flies away, but on being caught again
immediately, she can be placed once more in the condition of lethargy,
if we place the animal in a squatting position, and overcome with
gentle force the resistance of the muscles, by firmly placing the hand
upon its back. During the slow and measured suppression, one often
perceives an extremely remarkable position of the head and neck, which
are left entirely free. The head remains as if held by an invisible
hand in its proper place, the neck being stretched out of proportion,
while the body by degrees is pushed downwards. If the animal is thus
left entirely free, it remains for a minute or so in this peculiar
condition with wide-open staring eyes. 'Here,' as Czermak remarks,
'the actual circumstances are only the effect of the emotion which the
nerves of the skin excite, and the gentle force which overcomes the
animal's resistance. Certainly the creature a short time before had
been in a condition of immobility, and might have retained some special
inclination to fall back into the same, although the awakening, flight,
and recapture, together with the refreshment given to the nervous
system, are intermediate circumstances.' Similar experiments are best
made upon small birds. Now, it is well known to bird fanciers that
goldfinches, canary-birds, &c. can be made to remain motionless for
some time by simply holding them firmly for a moment and then letting
them go. 'Here, in my hand,' said Czermak, in his lecture, 'is a timid
bird, just brought from market. If I place it on its back, and hold its
head with my left hand, keeping it still for a few seconds, it will
lie perfectly motionless after I have removed my hands, as if charmed,
breathing heavily, and without making any attempt to change its
position or to fly away.' ('Two of the birds,' says the report, 'were
treated in this manner without effect; but the third, a siskin, fell
into a sleeping condition, and remained completely immovable on its
back, until pushed with a glass tube, when it awoke and flew actively
around the room.')
Also when a bird is in a sitting position, and the head is pressed
slightly back, the bird falls into a sleeping condition, even though
the eyes had been open. 'I have often noticed,' says Czermak, 'that the
birds under these circumstances close their eyes for a few minutes or
even a quarter of an hour, and are more or less fast asleep.'
Lastly, as to the chalk-line in Kircher's experiment. Czermak found,
as already said, that pigeons do not become motionless, as happens to
hens, if merely held firmly in the hand, and their heads and necks
pressed gently on the table. Nor can they be hypnotised like small
birds in the experiment last mentioned. 'That is,' he says, 'I held
them with a thumb placed on each side of the head, which I bent over
a little, while the other hand held the body gently pressed down upon
the table; but even this treatment, which has such an effect on little
birds, did not seem to succeed at first with the pigeons: almost always
they flew away as soon as I liberated them and entirely removed my
hands.' But he presently noticed that the short time during which the
pigeons remained quiet lengthened considerably when the finger only of
the hand which held the head was removed. Removing the hand holding
the body made no difference, but retaining the other hand near the
bird's head, the hand made all the difference in the world. Pursuing
the line of research thus indicated, Czermak found to his astonishment
that the fixing of the pigeon's look on the finger placed before its
eyes was the secret of the matter. In order to determine the question
still more clearly, he tried the experiment on a pigeon which he had
clasped firmly by the body in his left hand, but whose neck and head
were perfectly free. 'I held one finger of my right hand steadily
before the top of its beak,--and what did I see? The first pigeon with
which I made this attempt remained rigid and motionless, as if bound,
for several minutes, before the outstretched forefinger of my right
hand! Yes, I could take my left hand, with which I had held the bird,
and again touch the pigeon without waking it up; the animal remained in
the same position while I held my outstretched finger still pointing
towards the beak.' 'The lecturer,' says the report, 'demonstrated
this experiment in the most successful manner with a pigeon which was
brought to him.'
Yet it is to be noticed that among animals as among men, different
degrees of subjectivity exist. 'Individual inward relations,' says
Czermak, 'as well as outward conditions, must necessarily exercise some
disturbing influence, whether the animal will give itself up to the
requisite exertions of certain parts of its brain with more or less
inclination or otherwise. We often see, for example, that a pigeon
endeavours to escape from confinement by a quick turning of its head
from side to side. In following these singular and characteristic
movements of the head and neck, with the finger held before the bird,
one either gains his point, or else makes the pigeon so perplexed and
excited that it at last becomes quiet, so that, if it is held firmly
by the body and head, it can be forced gently down upon the table.
As Schopenhauer says of sleeping, "The brain must bite." I will also
mention here, by the way, that a tame parrot, which I have in my house,
can be placed in this sleepy condition by simply holding the finger
steadily before the top of its beak.'
I may cite here a singular illustration of the effect of perplexity
in the case of a creature in all other respects much more naturally
circumstanced than the hens, pigeons, and small birds of Czermak's
experiments. In the spring of 1859, when I was an undergraduate at
Cambridge, I and a friend of mine were in canoes on the part of the
Cam which flows through the College grounds. Here there are many ducks
and a few swans. It occurred to us, not, I fear, from any special
scientific spirit, but as a matter of curiosity, to inquire whether it
was possible to pass over a duck in a canoe. Of course on the approach
of either canoe a duck would try to get out of the way on one side or
the other; but on the course of the canoe being rapidly changed, the
duck would have to change his course. Then the canoe's course would
again be changed, so as to compel the duck to try the other side. The
canoe drawing all the time nearer, and her changes of course being made
very lightly and in quicker and quicker alternation as she approached,
the duck would generally get bewildered, and finally would allow the
canoe to pass over him, gently pressing him under water in its course.
The process, in fact, was a sort of mild keelhauling. The absolute
rigidity of body and the dull stupid stare with which some of the
ducks met their fate seems to me (_now_: I was not in 1859 familiar
with the phenomena of hypnotism) to suggest that the effect was to be
explained as Czermak explains the hypnotism of the pigeons on which he
experimented.
We shall be better able now to understand the phenomena of artificial
somnambulism in the case of human beings. If the circumstances observed
by Kircher, Czermak, Lewissohn, and others, suggest, as I think they
do, that animal hypnotism is a form of the phenomenon sometimes called
fascination, we may be led to regard the possibility of artificial
somnambulism in men as a survival of a property playing in all
probability an important and valuable part in the economy of animal
life. It is in this direction, at present, that the evidence seems to
tend.
The most remarkable circumstance about the completely hypnotised
subject is the seemingly complete control of the will of the 'subject'
and even of his opinions. Even the mere suggestions of the operator,
not expressed verbally or by signs, but by movements imparted to the
body of the subject, are at once responded to, as though, to use Dr.
Garth Wilkinson's expression, the _whole man_ were given to each
perception. Thus, 'if the hand be placed,' says Dr. Carpenter, 'upon
the top of the head, the somnambulist will frequently, of his own
accord, draw up his body to its fullest height, and throw his head
slightly back; his countenance then assumes an expression of the
most lofty pride, and his whole mind is obviously possessed by that
feeling. When the first action does not of itself call forth the rest,
it is sufficient for the operator to straighten the legs and spine,
and to throw the head somewhat back, to arouse that feeling and the
corresponding expression to its fullest intensity. During the most
complete domination of this emotion, let the head be bent forward,
and the body and limbs gently flexed; and the most profound humility
then instantaneously takes its place.' Of course in some cases we may
well believe that the expressions thus described by Dr. Carpenter have
been simulated by the subject. But there can be no reason to doubt
the reality of the operator's control in many cases. Dr. Carpenter
says that he has not only been an eye-witness of them on various
occasions, but that he places full reliance on the testimony of an
intelligent friend, who submitted himself to Mr. Braid's manipulations,
but retained sufficient self-consciousness and voluntary power to
endeavour to exercise some resistance to their influence at the time,
and subsequently to retrace his course of thought and feeling. 'This
gentleman declares,' says Dr. Carpenter, 'that, although accustomed
to the study of character and to self-observation, he could not
have conceived that the whole mental state should have undergone so
instantaneous and complete a metamorphosis, as he remembers it to
have done, when his head and body were bent forward in the attitude
of humility, after having been drawn to their full height in that of
self-esteem.'
A most graphic description of the phenomena of hypnotism is given by
Dr. Garth Wilkinson:--'The preliminary state is that of abstraction,
produced by fixed gaze upon some unexciting and empty thing (for
poverty of object engenders abstraction), and this abstraction is the
logical premiss of what follows. Abstraction tends to become more and
more abstract, narrower and narrower; it tends to unity and afterwards
to nullity. There, then, the patient is, at the summit of attention,
with no object left, a mere statue of attention, a listening, expectant
life; a perfectly undistracted faculty, dreaming of a lessening and
lessening mathematical point: the end of his mind sharpened away to
nothing. What happens? Any sensation that appeals is met by this
brilliant attention, and receives its diamond glare; being perceived
with a force of leisure of which our distracted life affords only the
rudiments. External influences are sensated, sympathised with, to an
extraordinary degree; harmonious music sways the body into graces the
most affecting; discords jars it, as though they would tear it limb
from limb. Cold and heat are perceived with similar exaltation; so
also smells and touches. In short, _the whole man appears to be given
to each perception_. The body trembles like down with the wafts of the
atmosphere; the world plays upon it as upon a spiritual instrument
finely attuned.'
This state, which may be called the natural hypnotic state, may be
artificially modified. 'The power of suggestion over the patient,' says
Dr. Garth Wilkinson, 'is excessive. If you say, "What animal is it?"
the patient will tell you it is a lamb, or a rabbit, or any other.
"Does he see it?" "Yes." "What animal is it _now_?" putting depth and
gloom into the tone of _now_, and thereby suggesting a difference.
"Oh!" with a shudder, "it is a wolf!" "What colour is it?" still
glooming the phrase. "Black." "What colour is it now?" giving the _now_
a cheerful air. "Oh! a beautiful blue!" (rather an unusual colour for a
wolf, I would suggest), spoken with the utmost delight (and no wonder!
especially if the hypnotic subject were a naturalist). And so you lead
the subject through any dreams you please, by variations of questions
and of inflections of the voice! and _he sees and feels all as real_.'
We have seen how the patient's mind can be influenced by changing the
posture of his body. Dr. Wilkinson gives very remarkable evidence on
this point. 'Double his fist and pull up his arm, if you dare,' he
says, of the subject, 'for you will have the strength of your ribs
rudely tested. Put him on his knees and clasp his hands, and the
saints and devotees of the artists will pale before the trueness of his
devout actings. Raise his head while in prayer, and his lips pour forth
exulting glorifications, as he sees heaven opened, and the majesty of
God raising him to his place; then in a moment depress the head, and he
is in dust and ashes, an unworthy sinner, with the pit of hell yawning
at his feet. Or compress the forehead, so as to wrinkle it vertically,
and thorny-toothed clouds contract in from the very horizon' (in the
subject's imagination, it will be understood); 'and what is remarkable,
the smallest pinch and wrinkle, such as will lie between your nipping
nails, is sufficient nucleus to crystallise the man into that shape,
and to make him all foreboding, as, again, the smallest expansion in a
moment brings the opposite state, with a full breathing of delight.'
Some will perhaps think the next instance the most remarkable of all,
perfectly natural though one half of the performance may have been. The
subject being a young lady, the operator asks whether she or another
is the prettier, raising her head as he puts the question. 'Observe,'
says Dr. Wilkinson, 'the inexpressible hauteur, and the puff sneers let
off from the lips' (see Darwin's treatise on the 'Expression of the
Emotions,' plate IV. i, and plate V. i) 'which indicate a conclusion
too certain to need utterance. Depress the head, and repeat the
question, and mark the self-abasement with which she now says "_She
is_," as hardly worthy to make the comparison.'
In this state, in fact, 'whatever posture of any passion is induced,
the passion comes into it at once, and dramatises the body accordingly.'
It might seem that there must of necessity be some degree of
exaggeration in this description, simply because the power of
adequately expressing any given emotion is not possessed by all. Some
can in a moment bring any expression into the face, or even simulate
at once the expression and the aspect of another person, while many
persons, probably most, possess scarcely any power of the sort, and
fail ridiculously even in attempting to reproduce the expressions
corresponding to the commonest emotions. But it is abundantly clear
that the hypnotised subject possesses for the time being abnormal
powers. No doubt this is due to the circumstance that for the time
being 'the whole man is given to each perception.' The stories
illustrative of this peculiarity of the hypnotised state are so
remarkable that they have been rejected as utterly incredible by many
who are not acquainted with the amount of evidence we have upon this
point.
The instances above cited by Dr. Garth Wilkinson, remarkable though
they may be, are surpassed altogether in interest by a case which
Dr. Carpenter mentions,--of a factory girl, whose musical powers had
received little cultivation, and who could scarcely speak her own
language correctly, who nevertheless exactly imitated both the words
and the music of vocal performances by Jenny Lind. Dr. Carpenter was
assured by witnesses in whom he could place implicit reliance, that
this girl, in the hypnotised state, followed the Swedish nightingale's
songs in different languages 'so instantaneously and correctly, as to
both words and music, that it was difficult to distinguish the two
voices. In order to test the powers of the somnambulist to the utmost,
Mademoiselle Lind extemporised a long and elaborate chromatic exercise,
which the girl imitated with no less precision, though in her waking
state she durst not even attempt anything of the sort.'
The exaltation of the senses of hypnotised subjects is an equally
wonderful phenomenon. Dr. Carpenter relates many very remarkable
instances as occurring within his own experience. He has 'known a
youth, in the hypnotised state,' he says, 'to find out, by the sense of
smell, the owner of a glove which was placed in his hand, from amongst
a party of more than sixty persons, scenting at each of them one after
the other until he came to the right individual. In another case, the
owner of a ring was unhesitatingly found out from amongst a company
of twelve, the ring having been withdrawn from the finger before the
somnambule was introduced.' The sense of touch has, in other cases,
been singularly intensified, insomuch that slight differences of heat,
which to ordinary feeling were quite inappreciable, would be at once
detected, while such differences as can be but just perceived in the
ordinary state would produce intense distress.
In some respects, the increase of muscular power, or rather of the
power of special muscles, is even more striking, because it is commonly
supposed by most persons that the muscular power depends entirely on
the size and quality of the muscles, the state of health, and like
conditions, not on the imagination. Of course every one knows that the
muscles are capable of greater efforts when the mind is much excited
by fear and other emotions. But the general idea is, I think, that
whatever the body is capable of doing under circumstances of great
excitement, it is in reality capable of doing at all times if only
a resolute effort is made. Nor is it commonly supposed that a very
wide difference exists between the greatest efforts of the body under
excitement and those of which it is ordinarily capable. Now, the
condition of the hypnotised subject is certainly not one of excitement.
The attempts which he is directed to make are influenced only by the
idea that he _can_ do what he is told, not that he _must_ do so. When a
man pursued by a bull leaps over a wall which under ordinary conditions
he would not even think of climbing, we can understand that he only
does, because he must, what if he liked he could do at any time. But
if a man who had been making his best efforts in jumping, cleared
only a height of four feet, and presently being told to jump over an
eight-feet wall, cleared that height with apparent ease, we should be
disposed to regard the feat as savouring of the miraculous.
Now Dr. Carpenter saw one of Mr. Braid's hypnotised subjects--a man so
remarkable for the poverty of his physical development that he had not
for many years ventured to lift up a weight of twenty pounds in his
ordinary state--take up a quarter of a hundredweight upon his little
finger, and swing it round his head with the utmost apparent ease, on
being told that it was as light as a feather. 'On another occasion
he lifted a half-hundredweight on the last joint of his forefinger
as high as his knee.' The personal character of the man placed him
above all suspicion of deceit, in the opinion of those who best knew
him; and as Dr. Carpenter acutely remarks, 'the impossibility of any
trickery in such a case would be evident to the educated eye, since,
if he had practised such feats (which very few, even of the strongest
men could accomplish without practice), the effect would have made
itself visible in his muscular development.' 'Consequently,' he adds,
'when the same individual afterwards declared himself unable, with the
greatest effort, to lift a handkerchief from the table, after having
been assured that he could not possibly move it, there was no reason
for questioning the truth of his conviction, based as this was upon
the same kind of suggestion as that by which he had been just before
prompted to what seemed an otherwise impossible action.'
The explanation of this and the preceding cases cannot be mistaken by
physiologists, and is very important in its bearing on the phenomena
of hypnotism generally, at once involving an interpretation of the
whole series of phenomena, and suggesting other relations not as yet
illustrated experimentally. It is well known that in our ordinary use
of any muscles we employ but a small part of the muscle at any given
moment. What the muscle is actually capable of is shown in convulsive
contractions, in which far more force is put forth than the strongest
effort of the will could call into play. We explain, then, the seeming
increase of strength in any set of muscles during the hypnotic state as
due to the concentration of the subject's will in an abnormal manner,
or to an abnormal degree, on that set of muscles. In a similar way,
the great increase of certain powers of perception may be explained
as due to the concentration of the will upon the corresponding parts
of the nervous system. In like manner, the will may be directed so
entirely to the operations necessary for the performances of difficult
feats, that the hypnotised or somnambulistic subject may be able to
accomplish what in his ordinary condition would be impossible or
even utterly appalling to him. Thus sleep-walkers (whose condition
precisely resembles that of the artificially hypnotised, except that
the suggestions they experience come from contact with inanimate
objects, instead of being aroused by the actions of another person)
'can clamber walls and roofs, traverse narrow planks, step firmly along
high parapets, and perform other feats which they would shrink from
attempting in their waking state.' This is simply, as Dr. Carpenter
points out, because they are _not distracted_ by the sense of danger
which their vision would call up, from concentrating their exclusive
attention on the guidance afforded by their muscular sense.'
But the most remarkable and suggestive of all the facts known
respecting hypnotism is the influence which can by its means be
brought to bear upon special parts or functions of the body. We know
that imagination will hasten or retard certain processes commonly
regarded as involuntary (indeed, the influence of imagination is itself
in great degree involuntary). We know further that in some cases
imagination will do much more than this, as in the familiar cases of
the disappearance of warts under the supposed influence of charms,
the cure of scrofula at a touch, and hundreds of well-attested cases
of so-called miraculous cures. But although the actual cases of the
curative influence obtained over hypnotised patients may not be in
reality more striking than some of these, yet they are more suggestive
at any rate to ordinary minds, because they are known not to be the
result of any charm or miraculous interference, but to be due to simply
natural processes initiated by natural though unfamiliar means.
Take, for instance, such a case as the following, related by Dr.
Carpenter (who has himself witnessed many remarkable cases of
hypnotic cure):--'A female relative of Mr. Braid's was the subject
of a severe rheumatic fever, during the course of which the left eye
became seriously implicated, so that after the inflammatory action
had passed away, there was an opacity over more than one half of the
cornea, which not only prevented distinct vision, but occasioned
an annoying disfigurement. Having placed herself under Mr. Braid's
hypnotic treatment for the relief of violent pain in her arm and
shoulder, she found, to the surprise alike of herself and Mr. Braid,
that her sight began to improve very perceptibly. The operation was
therefore continued daily; and in a very short time the cornea became
so transparent that close inspection was required to discover any
remains of the opacity.' On this, Carpenter remarks that he has known
other cases in which secretions that had been morbidly suspended have
been reinduced by this process; and is satisfied that, if applied
with skill and discrimination, it would take rank as one of the most
potent methods of treatment which the physician has at his command. He
adds that 'the channel of influence is obviously the system of nerves
which regulates the secretions--nerves which, though not under direct
subjection to the will, are peculiarly affected by emotional states.'
I may remark, in passing, that nerves which are not ordinarily under
the influence of the will, but whose office would be to direct muscular
movements if only the will could influence them, may by persistent
attention become obedient to the will. When I was last in New York,
I met a gentleman who gave me a long and most interesting account
of certain experiments which he had made on himself. The account
was not forced on me, the reader must understand, but was elicited
by questions suggested by one or two remarkable facts which he had
casually mentioned as falling within his experience. I had only his
own word for much that he told me, and some may perhaps consider that
there was very little truth in the narrative. I may pause here to make
some remarks by the way, on the traits of truthful and untruthful
persons. I believe very slight powers of observation are necessary to
detect want of veracity in any man, though absence of veracity in any
particular story may not be easily detected or established. I am not
one of those who believe every story they hear, and trust in every one
they meet. But I have noticed one or two features by which the habitual
teller of untruths may be detected very readily, as may also one who,
without telling actual falsehoods, tries to heighten the effect of
any story he may have to tell, by strengthening all the particulars.
My experience in this respect is unlike Dickens's, who believed, and
indeed found, that a man whom on first seeing he distrusted, and
justly, could explain away the unfavourable impression. 'My first
impression,' he says, 'about such people, founded on face and manner
alone, was invariably true; my mistake was in suffering them to come
nearer to me and explain themselves away.' I have found it otherwise;
though of course Dickens was right about his own experience: the matter
depends entirely on the idiosyncrasies of the observer. I have often
been deceived by face and expression: never, to the best of my belief
(and belief in this case is not mere opinion, but is based on results),
by manner of speaking. One peculiarity I have never found wanting in
habitually mendacious persons--a certain intonation which I cannot
describe, but recognise in a moment, suggestive of the weighing of each
sentence as it is being uttered, as though to consider how it would
tell. Another, is a peculiarity of manner, but it only shows itself
during speech; it is a sort of watchfulness often disguised under a
careless tone, but perfectly recognisable however disguised. Now, the
gentleman who gave me the experience I am about to relate, conveyed to
my mind, by every intonation of his voice and every peculiarity and
change of manner, the idea of truthfulness. I cannot convey to others
the impression thus conveyed to myself: nor do I expect that others
will share my own confidence: I simply state the case as I know it,
and as far as I know it. It will, however, be seen that a part of the
evidence was confirmed on the spot.
The conversation turned on the curability of consumption. My
informant, whom I will henceforth call A., said that, though he could
not assert from experience that consumption was curable, he believed
that in many cases where the tendency to consumption is inherited,
and the consumptive constitution indicated so manifestly that under
ordinary conditions the person would before long be hopelessly
consumptive, an entire change may be made in the condition of the body,
and the person become strong and healthy. He said: 'I belong myself
to a family many of whose members have died of consumption. My father
and mother both died of it, and all my brothers and sisters save one
brother; yet I do not look consumptive, do I?' and certainly he did
not. He then took from a pocket-book a portrait of his brother, showing
a young man manifestly in very bad health, looking worn, weary, and
emaciated. From the same pocket-book A. then took another portrait,
asking if I recognised it. I saw here again a worn and emaciated face
and figure. The picture was utterly unlike the hearty well-built man
before me, yet it manifestly represented no other. If I had been at all
doubtful, my doubts would have been removed by certain peculiarities
to which A. called my attention. I asked how the change in his health
had been brought about. He told me a very remarkable story of his
treatment of himself, part of which I omit because I am satisfied he
was mistaken in attributing to that portion of his self-treatment
any part of the good result which he had obtained, and that if many
consumptive patients adopted the remedy, a large proportion, if not
all, would inevitably succumb very quickly. The other portion of his
account is all that concerns us here, being all that illustrates our
present subject. He said: 'I determined to exercise every muscle of my
body; I set myself in front of a mirror and concentrated my attention
and all the power of my will on the muscle or set of muscles I proposed
to bring into action. Then I exercised those muscles in every way I
could think of, continuing the process till I had used in succession
every muscle over which the will has control. While carrying out this
system, I noticed that gradually the will acquired power over muscles
which before I had been quite unable to move. I may say, indeed, that
every set of muscles recognised by anatomists, except those belonging
to internal organs, gradually came under the control of my will.' Here
I interrupted, asking (not by any means as doubting his veracity, for
I did not): 'Can you do what Dundreary said he thought some fellow
might be able to do? can you waggle your left ear?' 'Why, certainly,'
he replied; and turning the left side of his head towards me, he moved
his left ear about; not, it is true, waggling it, but drawing it up and
down in a singular way, which was, he said, the only exercise he ever
gave it. He said, on this, that there are many other muscles over which
the will has ordinarily no control, but may be made to obtain control;
and forthwith, drawing the cloth of his trousers rather tight round
the right thigh (so that the movement he was about to show might be
discernible) he made in succession the three muscles of the front and
inner side of the thigh rise about half an inch along some nine or ten
inches of their length. Now, though these muscles are among those which
are governed by the will, for they are used in a variety of movements,
yet not one in ten thousand, perhaps in a million, can move them in the
way described.
How far A.'s system of exciting the muscles individually as well as in
groups may have operated in improving his health, as he supposed, I am
not now inquiring. What I wish specially to notice is the influence
which the will may be made to obtain over muscles ordinarily beyond
its control. It may be that under the exceptional influence of the
imagination, in the hypnotic condition, the will obtains a similar
control for a while over even those parts of the nervous system which
appertain to the so-called involuntary processes. In other words,
the case I have cited may be regarded as occupying a sort of middle
position between ordinary cases of muscular action and those perplexing
cases in which the hypnotic subject seems able to influence pulsation,
circulation, and processes of secretion in the various parts or organs
of his body.
It must be noted, however, that the phenomena of hypnotism are due
solely to the influence of the imagination. The quasi-scientific
explanations which attributed them to magnetism, electricity, some
subtle animal fluid, some occult force, and so forth, have been as
completely negatived as the supernatural explanation. We have seen that
painted wooden tractors were as effectual as the metal tractors of the
earlier mesmerists; a small disc of card or wood is as effective as
the disc of zinc and copper used by the electro-biologists; and now
it appears that the mystical influence, or what was thought such, of
the operator is no more essential to success than magnetic or electric
apparatus.
Dr. Noble of Manchester made several experiments to determine this
point. Some among them seem absolutely decisive.
Thus, a friend of Dr. Noble's had a female servant whom he had
frequently thrown into the hypnotic state, trying a variety of
experiments, many of which Dr. Noble had witnessed. Dr. Noble was at
length told that his friend had succeeded in magnetising her from
another room and without her knowledge, with some other stories even
more marvellous, circumstantially related by eye-witnesses, 'amongst
others by the medical attendant of the family, a most respectable and
intelligent friend' of Dr. Noble's own. As he remained unsatisfied, Dr.
Noble was invited to come and judge for himself, proposing whatever
test he pleased. 'Now had we visited the house,' he says, 'we should
have felt dissatisfied with any result,' knowing 'that the presence
of a visitor or the occurrence of anything unusual was sure to excite
expectation of some mesmeric process.' 'We therefore proposed,'
he proceeds, 'that the experiment should be carried on at our own
residence; and it was made under the following circumstances:--The
gentleman early one evening wrote a note as if on business,
directing it to ourselves. He thereupon summoned the female servant
(the mesmeric subject), requesting her to convey the note to its
destination, and to wait for an answer. The gentleman himself, in her
hearing, ordered a cab, stating that if anyone called he was going to
a place named, but was expected to return by a certain hour. Whilst
the female servant was dressing for her errand, the master placed
himself in the vehicle and rapidly arrived at our dwelling. In about
ten minutes after the note arrived, the gentleman in the meantime
being secreted in an adjoining apartment, we requested the young woman
who had been shown into our study, to take a seat whilst we wrote the
answer; at the same time placing the chair with its back to the door
leading into the next room which was left ajar. It had been agreed
that after the admission of the girl into the place where we were, the
magnetiser, approaching the door in silence on the other side, should
commence operations. There, then, was the patient or "subject" placed
within two feet of her magnetiser, a door only intervening, and that
but partially closed; but she, all the while, perfectly free from all
idea of what was going on. We were careful to avoid any unnecessary
conversation with the girl, or even to look towards her, lest we
should raise some suspicion in her own mind. We wrote our letter (as
if in answer) for nearly a quarter of an hour, once or twice only
making an indifferent remark, and on leaving the room for a light to
seal the supposed letter, we beckoned the operator away. No effect
whatever had been produced, although we had been told that two or three
minutes were sufficient, even when mesmerising from the drawing-room,
through walls and apartments, into the kitchen. In our own experiment
the intervening distance had been very much less, and only one solid
substance intervened, and that not completely; but here we suspect was
the difference--_the "subject" was unconscious of the magnetism and
expected nothing_.'
In another case Dr. Noble tried the converse experiment with equally
convincing results. Being in company one evening with a young lady
said to be of high mesmeric susceptibility, he requested and
received permission to test this quality in her. In one of the usual
ways he 'magnetised' her, and having so far satisfied himself, he
'demagnetised' her. He next proceeded to 'hypnotise' her, adopting Mr.
Braid's method of directing the stare at a fixed point. 'The result
varied in no respect from that which had taken place in the foregoing
experiment; the duration of the process was the same, and its intensity
of effect neither greater nor less.' 'De-hypnotisation' again restored
the young lady to herself. 'And now,' says Dr. Noble, 'we requested
our patient to rest quietly at the fire-place, to think of just what
she liked, and to look where she pleased, excepting at ourselves,
who retreated behind her chair, saying that a new mode was about to
be tried, and that her turning round would disturb the process. We
very composedly took up a volume which lay upon a table, and amused
ourselves with it for about five minutes, when on raising our eyes, we
could see by the excited features of other members of the party that
the young lady was once more _magnetised_. We were informed by those
who had attentively watched her during the progress of our little
experiment, that all had been in every respect just as before. The lady
herself, before she was undeceived, expressed a distinct consciousness
of having _felt our unseen passes streaming down the neck_.'
In a similar way, Mr. Bertrand, who was the first (Dr. Carpenter tells
us) to undertake a really scientific investigation of the phenomena
of mesmerism, proved that the supposed effect of a magnetised letter
from him to a female somnambule was entirely the work of her own lively
imagination. He magnetised a letter first, which on receipt was placed
at his suggestion upon the epigastrium of the patient, who was thrown
into the magnetic sleep with all the customary phenomena. He then wrote
another letter, which he did not magnetise, and again the same effect
was produced. Lastly he set about an experiment which should determine
the real state of the case. 'I asked one of my friends,' he says, 'to
write a few lines in my place, and to strive to imitate my writing,
so that those who should read the letter should mistake it for mine (I
knew he could do so). He did this; our stratagem succeeded, and the
sleep was produced just as it would have been by one of my own letters.
It is hardly necessary to say, perhaps, that none of the phenomena
of hypnotism require, as indeed none of them, rightly understood,
suggest, the action of any such occult forces as spiritualists believe
in. On the other hand, I believe that many of the phenomena recorded
by spiritualists as having occurred under their actual observation
are very readily to be explained as phenomena of hypnotism. Of course
I would not for a moment deny that in the great majority of cases
much grosser forms of deception are employed. But in others, and
especially in those where the concentration of the attention for some
time is a necessary preliminary to the exhibition of the phenomena
(which suitable 'subjects' only are privileged to see), I consider the
resulting self-deception as hypnotic.
We may regard the phenomena of hypnotism in two aspects--first and
chiefly as illustrating the influence of imagination on the functions
of the body; secondly, as showing under what conditions the imagination
may be most readily brought to bear in producing such influence. These
phenomena deserve far closer and at the same time far wider attention
than they have yet received. Doubt has been thrown upon them because
they have been associated with false theories, and in many cases with
fraud and delusion. But, rightly viewed, they are at once instructive
and valuable. On the one hand they throw light on some of the most
interesting problems of mental physiology; on the other they promise to
afford valuable means of curing certain ailments, and of influencing
in useful ways certain powers and functions of the body. All that is
necessary, it should seem, to give hypnotic researches their full
value, is that all association of these purely mental phenomena with
charlatanry and fraud should be abruptly and definitely broken off.
Those who make practical application of the phenomena of hypnotism
should not only divest their own minds of all idea that some occult
and as it were extra-natural force is at work, but should encourage no
belief in such force in those on whom the hypnotic method is employed.
Their influence on the patient will not be lessened, I believe, by the
fullest knowledge on the patient's part that all which is to happen to
him is purely natural--that, in fact, advantage is simply to be taken
of an observed property of the imagination to obtain an influence not
otherwise attainable over the body as a whole (as when the so-called
magnetic sleep is to be produced), or over special parts of the body.
Whether advantage might not be taken of other than the curative
influences of hypnotism is a question which will probably have occurred
to some who may have followed the curious accounts given in the
preceding pages. If special powers may be obtained, even for a short
time, by the hypnotised subject, these powers might be systematically
used for other purposes than mere experiment. If, again, the repetition
of hypnotic curative processes eventually leads to a complete and
lasting change in the condition of certain parts or organs of the body,
the repetition of the exercise of special powers during the hypnotic
state may after a while lead to the definite acquisition of such
powers. As it now appears that the hypnotic control may be obtained
without any effort on the part of the operator, the effort formerly
supposed to be required being purely imaginary and the hypnotic state
being in fact readily attainable without any operation whatever, we
seem to recognise possibilities which, duly developed, might be found
of extreme value to the human race. In fine, it would seem that man
possesses a power which has hitherto lain almost entirely dormant, by
which, under the influence of properly-guided imagination, the will
can be so concentrated on special actions that feats of strength,
dexterity, artistic (and even perhaps scientific) skill may be
accomplished by persons who, in the ordinary state, are quite incapable
of such achievements.
_HEREDITARY TRAITS._
In Montaigne's well-known essay on the 'Resemblance of Children to
their Fathers,' the philosopher of Périgord remarks that 'there is
a certain sort of crafty humility that springs from presumption; as
this, for example, that we confess our ignorance in many things, and
are so courteous as to acknowledge that there are in works of nature
some qualities and conditions that are imperceptible to us, and of
which our understanding cannot discern the means and causes; by which
honest declaration we hope to obtain that people shall also believe
us of those that we say we do understand.' 'We need not trouble
ourselves,' he goes on, 'to seek out miracles and strange difficulties;
methinks there are such incomprehensible wonders amongst the things
that we ordinarily see as surpass all difficulties of miracles.' He
applies these remarks to inherited peculiarities of feature, figure,
character, constitution, habits, and so forth. And certainly few of
the phenomena of nature are more wonderful than these, in the sense of
being less obviously referable to any cause which seems competent to
produce them. Many of those natural phenomena which are regarded as
most striking are in this respect not to be compared with the known
phenomena of heredity. The motions of the planets can all be referred
to regular laws; chemical changes are systematic, and their sequence at
least is understood; the phenomena of heat, light, and electricity are
gradually finding interpretation. It is true that all these phenomena
become in a sense as miracles when we endeavour to ascertain their
real cause. In their case we can ascertain the 'how,' but in no sense
the 'why.' Gravity is a mastery of mysteries to the astronomer, and
has almost compelled us to believe in that 'action at a distance'
which Newton asserted to be unimaginable by anyone with a competent
power of reasoning about things philosophical. The ultimate cause of
chemical changes is as great a mystery now as it was when the four
elements were believed in. And the nature of the ether itself in which
the undulations of heat, light, and electricity are transmitted is
utterly mysterious even to those students of science who have been most
successful in determining the laws according to which those undulations
proceed. But the phenomena themselves being at once referable (in
our own time at least) to law, have no longer the mysterious and in
a sense miraculous character recognised in them before the laws of
motion, of chemical affinity, of light and heat and electricity, had
been ascertained. It is quite otherwise with the phenomena of heredity.
We know nothing even of the proximate cause of any single phenomenon;
far less of that ultimate cause in which all these phenomena had their
origin. The inheritance of a trait of bodily figure, character, or
manner is a mystery as great as that other and cognate mystery, the
appearance of some seemingly sudden variation in a race which has
for many generations presented an apparently unvarying succession of
attributes, bodily, physical, or mental.
It need hardly be said that this would not be the place for the
discussion of the problems of heredity and variation, even if in the
present position of science we could hope for any profitable result
from the investigation of either subject. But some of the curious facts
which have been noted by various students of heredity will, I think,
be found interesting; and though not suggesting in the remotest degree
any solution of the real difficulties of the subject, they may afford
some indication of the laws according to which parental traits are
inherited, or seemingly sudden variations introduced.
The commonest, and therefore the least interesting, though perhaps the
most instructive of the phenomena of heredity, are those affecting
the features and the outward configuration of the body. These have
been recognised in all ages and among all nations. A portion of the
Jewish system of legislature was based on a recognition of the law that
children inherit the bodily qualities of the parents. The Greeks noted
the same fact. Among the Spartans, indeed, a system of selection from
among new-born children prevailed, which, though probably intended
only to eliminate the weaker individuals, corresponded closely to
what would be done by a nation having full belief in the efficacy
of both natural and artificial selection, and not troubled with any
strong scruples as to the method of applying their doctrines on such
matters. Among the Romans we find certain families described by their
physical characteristics, as the _Nasones_ or Big-nosed, the _Labeones_
or Thick-lipped, the _Capitones_ or Big-headed, the _Buccones_ or
Swollen-cheeked. In more recent times similar traits have been
recognised in various families. The Austrian lip and the Bourbon nose
are well-known instances.[15]
Peculiarities of structure have a double interest, as illustrating both
variation and persistence. We usually find them introduced without any
apparent cause into a family, and afterwards they remain as hereditary
traits, first inherited regularly, then intermittently, and eventually,
in most cases, dying out or becoming so exceptional that their
occurrence is not regarded as an hereditary peculiarity. Montaigne
mentions that in the family of Lepidus, at Rome, there were three, not
successively but by intervals, that were born with the same eye covered
with a cartilage. At Thebes there was a family almost every member of
which had the crown of the head pointed like a lance-head; all whose
heads were not so formed being regarded as illegitimate. A better
authenticated case is that of the Lambert family. The peculiarity
affecting this family appeared first in the person of Edward Lambert,
whose whole body, except the face, the palms of the hands, and the
soles of the feet, was covered with a sort of shell consisting of
horny excrescences. He was the father of six children, all of whom,
so soon as they had reached the age of six weeks, presented the same
peculiarity. Only one of them lived. He married, and transmitted the
peculiarity to all his sons. For five generations all the male members
of the Lambert family were distinguished by the horny excrescences
which had adorned the body of Edward Lambert.
A remarkable instance of the transmission of anomalous characteristics
is found in the case of Andrian Jeftichjew, who, three or four years
ago, was exhibited with his son Fedor Jeftichjew in Berlin and Paris.
They were called in Paris _les hommes-chiens_, or dog-men, the father's
face being so covered with hair as to present a striking resemblance to
the face of a Skye terrier. Andrian was thus described:--'He is about
fifty-five years of age, and is said to have been the son of a Russian
soldier. In order to escape the derision and the unkind usage of his
fellow-villagers, Andrian in early life fled to the woods, where for
some time he lived in a cave.
During this period of seclusion he was much given to drunkenness. His
mental condition does not seem to have suffered, however, and he is
on the whole of a kindly and affectionate disposition. It may be of
interest to state that he is an orthodox member of the Russo-Greek
Church, and that, degraded as he is intellectually, he has very
definite notions about heaven and the hereafter. He hopes to introduce
his frightful countenance into the court of heaven, and he devotes all
the money he makes, over and above his outlay for creature comforts,
to purchasing the prayers of a devout community of monks in his native
village, Kostroma, after his mortal career is ended. He is of medium
stature, but very strongly built. His excessive capillary development
is not true hair, but simply an abnormal growth of the _down_ or fine
hairs which usually cover nearly the entire surface of the human
body. Strictly speaking, he has neither head-hair, beard, moustache,
eyebrows, nor eyelashes, their place being taken by this singular
growth of long silky down. In colour this is of a dirty yellow; it is
about three inches in length all over the face, and feels like the hair
of a Newfoundland dog. The very eyelids are covered with this long
hair, while flowing locks come out of his nostrils and ears. On his
body are isolated patches, strewed but not thickly with hairs one and
a half to two inches long.' Dr. Bertillon, of Paris, compared a hair
from Andrian's chin with a very fine hair from a man's beard, and found
that the latter was three times as thick as the former; and a hair from
Andrian's head is only one-half as thick as an average human hair.
Professor Virchow, of Berlin, made careful inquiry into the family
history of Andrian Jeftichjew. So far as could be learned, Andrian was
the first in whom this wonderful hirsuteness had been noticed. Neither
his reputed father nor his mother presented any peculiarity of the
kind, and a brother and sister of his, who are still living, are in
no way remarkable for capillary development. The son Fedor, who was
exhibited in company with Andrian, was illegitimate, and about three
years of age. Andrian's legitimate children, a son and a daughter, both
died young. Nothing is known of the former; but the daughter resembled
the father. 'Fedor is a sprightly child,' said the account from which
we have already quoted, 'and appears more intelligent than the father.'
The growth of down on his face is not so heavy as to conceal his
features, but there is no doubt that when the child comes to maturity
he will be at least as hirsute as his parent The hairs are as white
and as soft as the fur of the Angora cat, and are longest at the outer
angles of the eyes. There is a thick tuft between the eyes, and the
nose is well covered. The moustache joins the whiskers on each side,
after the English fashion, and this circumstance gives to accurate
pictures of the child a ludicrous resemblance to a well-fed Englishman
of about fifty. As in the father's case, the inside of Fedor's nostrils
and ears has a thick crop of hair.' 'Both father and son are almost
toothless, Andrian having only five teeth, one in the upper jaw and
four in the lower, while the child has only four teeth, all in the
lower jaw. In both cases the four lower teeth are all incisors. To
the right of Andrian's one upper tooth there still remains the mark
of another which has disappeared. That beyond these six teeth the man
never had any others is evident to anyone who feels the gums with the
finger.'
The deficiency of teeth, accompanied as it is by what is in reality a
deficiency not a redundancy of hair--for Andrian and his son have no
real hair--accords well with Darwin's view, that a constant correlation
exists between hair and teeth. He mentions as an illustration the
deficiency of teeth in hairless dogs. The tusks of the boar, again, are
greatly reduced under domestication, and the reduction is accompanied
by a corresponding diminution of the bristles. He mentions also the
case of Julia Pastrana, a Spanish dancer or opera singer, who had a
thick masculine beard and a hairy forehead, while her teeth were so
redundant that her mouth projected, and her face had a gorilla-like
appearance. It should rather be said that in general those creatures
which present an abnormal development in the covering of their skin,
whether in the way of redundancy or deficiency, present, generally,
perhaps always, an abnormal dental development, as we see in sloths and
armadilloes on the one hand, which have the front teeth deficient, and
in some branches of the whale family on the other, in which the teeth
are redundant either in number or in size. In individual members of the
human family it certainly is not always the case that the development
of the hair and that of the teeth are directly correlated; for some
who are bald when quite young have excellent teeth, and some who have
lost most of their teeth while still on the right side of forty have
excellent hair to an advanced age.[16]
Another case, somewhat similar to that of Andrian and his son, is found
in a Burmese family, living at Ava, and first described by Crawford in
1829. Shwe-Maong, the head of the family, was about thirty years old.
His whole body was covered with silky hairs, which attained a length of
nearly five inches on the shoulders and spine. He had four daughters,
but only one of them resembled him. She was living at Ava in 1855, and,
according to the account given by a British officer who saw her there,
she had a son who was hairy like his grandfather, Shwe-Maong. The case
of this family illustrates rather curiously the relation between the
hair and teeth. For Shwe-Maong retained his milk-teeth till he was
twenty years old (when he attained puberty), and they were replaced by
nine teeth only, five in the upper and four in the lower jaw. Eight of
these were incisors, the ninth (in the upper jaw) being a canine tooth.
Sex-digitism, or the possession of hands and feet with six digits
each, has occurred in several families as a sudden variation from
the normal formation, but after it has appeared has usually been
transmitted for several generations. In the case of the Colburn family
this peculiarity lasted for four generations without interruption, and
still reappears occasionally. In a branch of a well-known Scotch family
sex-digitism--after continuing for three or four generations--has
apparently disappeared; but it still frequently happens that the edge
of the hands on the side of the little finger is partially deformed.
Hare-lip, albinism, halting, and other peculiarities, commonly reappear
for four or five generations, and are seldom altogether eradicated in
less than ten or twelve.
The tendency to variation shown in the introduction of these
peculiarities, even though they may have been eventually eradicated, is
worth noticing in its bearing on our views respecting the formation of
new and persistent varieties of the human as of other races. It must be
noticed that in the case of the human race the conditions not only do
not favour the continuance of such varieties, but practically forbid
their persistence. It is otherwise with some varieties, at least, of
domestic animals, insomuch that varieties which present any noteworthy
even though accidentally observed advantage have been made practically
persistent; we say practically, because there seems little reason to
doubt that in every case which has hitherto been observed the normal
type would eventually be reverted to if special pains were not taken to
separate the normal from the abnormal form.
An excellent illustration of the difference between the human race and
a race of animals under domestication, in this particular respect, is
found in the case of the Kelleia family on the one hand, and that of
the Ancon or Otter sheep on the other.
The former case is described by Réaumur. A Maltese couple named
Kelleia, whose hands and feet were of the ordinary type, had a son
Gratio who had six movable fingers on each hand and six somewhat less
perfect toes on each foot. Gratio Kelleia married a woman possessing
only the ordinary number of fingers and toes. There were four children
of this marriage--Salvator, George, André, and Marie. Salvator had six
fingers and six toes like the father; George and André had each five
fingers and five toes like the mother, but the hands and feet of George
were slightly deformed; Marie had five fingers and five toes, but her
thumbs were slightly deformed. All four children grew up, and married
folk with the ordinary number of fingers and toes. The children of
André alone (who were many) were without exception of the normal type,
like their father. The children of Salvator, who alone was six-fingered
and six-toed like Gratio the grandfather, were four in number; three
of them resembled the father, while the other--the youngest--was
of the normal type like his mother and grandmother. As these four
children were the descendants of four grandparents of whom one only was
hexadactylic, we see that the variety had been strong enough in their
case to overcome the normal type in threefold greater strength. But
the strangest part of the story is that relating to George and Marie.
George, who was a pentadactyle, though somewhat deformed about the
hands and feet, was the father of four children: first, two girls, both
purely hexadactylic; next, a girl hexadactylic on the right side of
the body and pentadactylic on the left side; and lastly, a boy, purely
pentadactylic. Marie, a pentadactyle with deformed thumbs, gave birth
to a boy with six toes, and three normally formed children. It will be
seen, however, that the normal type showed itself in greater force than
the variety in the third generation from Gratio: for while one child
of Salvator's, one of George's, three of Marie's, and all of André's
(some seven or eight) were of the normal type--twelve or thirteen
in all--only five, viz., three of Salvator's and two of George's,
presented the variety purely. Three others were more or less abnormally
formed in fingers and toes; but even counting these, the influence of
the variety was shown only in eight of the grandchildren of Gratio,
whereas twelve or thirteen were of the normal type.
The story of the Ancon or Otter sheep, as narrated by Colonel
David Humphreys in a letter to Sir Joseph Banks, published in the
_Philosophical Transactions_ for 1813, has been thus abridged by
Huxley:--'It appears that one Seth Wright, the proprietor of a farm on
the banks of the Charles River, in Massachusetts, possessed a flock
of fifteen ewes and a ram of the ordinary kind. In the year 1791 one
of the ewes presented her owner with a male lamb differing, for no
assignable reason, from its parents by a disproportionately long body
and short bandy legs; whence it was unable to emulate its relatives in
those sportive leaps over the neighbours' fences in which they were
in the habit of indulging, much to the good farmer's vexation. With
the "cuteness" characteristic of their nation, the neighbours of the
Massachusetts farmer imagined it would be an excellent thing if all
his sheep were imbued with the stay-at-home tendencies enforced by
Nature upon the newly-arrived ram; and they advised Wright to kill
the old patriarch of his fold and instal the new Ancon ram in his
place. The result justified their sagacious anticipations.... The
young lambs were almost always either pure Ancons or pure ordinary
sheep. But when sufficient Ancon sheep were obtained to interbreed
with one another, it was found that the offspring were always pure
Ancon. Colonel Humphreys, in fact, states that he was acquainted with
only "one questionable case of a contrary nature." By taking care to
select Ancons of both sexes for breeding from, it thus became easy to
establish an exceedingly well-marked race--so peculiar that even when
herded with other sheep, it was noted that the Ancons kept together.
And there is every reason to believe that the existence of this breed
might have been indefinitely protracted: but the introduction of the
Merino sheep--which were not only very superior to the Ancons in wool
and meat, but quite as quiet and orderly--led to the complete neglect
of the new breed, so that in 1813 Colonel Humphreys found it difficult
to obtain the specimen whose skeleton was presented to Sir Joseph
Banks. We believe that for many years no remnant of it has existed in
the United States.'
It is easy, as Huxley remarks, to understand why, whereas Gratio
Kelleia did not become the ancestor of a race of six-figured and
six-toed men, Seth Wright's Ancon ram became a nation of long-bodied,
short-legged sheep. If the purely hexadactylic descendants of Gratio
Kelleia, and all the purely hexadactylic members of the Colburn family,
in the third and fourth generations, had migrated to some desert
island, and had been careful not only to exclude all visitors having
the normal number of fingers and toes, but to send away before the
age of puberty all children of their own which might depart in any
degree from the pure hexadactylic type, there can be no doubt that
under favourable conditions the colony would have become a nation
of six-fingered folk. Among such a nation the duodecimal system
of notation would flourish, and some remarkable performers on the
pianoforte, flute, and other instruments, might be looked for; but we
do not know that they would possess any other advantage over their
pentadactylic contemporaries. Seeing that the system of colonising
above described is antecedently unlikely, and that no special advantage
could be derived from the persistence of any hitherto known abnormal
variety of the human race, it is unlikely that for many generations
yet to come we shall hear of six-fingered, hairy-faced, horny-skinned,
or hare-lipped nations. The only peculiarities which have any chance
of becoming permanent are such as, while not very uncommon, stand
in the way of intermarriage with persons not similarly affected.
A similar remark, as will presently appear, applies to mental and
moral characteristics. The law according to which contrast is found
attractive and similitude repugnant, though wide in its range, is not
universal; and there are cases in which resemblance, if it has not
the charm found (under ordinary circumstances) in contrast, is yet a
necessary element in matrimonial alliances.
The inheritance of constitutional traits comes next to be considered.
It is probably not less frequently observed, and is in several respects
more interesting than the inheritance of peculiarities of bodily
configuration.
Longevity, which may be regarded as measuring the aggregate
constitutional energy, is well known to be hereditary in certain
families, as is short duration of life in other families. The best
proof that this is the case is found in the action of insurance
companies, in ascertaining through their agents the longevity of the
ancestors of persons proposing to insure their lives. Instances of
longevity during several successive generations are too common to
be worth citing. Cases in which, for generation after generation, a
certain age, far short of the threescore years and ten, has not been
passed, even when all the circumstances have favoured longevity, are
more interesting. One of the most curious among these is the case of
the Turgot family, in which the age of fifty-nine had not been for
generations exceeded, to the time when Turgot made the name famous.
At the age of fifty, when he was in excellent health, and apparently
had promise of many years of life, he expressed to his friends his
conviction that the end of his life was near at hand. From that time
forward he held himself prepared for death, and, as we know, he died
before he had completed his fifty-fourth year.
Fecundity is associated sometimes with longevity, but in other cases it
is as significantly associated with short duration of life. Of families
in which many children are born but few survive, we naturally have
less striking evidence than we have of families in which many children
of strong constitutions are born for several successive generations.
What may be called the fecundity of the short-lived is a quality
commonly leading in no long time to the disappearance of the family
in which it makes its appearance. It is the reverse, of course, with
fecundity in families whose members show individually great vigour of
constitution and high vital power. Ribot mentions several cases of this
sort among the families of the old French _noblesse_. Thus Anne de
Montmorency--who, despite his feminine name, was certainly by no means
feminine in character (at the Battle of St. Denis, in his sixty-sixth
year, he smashed with his sword the teeth of the Scotch soldier who was
giving him his death-blow) was the father of twelve children. Three of
his ancestors, Matthew I., Matthew II., and Matthew III., had, in all,
eighteen children, of whom fifteen were boys. 'The son and grandson of
the great Condé had nineteen between them, and their great-grandfather,
who lost his life at Jarnac, had ten. The first four Guises reckoned
in all forty-three children, of whom thirty were boys. Achille de
Harley had nine children, his father ten, and his great-grandfather
eighteen.' In the family of the Herschels in Hanover and in England, a
similar fecundity has been shown in two generations out of three. Sir
W. Herschel was one of a family of twelve children, of whom five were
sons. He himself did not marry till his fiftieth year, and had only one
son. But Sir John Herschel was the father of eleven children.
Of constitutional peculiarities those affecting the nervous system
are most frequently transmitted. We do not, however, consider them
at this point, because they are viewed ordinarily rather as they
relate to mental and moral characteristics than as affections of
the body. The bodily affections most commonly transmitted are those
depending on what is called diathesis--a general state or disposition
of the constitution predisposing to some special disease. Such are
scrofula, cancer, tubercular consumption, gout, arthritis, and some
diseases specially affecting the skin. It would not be desirable to
discuss here this particular part of our subject, interesting though
it undoubtedly is. But it may be worth while to note that we have,
in the variety of forms in which the same constitutional bad quality
may present itself, evidence that what is actually transmitted is not
a peculiarity affecting a particular organ, even though in several
successive generations the disease may show itself in the same part of
the body, but an affection of the constitution generally. We have here
an answer to the question asked by Montaigne in the essay from which
we have already quoted. The essay was written soon after he had for
the first time experienced the pangs of renal calculus:--''Tis to be
believed,' he says, 'that I derived this infirmity from my father, for
he died wonderfully tormented' with it; he was 'never sensible of his
disease till the sixty-seventh year of his age, and before that had
never felt any grudging or symptom of it' ... 'but lived till then in
a happy vigorous state of health, little subject to infirmities, and
continued seven years after in this disease, and dyed a very painful
death. I was born about twenty-five years before his disease seized
him, and in the time of his most flourishing and healthful state of
body, his third child in order of birth: where could his propension
to this malady lie lurking all that while? And he being so far from
the infirmity, how could that small part of his substance carry away
so great an impression of its share? And how so concealed that, till
five-and-forty years after, I did not begin to be sensible of it? being
the only one to this hour, amongst so many brothers and sisters, and
all of one mother, that was ever troubled with it. He that can satisfie
me in this point, I will believe him in as many other miracles as he
pleases, always provided that, as their manner is, he does not give me
a doctrine much more intricate and fantastic than the thing itself, for
current pay.' When we note, however, that in many cases the children
of persons affected like the elder Montaigne are not affected like
the parents, but with other infirmities, as the tendency to gout,
and _vice versâ_ (a circumstance of which I myself have but too good
reason to be cognisant, a parent's tendency to gout having in my case
been transmitted in the modified but even more troublesome form of
the disease which occasioned Montaigne so much anguish), we perceive
that it is not 'some small part of the substance' which transmits its
condition to the child, but the general state of the constitution.
Moreover, it may be hoped in many cases (which would scarcely be the
case if the condition or qualities of some part of the body only were
transmitted) that the germs of disease, or rather the predisposition
to disease, may be greatly diminished, or even entirely eradicated, by
suitable precautions. Thus persons inheriting a tendency to consumption
have become, in many cases, vigorous and healthy by passing as much
of their time as possible in the open air, by avoiding crowded and
over-heated rooms, taking moderate but regular exercise, judicious
diet, and so forth. We believe that the disease which troubled the
last fifteen years of the life of Montaigne might readily have been
prevented, and the tendency to it eradicated, during his youth.
Let us turn, however, from these considerations to others more
interesting, though less important, and on the whole perhaps better
suited to these pages.
The inheritance of tricks or habits is one of the most perplexing
of all the phenomena of heredity. The less striking the habit, the
more remarkable, perhaps, is its persistence as an inherited trait.
Giron de Buzareingues states that he knew a man who, when he lay on
his back, was wont to throw his right leg across the left; one of
this person's daughters had the same habit from her birth, constantly
assuming that position in the cradle, notwithstanding the resistance
offered by the swaddling bands.[17] Darwin mentions another case in
his _Variation of Animals and Plants under Domestication_:--A child
had the odd habit of setting its fingers in rapid motion whenever it
was particularly pleased with anything. When greatly excited, the same
child would raise the hand on both sides as high as the eyes, with the
fingers in rapid motion as before. Even in old age he experienced a
difficulty in refraining from these gestures. He had eight children,
one of whom, a little girl, when four years of age, used to set her
fingers going, and to lift up her hands after the manner of her father.
A still more remarkable case is described by Galton. A gentleman's wife
noticed that when he lay fast asleep on his back in bed he had the
curious trick of raising his right arm slowly in front of his face,
up to his forehead, and then dropping it with a jerk, so that the
wrist fell heavily on the bridge of his nose. The trick did not occur
every night, but occasionally, and was independent of any ascertained
cause. Sometimes it was repeated incessantly for an hour or more. The
gentleman's nose was prominent, and its bridge often became sore from
blows which it received. At one time an awkward sore was produced
that was long in healing, on account of the recurrence, night after
night, of the blows which first caused it. His wife had to remove the
button from the wrist of his night-gown, as it made severe scratches,
and some means were attempted of tying his arm. Many years after
his death, his son married a lady who had never heard of the family
incident. She, however, observed precisely the same peculiarity in her
husband; but his nose, from not being particularly prominent, has never
as yet suffered from the blows. The trick does not occur when he is
half asleep, as, for example, when he is dozing in his arm-chair; but
the moment he is fast asleep, he is apt to begin. It is, as with his
father, intermittent; sometimes ceasing for many nights, and sometimes
almost incessant during a part of every night. It is performed, as it
was with his father, with his right hand. One of his children, a girl,
has inherited the same trick. She performs it, likewise, with the right
hand, but in a slightly modified form; for after raising the arm, she
does not allow the wrist to drop upon the bridge of the nose, but the
palm of her half-closed hand falls over and down the nose, striking it
rather rapidly--a decided improvement on the father's and grandfather's
method. The trick is intermittent in this girl's case also, sometimes
not occurring for periods of several months but sometimes almost
incessantly.
Strength in particular limbs or muscles is often transmitted
hereditarily. So also is skill in special exercises. Thus in the north
country there are families of famous wrestlers. Among professional
oarsmen, again, we may note such cases as the Clasper family in the
north, the Mackinneys in the south; while among amateur oarsmen we have
the case of the Playford family, to which the present amateur champion
sculler belongs. In cricket, the Walker family and the Grace family
may be cited among amateurs, the Humphreys among professional players.
Grace in dancing was transmitted for three generations in the Vestris
family. It must, however, be noted that in some of these cases we may
fairly consider that example and teaching have had much to do with the
result. Take rowing for instance. A good oarsman will impart his style
to a whole crew if he rows stroke for them; and even if he only trains
them (as Morrison, for instance, trained the Cambridge crew a few years
ago), he will make good oarsmen of men suitably framed and possessing
ordinary aptitude for rowing. I remember well how a famous stroke-oar
at Cambridge (John Hall, of Magdalen,) imparted to one at least of the
University crew (a fellow-collegian of his, and therefore rowing with
him constantly also in his College boat) so exact an imitation of his
style that one rather dusky evening, when the latter was 'stroking' a
scratch four past a throng of University men, a dispute arose as to
which of the two was really stroke of the four. Anyone who knows how
characteristic commonly is the rowing of any first-class stroke, and
still more anyone who chances to know how peculiar was the style of the
University 'stroke-oar' referred to, will understand how closely his
style must have been adopted, when experienced oarsmen, not many yards
from the passing four, were unable to decide at once which of the two
men were rowing,--even though the evening was dusky enough to prevent
the features of the stroke (whose face was not fully in view at the
moment) from being discerned. Seeing that a first-rate oarsman can thus
communicate his style so perfectly to another, it cannot be regarded as
demonstrably a case of hereditary transmission if the Claspers rowed
in the same style as their father, or if the present champion amateur
sculler (making allowances for the change introduced by the sliding
seat) rows very much like his father and his uncle.
Some peculiarities, such as stammering, lisping, babbling, and the
like, are not easily referable to any special class of hereditary
traits, because it is not clear how far they are to be regarded as
depending on bodily or how far on mental peculiarities. It might seem
obvious that stammering was in most cases uncontrollable by the will,
and babbling might seem as certainly controllable. Yet there are cases
which throw doubt on either conclusion. Thus, Dr. Lucas tells us of
a servant-maid whose loquacity was apparently quite uncontrollable.
She would talk to people till they were ready to faint; and if there
were no human being to listen to her, she would talk to animals and
inanimate objects, or would talk aloud to herself. She had to be
discharged. 'But,' she said to her master, 'I am not to blame; it all
comes from my father. He had the same fault, and it drove my mother
to distraction; and his father was just the same.' Stammering has
been transmitted through as many as five generations. The same has
been noticed of peculiarities of vision. The Montmorency look, a sort
of half squint, affected nearly all the members of the Montmorency
family. The peculiarity called Daltonism, an inability to distinguish
between certain colours of the spectrum, was not so named, as is often
asserted, merely because the distinguished chemist Dalton was affected
by it, but because three members of the same family were similarly
affected. Deafness and blindness are not commonly hereditary where
the parents have lost sight or hearing either by accident or through
illness, even though the illness or accident occur during infancy; but
persons born either blind or deaf frequently if not commonly transmit
the defect to some at least among their offspring. Similar remarks
apply to deaf-mutism.
The senses of taste and smell must also be included in the list of
those which are affected by transmitted peculiarities. If we include
the craving for liquor among such peculiarities, we might at once
cite a long list of cases; but this craving must be regarded as
nervo-psychical, the sense of taste having in reality very little to
do with it. It is doubtful how the following hideous instance should
be classed. It is related by Dr. Lucas. 'A man in Scotland had an
irresistible desire to eat human flesh. He had a daughter; although
removed from her father and mother, who were both sent to the stake
before she was a year old, and although brought up among respectable
people, this girl, like her father, yielded to the horrible craving for
human flesh.' He must be an ardent student of physiological science who
regrets that at this stage circumstances intervened which prevented the
world from ascertaining whether the peculiarity would have descended to
the third and fourth generations.
Amongst the strangest cases of hereditary transmissions are those
relating to handwriting. Darwin cites several curious instances in
his _Variation of Plants and Animals under Domestication_. 'On what
a curious combination of corporeal structure, mental character, and
training,' he remarks, 'must handwriting depend. Yet everyone must have
noted the occasional close similarity of the handwriting in father and
son, even although the father had not taught the son. A great collector
of franks assured me that in his collection there were several franks
of father and son hardly distinguishable except by their dates.'
Hofacker, in Germany, remarks on the inheritance of handwriting, and it
has been even asserted that English boys when taught to write in France
naturally cling to their English manner of writing. Dr. Carpenter
mentions the following instance as having occurred in his own family,
as showing that the character of the handwriting is independent of
the special teaching which the right hand receives in this art:--'A
gentleman who emigrated to the United States and settled in the back
woods, before the end of last century, was accustomed from time to time
to write long letters to his sister in England, giving an account
of his family affairs. Having lost his right arm by an accident, the
correspondence was temporarily kept up by one or other of his children;
but in the course of a few months he learned to write with his left
hand, and before long, the handwriting of the letters thus written came
to be indistinguishable from that of his former letters.'
I had occasion two or three years ago to consider in an article on
'Strange Mental Feats,' in my _Science Byeways_, the question of
inherited mental qualities and artistic habits, and would refer the
reader for some remarkable instances of transmitted powers to that
article.[18] Galton in his work on _Hereditary Genius_, and Ribot in
his treatise on _Heredity_, have collected many facts bearing on this
interesting question. Both writers show a decided bias in favour of
a view which would give to heredity a rather too important position
among the factors of genius. Cases are cited which seem very little
to the purpose, and multitudes of instances are omitted which oppose
themselves, at a first view at any rate, to the belief that heredity
plays the first part in the genesis of great minds. Nearly all the
greatest names in philosophy, literature, and science, and a great
number of the greatest names in art, stand absolutely alone. We know
nothing achieved by the father or grandfather of Shakspeare, or of
Goethe, or Schiller, or Evans (George Eliot), or Thackeray, or Dickens,
or Huxley. None of Newton's family were in any way distinguished in
mathematical or scientific work; nor do we know of a distinguished
Laplace, or Lagrange, or Lavoisier, or Harvey, or Dalton, or Volta,
or Faraday, besides those who made these names illustrious. As to
general literature, page after page might be filled with the mere
names of those whose ancestry has been quite undistinguished. To say
that among the ancestors of Goethe, Schiller, Byron, and so forth,
certain qualities, virtues or vices, passions or insensibilities to
passion, may be recognised 'among the ancestors of men of science,
certain aptitudes for special subjects or methods of research,' among
the ancestors of philosophers and literary men certain qualities or
capabilities, and that such ancestral peculiarities determined the
poetic, scientific, or literary genius of the descendant, is in reality
to little purpose, for there is probably not a single family possessing
claims to culture in any civilised country among the members of which
individuals might not be found with qualities thus emphasised so to
speak. Such _à posteriori_ reasoning is valueless. If instances could
be so classified that after carefully studying them we could make
even the roughest approach to a guess respecting the cases in which a
family might be expected to produce men of any particular qualities,
there would be some use in these attempts at generalisation; at present
all that can be said is that some mental qualities and some artistic
aptitudes have unquestionably in certain instances been transmitted,
and that on the whole men of great distinction in philosophy,
literature, science, and art, are rather more likely than others to
have among their relations (more or less remote) persons somewhat above
the average in mental or artistic qualities. But it is not altogether
certain that this superiority is even quite so great as it might be
expected to be if hereditary transmission played no part at all in
the matter. For it cannot be denied that a great mathematician's son
has rather a better chance than others of being a mathematician, a
great author's son of being a writer, a great artist's son of being
skilful in art, a great philosopher's son of taking philosophic views
of things. Nearly every son looks forward while still young to the
time when he shall be doing his father's work; nearly every father
hopes while his children are yet young that some at least among them
will follow his pursuits. The fact that so few sons of great men do
follow in their fathers' footsteps shows that, despite the strong
ambition of the son and the anxious hope of the father, the son in the
majority of instances has not had ability even to take a fairly good
position in the work wherein the father has been perhaps pre-eminently
distinguished.
I have said that certain mental qualities have certainly been
transmitted in some cases. Galton mentions one noteworthy instance
relating to memory. In the family of Porson good memory was so notable
a faculty as to give rise to the byword, 'the Porson memory.' Lady
Hester Stanhope, says the late F. Papillon, 'she whose life was so
full of adventure, gives, as one among many points of resemblance
between herself and her grandfather, her retentive memory. "I have my
grandfather's grey eyes," said she, "and his memory of places. If he
saw a stone on the road, he remembered it; it is the same with myself.
His eye, which was ordinarily dull and lustreless, was lighted up, like
my own, with a dull gleam whenever he was seized with passion."'
In endeavouring to form an opinion on the law of heredity in its
relation to genius, we must remember that a remark somewhat similar to
one made by Huxley respecting the origin of new species applies to the
origin of a man of genius. Before such a man became celebrated no one
cared particularly to inquire about his ancestry or relations; when
his fame was established, the time for making the inquiry had passed
away. It is quite possible that, if we had exact and full information,
in a great number of cases we might find the position taken up by Mr
Galton and M. Ribot greatly strengthened; it is, however, also possible
that we might find it much weakened, not only by the recognition of a
multitude of cases in which the approach of a great man was in no sort
indicated by scintillations of brightness along the genealogical track,
but by a yet greater number of cases in which families containing
numbers of clever, witty, and learned folks have produced none who
attained real distinction.
There is an excellent remark in a thoughtful but anonymous paper on
Heredity in the _Quarterly Journal of Science_, two years or so ago,
which suggests some considerations well worth noting. 'If we look,'
says the writer, 'on the intellect as not a single force but a complex
of faculties, we shall find little to perplex us in the phenomenon of
spontaneity'--that is (in this case), in the appearance of a man of
genius in a family not before remarkable in any way. 'Suppose a family
who have possessed some of the attributes of greatness, but who, in
virtue of a principle equally true in psychology and in mechanics,
that "nothing is stronger than its weakest part," has remained in
obscurity. Let a man of this family marry a woman whose faculties are
the complement of his own. It is possible that a child of such a couple
may combine the defects or weaknesses of both parents, and we have
then the case of spontaneous imbecility or criminality. But it is also
possible that he may combine the excellences of both, and burst upon
the world as a spontaneous genius.... Again, we must remember that,
even if we consider the intellect as "one and indivisible," it is far
from being the only faculty needful for the attainment of excellence,
even in the fields of pure science. Combined with it there must be the
moral faculties of patience, perseverance, and concentration. The will
must be strong enough to overcome all distracting temptations, whether
in themselves good or evil. Lastly, there must be constitutional energy
and endurance. Failing these, the man will merely leave among his
friends the conviction that he might have achieved greatness, if----.
We once knew a physician, resident in a small country town, who from
time to time startled his associates by some profound and suggestive
idea, some brilliant _aperçu_. But a constitutional languor prevented
him from ever completing an investigation, or from leaving the world
one written line.'
The effect of circumstances also must not be overlooked. It is certain
that some of those who stand highest in the world's repute would have
done nothing to make their names remembered but for circumstances
which either aided their efforts or compelled them to exertion; and
it cannot be doubted, therefore, that many who have been by no means
celebrated have required but favouring opportunities or the spur of
adverse circumstances to have achieved distinction. We note the cases
in which men who have been intended by their parents for the desk or
routine work have fortunately been freed for nobler work, to which
their powers have specially fitted them. But we are apt to forget that
for each such case there must be many instances in which no fortunate
chance has intervened. The theory that genius _will_ make its way,
despite all obstacles, is like the popular notion that 'murder will
out,' and other such fancies. We note when events happen which favour
such notions, but we not only do not note--in the very nature of things
it is impossible that we should have the chance of noting--cases
unfavourable to a notion which, after all, is but a part of the general
and altogether erroneous idea that what we think ought to be, will be.
That among millions of men in a civilised community, trained under
multitudinous conditions, for diverse professions, trades, and so
forth, exposed to many vicissitudes of fortune, good and bad, there
should be men from time to time--
Who break their birth's invidious bar,
And grasp the skirts of happy chance,
And breast the blows of circumstance,
And grapple with their evil star,
is no truer proof of the general theory that genius will make its mark,
despite circumstance, than is the occasional occurrence of strange
instances in which murder has been detected despite seemingly perfect
precautions.
It must, however, be in a general sense admitted that mental powers,
like bodily powers, are inherited. If the ancestry of men of genius
could be traced, we should in each case probably find enough, in the
history of some line at least along which descent could be traced, to
account for the possession of special powers, and enough in the history
of that and other lines of descent to account for the other qualities
or characteristics which, combined with those special powers, gave to
the man's whole nature the capacity by which he was enabled to stand
above the average level of his fellow-men. We might, with knowledge at
once wider and deeper than we actually possess of the various families
of each nation, and their relationships, predict in many cases, not
that any given child would prove a genius, but that some one or other
of a family would probably rise to distinction. To predict the advent
of a man of great genius as we predict the approach of an eclipse or a
transit, will doubtless never be in men's power; but it is conceivable
that at some perhaps not very remote epoch, anticipations may be formed
somewhat like those which astronomers are able to make respecting the
recurrence of meteoric showers at particular times and seasons, and
visible in particular regions. Already we know so much as this, that
in certain races of men only can special forms of mental energy, like
special bodily characteristics, be expected to appear. It may well be
that hereafter such anticipations may be limited to special groups of
families.
When we pass from mental to moral qualities, we find ourselves in
the presence of problems which could not be thoroughly dealt with in
these pages. The general question, how far the moral characteristics
of each person born into the world depends on those of the parents, or
more generally of the ancestry, is one involving many considerations
which, perhaps unfortunately, have been associated with religious
questions. And apart from this, the answers to this question have been
found to have a very wide range--from the opinion of those who (like
Miss Martineau) consider that our characters, even where they seem
to undergo changes resulting from the exercise of will, are entirely
due to inheritance, to the view of those who consider, like Heinroth,
that no moral characteristic can possibly be regarded as inherited
in such sort as to modify either responsibility for evil-doing or
credit for well-doing. Probably most will be content to accept a view
between these extremes, without too nicely considering how far moral
responsibility is affected by the influence of inherited tendencies.
There are, however, some illustrations relating to exceptional habits,
which may be mentioned here without bringing in the general question.
I have not referred to insanity in speaking of inherited mental
qualities, because insanity must be regarded as a disease of the moral
rather than of the mental nature. Its origin may be in the mind, as
the origin of mental diseases is in the brain, that is, is in the
body; but the principal manifestations of insanity, those which must
guide us in determining its true position, are unquestionably those
relating to moral habitudes. Insanity is not always, or at least not
always demonstrably hereditary. Esquirol found among 1,375 lunatics 337
unquestionable cases of hereditary transmission. Guislain and others
regard hereditary lunacy as including, roughly, one-fourth of the cases
of insanity. Moreau and others hold that the proportion is greater. It
appears, however, that mental alienation is not the only form in which
the insanity of an ancestor may manifest itself. Dr. Morel gives the
following instructive illustration of the 'varied and odd complications
occurring in the hereditary transmission of nervous disease.' He
attended four brothers belonging to one family. The grandfather of
these children had died insane; their father had never been able to
continue long at anything; their uncle, a man of great intellect and a
distinguished physician, was noted for his eccentricities. Now these
four children, sprung from one stock, presented very different forms
of physical disorder. One of them was a maniac, whose wild paroxysms
occurred periodically. The disorder of the second was melancholy
madness; he was reduced by his stupor to a merely automatic condition.
The third was characterised by an extreme irascibility and suicidal
disposition. The fourth manifested a strong liking for art; but he was
of a timorous and suspicious nature. This story seems in some degree to
give support to the theory that genius and mental aberration are not
altogether alien; that, in fact,
Great wit to madness nearly is allied,
And thin partitions do their bounds divide.
Of the hereditary transmission of idiotcy we naturally have not the
same kind of evidence. Madness often, if not generally, comes on or
shows itself late in life, whereas idiotcy is not often developed in
the adult. Insanity is the diseased or weakened condition of a mind
possessing all the ordinary thinking faculties; idiotcy implies that
some of these faculties are altogether wanting. It has been asserted,
by the way, that idiotcy is a product of civilisation. The civilised
'present, as peoples,' says Dr. Duncan, 'indications of defective vital
force, which are not witnessed among those human beings that live in
a state of nature. There must be something rotten in some parts of
our boasted civilisation: and not only a something which has to do
with our psychology, but a great deal more with our power of physical
persistence. It is a fact that the type of the perfect minded, just
above the highest idiots, or the simpletons, is more distinguishable
amongst the most civilised of the civilised than among those who are
the so-called children of nature. Dolts, boobies, stupids, _et hoc
genus omne_, abound in young Saxondom; but their representatives are
rare amongst the tribes that are slowly disappearing before the white
man.' But it seems barely possible that the difference may be due to
the care with which civilised communities interfere to prevent the
elimination of idiot infants by the summary process of destroying them.
The writer from whom I have just quoted refers to the fact that, even
under the Roman Empire, as during the Republic, idiots were looked upon
as 'useless entities by the practical Roman.' They had no sanctity in
his eyes, and hence their probable rarity; doubtless the unfortunate
children were neglected, and there is much reason for believing that
they were 'exposed.' 'A congenital idiot soon begins to give trouble,'
proceeds Dr. Duncan, 'and to excite unusual attention; and, moreover,
unless extra care is given to it, death is sure to ensue in early
childhood.' May not idiot children in savage communities have an even
worse chance of survival than under the Roman Empire? and may not
dolts, boobies, and stupids, _et hoc genus omne_, among savages, have
such inferior chances in the infantine and later in the adult struggle
for existence, that we may explain thus the comparative rarity of
these varieties in savage communities? It certainly does not seem to
have been proved as yet that civilisation _per se_ is favourable to the
development of insanity.
The liking for strong drink, as is too well known, is often
transmitted. It is remarked by Dr. Howe that 'the children of drunkards
are deficient in bodily and vital energy, and are predisposed by their
very organisation to have cravings for alcoholic stimulants. If they
pursue the course of their fathers, which they have more temptation
to follow and less power to avoid than the children of the temperate,
they add to their hereditary weakness, and increase the tendency to
idiotcy or insanity in their constitution; and this they leave to their
children after them.' Whatever opinion we may form on the general
question of responsibility for offences of commission or of omission,
on this special point all who are acquainted with the facts must
agree, admitting that in some cases of inherited craving for alcoholic
stimulants the responsibility of those who have failed and fallen in
the struggle has been but small. 'The fathers have eaten sour grapes,
and the children's teeth are set on edge.' Robert Collyer of Chicago,
in his noble sermon 'The Thorn in the Flesh,' has well said, 'In the
far-reaching influences that go to every life, and away backward as
certainly as forward, children are sometimes born with appetites
fatally strong in their nature. As they grow up the appetite grows with
them, and speedily becomes a master, the master a tyrant; and by the
time he arrives at manhood, the man is a slave. I heard a man say that
for eight-and-twenty years the soul within him had had to stand like
an unsleeping sentinel, guarding his appetite for strong drink. To be
a man at last under such a disadvantage, not to mention a saint, is as
fine a piece of grace as can well be seen. There is no doctrine that
demands a larger vision than this of the depravity of human nature. Old
Dr. Mason used to say that "as much grace as would make John a saint,
would hardly keep Peter from knocking a man down."'
There are some curious stories of special vices transmitted from
parent to child, which, if true, are exceedingly significant, to say
the least.[19] Gama Machado relates that a lady with whom he was
acquainted, who possessed a large fortune, had a passion for gambling
and passed whole nights at play. 'She died young,' he proceeds, 'of a
pulmonary complaint. Her eldest son who was in appearance the image
of his mother, had the same passion for play. He died of consumption
like his mother, and at the same age; his daughter who resembled him,
inherited the same tastes, and died young.' Hereditary predisposition
to theft, murder, and suicide, has been demonstrated in several cases.
But the world at large is naturally indisposed to recognise congenital
tendency to crime as largely diminishing responsibility for offences
or attempted offences of this kind. So far as the general interests
of the community are concerned, the demonstrated fact that a thief or
murderer has _inherited_ his unpleasant tendency should be a _raison de
plus_ for preventing the tendency from being transmitted any farther.
In stamping out the hereditary ruffian or rascal by life imprisonment,
we not only get rid of the 'grown serpent' but of the worm which
Hath nature that in time would venom breed.
An illustration of the policy at least (we do not say the justice)
of preventive measures in such cases, is shown in the case of a
woman in America, of whom the world may fairly say what Father Paul
remarked to gentle Alice Brown; it 'never knew so criminal a family as
hers.' A young woman of remarkably depraved character, infested, some
seventy years since, the district of the Upper Hudson. At one stage
of her youth she narrowly, and somewhat unfortunately, escaped death.
Surviving, however, she bore many children, who in turn had large
families, insomuch that there are now some eighty direct descendants,
of whom one-fourth are convicted criminals, whilst the rest are
drunkards, lunatics, paupers, and otherwise undesirable members of the
community.
With facts such as these before us, we cannot doubt that in whatever
degree variability may eliminate after awhile peculiar mental or moral
tendencies, these are often transmitted for many generations before
they die out. If it be unsafe to argue that the responsibility of
those inheriting special characteristics is diminished, the duties of
others towards them may justly be considered to be modified. Other
duties than the mere personal control of tendencies which men may
recognise in themselves are also introduced. If a man finds within
himself an inherent tendency towards some sin, which yet he utterly
detests, insomuch that while the spirit is willing the flesh is weak
or perchance utterly powerless, he must recognise in his own life a
struggle too painful and too hopeless to be handed down to others.
As regards our relations to families in which criminal tendencies
have been developed, either through the negligence of those around
(as in certain dens in London where for centuries crime has swarmed
and multiplied), or by unfortunate alliances, we may 'perceive here
a divided duty.' It has been remarked that 'we do not set ourselves
to train tigers and wolves into peaceful domestic animals; we seek to
extirpate them,' and the question has been asked, 'why should we act
otherwise with beings, who, if human in form, are worse than wild
beasts?' 'To educate the son of a garotter or a "corner-man" into an
average Englishman,' may be 'about as promising a task as to train
one of the latter into a Newton or a Milton.' But we must not too
quickly despair of a task which may be regarded as a duty inherited
from those who in past generations neglected it. There is no hope of
the reversion of tiger or wolf to less savage types, for, far back as
we can trace their ancestry, we find them savage of nature. With our
criminal families the case is not so utterly hopeless. Extirpation
being impossible (though easily talked of) without injustice which
would be the parent of far greater troubles even than our criminal
classes bring upon us, we should consider the elements of hope which
the problem unquestionably affords. By making it the manifest interest
of our criminal population to scatter, or, failing that, by leaving
them no choice in the matter, the poison in their blood may before many
generations be eradicated, not by wide-spreading merely, but because
of the circumstance that only the better sort among them would have
(when scattered) much chance of rearing families as well as of escaping
imprisonment.
FOOTNOTES:
[Footnote 15: It is said by Ribot that of all the features the nose is
the one which heredity preserves best.]
[Footnote 16: Shakspeare, who was bald young (and, so far as one
can judge from his portraits, had a good set of teeth), suggests a
correlation between hairiness and want of wit, which is at least
likely to be regarded by those who 'wear his baldness while they're
young' as a sound theory. 'Why,' asks Antipholus of Syracuse, 'is Time
such a niggard of hair, being, as it is, so plentiful an excrement?'
'Because,' says Dromio of Syracuse, 'it is a blessing that he bestows
on beasts; and what he hath scanted men in hair he hath given them in
wit.']
[Footnote 17: While penning the above lines I have been reminded of an
experience of my own, which I had never before thought of as connected
with the subject of heredity; yet it seems not unlikely that it may be
regarded as a case in point. During the infancy of my eldest son it
so chanced that the question of rest at night, and consequently the
question of finding some convenient way of keeping the child quiet,
became one of considerable interest to me. Cradle-rocking was effective
but carried on in the usual way prevented my own sleep, though causing
the child to sleep. I devised, however, a way of rocking the cradle
with the foot, which could be carried on in my sleep, after a few
nights' practice. Now it is an odd coincidence (only, perhaps) that the
writer's next child, a girl, had while still an infant a trick which I
have noticed in no other case. She would rock herself in the cradle by
throwing the right leg over the left at regular intervals, the swing of
the cradle being steadily kept up for many minutes, and being quite as
wide in range as a nurse could have given. It was often continued when
the child was asleep.
Since writing the above, I have learned from my eldest daughter, the
girl who as a child had the habit described, that a recent little
brother of hers, one of twins, and remarkably like her, had the same
habit, rocking his own cradle so vigorously as to disturb her in the
next room with the noise. These two only of twelve children have had
this curious habit; but as this child is thirteen years younger than
she is, the force of the coincidence in point of time is to some degree
impaired.]
[Footnote 18: See my _Science Byeways_, p. 337 _et seq._]
[Footnote 19: The following statement from the researches of
Brown-Sequard seems well worth noting in this connection:--'In the
course of his masterly experimental investigations into the functions
of the nervous system he discovered that, after a particular lesion
of the spinal cord of guinea-pigs, a slight pinching of the skin of
the face would throw the animal into a kind of epileptic convulsion.
That this artificial epilepsy should be constantly producible in
guinea-pigs, and not in any other animals experimented on, was in
itself sufficiently singular; and it was not less surprising that the
tendency to it persisted after the lesion of the spinal cord seemed
to have been entirely recovered from. But it was far more wonderful
that the offspring of these epileptic guinea-pigs showed the same
predisposition, without having been themselves subjected to any lesion
whatever; whilst no such tendency showed itself in any of the large
number of young bred by the same accurate observer from parents that
had not thus been operated on.']
_BODILY ILLNESS AS A MENTAL STIMULANT._
During special states of disease the mind sometimes develops faculties
such as it does not possess when the body is in full health. Some of
the abnormal qualities thus exhibited by the mind seem strikingly
suggestive of the possible acquisition by the human race of similar
powers under ordinary conditions. For this reason, though we fear
there is no likelihood at present of any practical application of the
knowledge we may obtain on this subject, it seems to me that there is
considerable interest in examining the evidence afforded by the strange
powers which the mind occasionally shows during diseases of the body,
and especially during such diseases as are said, in unscientific but
expressive language, to lower the tone of the nervous system.
We may begin by citing a case which seems exceedingly significant. Miss
H. Martineau relates that a congenital idiot, who had lost his mother
when he was less than two years old, when dying, 'suddenly turned
his head, looked bright and sensible, and exclaimed, in a tone never
heard from him before, "Oh my mother! how beautiful!" and sank down
again--dead.' Dr. Carpenter cites this as a case of abnormal memory,
illustrating his thesis that the basis of recollection 'may be laid at
a very early period of life.' But the story seems to contain a deeper
meaning. The poor idiot not only recalled a long-past time, a face
that he had not seen for years except in dreams, but he gained for a
moment a degree of intelligence which he had not possessed when in
health. The quality of his brain was such, it appears, that with the
ordinary activity of the circulation, the ordinary vitality of the
organ, mental action was uncertain and feeble; but when the circulation
had all but ceased, when the nervous powers were all but prostrate, the
feeble brain, though it may have become no stronger actually, became
relatively stronger, in such sort that for the time specified, a mere
moment before dissolution, the idiot became an intelligent being.
A somewhat similar case is on record in which an insane person, during
that stage of typhus fever in which sane persons are apt to become
delirious, became perfectly sane and reasonable, his insanity returning
with returning health. Persons of strongest mind in health are often
delirious for a short time before death. Since, then, the idiot in the
same stage of approaching dissolution may become intelligent, while
the insane may become sane under the conditions which make the sane
become delirious, we recognise a relationship between the mental and
bodily states which might be of considerable use in the treatment of
mental diseases. It may well be that conditions of the nervous system
which are to be avoided by persons of normal mental qualities may be
advantageously superinduced in the case of those of abnormally weak or
abnormally violent mind. It is noteworthy that different conditions
would seem to be necessary for the idiotic and for the insane, if
the cases cited sufficed to afford basis for generalisation. For the
idiot of Miss Martineau's story became intelligent during the intense
depression of the bodily powers immediately preceding dissolution,
whereas the insane person became sane during that height of fever when
delirium commonly makes its appearance.
Sir H. Holland mentions a case which shows that great bodily depression
may affect a person of ordinary clear and powerful mind. 'I descended
on one and the same day,' he says, 'two very deep mines in the Hartz
Mountains, remaining some hours under ground in each. While in the
second mine, and exhausted both from fatigue and inanition, I felt the
utter impossibility of talking longer with the German Inspector who
accompanied me. Every German word and phrase deserted my recollection;
and it was not until I had taken food and wine, and been some time at
rest, that I regained them again.'
A change in the mental condition is sometimes a sign of approaching
serious illness, and is felt to be so by the person experiencing it.
An American writer, Mr. Butterworth, quotes the following description
given by a near relative of his who was suffering from extreme nervous
debility. 'I am in constant fear of insanity,' she said, 'and I wish
I could be moved to some retreat for the insane. I understand my
condition perfectly; my reason does not seem to be impaired; but I can
think of _two things at the same time_. This is an indication of mental
unsoundness, and is a terror to me. I do not seem to have slept at all
for the last six months. If I sleep, it must be in a succession of
vivid dreams that destroy all impression of somnolence. Since I have
been in this condition I seem to have a very vivid impression of what
happens to my children who are away from home, and I am often startled
to hear that these impressions are correct. I seem to have also a
certain power of anticipating what one is about to say, and to read
the motives of others. I take no pleasure in this strange increase of
mental power; it is all unnatural. I cannot live in this state long,
and I often wish I were dead.'
It must, however, be remembered that persons who are in a state of
extreme nervous debility, not only possess at times abnormal mental
qualities, but are also affected morally. As Huxley has well remarked
of some stories bearing on spiritualism, they come from persons
who can hardly be trusted even according to their own account of
themselves. Mr. Butterworth's relation described a mental condition
which, even if quite correctly pictured as she understood it, may yet
be explained without believing that any very marvellous increase had
taken place in her mental powers. Among the vivid impressions which
she constantly had of what might be happening to her children away
from home, it would have been strange if some had not been correct.
The power of anticipating what others were about to say is one which
many imagine they have, mistaking the occasional coincidence between
their guesses and what has been next said, for indications of a power
which in reality they do not possess. And so also with regard to the
motives of others. Many are apt, especially when out of health, to
guess at others' motives, sometimes rightly, but oftener very wrongly,
yet always rightly in their own belief, no matter what evidence may
presently appear to the contrary.
The case cited by Mr. Butterworth affords evidence rather of the
unhealthy condition of the patient's mind than of abnormal powers,
except as regards the power of thinking of two things at the same
time, which we may fairly assume was not ordinarily possessed by its
relative. It is rather difficult to define such a power, however.
Several persons have apparently possessed the power, showing it by
doing two things at the same time which both appear to require thought,
and even close attention. Julius Cæsar, for example, could write on one
subject and dictate on another simultaneously. But in reality, even in
cases such as these, the mind does not think of two things at once. It
simply takes them in turn, doing enough with each, in a short time, a
mere instant, perhaps, to give work to the pen or to the voice, as the
case may be, for a longer time. When Cæsar was writing a sentence, he
was not necessarily thinking of what he was writing. He had done the
thinking part of the work before; and was free, while continuing the
mere mechanical process of writing, to think of matter for dictation
to his secretary. So also while he was speaking he was free to think
of matter for writing. If, indeed, the thought for each sentence of
either kind had occupied an appreciable time, there would have been
interruptions of his writing, if not of his dictation (dictation is
not commonly a continuous process under any circumstances, even when
shorthand writers take down the words). But a practised writer or
speaker can in a moment form a sentence which shall occupy a minute in
writing and several seconds in speaking.
I certainly do not myself claim the power of thinking of two things
at once,--nay, I believe that no one ever had or could have such a
power: yet I find it perfectly easy, when lecturing, to arrange the
plan for the next ten minutes' exposition of a scientific subject, and
to adopt the words themselves for the next twenty seconds or so, while
continuing to speak without the least interruption. I can also work out
a calculation on the black-board while continuing to speak of matters
outside the subject of the calculation. It is more a matter of habit
than an indication of any mental power, natural or acquired, to speak
or write sentences; even of considerable length, after the mind has
passed on to other matters. In a similar way some persons can write
different words with the right and left hands, and this, too, while
speaking of other matters. (I have seen this done by Professor Morse,
the American naturalist, whose two hands added words to the diagrams he
had drawn while his voice dealt with other parts of the drawing: to add
to the wonder, too, he wrote the words indifferently from right to left
or from left to right.) In reality the person who thus does two things
at once is no more thinking of two things at once than a clock is, when
the striking and the working machinery are both in action at the same
time.[20]
As an illustration of special mental power shown in health, by a person
whose mental condition in illness we shall consider afterwards, Sir
Walter Scott may be mentioned. The account given by his amanuensis
has seemed surprising to many, unfamiliar with the nature of literary
composition (at least after long practice), but is in reality such as
anyone who writes much can quite readily understand, or might even have
known must necessarily be correct. 'His thoughts,' says the secretary
to whom Scott dictated his _Life of Napoleon Buonaparte_, 'flowed
easily and felicitously, without any difficulty to lay hold of them
or to find appropriate language' (which, by the way, is more than all
would say who had read Scott's _Life of Buonaparte_, and certainly more
than can be said of his secretary, unless it really was a familiar
experience with him to be unable to lay hold of his thoughts). 'This
was evident by the absence of all solicitude (_miseria cogitandi_)
from his countenance. He sat in his chair, from which he rose now and
then, took a volume from the book-case, consulted it, and restored it
to the shelf--all without intermission in the current of ideas, which
continued to be delivered with no less readiness than if his mind had
been wholly occupied with the words he was uttering. It soon became
apparent to me, however, that he was carrying on two distinct trains
of thought, one of which was already arranged and in the act of being
spoken, while at the same time he was in advance, considering what
was afterwards to be said. This I discovered' (he should rather have
said, 'this I was led to infer') 'by his sometimes introducing a word
which was wholly out of place--_entertained_ instead of _denied_, for
example--but which I presently found to belong to the next sentence,
perhaps four or five lines further on, which he had been preparing at
the very moment when he gave me the words of the one that preceded
it.' In the same way I have often unconsciously substituted one word
for another in lecturing, the word used always belonging to a later
sentence than the word intended to be used. I have noticed also this
peculiarity, that when a substitution of this kind has been once made,
an effort is required to avoid repeating the mistake, even if it be
not repeated quite unconsciously to the end of the discourse. In this
way, for example, I once throughout an entire lecture used the word
'heavens' for the word 'screen' (the screen on which lantern pictures
were shown). A similar peculiarity may be noticed with written errors.
Thus in my treatise on a scientific subject, in which the utmost care
had been given to minute points of detail, I once wrote 'seconds' for
'minutes' throughout several pages--in fact, from the place where
first the error was made, to the end of the chapter. (See the _first_
edition of my _Transits of Venus_, pp. 131-136, noting as an additional
peculiarity that the whole object of the chapter in which this mistake
was made was to show how many minutes of difference existed between the
occurrence of certain events.)
An even more curious instance of a mistake arising from doing one
thing while thinking of another occurred to me fourteen years ago. I
was correcting the proof-sheets of an astronomical treatise in which
occurred these words: 'Calling the mean distance of the earth 1,
Saturn's mean distance is 9·539; again, calling the earth's period
1, Saturn's mean period is 29·457:--now what relation exists between
these numbers 9·539 and 29·457 and their powers? The first is less
than the second, but the square of the first is plainly greater than
the second; we must therefore try higher powers, &c. &c.' The passage
was quite correct as it stood, and if the two processes by which I was
correcting verbal errors and following the sense of the passage had
been really continuous processes of thought, unquestionably the passage
would have been left alone. If the passage had been erroneous and had
been simply left in that condition the case would have been one only
too familiar to those who have had occasion to correct proofs. But
what I actually did was deliberately to make nonsense of the passage
while improving the sound of the second sentence. I made it run,
'the first is less than the second, but the square of the first is
plainly greater than the square of the second,' the absurdity of which
statement a child would detect. If the first proof in its correct form,
with the incorrect correction carefully written down in the margin,
had not existed when, several months later, the error was pointed out
in the _Quarterly Journal of Science_, I should have felt sure that
I had written the words wrongly at the outset. For blunders such as
this are common enough. But that I should deliberately have taken a
correctly worded sentence and altered it into utter absurdity I could
not, but for the evidence, have believed to be possible. The case
plainly shows that not only may two things be done at once when the
mind, nevertheless, is thinking only of one, but that something may be
done which suggests deliberate reflection when in reality the mind is
elsewhere or not occupied at all. For in this case both the processes
on which I was engaged were manifestly carried on without thought,
one being purely mechanical and the other, though requiring thought if
properly attended to, being so imperfectly effected as to show that no
thought was given to it.
To return to Sir Walter Scott. It is known but too well that during
the later years of his life there came with bodily prostration a great
but not constant failure of his mental powers. Some of the phenomena
presented during this part of his career are strikingly illustrative of
abnormal mental action occurring even at times when the mental power
is on the whole much weakened. _The Bride of Lammermoor_, though not
one of the best of Scott's novels, is certainly far above such works
as _Count Robert of Paris_, _The Betrothed_, and _Castle Dangerous_.
Its popularity may perhaps be attributed chiefly to the deep interest
of the 'ower true tale' on which it is founded: but some of the
characters are painted with exceeding skill. Lucy herself is almost
a nonentity, and Edgar is little more than a gloomy, unpleasant man,
made interesting only by the troubles which fall on him. But Caleb
Balderstone and Ailsie Gourlay stand out from the canvas as if alive;
they are as lifelike and natural, yet as thoroughly individualised
as Edie Ochiltree and Meg Merrilies. The novel neither suggested
when it first appeared, nor has been regarded even after the facts
became known, as suggesting that Scott, when he wrote it, was in bad
health. Yet it was produced under pressure of severe illness, and when
Scott was at least in this sense unconscious, that nothing of what
he said and did in connection with the work was remembered when he
recovered. 'The book,' says James Ballantyne, 'was not only written,
but published, before Mr. Scott was able to rise from his bed; and he
assured me that when it was first put into his hands in a complete
shape, _he did not recollect one single incident, character, or
conversation it contained_! He did not desire me to understand, nor did
I understand, that his illness had erased from his memory the original
incidents of the story, with which he had been acquainted from his
boyhood. These remained rooted where they had ever been; or, to speak
more explicitly, he remembered the general facts of the existence of
the father and mother, of the son and daughter, of the rival lovers,
of the compulsory marriage, and the attack made by the bride upon the
hapless bridegroom, with the general catastrophe of the whole. _All
these things he recollected_, just as he did before he took to his bed;
_but he literally recollected nothing else_--not a single character
woven by the romancer, not one of the many scenes and points of humour,
not _anything with which he was himself connected_, as the writer of
the work.
Later, when Scott was breaking down under severe and long-continued
labour, and first felt the approach of the illness which ultimately
ended in death, he experienced strange mental phenomena. In his diary
for February 17, 1829, he notes that on the preceding day, at dinner,
though in company with two or three old friends, he was haunted by 'a
sense of pre-existence,' a confused idea that nothing that passed was
said for the first time; that the same topics had been discussed, and
that the same persons had expressed the same opinions before. 'There
was a vile sense of a want of reality in all that I did or said.'
Dr. Reynolds related to Dr. Carpenter a case in which a Dissenting
minister, who was in apparently sound health, was rendered apprehensive
of brain-disease--though, as it seemed, without occasion--by a lapse
of memory similar to that experienced by Sir Walter Scott. He 'went
through an entire pulpit service on a certain Sunday morning with the
most perfect consistency--his choice of hymns and lessons, and his
_extempore_ prayer being all related to the subject of his sermon. On
the following Sunday morning he went through the introductory part of
the service in precisely the same manner--giving out the same hymns,
reading the same lessons, and directing the _extempore_ prayer in the
same channel. He then gave out the same text and preached the very same
sermon as he had done on the previous Sunday. When he came down from
the pulpit, it was found that he had not the smallest remembrance of
having gone through precisely the same service on the previous Sunday;
and when he was assured of it, he felt considerable uneasiness lest
his lapse of memory should indicate some impending attack of illness.
None such, however, supervened; and no _rationale_ can be given of
this curious occurrence, the subject of it not being liable to fits
of "absence of mind" and not having had his thoughts engrossed at the
time by any other special pre-occupation.' It is possible that the
explanation here is the simple one of mere coincidence. Whether this
explanation is available or not would depend entirely on the question
whether the preacher's memory was ordinarily trustworthy or not,
whether in fact he would remember the arrangements, prayers, sermon,
&c., he had given on any occasion. These matters becoming, after long
habit, almost automatic, it might very well happen that the person
going through such duties would remember them no longer and no better
than one who had been present when they were performed, and who had
not paid special attention to them. That if he had thus unconsciously
carried out his duties on one Sunday he should (being to this degree
forgetful) conduct them in precisely the same way on the next Sunday,
would rather tend to show that his mental faculties were in excellent
working order than the reverse. Wendell Holmes tells a story which
effectively illustrates my meaning; and he tells it so pleasantly (as
usual) that I shall quote it unaltered. 'Sometimes, but rarely,' he
says, 'one may be caught making the same speech twice over, and yet be
held blameless. Thus a certain lecturer' (Holmes himself, doubtless),
'after performing in an inland city, where dwells a _littératrice_
of note, was invited to meet her and others over the social tea-cup.
She pleasantly referred to his many wanderings in his new occupation.
"Yes," he replied, "I am like the huma, the bird that never lights,
being always in the cars, as he is always on the wing." Years elapsed.
The lecturer visited the same place once more for the same purpose.
Another social cup after the lecture, and a second meeting with the
distinguished lady. "You are constantly going from place to place,"
she said. "Yes," he answered, "I am like the huma," and finished the
sentence as before. What horror when it flashed over him that he had
made this fine speech, word for word, twice over! Yet it was not true,
as the lady might perhaps have fairly inferred, that he had embellished
his conversation with the huma daily during that whole interval of
years. On the contrary, he had never once thought of the odious fowl
until the recurrence of precisely the same circumstances brought up
precisely the same idea.' He was not in the slightest degree afraid
of brain-disease. On the contrary, he considered the circumstance
indicative of good order in the mental mechanism. 'He ought to have
been proud,' says Holmes, speaking for him, and meaning no doubt that
he _was_ proud, 'of the accuracy of his mental adjustments. _Given
certain factors, and a sound brain should always evolve the same fixed
product with the certainty of Babbage's calculating machine._'
Somewhat akin to the unconscious recurrence of mental processes
after considerable intervals of time is the tendency to imitate the
actions of others as though sharing in their thoughts, and according
to many _because_ mind acts upon mind. This tendency, though not
always associated with disease, is usually a sign of bodily illness.
Dr. Carpenter mentions the following singular case, but rather as
illustrating generally the influence of suggestions derived from
external sources in determining the current of thought, than as showing
how prone the thoughts are to run in undesirable currents when the
body is out of health:--'During an epidemic of fever, in which an
active delirium had been a common symptom, it was observed that many
of the patients of one particular physician were possessed by a strong
tendency to throw themselves out of the window, whilst no such tendency
presented itself in unusual frequency in the practice of others. The
author's informant, Dr. C., himself a distinguished professor in the
university, explained the tendency of what had occurred within his own
knowledge; he having been himself attacked by the fever, and having
been under the care of this physician, his friend and colleague, Dr.
A. Another of Dr. A.'s patients whom we shall call Mr. B., seems to
have been the first to make the attempt in question; and impressed
with the necessity of taking due precautions, Dr. A. then visited Dr.
C., _in whose hearing_ he gave directions to have the windows properly
secured, as Mr. B. had attempted to throw himself out. Now Dr. C.
distinctly remembers, that although he had not previously experienced
any such desire, it came upon him with great urgency as soon as ever
the idea was thus suggested to him; his mind being just in that state
of incipient delirium which is marked by the temporary dominance of
some one idea, and by the want of volitional power to withdraw the
attention from it. And he deemed it probable that, as Dr. A. went on to
Mr. D., Mr. E., &c., and gave similar directions, a like desire would
be excited in the minds of all those who might happen to be in the same
impressible condition.' The case is not only interesting as showing
how the mind in disease receives certain impressions more strongly
than in health, and in a sense may thus be said to possess for the
time an abnormal power, but it affords a useful hint to doctors and
nurses, who do not always (the latter indeed scarcely ever) consider
the necessity of extreme caution when speaking about their patients and
in their presence. It is probable that a considerable proportion of the
accidents, fatal and otherwise, which have befallen delirious patients
might be traced to incautious remarks made in their hearing by foolish
nurses or forgetful doctors.
In some cases doctors have had to excite a strong antagonistic feeling
against tendencies of this kind. Thus Zerffi relates that an English
physician was once consulted by the mistress of a ladies' school where
many girls had become liable to fits of hysterics. He tried several
remedies, but in vain. At last, justly regarding the epidemic as
arising from the influence of imagination on the weaker girls (one
hysterical girl having infected the others), he determined to exert
a stronger antagonistic influence on the weak minds of his patients.
He therefore remarked casually to the mistress of the school, in the
hearing of the girls, that he had now tried all methods but one, which
he would try, as a last resource, when next he called--'the application
of a red-hot iron to the spine of the patients so as to quiet their
nervously-excited systems.' 'Strange to say,' remarks Zerffi--meaning,
no doubt, 'it is hardly necessary to say that'--'the red-hot iron was
never applied, for the hysterical attacks ceased as if by magic.'
In another case mentioned by Zerffi, a revival mania in a large school
near Cologne was similarly brought to an abrupt end. The Government
sent an inspector. He found that the boys had visions of Christ, the
Virgin, and departed saints. He threatened to close the school if
these visions continued, and thus to exclude the students from all the
prospects which their studies afforded them. 'The effect was as magical
as the red-hot iron remedy--the revivals ceased as if by magic.'
The following singular cases are related in Zimmermann's _Solitude_:--A
nun, in a very large convent in France, began to mew like a cat. At
last all the nuns began to mew together every day at a certain time,
and continued mewing for several hours together. This daily cat-concert
continued, until the nuns were informed that a company of soldiers
was placed by the police before the entrance to the convent, and that
the soldiers were provided with rods with which they would whip the
nuns until they promised not to mew any more,' ... 'In the fifteenth
century, a nun in a German convent fell to biting her companions. In
the course of a short time all the nuns of this convent began biting
each other. The news of this infatuation among the nuns soon spread,
and excited the same elsewhere; the biting mania passing from convent
to convent through a great part of Germany. It afterwards visited the
nunneries of Holland, and even spread as far as Rome.' No suggestion
of bodily disease is made in either case. But anyone who considers
how utterly unnatural is the manner of life in monastic communities
will not need the evidence derived from the spread of such preposterous
habits to be assured that in convents the perfectly sane mind in a
perfectly healthy body must be the exception rather than the rule.
The dancing mania, which spread through a large part of Europe in the
fourteenth and fifteenth centuries, although it eventually attacked
persons who were seemingly in robust health, yet had its origin in
disease. Dr. Hecker, who has given the most complete account we have
of this strange mania, in his _Epidemics of the Middle Ages_, says
that when the disease was completely developed the attack commenced
with epileptic convulsions. 'Those affected fell to the ground
senseless, panting and labouring for breath. They foamed at the
mouth, and suddenly springing up began their dance amidst strange
contortions. They formed circles hand in hand, and appearing to have
lost all control over their senses continued dancing, regardless of the
bystanders, for hours together, in wild delirium, until at length they
fell to the ground in a state of exhaustion. They then complained of
extreme oppression, and groaned as if in the agonies of death, until
they were swathed in clothes bound tightly round their waists; upon
which they again recovered, and remained free from complaint until
the next attack.... While dancing they neither saw nor heard, being
insensible to external impressions through the senses; but they were
haunted by visions, their fancies conjuring up spirits, whose names
they shrieked out; and some of them afterwards asserted that they felt
as if they had been immersed in a stream of blood, which obliged them
to leap so high. Others during the paroxysm saw the heavens open,
and the Saviour enthroned with the Virgin Mary, according as the
religious notions of the age were strangely and variously reflected
in their imaginations.' The epidemic attacked people of all stations,
but especially those who led a sedentary life, such as shoemakers and
tailors; yet even the most robust peasants finally yielded to it. They
'abandoned their labours in the fields as if they were possessed by
evil spirits, and those affected were seen assembling indiscriminately
from time to time, at certain appointed places, and unless prevented
by the lookers-on, continued to dance without intermission, until
their very last breath was expended. Their fury and extravagance of
demeanour so completely deprived them of their senses, that many
of them dashed their brains out against the walls and corners of
buildings, or rushed headlong in rapid rivers, where they found a
watery grave. Roaring and foaming as they were, the bystanders could
only succeed in restraining them by placing benches and chairs in their
way, so that by the high leaps they were thus tempted to take, their
strength might be exhausted. As soon as this was the case they fell,
as it were, lifeless to the ground, and by very slow degrees recovered
their strength. Many there were who even with all this exertion had not
expended the violence of the tempest which raged within them; but awoke
with newly revived powers, and again and again mixed with the crowd of
dancers; until at length the violent excitement of their disordered
nerves was allayed by the great involuntary exertion of their limbs,
and the mental disorder was calmed by the exhaustion of the body. The
cure effected by these stormy attacks was in many cases so perfect,
that some patients returned to the factory or plough, as if nothing
had happened. Others, on the contrary, paid the penalty of their folly
by so total a loss of power, that they could not regain their former
health, even by the employment of the most strengthening remedies.'
It may be doubted, perhaps, by some whether such instances as these
illustrate so much the state to which the mind is reduced when the body
is diseased, as the state to which the body is reduced when the mind
is diseased, though, as we have seen, the dancing mania when fully
developed followed always on bodily illness. In the cases we now have
to deal with, the diseased condition of the body was unmistakable.
Mrs. Hemans on her deathbed said that it was impossible for imagination
to picture or pen to describe the delightful visions which passed
before her mind. They made her waking hours more delightful than those
passed in sleep. It is evident that these visions had their origin
in the processes of change affecting the substance of the brain as
the disease of the body progressed. But it does not follow that the
substance of the brain was undergoing changes necessarily tending
to its ultimate decay and dissolution. Quite possibly the changes
were such as might occur under the influence of suitable medicinal
or stimulant substances, and without any subsequent ill effects.
Dr. Richardson, in an interesting article on ether-drinking and
extra-alcoholic intoxication (_Gentleman's Magazine_ for October),
makes a remark which suggests that the medical men of our day look
forward to the discovery of means for obtaining some such influence
over the action of the brain. After describing the action of methylic
and ethylic ethers in his own case, he says: 'They who have felt
this condition, who have lived as it were in another life, however
transitorily, are easily led to declare with Davy that "nothing
exists but thoughts! the universe is composed of impressions, ideas,
pleasures, and pains!" I believe it is so, and that we might by
scientific art, and there is such an art, learn to live altogether in
a new sphere of impressions, ideas, pleasures, and pains.' But stay,'
he adds, as if he had said too much, 'I am anticipating, unconsciously,
something else that is in my mind. The rest is silence; I must return
to the world in which we now live, and which all know.'
Mr. Butterworth mentions the case of the Rev. William Tennent, of
Freehold, New Jersey, as illustrative of strange mental faculties
possessed during disease. Tennent was supposed to be far gone in
consumption. At last, after a protracted illness, he seemingly died,
and preparations were made for his funeral. Not only were his friends
deceived, but he was deceived himself, for he thought he was dead, and
that his spirit had entered Paradise. 'His soul, as he thought, was
borne aloft to celestial altitudes, and was enraptured by visions of
God and all the hosts of Heaven. He seemed to dwell in an enchanted
region of limitless light and inconceivable splendour. At last an
angel came to him and told him that he must go back. Darkness, like an
overawing shadow, shut out the celestial glories; and, full of sudden
horror, he uttered a deep groan. This dismal utterance was heard by
those around him, and prevented him from being buried alive, after all
the preparations had been made for the removal of the body.'
We must not fall into the mistake of supposing, however, as many seem
to do, that the visions seen under such conditions, or by ecstatics,
really present truths of which the usual mental faculties could not
become cognisant. We have heard such cases as the deathbed visions of
Mrs. Hemans, and the trance visions of Tennent, urged as evidence in
favour of special forms of doctrine. We have no thought of attacking
these, but assuredly they derive no support from evidence of this
sort. The dying Hindoo has visions which the Christian would certainly
not regard as heaven-born. The Mahomedan sees the plains of Paradise,
peopled by the houris of his heaven, but we do not on that account
accept the Koran as the sole guide to religious truth. The fact is,
that the visions pictured by the mind during the disease of the body,
or in the ecstatic condition, have their birth in the mind itself,
and take their form from the teachings with which that mind has been
imbued. They may, indeed, seem utterly unlike those we should expect
from the known character of the visionary, just as the thoughts of a
dying man may be, and often are, very far removed from the objects
which had occupied all his attention during the later years of his
life. But if the history of the childhood and youth of an ecstatic
could be fully known, or if (which is exceedingly unlikely) we could
obtain a strictly truthful account of such matters from himself, we
should find nearly every circumstance of his visions explained, or at
least an explanation suggested. For, after all, much which would be
necessary to exactly show the origin of all he saw, would be lost,
since the brain retains impressions of many things of which the
conscious memory has entirely passed away.
The vivid picturing of forgotten events of life is a familiar
experience of the opium-eater. Thus De Quincey says: 'The minutest
incidents of childhood or forgotten scenes of later years, were often
revived. I could not be said to recollect them, for if I had been told
of them when waking, I should not have been able to acknowledge them as
part of my past experience. But placed as they were before me in dreams
like intuitions, and clothed in all their evanescent circumstances and
accompanying feelings, I recognised them instantaneously.' A similar
return of long-forgotten scenes and incidents to the mind may be
noticed, though not to the same degree, when wine has been taken in
moderate quantity after a long fast.
The effects of hachisch are specially interesting in this connection,
because, unless a very powerful dose has been taken, the hachischin
does not wholly lose the power of introspection, so that he is able
afterwards to recall what has passed through his mind when he was under
the influence of the drug. Now Moreau, in his interesting _Etudes
Psychologiques_ (_Du Hachich et d'Aliénation Mentale_), says that the
first result of a dose sufficient to produce the _hachisch fantasia_
is a feeling of intense happiness. 'It is really _happiness_ which is
produced by the hachisch; and by this simply an enjoyment entirely
moral, and by no means sensual as we might be induced to suppose. This
is surely a very curious circumstance; and some remarkable inferences
might be drawn from it; this, for instance, among others--that every
feeling of joy and gladness, even when the cause of it is exclusively
moral--that those enjoyments which are least connected with material
objects, the most spiritual, the most ideal, may be nothing else than
sensations purely physical, developed in the interior of the system,
as are those procured by hachisch. At least so far as relates to that
of which we are internally conscious, there is no distinction between
these two orders of sensations, in spite of the diversity in the
causes to which they are due; for the hachisch-eater is happy, not like
the gourmand or the famished man when satisfying his appetite, or the
voluptuary in gratifying his amative desires, but like him who hears
tidings which fill him with joy, like the miser counting his treasures,
the gambler who is successful at play, or the ambitious man who is
intoxicated with success.'
My special object, however, in noting the effects of opium and
hachisch, is rather to note how the mental processes or faculties
observed during certain states of disease may be produced artificially,
than to enter into the considerations discussed by Dr. Moreau. It is
singular that while the Mohamedan order of Hachischin (or Assassins)
bring about by the use of their favourite drug such visions as
accompany the progress of certain forms of disease, the Hindoo devotees
called the Yogi are able to produce artificially the state of mind and
body recognised in cataleptic patients. The less-advanced Yogi can
only enter the state of abstraction called reverie; but the higher
orders can simulate absolute inanition, the heart apparently ceasing
to beat, the lungs to act, and the nerves to convey impressions to
the brain, even though the body be subjected to processes which would
cause extreme torture under ordinary conditions. 'When in this state,'
says Carpenter, 'the Yogi are supposed to be completely possessed by
Brahma, "the supreme soul," and to be incapable of sin in thought,
word, or deed.' It has been supposed that this was the state into which
those entered who in old times were resorted to as oracles. But it has
happened that in certain stages of disease the power of assuming the
death-like state has been possessed for a time. Thus Colonel Townsend,
who died in 1797, we read, had in his last sickness the extraordinary
power of apparently dying and returning to life again at will. 'I found
his pulse sink gradually,' says Dr. Cheyne, who attended him, 'so that
I could not feel it by the most exact or nice touch. Dr. Raymond could
not detect the least motion of the heart, nor Dr. Skrine the least soil
of the breath upon the bright mirror held to the mouth. We began to
fear he was actually dead. He then began to breathe softly.' Colonel
Townsend repeated the experiment several times during his illness, and
could always render himself insensible at will.
Lastly, I may mention a case, which, however, though illustrating
in some degree the influence of bodily illness on the mind, shows
still more strikingly how the mind may influence the body--that of
Louise Lateau, the Belgian peasant. This girl had been prostrated by
a long and exhausting illness, from which she recovered rapidly after
receiving the sacrament. This circumstance made a strong impression
on her mind. Her thoughts dwelt constantly on the circumstances
attending the death of Christ. At length she noticed that, on every
Friday, blood came from a spot in her left side. 'In the course of a
few months similar bleeding spots established themselves on the front
and back of each hand, and on the upper surface of each foot, while
a circle of small spots formed in the forehead, and the hæmorrhage
from these recurred every Friday, sometimes to a considerable amount.
About the same time, fits of ecstasy began to occur, commencing every
Friday between eight and nine in the morning, and ending about six
in the evening; interrupting her in conversation, in prayer, or in
manual occupations. This state,' says Dr. Carpenter, 'appears to have
been intermediate between that of the biologised and that of the
hypnotised subject; for whilst as unconscious as the latter of all
sense-impressions, she retained, like the former, a recollection of
all that had passed through her mind during the ecstasy. She described
herself as suddenly plunged into a vast flood of bright light, from
which more or less distinct forms began to evolve themselves; and she
then witnessed the several scenes of the Passion successively passing
before her. She minutely described the cross and the vestments, the
wounds, the crown of thorns about the head of the Saviour, and gave
various details regarding the persons about the cross, the disciples,
holy women, Jews and Roman soldiers. And the progress of her vision
might be traced by the succession of actions she performed at various
stages of it: most of these movements were expressive of her own
emotions, whilst regularly about three in the afternoon she extended
her limbs in the form of a cross. The fit terminated with a state of
extreme physical prostration; the pulse being scarcely perceptible, the
breathing slow and feeble, and the whole surface bedewed with a cold
perspiration. After this state had continued for about ten minutes, a
return to the normal condition rapidly took place.'
There seems no reason for supposing that there was any deceit on the
part of Louise Lateau herself, though that she was self-deceived no
one can reasonably doubt. Of course many in Belgium, especially the
more ignorant and superstitious (including large numbers of the clergy
and of religious orders of men and women), believed that her ecstasies
were miraculous, and no doubt she believed so herself. But none of the
circumstances observed in her case, or related by her, were such as
the physiologist would find any difficulty in accepting or explaining.
Her visions were such as might have been expected in a person of her
peculiar nervous organisation, weakened as her body had been by long
illness, and her mind affected by what she regarded as her miraculous
recovery. As to the transudation of blood from the skin, Dr. Tuke, in
his 'Illustrations of the Influence of the Mind upon the Body in Health
and Disease' (p. 267), shows the phenomenon to be explicable naturally.
It is a well-authenticated fact, that under strong emotional excitement
blood escapes through the perspiratory ducts, apparently through the
rupture of the walls of the capillary passages of the skin.
We see, then, in Louise Lateau's case, how the mind affected by disease
may acquire faculties not possessed during health, and how in turn the
mind thus affected may influence the body so strangely as to suggest to
ignorant or foolish persons the operation of supernatural agencies.
The general conclusion to which we seem led by the observed
peculiarities in the mental faculties during disease is, that the
mind depends greatly on the state of the body for the co-ordination
of its various powers. In health, these are related in what may be
called the normal manner. Faculties capable of great development
under other conditions exist in moderate degree only, while probably,
either consciously or unconsciously, certain faculties are held in
control by others. But during illness, faculties not ordinarily used
suddenly or very rapidly acquire undue predominance, and controlling
faculties usually effective are greatly weakened. Then for a while
the mental capacity seems entirely changed. Powers supposed not to
exist at all (for of mental faculties, as of certain other qualities,
_de non existentibus et de non apparentibus eadem est ratio_) seem
suddenly created, as if by a miracle. Faculties ordinarily so strong
as to be considered characteristic seem suddenly destroyed, since they
no longer produce any perceptible effect. Or, as Brown-Sequard says,
summing up the results of a number of illustrative cases described in
a course of lectures delivered in Boston: 'It would seem that the mind
is largely dependent on physical conditions for the exercise of its
faculties, and that its strength and most remarkable powers, as well as
its apparent weakness, are often most clearly shown and recognised by
some inequality of action in periods of disturbed and greatly impaired
health.'
FOOTNOTES:
[Footnote 20: Since the above was written I have noticed a passage in
Dr. Carpenter's _Mental Physiology_, p. 719, bearing on the matter I
have been dealing with:--'The following statement recently made to me
by a gentleman of high intelligence, the editor of a most important
provincial newspaper, would be almost incredible, if cases somewhat
similar were not already familiar to us:--'I was formerly,' he said,
'a reporter in the House of Commons; and it several times happened
to me that, having fallen asleep from sheer fatigue towards the
end of a debate, I had found, on awaking after a short interval of
entire unconsciousness, that I had continued to note down correctly
the speaker's words.' 'I believe,' he added, 'that this is not an
uncommon experience among Parliamentary reporters.' The reading aloud
with correct emphasis and intonation, or the performance of a piece
of music, or (as in the case of Albert Smith) the recitation of a
frequently repeated composition, whilst the conscious mind is _entirely
engrossed_ in its own thoughts and feelings, may be thus accounted
for without the supposition that the mind is actively engaged in two
different operations at the same moment, which would seem tantamount to
saying that there are two egos in the same organism.' An instance in
my own experience seems even more remarkable than the reporter's work
during sleep, for he had but to continue a mechanical process, whereas
in my case there must have been thought. Late one evening at Cambridge
I began a game of chess with a fellow-student (now a clergyman, and
well known in chess circles). I was tired after a long day's rowing,
but continued the game to the best of my ability, until at a certain
stage I fell asleep, or rather fell into a waking dream. At any rate
all remembrance of what passed after that part of the game had entirely
escaped me when I awoke or returned to consciousness about three in
the morning. The chessboard was there, but the men were not as when
the last conscious move was made. The opponent's king was checkmated.
I supposed my opponent had set the men in this position either as a
joke or in trying over some end game. But I was assured that the game
had continued to the end, and that I had won, apparently playing as if
fully conscious! Of course I cannot certify this of my own knowledge.]
_DUAL CONSCIOUSNESS._
Rather more than two years ago I considered in the pages of 'Science
Byways' the theory originally propounded by Sir Henry Holland, but
then recently advocated by Dr. Brown-Sequard, of New York, that we
have two brains, each perfectly sufficient for the full performance
of mental functions. I did not for my own part either advocate or
oppose that theory, but simply considered the facts which had been
urged in support of it, or which then occurred to me as bearing upon
it, whether for or against. I showed, however, that some classes of
phenomena which had been quoted in support of the theory seemed in
reality opposed to it, when all the circumstances were considered. For
example, Brown-Sequard had referred to some of those well-known cases
in which during severe illness a language forgotten in the patient's
ordinary condition had been recalled, the recollection of the language
enduring only while the illness lasted. I pointed to a case in which
there had not been two mental conditions only, as indicated by the
language of the patient, but three; the person in question having in
the beginning of his illness spoken English only, in the middle of his
illness French only, and on the day of his death Italian only (the
language of his childhood). The interpretation of that case, and of
others of a similar kind, must, I remarked, be very different from that
which Brown-Sequard assigned, perhaps correctly, 'to cases of twofold
mental life.' A case of the last-named kind has recently been discussed
in scientific circles, which seems to me to bear very forcibly on the
question whether Holland's theory of a dual brain is correct. I propose
briefly to describe and examine this case, and some others belonging to
the same class, two of which were touched upon in my former essay, but
slightly only, as forming but a small part of the evidence dealt with
by Brown-Sequard, whose arguments I was then considering. I wish now to
deal, not with the question of the duality of the brain, but with the
more general question of dual or intermittent consciousness.
Among the cases dealt with by Brown-Sequard was that of a boy at
Notting Hill, who had two mental lives. Neither life presented
anything specially remarkable in itself. The boy was a well-mannered
lad in his abnormal as well as in his normal condition,--or one might
almost say (as will appear more clearly after other cases have been
considered) that the _two_ boys were quiet and well-behaved. But the
two mental lives were entirely distinct. In his normal condition the
boy remembered nothing which had happened in his abnormal condition;
and _vice versâ_, in his abnormal condition he remembered nothing which
had happened in his normal condition. He changed from either condition
to the other in the same manner. 'The head was seen to fall suddenly,
and his eyes closed, but he remained erect if standing at the time, or
if sitting he remained in that position (if talking, he stopped for a
while, and if moving, he stopped moving); and after a minute or two his
head rose, he started up, opened his eyes, and was wide awake again.'
While the head was drooped he appeared as if either sleeping or falling
asleep. He remained in the abnormal state for a period which varied
between one hour and three hours; it appears that every day, or nearly
every day, he fell once into his abnormal condition.
This case need not detain us long; but there are some points in it
which deserve more attention than they seem to have received from Dr.
Brown-Sequard. It is clear that if the normal and abnormal mental lives
of this boy had been entirely distinct, then in the abnormal condition
he would have been ignorant and--in those points in which manners
depend on training--ill-mannered. He would have known only, in this
condition, what he had learned in this condition; and as only about
a tenth part of his life was passed in the abnormal condition, and
presumably that portion of his life not usually selected as a suitable
time for teaching him, the abnormal boy would of necessity have been
much more backward in all things which the young are taught than the
normal boy. As nothing of this kind was noted, it would appear probable
that the boy's earlier years were common to both lives, and that his
unconsciousness of his ordinary life during the abnormal condition
extended only to those parts of his ordinary life which had passed
since these seizures began. Unfortunately, Brown-Sequard's account does
not mention when this had happened.
It does not appear that the dual brain theory is required so far
as this case is concerned. The phenomena seem rather to suggest a
peculiarity in the circulation of the brain corresponding in some
degree to the condition probably prevailing during somnambulism or
hypnotism, though with characteristic differences. It may at least
be said that no more valid reason exists for regarding this boy's
case as illustrating the distinctive duality of the brain than for so
regarding some of the more remarkable cases of somnambulism; for though
these differ in certain respects from the boy's case, they resemble
it in the circumstances on which Brown Sequard's argument is founded.
Speaking generally of hypnotism,--that is, of somnambulism artificially
produced,--Dr. Carpenter says, 'In hypnotism, as in ordinary
somnambulism, no remembrance whatever is preserved, in the waking
state, of anything that may have occurred during its continuance;
although the previous train of thought may be taken up and continued
uninterruptedly on the next occasion when hypnotism is induced.' In
these respects the phenomena of hypnotism precisely resemble those of
dual consciousness as observed in the boy's case. In what follows, we
observe features of divergence. Thus 'when the mind is not excited
to activity by the stimulus of external impressions, the hypnotised
subject appears to be profoundly asleep; a state of complete torpor,
in fact, being usually the first result of the process just described,
and any subsequent manifestation of activity being procurable only by
the prompting of the operator. The hypnotised subject, too, rarely
opens his eyes; his bodily movements are usually slow; his mental
operations require a considerable time for their performance; and there
is altogether an appearance of heaviness about him which contrasts
strongly with the comparatively wide-awake air of him who has not
passed beyond the ordinary biological state.'
It would not be easy to find an exact parallel to the case of the
two-lived boy in any recorded instance of somnambulism. In fact, it
is to be remembered that recorded instances of mental phenomena are
all selected for the very reason that they are exceptional, so that it
would be unreasonable to expect them closely to resemble each other.
One case, however, may be cited, which in certain points resembles the
case of Dr. Brown-Sequard's patient. It occurred within Dr. Carpenter's
own experience. A young lady of highly nervous temperament suffered
from a long and severe illness, characterised by all the most marked
forms of hysterical disorder. In the course of this illness came a
time when she had a succession of somnambulistic seizures. 'The state
of somnambulism usually supervened in this case in the waking state,
instead of arising, as it more commonly does, out of the conditions
of ordinary sleep. In this condition her ideas were at first entirely
fixed upon one subject--the death of her only brother, which had
occurred some years previously. To this brother she had been very
strongly attached; she had nursed him in his last illness; and it was
perhaps the return of the anniversary of his death, about the time
when the somnambulism first occurred, that gave to her thoughts that
particular direction. She talked constantly of him, retraced all the
circumstances of his illness, and was unconscious of anything that was
said to her which had not reference to this subject.... Although her
eyes were open, she recognised no one in this state,--not even her own
sister, who, it should be mentioned, had not been at home at the time
of her brother's last illness.' (It will presently appear, however,
that she was able to recognise those who were about her during these
attacks, since she retained ill-feeling against one of them; moreover,
the sentences which immediately follow suggest that the sense of sight
was not dormant.) 'It happened on one occasion, that when she passed
into this condition, her sister, who was present, was wearing a locket
containing some of their deceased brother's hair. As soon as she
perceived this locket she made a violent snatch at it, and would not
be satisfied until she had got it into her possession, when she began
to talk to it in the most endearing and even extravagant terms. Her
feelings were so strongly excited on this subject, that it was deemed
prudent to check them; and as she was inaccessible to all entreaties
for the relinquishment of the locket, force was employed to obtain
it from her. She was so determined, however, not to give it up, and
was so angry at the gentle violence used, that it was found necessary
to abandon the attempt, and having become calmer after a time, she
passed off into ordinary sleep. Before going to sleep, however, she
placed the locket under her pillow, remarking, "Now I have hid it
safely, and they shall not take it from me." On awaking in the morning
she had not the slightest consciousness of what had passed; but the
impression of the excited feelings still remained, for she remarked to
her sister, 'I cannot tell what it is that makes me feel so, but every
time that S. comes near me I have a kind of shuddering sensation;'
the individual named being a servant, whose constant attention to her
had given rise to a feeling of strong attachment on the side of the
invalid, but who had been the chief actor in the scene of the previous
evening. This feeling wore off in the course of a day or two. A few
days afterwards the somnambulism again returned; and the patient being
upon her bed at the time, immediately began to search for the locket
under her pillow.' As it had been removed in the interval, 'she was
unable to find it, at which she expressed great disappointment, and
continued searching for it, with the remark, "It _must_ be there--I
put it there myself a few minutes ago, and no one can have taken it
away." In this state the presence of S. renewed her previous feelings
of anger; and it was only by sending S. out of the room that she could
be calmed and induced to sleep. The patient was the subject of many
subsequent attacks, in every one of which the anger against S. revived,
until the current of thought changed, no longer running exclusively
upon what related to her brother, but becoming capable of direction
by _suggestions_ of various kinds presented to her mind, either in
conversation, or, more directly, through the several organs of sense.'
I have been particular in quoting the above account, because it appears
to me to illustrate well, not only the relation between the phenomena
of dual consciousness and somnambulism, but the dependence of either
class of phenomena on the physical condition. If it should appear that
dual consciousness is invariably associated with some disorder either
of the nervous system or of the circulation, it would be impossible,
or at least very difficult, to maintain Brown-Sequard's explanation of
the boy's case. For one can hardly imagine it possible that a disorder
of the sort should be localised so far as the brain is concerned, while
in other respects affecting the body generally. It so chances that the
remarkable case recently dealt with by French men of science forms a
sort of connecting link between the boy's case and the case just cited.
It closely resembles the former in certain characteristic features,
while it resembles the latter in the evidence which it affords of
the influence of the physical condition on the phenomena of double
consciousness. The original narrative by M. Azam is exceedingly prolix;
but it has been skilfully condensed by Mr. H.J. Slack, in the pages of
a quarterly journal of science. I follow his version in the main.
The subject of the disorder, Felida X., was born in Bordeaux in 1843.
Until the age of thirteen she differed in no respect from other
girls. But about that time symptoms of hysterical disorder presented
themselves, and although she was free from lung-disease, she was
troubled with frequent spitting of blood. After this had continued
about a year, she for the first time manifested the phenomena of
double consciousness. Sharp pains attacked both temples, and in a
few moments she became unconscious. This lasted ten minutes, after
which she opened her eyes, and entered into what M. Azam calls her
second state, in which she remained for an hour or two, after which
the pains and unconsciousness came on again, and she returned to her
ordinary condition. At intervals of about five or six days, such
attacks were repeated; and her relations noticed that her character
and conduct during her abnormal state were changed. Finding also that
in her usual condition she remembered nothing which had passed when
she was in the other state, they thought she was becoming idiotic;
and presently called in M. Azam, who was connected with a lunatic
asylum. Fortunately, he was not so enthusiastic a student of mental
aberration as to recognise a case for the lunatic asylum in every
instance of phenomenal mental action. He found Felida intelligent, but
melancholy, morose, and taciturn, very industrious, and with a strong
will. She was very anxious about her bodily health. At this time the
mental changes occurred more frequently than before. Nearly every day,
as she sat with her work on her knees, a violent pain shot suddenly
through her temples, her head dropped upon her breast, her arms fell
by her side, and she passed into a sort of sleep, from which neither
noises, pinches, nor pricks could awaken her. This condition lasted
now only two or three minutes. 'She woke up in quite another state,
smiling gaily, speaking briskly, and trilling (_fredonnant_) over her
work, which she recommenced at the point where she left it. She would
get up, walk actively, and scarcely complained of any of the pains
she had suffered from so severely a few minutes before. She busied
herself about the house, paid calls, and behaved like a healthy young
girl of her age. In this state she remembered perfectly all that had
happened in her two conditions.' (In this respect her case is distinct
from both the former, and is quite exceptional. In fact, the inclusion
of the consciousness of both conditions during the continuance of one
condition only, renders her case not, strictly speaking, one of double
consciousness, the two conditions not being perfectly distinct from
each other.) 'In this second life, as in the other, her moral and
intellectual faculties, though different, were incontestably sound.
After a time (which in 1858 lasted three or four hours), her gaiety
disappeared, the torpor suddenly ensued, and in two or three minutes
she opened her eyes and re-entered her ordinary life, resuming any work
she was engaged in just where she left off. In this state she bemoaned
her condition, and was quite unconscious of what had passed in the
previous state. If asked to continue a ballad she had been singing, she
knew nothing about it, and if she had received a visitor, she believed
she had seen no one. The forgetfulness extended to everything which
happened during her second state, and not to any ideas or information
acquired before her illness.' Thus her early life was held in
remembrance during both her conditions, her consciousness in these two
conditions being in this respect single; in her second or less usual
condition she remembered also all the events of her life, including
what had passed since these seizures began; and it was only in her
more usual condition that a portion of her life was lost to her--that,
namely, which had passed during her second condition. In 1858 a new
phenomenon was noticed as occasionally occurring--she would sometimes
wake from her second condition in a fit of terror, recognising no one
but her husband. The terror did not last long, however; and during
sixteen years of her married life, her husband only noticed this terror
on thirty occasions.
A painful circumstance preceding her marriage somewhat forcibly
exhibited the distinction between her two states of consciousness.
Rigid in morality during her usual condition, she was shocked by the
insults of a brutal neighbour, who told her of a confession made to
M. Azam during her second condition, and accused her of shamming
innocence. The attack--unfortunately, but too well founded as far as
facts were concerned--brought on violent convulsions, which required
medical attendance during two or three hours. It is important to
notice the difference thus indicated between the character of the
personalities corresponding to her two conditions. 'Her moral
faculties,' says M. Azam, 'were incontestably sound in her second life,
though different,'--by which, be it understood, he means simply that
her sense of right and wrong was just during her second condition,
not, of course, that her conduct was irreproachable. She was in this
condition, as in the other, altogether responsible for her actions.
But her power of self-control, or rather perhaps the relative power of
her will as compared with tendencies to wrong-doing, was manifestly
weaker during her second condition. In fact, in one condition she
was oppressed and saddened by pain and anxiety, whereas in the other
she was almost free from pain, gay, light-hearted, and hopeful. Now
I cannot altogether agree with Mr. Slack's remark, that if, during
her second state, 'she had committed a robbery or an assassination,
no moral responsibility could have been assumed to rest upon her with
any certainty, by any one acquainted with her history,' for her moral
faculties in her second condition being incontestably sound, she was
clearly responsible for her actions while in that condition. But
certainly, the question of punishment for such an offence would be not
a little complicated by her twofold personality. To the woman in her
ordinary condition, remembering nothing of the crime committed (on the
supposition we are dealing with), in her abnormal condition, punishment
for that crime would certainly seem unjust, seeing that her liability
to enter into that condition had not in any degree depended on her own
will. The drunkard who, waking in the morning with no recollection
of the events of the past night, finds himself in gaol for some crime
committed during that time, although he may think the punishment he has
to endure severe measure for a crime of which in his ordinary condition
he is incapable, knows at least that he is responsible for placing
himself under that influence which made the crime possible. Supposing
even he had not had sufficient experience of his own character when
under the influence of liquor, to have reason to fear he might be
guilty of the offence, he yet perceives that to make intoxication
under any circumstances an excuse for crime would be most dangerous
to the community, and that he suffers punishment justly. But the case
of dual consciousness is altogether different, and certainly where
responsibility exists under both conditions, while yet impulse and the
restraining power of will are differently related in one and the other
condition, the problem of satisfying justice is a most perplexing one.
Here are in effect two different persons residing in one body, and it
is impossible to punish one without punishing the other also. Supposing
justice waited until the abnormal condition was resumed, then the
offender would probably recognise the justice of punishment; but if the
effects of the punishment continued until the usual condition returned,
a person would suffer who was conscious of no crime. If the offence
were murder, and if capital punishment were inflicted, the ordinary
individuality, innocent entirely of murder, would be extinguished along
with the first, a manifest injustice. As Huxley says of a similar case,
'the problem of responsibility is here as complicated as that of the
prince-bishop, who swore as a prince and not as a bishop. 'But, your
highness, if the prince is damned, what will become of the bishop?'
said the peasant.'[21]
It does not appear to me that there is in the case of Felida X. any
valid reason for regarding the theory of two brains as the only
available explanation. It is a noteworthy circumstance, that the pains
preceding each change of condition affected both sides of the head.
Some modification of the circulation seems suggested as the true
explanation of the changes in condition, though the precise nature
of such modification, or how it may have been brought about, would
probably be very difficult to determine. The state of health, however,
on which the attacks depended seems to have affected the whole body of
the patient, and the case presents no features suggesting any lateral
localisation of the cerebral changes.
On the other hand, the case of Sergeant F. (a few of the circumstances
of which were mentioned in my essay entitled 'Have we two Brains?'),
seems to correspond with Dr. Holland's theory, though that theory is
far from explaining all the circumstances. The man was wounded by
a bullet which fractured his _left_ parietal bone, and his _right_
arm and leg were almost immediately paralysed. When he recovered
consciousness three weeks later, the _right_ side of the body was
completely paralysed, and remained so for a year. These circumstances
indicate that the cause of the mischief still existing lay in the shock
which the left side of the brain received when the man was wounded.
The right side may have learned (as it were) to exercise the functions
formerly belonging to the left side, and thus the paralysis affecting
the right side until this had happened may have passed away. These
points are discussed in the essay above named, however, and need not
here detain us. Others which were not then dealt with may now be
noted with advantage. We would specially note some which render it
doubtful whether in the abnormal condition the man's brain acts at all,
whether in fact his condition, so far as consciousness was concerned,
is not similar to that of a frog deprived of its brain in a certain
well-known experiment. (This appears to be the opinion to which
Professor Huxley inclines, though, with proper scientific caution, he
seems disposed to suspend his judgment.) The facts are very singular,
whatever the explanation may be.
In the normal condition, the man is what he was before he was
wounded--an intelligent, kindly fellow, performing satisfactorily the
duties of a hospital attendant. The abnormal state is ushered in by
pains in the forehead, as if caused by the constriction of a band of
iron. In this state the eyes are open and the pupils dilated. (The
reader will remember Charles Reade's description of David Dodd's eyes,
'like those of a seal.') The eyeballs work incessantly, and the jaws
maintain a chewing motion. If the man is _en pays de connaissance_,
he walks about as usual; but in a new place, or if obstacles are set
in his way, he stumbles, feels about with his hands, and so finds his
way. He offers no resistance to any forces which may act upon him,
and shows no signs of pain if pins are thrust into his body by kindly
experimenters. No noise affects him. He eats and drinks apparently
without tasting or smelling his food, accepting assafoetida or vinegar
as readily as the finest claret. He is sensible to light only under
certain conditions. But the sense of touch is strangely exalted (in
all respects apparently except as to sensations of pain or pleasure),
taking in fact the place of all the other senses. I say the sense of
touch, but it is not clear whether there is any real sensation at all.
The man appears in the abnormal condition to be a mere machine. This
is strikingly exemplified in the following case, which I translate
directly from Dr. Mesnet's account:--'He was walking in the garden
under a group of trees, and his stick, which he had dropped a few
minutes before, was placed in his hands. He feels it, moves his hand
several times along the bent handle of the stick, becomes watchful,
seems to listen, suddenly he calls out, "Henry!" then, "There they are!
there are at least a score of them! join us two, we shall manage it."
And then putting his hand behind his back as if to take a cartridge,
he goes through the movement of loading his weapon, lays himself
flat on the grass, his head concealed by a tree, in the posture of a
sharpshooter, and with shouldered weapon follows all the movements of
the enemy whom he fancies he sees at a short distance.' This, however,
is an assumption: the man cannot in this state _fancy_ he sees, unless
he has at least a recollection of the sensation of sight, and this
would imply cerebral activity. Huxley, more cautious, says justly
that the question arises 'whether the series of actions constituting
this singular pantomime was accompanied by the ordinary states of
consciousness or not? Did the man dream that he was skirmishing? or was
he in the condition of one of Vaucanson's automata--a mechanism worked
by molecular changes in his nervous system? The analogy of the frog
shows that the latter assumption is perfectly justifiable.'
The pantomimic actions just related corresponded to what probably
happened a few moments before the man was wounded; but this human
automaton (so to call him, without theorising as to his actual
condition) goes through other performances. He has a good voice, and
was at one time a singer in a _café_. 'In one of his abnormal states he
was observed to begin humming a tune. He then went to his room, dressed
himself carefully, and took up some parts of a periodical novel which
lay on his bed, as if he were trying to find something. Dr. Mesnet,
suspecting that he was seeking his music, made up one of these into a
roll and put it into his hand. He appeared satisfied, took up his cane
and went downstairs to the door. Here Dr. Mesnet, turned him round, and
he walked quite contentedly in the opposite direction, towards the room
of the _concierge_. The light of the sun shining through a window now
happened to fall upon him, and seemed to suggest the footlights of the
stage on which he was accustomed to make his appearance. He stopped,
opened his roll of imaginary music, put himself into the attitude of a
singer, and sung, with perfect execution, three songs, one after the
other. After which he wiped his face with his handkerchief and drank,
without a grimace, a tumbler of strong vinegar and water which was put
into his hand.'
But the most remarkable part of the whole story is that which follows.
'Sitting at a table in one of his abnormal states, Sergeant F. took
up a pen, felt for paper and ink, and began to write a letter to his
general, in which he recommended himself for a medal on account of
his good conduct and courage.' (Rather a strange thing, by the way,
for a mere automaton to do.) 'It occurred to Dr. Mesnet to ascertain
experimentally how far vision was concerned in this act of writing. He
therefore interposed a screen between the man's eyes and his hands;
under these circumstances, F. went on writing for a short time, but the
words became illegible, and he finally stopped, without manifesting
any discontent. On the withdrawal of the screen, he began to write
again where he had left off. The substitution of water for ink in the
inkstand had a similar result. He stopped, looked at his pen, wiped it
on his coat, dipped it in the water, and began again with a similar
result. On another occasion, he began to write upon the topmost of
ten superimposed sheets of paper. After he had written a line or two,
this sheet was suddenly drawn away. There was a slight expression of
surprise, but he continued his letter on the second sheet exactly as if
it had been the first. This operation was repeated five times, so that
the fifth sheet contained nothing but the writer's signature at the
bottom of the page. Nevertheless, when the signature was finished, his
eyes turned to the top of the blank sheet, and he went through the form
of reading what he had written--a movement of the lips accompanying
each word; moreover, with his pen, he put in such corrections as were
needed, in that part of the blank page which corresponded with the
position of the words which required correction in the sheets which had
been taken away. If the five sheets had been transparent, therefore,
they would, when superposed, have formed a properly written and
corrected letter. Immediately after he had written his letter, F. got
up, walked down to the garden, made himself a cigarette, lighted and
smoked it. He was about to prepare another, but sought in vain for his
tobacco-pouch, which had been purposely taken away. The pouch was now
thrust before his eyes and put under his nose, but he neither saw nor
smelt it; when, however, it was placed in his hand, he at once seized
it, made a fresh cigarette, and ignited a match to light the latter.
The match was blown out, and another lighted match placed close before
his eyes, but he made no attempt to take it; and if his cigarette was
lighted for him, he made no attempt to smoke. All this time his eyes
were vacant, and neither winked nor exhibited any contraction of the
pupil.'
These and other similar experiments are explained by Dr. Mesnet (and
Professor Huxley appears to agree with him) by the theory that F. 'sees
some things and not others; that the sense of sight is accessible to
all things which are brought into relation with him by the sense of
touch, and, on the contrary, insensible to all things which lie outside
this relation.' It seems to me that the evidence scarcely supports
this conclusion. In every case where F. appears to see, it is quite
possible that in reality he is guided entirely by the sense of touch.
All the circumstances accord much better with this explanation than
with the theory that the sense of sight was in any way affected. Thus
the sunlight shining through the window must have affected the sense of
touch, and in a manner similar to what F. had experienced when before
the footlights of the stage, where he was accustomed to appear as a
singer. In this respect there was a much closer resemblance between
the effect of sunlight and that of the light from footlights, than in
the circumstances under which both sources of light affect the sense
of sight. For in one case the light came from above, in the other from
below; the heat would in neither case be sensibly localised. Again,
when a screen was interposed between his eyes and the paper on which
he was writing, he probably became conscious of its presence in the
same way that a blind man is conscious of the presence of objects near
him, even (in some cases) of objects quite remote, by some subtle
effects discernible by the sense of touch excited to abnormal relative
activity in the absence of impressions derived from the sense of
sight. It is true that one might have expected him to continue writing
legibly, notwithstanding the interposed screen; but the consciousness
of the existence of what in his normal condition would effectually
have prevented his writing legibly, would be sufficient to explain
his failure. If, while in full possession of all our senses, the
expectation of failure quite commonly causes failure, how much more
likely would this be to happen to a man in F.'s unfortunate abnormal
condition. The sense of touch again would suffice to indicate the
presence of water instead of ink in his pen when he was writing. I
question whether the difference might not be recognised by any person
of sensitive touch after a little practice; but certainly a blind
man, whose sense of touch was abnormally developed, would recognise
the difference, as we know from experiments which have indicated even
greater delicacy of perception than would be required for this purpose.
The experiment with superposed sheets of paper is more remarkable than
any of the others, but certainly does not suggest that light makes
any impression upon Sergeant F. It proves, in fact, so far as any
experiment could prove such a point, that the sense of touch alone
regulates the man's movements. Unconscious of any change (because,
after the momentary surprise produced by the withdrawal of the paper,
he still found he had paper to write on), he continued writing. He
certainly did not in this case, as Dr. Mesnet suggests, see all things
which are brought into relation with him by the sense of touch; for if
he had, he would not have continued to write when he found the words
already written no longer discernible.
On the whole, it appears reasonable to conclude, as Professor Huxley
does, that though F. may be conscious in his abnormal state, he may
also be a mere automaton for the time being. The only circumstance
which seems to oppose itself very markedly to the latter view is the
letter-writing. Everything else that this man did was what he had
already done prior to the accident. If it could be shown that the
letters written in his abnormal state were transcripts, not merely
_verbatim et literatim_, but exact in every point, of some which he
had written before he was wounded, then a strong case would be made
out for the automaton theory. Certainly, few instances have come under
the experience of scientific men where a human being has so closely
resembled a mere machine as this man appears to do in his abnormal
condition.
The moral nature of F. in his abnormal condition is for this reason
a matter of less interest than it would be, did he show more of the
semblance of conscious humanity. Still it is worthy of notice, that,
whereas in his normal condition he is a perfectly honest man, in
his abnormal state 'he is an inveterate thief, stealing and hiding
away whatever he can lay hands on with much dexterity, and with an
absolutely absurd indifference as to whether the property is his own or
not.'
It will be observed that the cases of dual consciousness thus far
considered, though alike in some respects, present characteristic
divergences. In that of the boy at Norwood, the two characters were
very similar, so far as can be judged, and each life was distinct
from the other. The next case was only introduced to illustrate the
resemblance in certain respects between the phenomena of somnambulism
and those of double or rather alternating consciousness. The woman
Felida X. changed markedly in character when she passed from one state
to the other. Her case was also distinguished from that of the boy by
the circumstance that in one state she was conscious of what had passed
in the other, but while in this other state was unconscious of what
had passed in the former. Lastly, in Sergeant F.'s case we have to
deal with the effect of an injury to the brain, and find a much greater
difference between the two conditions than in the other cases. Not only
does the man change in character, but it may justly be said that he is
little more than an animal, even if he can be regarded as more than a
mere automaton while in the abnormal condition. We find that a similar
variety characterises other stories of double consciousness. Not only
are no two cases closely alike, but no case has been noted which has
not been distinguished by some very marked feature from all others.
Thus, although in certain respects the case we have next to consider
resembles very significantly the case of Sergeant F., it also has a
special significance of its own, and may help us to interpret the
general problem presented to us by the phenomena of dual consciousness.
I abridge, and in some respects simplify, the account given by Dr.
Carpenter in his interesting treatise on _Mental Physiology_. Comments
of my own are distinguished from the abridged narrative by being placed
within brackets:--
A young woman of robust constitution had narrowly escaped drowning.
She was insensible for six hours, and continued unwell after being
restored to animation. Ten days later she was seized with a fit of
complete stupor, which lasted four hours; when she opened her eyes she
seemed to recognise no one, and appeared to be utterly deprived of
the senses of hearing, taste, and smell, as well as of the power of
speech. Sight and touch remained, but though movements were excited
and controlled by these senses, they seemed to arouse no ideas in her
mind. In fact, her mental faculties seemed entirely suspended. Her
vision at short distances was quick, and the least touch startled her;
but unless she was touched or an object were placed where she could not
help seeing it, she took no notice of what was passing around her. [It
does not appear to me certain that at this stage of her illness she
_saw_ in the ordinary sense of the word; the sense of touch may alone
have been affected, as it certainly is affected to some degree by any
object so placed that _it could not but be seen by a short-sighted
person_. But it is clear that later the sense of sight was restored,
supposing, which is not perhaps probable, that it was ever lost in
the early stage.] She did not even know her own mother, who attended
constantly upon her. Wherever she was placed she remained. Her appetite
was good, but [like F.] she ate indifferently whatever she was fed
with, and took nauseous medicines as readily as agreeable food. Her
movements were solely of the automatic kind. Thus, she swallowed food
put into her mouth, but made no effort to feed herself. Yet when her
mother had conveyed the spoon [in the patient's hand] a few times to
her mouth, the patient continued the operation. It was necessary,
however, to repeat this lesson every time she was fed, showing the
complete absence of memory. 'The very limited nature of her faculties,
and the automatic life she was leading, appear further evident from the
following particulars. One of her first acts on recovering from the
fit had been to busy herself in picking the bedclothes; and as soon
as she was able to sit up and be dressed, she continued the habit by
incessantly picking some portion of her dress. She seemed to want an
occupation for her fingers, and accordingly part of an old straw bonnet
was given to her, which she pulled into pieces with great minuteness;
she was afterwards bountifully supplied with roses: she picked off the
leaves, and then tore them up into the smallest particles imaginable.
A few days subsequently, she began forming upon the table, out of
those minute particles, rude figures of roses, and other common garden
flowers; she had never received any instructions in drawing. Roses
not being so plentiful in London, waste paper and a pair of scissors
were put into her hand, and for some days she found an occupation in
cutting the paper into shreds; after a time these cuttings assumed rude
shapes and figures, and more particularly the shapes used in patchwork.
At length she was supplied with proper materials for patchwork, and
after some initiatory instruction, she took to her needle and to this
employment in good earnest. She now laboured incessantly at patchwork
from morning till night, and on Sundays and week-days, for she knew no
difference of days; nor could she be made to comprehend the difference.
She had no remembrance from day to day of what she had been doing on
the previous day, and so every morning commenced _de novo_. Whatever
she began, that she continued to work at while daylight lasted;
manifesting no uneasiness for anything to eat or drink, taking not the
slightest heed of anything which was going on around her, but intent
only on her patchwork.' From this time she began to improve, learning
like a child to register ideas. She presently learned worsted-work,
and showed delight in the harmony of colours and considerable taste in
selecting between good and bad patterns. After a while she began to
devise patterns of her own. But she still had no memory from day to day
of what she had done, and unless the unfinished work of one day was set
before her on the next, she would begin something new.
And now, for the first time, ideas derived from her life before her
illness seemed to be awakened within her. When pictures of flowers,
trees, and animals were shown her, she was pleased; but when she
was shown a landscape in which there was a river or a troubled sea,
she became violently agitated, and a fit of spasmodic rigidity and
insensibility immediately followed. The mere sight of water in motion
made her shudder. Again, from an early stage of her illness she had
derived pleasure from the proximity of a young man to whom she had been
attached. At a time when she did not remember from one hour to another
what she was doing, she would anxiously await his evening visit, and
be fretful if he failed to pay it. When, during her removal to the
country, she lost sight of him, she became unhappy and suffered from
frequent fits; on the other hand, when he remained constantly near her,
she improved in health, and early associations were gradually awakened.
At length a day came when she uttered her first word in this her second
life. She had learned to take heed of objects and persons around her;
and on one occasion, seeing her mother excessively agitated, she became
excited herself, and suddenly, yet hesitatingly, exclaimed, 'What's the
matter?' After this she began to articulate a few words. For a time she
called every object and person 'this,' then gave their right names to
wild flowers (of which she had been passionately fond when a child),
and this 'at a time when she exhibited not the least recollection of
the "old familiar friends and places" of her childhood.' The gradual
expansion of her intellect was manifested chiefly at this time in signs
of emotional excitement, frequently followed by attacks of spasmodic
rigidity and insensibility.
It was through the emotions that the patient was restored to the
consciousness of her former self. She became aware that her lover
was paying attention to another woman, and the emotion of jealousy
was so strongly excited, that she had a fit of insensibility which
resembled her first attack in duration and severity. But it restored
her to herself. 'When the insensibility passed off, she was no longer
spell-bound. The veil of oblivion was withdrawn; and, as if awakening
from a sleep of twelve months' duration, she found herself surrounded
by her grandfather, grandmother, and their familiar friends and
acquaintances. She awoke in the possession of her natural faculties and
former knowledge; but without the slightest remembrance of anything
which had taken place in the year's interval, from the invasion of
the first fit to the [then] present time. She spoke, but she heard
not; she was still deaf, but being able to read and write as formerly,
she was no longer cut off from communication with others. From this
time she rapidly improved, but for some time continued deaf. She soon
perfectly understood by the motion of her lips what her mother said;
they conversed with facility and quickness together, but she did not
understand the language of the lips of a stranger. She was completely
unaware of the change in her lover's affections which had taken
place in her state of second consciousness; and a painful explanation
was necessary. This, however, she bore very well; and she has since
recovered her previous bodily and mental health.
There is little in this interesting narrative to suggest that the
duality of consciousness in this case was in any way dependent on the
duality of the brain. During the patient's abnormal condition, the
functions of the brain [proper] would seem to have been for a time
in complete abeyance, and then to have been gradually restored. One
can perceive no reason for supposing that the shock she had sustained
would affect one side rather than the other side of the brain, nor why
her recovery should restore one side to activity and cause the side
which (on the dual brain hypothesis) had been active during her second
condition to resume its original activity. The phenomena appear to
suggest that in some way the molecular arrangement of the brain matter
became modified during her second condition; and that when the original
arrangement was restored all recognisable traces of impressions
received while the abnormal arrangement lasted were obliterated. As Mr.
Slack presents one form of this idea, 'the grey matter of the brain may
have its molecules arranged in patterns somewhat analogous to those
of steel filings under the influence of a magnet, but in some way the
direction of the forces--or vibrations--may be changed in them. The
pattern will then be different.' We know certainly that thought and
sensation depend on material processes,--chemical reactions between
the blood and the muscular tissues. Without the free circulation of
blood in the brain, there can be neither clear thought nor ready
sensation. With changes in the nature of the circulation come changes
in the quality of thought and the nature of sensation, and with them
the emotions are changed also. Such changes affect all of us to some
degree. It may well be that such cases as we have been dealing with are
simply instances of the exaggerated operation of causes with which we
are all familiar; and it may also be that in the exaggeration itself
of these causes of change lies the explanation of the characteristic
peculiarity of cases of dual consciousness,--the circumstances, namely,
that either the two states of consciousness are absolutely distinct
one from the other, or that in one state only are events remembered
which happened in the other, no recollection whatever remaining in this
latter state of what happened in the other, or, lastly, that only faint
impressions excited by some intense emotion experienced in one state
remain in the other state.
It seems possible, also, that some cases of another kind may find
their explanation in this direction, as, for instance, cases in which,
through some strange sympathy, the brain of one person so responds to
the thoughts of another that for the time being the personality of the
person thus influenced may be regarded as in effect changed into that
of the person producing the influence. Thus, in one singular case cited
by Dr. Carpenter, a lady was 'metamorphosed into the worthy clergyman
on whose ministry she attended, and with whom she was personally
intimate. I shall never forget,' he says, 'the intensity of the
lackadaisical tone in which she replied to the matrimonial counsels of
the physician to whom he (she) had been led to give a long detail of
his (her) hypochondriacal symptoms: "A wife for a dying man, doctor."
No _intentional_ simulation could have approached the exactness of the
imitation alike in tone, manners, and language, which spontaneously
proceeded from the idea with which the fair subject was possessed,
that she herself experienced all the discomforts whose detail she had
doubtless frequently heard from the real sufferer.' The same lady, at
Dr. Carpenter's request, mentally 'ascended in a balloon and proceded
to the North Pole in search of Sir John Franklin, whom she found alive,
and her description of his appearance and that of his companions was
given with an inimitable expression of sorrow and pity.'
It appears to us that very great interest attaches to the researches
made by Prof. Barrett into cases of this kind, and that it is in
this direction we are to look for the explanation of many mysterious
phenomena formerly regarded as supernatural, but probably all
admitting (at least all that have been properly authenticated) of
being interpreted so soon as the circumstances on which consciousness
depends shall have been determined. Thus the following account of
experiments made at the village school in Westmeath seem especially
suggestive: 'Selecting some of the village children, and placing them
in a quiet room, giving each some small object to look at steadily,
he found one amongst the number who readily passed into a state of
reverie. In that state the subject could be made to believe the most
extravagant statements, such as that the table was a mountain, a
chair a pony, a mark on the floor, an insuperable obstacle. The girl
thus mesmerised passed on the second occasion into a state of deeper
sleep or trance, wherein no sensation whatever was experienced, unless
accompanied by pressure on the eyebrows of the subject. When the
pressure of the fingers was removed, the girl fell back in her chair
utterly unconscious of all around, and had lost all control over her
voluntary muscles. On reapplying the pressure, though her eyes remained
closed, she sat up and answered questions readily, but the manner in
which she answered them, her acts and expressions, were capable of
wonderful diversity, by merely altering the place on the head where the
pressure was applied. So sudden and marked were the changes produced
by a movement of the fingers, that the operation seemed very like
playing on some musical instrument. On a third occasion the subject,
after passing through these, which have been termed the biological
and phrenological states, became at length keenly and wonderfully
sensitive to the voice and acts of the operator. It was impossible for
the latter to call the girl by her name, however faintly and inaudibly
to those around, without at once eliciting a prompt response. If the
operator tasted, smelt, or touched anything, or experienced any sudden
sensation of warmth or cold, a corresponding effect was produced on
the subject, though nothing was said, nor could the subject have seen
what had occurred to the operator. To be assured of this he bandaged
the girl's eyes with great care, and the operator having gone behind
the girl to the other end of the room, he watched him and the girl, and
repeatedly assured himself of this fact.' Thus far, Professor Barrett's
observations, depending in part on what the operator experienced, may
be open to just so much doubt as may affect our opinion of the veracity
of a person unknown; but in what follows we have his own experience
alone to consider. 'Having mesmerised the girl himself, he took a card
at random from a pack which was in a drawer in another room. Glancing
at the card to see what it was, he placed it within a book, and in that
state brought it to the girl. Giving her the closed book, he asked
her to tell him what he had put within its leaves. She held the book
close to the side of her head, and said, 'I see something inside with
red spots on it; and she afterwards said there were five red spots on
it. The card was the five of diamonds. The same result occurred with
another card; and when an Irish bank-note was substituted for the card,
she said, 'Oh, now I see a number of heads--so many that I cannot
count them.' He found that she sometimes failed to guess correctly,
asserting that the things were dim; and she could give no information
of what was within the book unless he had previously known what it
was himself. More remarkable still, he asked her to go in imagination
to Regent Street, in London, and tell him what shops she had seen.
The girl had never been out of her remote village, but she correctly
described to him Mr. Ladd's shop, of which he happened to be thinking,
and mentioned the large clock that overhangs the entrance to Beak
Street. In many other cases he convinced himself that the existence of
a distinct idea in his own mind gave rise to an image of the idea (that
is, to a corresponding image) on the mind of the subject; not always
a clear image, but one that could not fail to be recognised as a more
or less distorted reflection of his own thought.' It is important to
notice the limit which a scientific observer thus recognised in the
range of the subjects' perception. It has been stated that subjects
in this condition have been able to describe occurrences not known to
any person, which yet have been subsequently verified. Although some
narratives of the kind have come from persons not likely to relate
what they _knew_ to be untrue, the possibility of error outweighs the
probability that such narratives can really be true. There is a form
of unconscious cerebration by which untruthful narratives come to be
concocted in the mind. For instance, Dr. Carpenter heard a scrupulously
conscientious lady asseverate that a table 'rapped' when nobody was
within a yard of it; but the story was disproved by the lady herself,
who found from her note-book, recording what really took place, that
the hands of six persons rested on the table when it rapped. And apart
from the unconscious fiction-producing power of the mind, there is
always the possibility, nay, often the extreme probability, that the
facts of a case may be misunderstood. Persons may be supposed to know
nothing about an event who have been conscious of its every detail;
nay, a person may himself be unconscious of his having known, and in
fact of his really knowing, of a particular event. Dual consciousness
in this particular sense is a quite common experience, as, for
instance, when a story is told us which we receive at first as new,
until gradually the recollection dawns upon us and becomes momentarily
clearer and clearer, not only that we have heard it before, but of the
circumstances under which we heard it, and even of details which the
narrator from whom a few moments before we receive it as a new story
has omitted to mention.[22]
The most important of all the questions depending on dual consciousness
is one into which I could not properly enter at any length in these
pages--the question, namely, of the relation between the condition of
the brain and responsibility, whether such responsibility be considered
with reference to human laws or to a higher and all-knowing tribunal.
But there are some points not wanting in interest which may be here
more properly considered.
In the first place it is to be noticed that a person who has passed
into a state of abnormal consciousness, or who is in the habit of doing
so, can have no knowledge of the fact in his normal condition except
from the information of others. The boy at Norwood might be told of
what he had said and done while in his less usual condition, but so
far as any experience of his own was concerned, he might during all
that time have been in a profound sleep. Similarly of all the other
cases. So that we have here the singular circumstance to consider, that
a person may have to depend on the information of others respecting
his own behaviour--not during sleep or mental aberration or ordinary
absence of mind--but (in some cases at least) while in possession of
all his faculties and unquestionably responsible for his actions. Not
only might a person find himself thus held responsible for actions
of which he had no knowledge, and perhaps undeservedly blamed or
condemned, but he might find himself regarded as untruthful because of
his perfectly honest denial of all knowledge of the conduct attributed
to him. If such cases were common, again, it would not improbably
happen that the simulation of dual consciousness would become a
frequent means of attempting to evade responsibility.
Another curious point to be noticed is this. Supposing one subject
to alternations of consciousness were told that in his abnormal
condition he suffered intense pain or mental anguish in consequence
of particular actions during his normal state, how far would he be
influenced to refrain from such actions by the fear of causing pain
or sorrow to his 'double,' a being of whose pains and sorrows, nay,
of whose very existence, he was unconscious? In ordinary life a man
refrains from particular actions which have been followed by unpleasant
consequences, reasoning, in some cases, 'I will not do so-and-so,
because I suffered on such and such occasions when I did so' (we set
religious considerations entirely on one side by assuming that the
particular actions are not contrary to any moral law), in others, 'I
will not do so-and-so because my so doing on former occasions has
caused trouble to my friend A or B:' but it is strange to imagine any
one reasoning, 'I will not do so-and-so because my so doing on former
occasions has caused my second self to experience pain and anguish,
of which I myself have not the slightest recollection.' A man may
care for his own well-being, or be unwilling to bring trouble on his
friends, but who is that second self that his troubles should excite
the sympathy of his fellow-consciousness? The considerations here
touched on are not so entirely beyond ordinary experience as might be
supposed. It may happen to any man to have occasion to enter into an
apparently unconscious condition during which in reality severe pains
may be suffered by another self, though on his return to his ordinary
condition no recollection of those pains may remain, and though to all
appearance he has been all the time in a state of absolute stupor; and
it may be a reasonable question, not perhaps whether he or his double
shall suffer such pains, but whether the body which both inhabit will
suffer while he is unconscious, or while that other consciousness comes
into existence. That this is no imaginary supposition is shown by
several cases in Abercrombie's treatise on the 'Intellectual Powers.'
Take, for instance, the following narrative:--'A boy,' he tells us, 'at
the age of four suffered fracture of the skull, for which he underwent
the operation of the trepan. He was at the time in a state of perfect
stupor, and after his recovery retained no recollection either of the
accident or of the operation. At the age of fifteen, however, during
the delirium of fever, he gave his mother an account of the operation,
and the persons who were present at it, with a correct description of
their dress, and other minute particulars. He had never been observed
to allude to it before; and no means were known by which he could
have acquired the circumstances which he mentioned.' Suppose one day
a person in the delirium of fever or under some other exciting cause
should describe the tortures experienced during some operation, when,
under the influence of anæsthetics, he had appeared to all around to be
totally unconscious, dwelling in a special manner perhaps on the horror
of pains accompanied by utter powerlessness to shriek or groan, or even
to move; how far would the possibilities suggested by such a narrative
influence one who had a painful operation to undergo, knowing as he
would quite certainly, that whatever pains his _alter ego_ might have
to suffer, not the slightest recollection of them would remain in his
ordinary condition?
There is indeed almost as strange a mystery in unconsciousness as there
is in the phenomena of dual consciousness. The man who has passed for
a time into unconsciousness through a blow, or fall, or fit, cannot
help asking himself like Bernard Langdon in that weird tale, Elsie
Venner, 'Where was the mind, the soul, the thinking principle all that
time?' It is irresistibly borne in upon him that he has been dead for
a time. As Holmes reasons, 'a man is stunned by a blow and becomes
unconscious, another gets a harder blow and it kills him. Does he
become unconscious too? If so, _when_, and _how does he come to his
consciousness_? The man who has had a slight and moderate blow comes
to himself when the immediate shock passes off and the organs begin to
work again, or when a bit of the skull is "pried" up, if that happens
to be broken. Suppose the blow is hard enough to spoil the brain and
stop the play of the organs, what happens then?' So far as physical
science is concerned, there is no answer to this question; but physical
science does not as yet comprehend all the knowable, and the knowable
comprehends not all that has been, is, and will be. What we know and
can know is nothing, the unknown and the unknowable are alike infinite.
FOOTNOTES:
[Footnote 21: Should any doubt whether these conditions of dual
existence are a reality (a doubt, however, which the next case dealt
with in the text should remove), we would remind them that a similar
difficulty unmistakably existed in the case of Eng and Chang, the
Siamese twins. It would have been almost impossible to inflict any
punishment on one by which the other would not have suffered, and
capital punishment inflicted on one would have involved the death of
the other.]
[Footnote 22: An instance of the sort turns up in Pope's correspondence
with Addison, and serves to explain a discrepancy between Tickell's
edition of the _Spectator_ and the original. In No. 253, Addison had
remarked that none of the critics had taken notice of a peculiarity in
the description of Sisyphus lifting his stone up the hill, which is
no sooner carried to the top of it but it immediately tumbles to the
bottom. 'This double motion,' says Addison, 'is admirably described
in the numbers of those verses. In the four first it is heaved up by
several spondees intermixed with proper breathing places, and at last
trundles down in a continual line of dactyls.' On this Pope remarks:
'I happened to find the same in Dionysius of Halicarnassus's Treatise,
who treats very largely upon these verses. I know you will think fit to
soften your expression, when you see the passage, which you must needs
have read, though it be since slipt out of your memory.' These words,
by the way, were the last (except 'I am, with the utmost esteem, &c.')
ever addressed by Pope to Addison. It was in this letter that Pope
with sly malice asked Addison to look over the first two books of his
(Pope's) translation of Homer.]
_ELECTRIC LIGHTING._
Although we certainly have no reason to complain of the infrequency
of attempts in newspapers, &c., as well as in scientific journals, to
explain the principles on which electric lighting depends, it does
not seem that very clear ideas are entertained on this subject by
unscientific persons. Nor is this, perhaps, to be wondered at, when
we observe that in nearly all the explanations which have appeared,
technical expressions are quite freely used, while those matters
about which the general reader especially desires information are
passed over as points with which every one is familiar. Now, without
going quite so far as to say that there is no exaggeration in the
picture presented some time back in _Punch_, of one who asked whether
the electric fluid was 'anything like beer, for instance,' I may
confidently assert that the very vaguest notions are entertained by
nine-tenths of those who hear about the electric light, respecting
the nature of electricity. Of course, I am not here referring to the
doubts and difficulties of electricians on this subject. It is well
known that Faraday, after a life of research into electrical phenomena,
said that when he had studied electricity for a few years he thought
he understood much, but when he had nearly finished his observational
work he found he knew nothing. In the sense in which Faraday spoke, the
most advanced students of science must admit that they know nothing
about electricity. But the greater number of those who read about
the electric light are not familiar even with electrical phenomena,
as distinguished from the interpretation of such phenomena. I am
satisfied that there is no exaggeration in a passage which appeared
recently in the 'Table Talk' of the _Gentleman's Magazine_, describing
an account of the electric light as obtained from some new kind of gas,
carried in pipes from central reservoirs, and chiefly differing from
common gas in this, that the heat resulting from its consumption melted
ordinary burners, so that only burners of carbon or platinum could be
safely employed.
I do not propose here to discuss, or even to describe (in the proper
sense of the word) the various methods of electric lighting which
have been either used or suggested. What I wish to do is to give a
simple explanation of the general principles on which illumination by
electricity depends, and to consider the advantages which this method
of illumination appears to promise or possess.
Novel as the idea of using electricity for illuminating large spaces
may appear to many, we have all of us been long familiar with the
fact that electricity is capable of replacing the darkness of night
by the light of broad day over areas far larger than those which our
electricians hope to illuminate. The lightning flash makes in an
instant every object visible on the darkest night, not only in the
open air, but in the interior of carefully darkened rooms. Nay, even
if the shutters of a room are carefully closed and the room strongly
illuminated, the lightning flash can yet be clearly recognised.
And it must be remembered that though the suddenness of the flash
makes us the more readily perceive it (under such circumstances, for
instance), yet its short duration diminishes its apparent intensity.
This may appear a contradiction in terms, but is not so in reality. The
perception that there has been a sudden lighting up of the sky or of a
room, is distinct from the recognition of the actual intensity of the
illumination thus momentarily produced. Now it is quite certain that
the eye cannot assign less than a twenty-fifth of a second or so to the
duration of the lightning flash, for, as Newton long since showed, the
retina retains the sensation of light for at least this interval after
the light has disappeared. It is equally certain, from Wheatstone's
experiments, that the lightning flash does not actually endure for the
100,000th part of a second. Adopting this last number, though it falls
far short of the truth--the actual duration being probably less than
1,000,000th of a second--we see that so far as the eye is concerned, an
amount of light which was really emitted during the 100,000th part of
a second is by the eye judged to have been emitted during an interval
4,000 times as long. It is certain, then, that the eye's estimate of
the intensity of the illumination resulting from a lightning flash is
far short of the truth. This is equally true even in those cases where
lightning is said to be for awhile continuous. If the flashes for a
time succeed each other at less intervals than a twenty-fifth of a
second, the illumination will appear continuous. But it is not really
so. To be so, the flashes should succeed each other at the rate of at
least 100,000, and probably of more than 1,000,000 per second.
While the lightning flash shows the brilliancy which the electric
illumination can attain, it shows also the intense heat resulting from
the electric discharge. This might, indeed, be inferred simply from the
brilliancy of the light, since we know that this brilliancy can only be
due to the intense heat to which the particles along the track of the
electric flash have been raised. But it is shown in a more convincing
manner to ordinary apprehension by the effects which the lightning
flash produces where--in the common way of speaking--it strikes. The
least fusible substances are melted. Effects are produced also which,
though at first not seemingly attributable to intense heat, yet in
reality can be no otherwise explained. Thus, when the trunk of a tree
is torn into fragments by the lightning stroke, though the tree is
scorched and blackened, a small amount of heat would account for that
particular effect, while the destruction of the tree seems attributable
to mechanical causes. It is, indeed, from effects such as these that
the idea of the fall of thunderbolts has doubtless had its origin,
the notion being that some material substance has struck the body thus
shattered or destroyed. In reality, however, such destructive effects
are due entirely to the intense heat excited during the passage of
the electricity. Thus, in the case of a tree destroyed by lightning,
the shattering of boughs and trunk results from the sudden conversion
of the moisture of the tree (that is, the moisture present in the
substance of the tree) into steam, a change accompanied of course by
great and sudden expansion. The tree is as certainly destroyed by the
effects of heat as is a boiler which has burst, though in each case the
expansive power of steam directly works the mischief.
It is the more useful for our present purpose thus to note at the
outset both the illuminating and the heating power of the lightning
flash (or rather of the electric discharge), because, as will presently
be seen, the electric light, while in all cases depending on intensity
of heat, may either be obtained in the form of a series of flashes
succeeding each other so quickly as to be to all intents and purposes
continuous, or from the incandescence of some suitable substance in the
path of the electric current.
Let us now consider briefly the general nature of electrical phenomena,
or at least of those electrical phenomena which are related to our
present subject.
Formerly, when light was supposed to be a material emanation, and
heat was regarded as an actual fluid, electricity was in like manner
regarded as some subtle fluid which could be generated or dispersed
in various ways. At present, it is safer to speak of electricity
as a state or condition of matter. If it were not that some very
eminent electricians (and one especially whose eminence as a practical
electrician is very great) are said to believe still that there is such
a thing as an electric fluid, we should have simply asserted that in
the present position of scientific research, with the known velocity
at which the so-called electric current flows, and the known relations
between electricity, heat, and light, the theory of an electric fluid
is altogether untenable. It will suffice, however, under the actual
circumstances, to speak simply of electrical properties, without
expressing any definite opinion respecting their interpretation.
A certain property, called electricity, is excited in any substance by
any cause affecting the condition of the substance, whether that cause
be mechanical, chemical, thermal, or otherwise. No change can take
place in the physical condition of any body without the generation of
a greater or less amount of electricity, although in far the greater
number of cases there may be no obvious evidence of the fact, while in
many cases no evidence may be obtainable even by the use of the most
delicate scientific tests.
I have spoken here of the generation of a greater or less amount of
electricity, but in reality it would be more correct to speak simply
of a change in the electrical condition of the substance. Electricians
speak of positive and negative electricity as though there actually
were two distinct forms of this peculiar property of matter. But it
may be questioned whether it would not be more correct to speak of
electricity as we do of heat. We might speak of cold as negative heat
precisely as electricians give the name of negative electricity to a
relative deficiency of what they call positive electricity; but in
the case of heat and cold it is found more convenient, and is more
correct, to speak of different degrees of one and the same quality. The
difficulty in the case of electricity is that at present science has
no means of deciding whether positive or negative electricity has in
reality the better claim to be regarded as absolute electricity. Making
comparison between electrical and thermal relations, the process which
we call the generation of positive electricity may in reality involve
the dispersion of absolute electricity, and so correspond to cooling,
not to heating. In this case the generation of what we call negative
electricity would in reality be the positive process. However, it is
not necessary to discuss this point, nor can any error arise from the
use of the ordinary method of expression, so long as we carefully hold
in remembrance that it is only employed for convenience, and must not
be regarded as scientifically precise.
Electricity may be excited, as I have said, in many ways. With the
ordinary electrical machine it is excited by the friction of a glass
disc or cylinder against suitable rubbers of leather and silk. The
galvanic battery developes electricity by the chemical action of acid
solutions on metal plates. We may speak of the electricity generated
by a machine as frictional electricity, and of that generated by
a galvanic battery as voltaic electricity; in reality, however,
these are not different kinds of electricity, but one and the same
property developed in different ways. The same also is the case with
magnetic electricity, of which I shall presently have much to say:
it is electricity produced by means of magnets, but is in no respect
different from frictional or voltaic electricity. Of course, however,
it will be understood that for special purposes one method of producing
electricity may be more advantageously used than another. Just as heat
produced by burning coal is more convenient for a number of purposes
than heat produced by burning wood, though there is no scientific
distinction between coal-produced heat and wood-produced heat, so for
some purposes voltaic electricity is more convenient than frictional
electricity, though there is no real distinction between them.
Every one knows that when by means of an ordinary electrical machine
electricity has been generated in sufficient quantity and under
suitable conditions to prevent its dispersion, a spark of intense
brilliancy and greater or less length, according to the amount of
electricity thus collected, can be obtained when some body, not
similarly electrified, is brought near to what is called the conductor
of the machine. The old-fashioned explanation, still repeated in many
of our books, ran somewhat as follows:--'The positive electricity of
the conductor decomposes the neutral or mixed fluid of the body,
attracting the negative fluid and repelling the positive. When the
tension of the opposite electricities is great enough to overcome the
resistance of the air, they re-combine, the spark resulting from the
heat generated in the process of their combination.' This explanation
is all very well; but it assumes much that is in reality by no means
certain, or even likely. All we _know_ is, that whereas before the
spark is seen the electrical conditions of the conductor and the object
presented to it were different, they are no longer different after the
flashing forth of the spark. It is as though a certain line (straight,
crooked, or branched) in the air had formed a channel of communication
by which electricity had passed, either from the conductor to the
object or from the object to the conductor,--or _possibly_ in both
directions, two different kinds of electricity existing (before
the flash) in the conductor and the object, as the old-fashioned
explanation assumes.[23] Again, we know that the passage of electricity
along the air-track supposing there really is such a passage, but in
any case the observed change in the relative electrical conditions of
the conductor and the object, is accompanied by the generation of an
intense heat along the aërial track where the spark is seen.
In the case of electricity generated by means of a galvanic battery,
we do not note the same phenomena unless the battery is a strong one.
We have in such a battery a steady source of electricity, but unless
the battery is powerful, the electricity is of low intensity, and
not competent to produce the most striking phenomena of frictional
electricity. For instance, voltaic electricity, as used in telegraphic
communication, is far weaker than that obtained from even a small
electrical machine. What is called the positive extremity of the
battery neither gives a spark, nor attracts light bodies. The same
is true of the other, or negative extremity. The difference of the
condition of these extremities can only be ascertained by delicate
tests--the deflections of the needle, in fact, by which telegraphic
communications are made, may in reality be regarded as the indications
of a very delicate electro-cope.
But when the strength of a galvanic battery is sufficiently great,
or, in other words, when the total amount of chemical action brought
into play to generate electricity is sufficient, we obtain voltaic
electricity not only surpassing in intensity what can be obtained from
electrical machines, but capable of producing spark after spark in a
succession so exceedingly rapid that the light is to all intents and
purposes continuous.
Without considering the details of the construction of a galvanic
battery, which would occupy more space than can here be spared, and
even with fullest explanation would scarcely be intelligible (except to
those already familiar with the subject), unless illustrations unsuited
to these pages were employed, let us consider what we have in the case
of every powerful galvanic battery, on whatever system arranged. We
have a series of simple batteries, each consisting of two plates of
different metal placed in dilute acid. Whereas, in the case of a simple
battery, however, the two different metals are connected together by
wires to let the electric current pass (the current ceasing to pass
when the wires are disconnected), in a compound battery, in which (let
us say) the metals are zinc and copper, the zinc of one battery is
connected with the copper of the next, the zinc of this with the copper
of another, and so on, the wire _to_ the copper of the first battery
and the wire _from_ the zinc of the last battery being free, and
forming what are called the poles of the compound battery--the former
the positive pole, the later the negative pole.[24] When these free
wires are connected, the current of electricity passes, when they are
disconnected the current ceases to pass, unless the break between them
is such only that the electricity can, as it were, force its way across
the gap. When the wires are connected, so that the current flows, it
is as though there were a channel for some fluid which flowed readily
and easily along the channel. When the circuit is absolutely broken,
it is as though such a channel were dammed completely across. If,
however, while the poles are not connected by copper wires or by other
freely conducting substances, yet the gap is such as the electricity
can pass over, the case may be compared to the partial interruption
of a channel at some spot where, though the fluid which passes freely
along the channel is not able to move so freely; it can yet force its
way along, with much disturbance and resistance. Just as at such a part
of the course of a liquid stream--say, a river--we find, instead of
the quiet flow observed elsewhere, a great noise and tumult, so, where
the current of electricity is not able to pass readily we perceive
evidence of resistance in the generation of much heat and light (if the
resistance is great enough).
It will be observed that I have spoken in the preceding paragraph
of the passage of a current along the wire connecting the two poles
of a powerful electric battery, or along any substance connecting
those poles which possesses the property of being what is called a
good conductor of electricity. But the reader is not to assume that
there is such a current, or that it is known to flow either from the
positive to the negative pole, or from negative to positive pole; or,
again, that, as some have suggested, there are two currents which flow
simultaneously in opposite directions. We speak conventionally of the
current, and for convenience we speak as though some fluid really
made its way (when the circuit is complete) from the positive to the
negative pole of the compound battery. But the existence of such a
current, or of any current at all, is purely hypothetical. I should
be disposed, for my own part, to believe that the motion is of the
nature of wave-motion, with no actual transference of matter, at least
when the circuit is complete. According to this view, where resistance
takes place we might conceive that the waves are converted into
rollers or breakers, according to the nature of the resistance--actual
transference of matter taking place through the action of these changed
waves, just as waves which have traversed the free surface of ocean
without carrying onward whatever matter may be floating on the surface,
cast such matter ashore when, by the resistance of the shoaling bottom
or of rocks, they become converted either into rollers or into breakers.
I may also notice, with regard to good conductors and bad conductors
of electricity, that they may be compared to substances respectively
transparent and opaque for light-waves, or again, to substances which
allow heat to pass freely or the reverse. Just as light-waves fail to
illuminate a transparent body, and heat-waves fail to warm a body which
allows them free passage, so electricity-waves (if electricity really
is undulatory, as I imagine) fail to affect any substance along which
they travel freely. But as light-waves illuminate an opaque substance,
and heat-waves raise the temperature of a substance which impedes
their progress, so waves of electricity, when their course is impeded,
produce effects which are indicated to us by the resulting heat and
light.
A powerful galvanic battery is capable of producing light of intense
brilliancy. For this purpose, instead of taking sparks between the
two metallic poles, each of these is connected with a piece of carbon
(which is nearly as good a conductor as the metal), and the sparks are
taken between these two pieces of carbon, usually set so that the one
connected with the negative pole is virtually above the one connected
with the positive pole, and at a distance of a tenth of an inch from
each other or more, according to the strength of the battery. Across
this gap between the carbons an arc of light is seen, which in reality
results from a series of electric sparks following each other in rapid
succession. This arc, called the voltaic arc, is brilliant, but it is
not from this arc that the chief part of the light comes. The ends
of the carbon become intensely bright, being raised to a white heat.
Both the positive and negative carbons are fiercely heated, but the
positive is heated most. As (ordinarily) both carbons are thus heated
in the open air, combustion necessarily takes place, though it is to be
noticed that the lustre of the carbons is not due to combustion, and
would remain undiminished if combustion were prevented. The carbons
are thus gradually consumed, the positive nearly twice as fast as
the negative. If they are left untouched, this process of combustion
soon increases the distance between them till it exceeds that which
the electricity can pass over. Then the light disappears, the current
ceasing to flow. But by bringing the carbon points near to each other
(they must, indeed, be made to touch for an instant), the current is
made to flow again, and the light is restored.
The following remarks by M.H. Fontaine (translated by Dr. Higgs) may
help to explain the nature of the voltaic arc:--'In truth, the voltaic
arc is a portion of the electric circuit possessing the properties of
all other parts of the same circuit. The molecules swept away from
point to point (that is, from one carbon end to the other) 'constitute
between these points a mobile chain, more or less conductive, and
more or less heated, according to the intensity of the current and
the nature and separation of the electrodes' (that is, the quality
and distance apart of the carbon or other substances between which
the arc is formed). 'These things happen exactly as if the electrodes
were united by a metallic wire or carbon rod of small section' (so as
to make the resistance to the current great), 'which is but saying
that the light produced by the voltaic arc and that obtained by
incandescence arise from the same cause--that is, the heating of a
resisting substance interposed in the circuit.'
The intensity of the light from the voltaic arc and the carbon points
varies with circumstances, but depends chiefly on the amount of
electricity generated by the battery. A fair idea of its brilliancy,
as compared with all other lights, will be gained from the following
statements:--If we represent the brightness of the sun at noon on a
clear day as 1,000, the brightness of lime glowing under the intense
heat of the oxy-hydrogen flame is about 7; that of the electric
light obtained with a battery of 46 elements (Bunsen's), 235. With a
battery of 80 elements the brightness is only 238. (These results were
obtained in experiments by Fizeau and Foucault.) The intensity does not
therefore increase much with the number of the component elements after
a certain number is passed. But it increases greatly with the surface,
for the experimenters found that with a battery of 46 elements, each
composed of 3, with their zinc and copper respectively united to form
one element of triple surface, the brightness became 385, or more than
one-third of the midday brightness of the sun (that is, the apparent
intrinsic lustre of his disc's surface), and 55 times the brightness of
the oxy-hydrogen lime-light.
Another way of obtaining an intense heat and light from the electric
current generated by a strong battery is to introduce into the
electric circuit a substance of small conducting power, and capable
of sustaining an intense heat without disintegration, combustion, or
melting. Platinum has been used for this purpose. If the conductive
power of copper be represented by 100, that of platinum will be
represented by 18 only. Thus the resistance experienced by a current in
passing through platinum is relatively so great, that if the current
is strong the platinum becomes intensely heated, and shines with a
brilliant light. A difficulty arises in using this light practically,
from the circumstance that when the strength of the current reaches a
certain point, the platinum melts, and the circuit being thus broken,
the light immediately goes out.
The use of galvanic batteries to generate an electric current strong
enough for the production of a brilliant light, is open to several
objections, especially on the score of expense. It may, indeed, be
safely said that if no other way of obtaining currents of sufficient
intensity had ever been devised, the electric light would scarcely
have been thought of for purposes of general illumination, however
useful in special cases. (In the electric lighting of the New Opera
House at Paris, batteries are used.) The discovery by Orsted that an
electric current can make iron magnetic, and the series of discoveries
by Faraday, in which the relation between magnetism and electricity
was explained, made electric lighting practically possible. One of
these shows that if a properly insulated wire coil is rapidly rotated
in front of a fixed permanent magnet (or of a set of such magnets),
currents will be induced in the coil, which may be made to produce
either alternating currents or currents in one direction only, in wire
conductors. An instrument for generating electric currents in this way,
by rapidly rotating a coil in front of a series of powerful permanent
magnets fixed symmetrically around it, is called a magneto-electric
machine. Another method, now generally preferred, depends on the
rotation of a coil in front of an electro-magnet; that is, of a bar
of soft iron (bent in horseshoe form), which can be rendered magnetic
by the passage of an electric current through a coil surrounding it.
The rapid rotation of the coil in front of the soft iron generates
a weak current, because iron always has some traces of magnetism
in it, especially if it has once been magnetised. This weak current
being caused to traverse the coil surrounding the soft iron increases
its magnetism, so that somewhat stronger currents are produced in
the revolving coil. These carried round the soft iron still further
increase its magnetism, and so still further strengthen the current.
In this way coil and magnet act and react on each other, until from
the small effects due to the initial slight magnetism of the iron,
both coil and the magnet become, so to speak, saturated. Machines
constructed on this principle are called dynamo-electric machines,
because the generation of electricity depends on the dynamical force
employed in rapidly rotating the coils.
We need not consider here the various forms which magneto-electric
and dynamo-electric machines have received. It is sufficient that
the reader should recognise how we obtain an electric current of
great intensity in one case from mechanical action and permanent
magnetism,[25] and in the other from mechanical action and the mere
residue of magnetism always present in iron.
In the cases here considered it is in reality the sudden presentation
of the coil (twice at each rotation) before the positive and negative
poles of the magnet, which induces a momentary but intense current
of electricity. The rotation being exceedingly rapid, these currents
succeed each other with sufficient rapidity to be appreciably
continuous. A similar principle is involved in the use of what is
called the inductive coil, except that in this case the sudden
beginning and ceasing of a current in one coil (and not magnetic
action) induces a momentary but strong current: matters are so arranged
that the current induced by the starting of the inducing current,
immediately causes this to cease; while the current induced by the
cessation of the inducing current immediately causes this current
to begin again: so that by a self-acting process we have a constant
series of intense induced currents, succeeding each other with great
rapidity, so as to be practically continuous, as with those produced by
magneto-electric and dynamo-electric machines.
All that I have said about the voltaic arc, the incandescence
resulting from resistance to the current's flow, and so forth, in
relation to electricity generated by galvanic batteries, applies to
electricity generated by induction coils, or by magneto-electric and
by dynamo-electric machines. Only it is to be noticed that in some of
these machines the currents alternate in direction with each revolution
of the swiftly turning coil, in others the currents are always in the
same direction, and in yet others the currents may be made to alternate
or not, as may be most convenient.
We have now to consider how light suitable for purposes of illumination
may be obtained from the electric current. Hitherto we have considered
only light such as might be used for special purposes, where a bright
and very intense light was required, where expense and complexity of
construction might not be open to special objections, and where in
general the absolute steadiness of the light was not an essential
point. But those who have seen the electric light used even by the
most experienced manipulators for the illustration of lectures will
know that the light as so obtained, though of intense brilliancy, is
altogether unsuited for purposes of ordinary illumination.
If we consider a few of the methods which have been devised for
overcoming the difficulties inherent in the problem of electric
lighting, the reader will recognise at once the nature of these
difficulties, and the probability of their being effectually overcome
in the future, for though much has been done, much yet remains to be
done in mastering them.
Let us consider first the Jablochkoff candle, the invention of which
brought about, in July 1877, the first great fall in the value of gas
property.
The Jablochkoff candle consists of two carbons placed side by side
(instead of one above the other in a vertical line). Thus placed,
with a slight interval between them, the carbon rods would allow the
passage of the electric current at the place of nearest approach, and
therefore of least resistance to its passage. A variable and imperfect
illumination would result. M. Jablochkoff, however, interposes between
the separate carbon rods a slip of plaster of Paris, which is a
non-conducting material. The upper points of the carbon rods are thus
the only parts at which the current can cross. They are connected by
a little bridge of carbon, which is necessary for the starting of the
light--just as in the case of the ordinary electric light, the two
carbons must, in order to start the light, be brought into contact.
When the current flows, the small bridge of carbon connecting the two
points is presently consumed, but the arc between the points is still
maintained: for the plaster becomes vitrified by the intense heat of
the two carbon points on each side, and melts down as the carbons are
consumed. If the light is in any way put out, however, a small piece of
carbon must be set again, to form a bridge between the carbon points.
Throughout the burning of the Jablochkoff candle the fused portion
of the insulating layer forms a conducting bridge between the carbon
points; and hence there is a considerable loss of electric force
(probably about thirty per cent.), which in the ordinary arrangement
would increase the intensity of the light. The great advantage of the
candle consists in the circumstance that throughout its consumption
the carbon ends are at a constant distance from each other without any
mechanical or other arrangement being necessary to maintain them in due
position.
One point should be noticed here. In the ordinary arrangement of carbon
points, the positive carbon, as we have already said, is much more
intensely heated, and consumes twice as fast as the negative carbon.
Now, if one carbon of the Jablochkoff candle were connected with the
positive, and the other with the negative pole of the battery or of a
machine, the former side would consume twice as fast as the latter, and
the two points would no longer remain at the same horizontal level,
which is essential to the proper burning of the Jablochkoff candle.
By using a machine which produces alternating currents, M. Jablochkoff
obviates this difficulty, the carbons being alternately positive and
negative (in extremely rapid succession), and therefore consuming at
the same rate.
The Jablochkoff candle lasts only about an hour and a half. But four,
six, or more candles may be used in the same globe or lantern, and
automatic arrangements adopted to cause a fresh candle to be ignited at
the moment when its predecessor is burnt out.
In Paris and elsewhere (as in Holborn, for instance), each Jablochkoff
lamp is enclosed in an opal glass globe. Mr. Hepworth remarks on this,
that in his opinion the use of the opal globe is a mistake, as it
shuts off quite 50 per cent. of the light without any corresponding
advantage, except the correction of the glare. 'This wasteful
disadvantage will no doubt be remedied in the future,' he says, by
the use of some less dense medium. 'Mr. Shoolbred states that from a
series of careful photometric experiments carried out by the municipal
authorities with the Jablochkoff lights, each naked light is found to
possess a maximum intensity of 300 candles. With the opal globe this
was reduced to 180 candles, showing a loss of 40 per cent., while
during the darker periods through which the light passed the light
was as low as 90 candles. It may be mentioned here that Mr. Van der
Weyde, who has long used the electric light for photographic purposes,
has given much attention to the important problem of rendering the
electric light available as an illuminator without wasting it, and yet
without throwing the rays directly upon the object to be illuminated.
The rays are intercepted by an opal disc about four inches in diameter,
and the whole body of the rays is gathered up by a concave reflector
(lined with a white material), and thrown out in a flood of pure white
light, in which the most delicate shades of tint are discernible. He
can use any form of electric candle in this way. Only it should be
noticed, before the employment of his method is advocated for street
illumination, that there is a difference between the problems which
the photographer and the street-lighter have to solve. The Jablochkoff
candle, for instance, must be screened on all sides, and even above,
when used to illuminate the streets. If its direct light is allowed
to escape in any direction, there will be a mischievous and unsightly
beam, and from every point along the path of the beam, the intensely
bright light of the candle will be directly visible. Again: it is
essential that whatever substance is used to screen the light should
be dense enough to cause the whole globe to seem uniformly bright or
nearly so. The only modification which seems available (when these
essential points have been secured) is that the tint of the globe
should be such as to correct any colour which the light may be found to
have in injurious excess. We may, however, remark that the objection
which has been often raised against the colour of the electric light
can hardly be just--the injury to the eyes in certain cases arising
probably from the strong contrast between the light and the background
on which it is projected. For, as to colour, the electric light
derived either from the glowing carbon or from incandescent metal is
appreciably the same as sunlight.
The Rapieff burner, employed in the 'Times' office, consists of four
carbon pencils, arranged thus [Symbol] (except that the two v's are
not in the same plane, but in planes at right angles to each other).
The spark crosses the space between the points of the v's, and
arrangements are made for keeping the two points at the right distance
from each other, and also for keeping the ends of the two pencils which
form each point in their proper position. If the current is from any
cause interrupted, an automatic arrangement is adopted to allow the
current to pass to the other lamps in the same circuit. There are
six lamps in circuit at the 'Times' office; and M. Rapieff has
exhibited as many as ten. The advantages claimed for this
light are the following:--'First, its production by any description
of dynamo-electric machine with either alternating or continuous
currents; secondly, great diversibility and complete independence
of the several lights, and long duration without change of carbons;
and lastly, the extreme facility with which any ordinary workman or
servant can renew the carbons when necessary, without extinguishing
the lights.' The last-named advantage results, it need hardly perhaps
be said, from the use of two carbons to form each point. One can be
removed, the other remaining to keep the voltaic arc intact until a
new carbon has been substituted for its fellow; then it in turn can be
replaced by a new carbon, the new carbon already inserted keeping the
voltaic arc intact.
The six lamps at the 'Times' office thoroughly illuminate the room, and
give light for working the eight Walter presses used in printing the
paper. The light has been thus used since the middle of last October,
and it is said that other rooms in the building are shortly to be
illuminated in the same manner. 'Each lamp is enclosed in an opal globe
of about four inches in diameter, and so little heat is given off, that
the hand can be placed on the globe without inconvenience, even after
the light has been burning for some time.'
In the Wallace lamp there are two horizontal plates of carbon, about
nine inches in diameter, instead of mere carbon points. When the
current is passing, these carbon plates are separated by a suitable
small distance which remains unchanged. The electric arc, being started
at the point along the edge of the carbons where there is least
resistance to the passage of the current, gradually passes along the
edge of the carbons as combustion goes on, changing the position of
the place of nearest approach and consequently of least resistance.
The light will thus burn for many hours (even for a hundred with large
carbon plates), and any number of lights up to ten can be worked from
the machine. The objection to the Wallace lamp is, that the light does
not remain at one point, but travels along the whole extent of the
carbons. It will not be easy to design a glass shade which will be
suitable for a light thus changing in position.
The Werdermann regulator is on an entirely new plan; but it has not yet
been submitted to the test of practical working outside the laboratory.
The positive carbon, which is lowest, ends in a sharp point, which
strangely enough retains its figure, while the carbon burns away at
the rate of about two inches per hour. The negative carbon is a block
having its under side, against which the positive carbon presses,
slightly convex. The positive carbon is pressed steadily against the
negative by the action of a weight. The increased resistance to the
passage of the current, at the sharp point of the positive carbon,
generates sufficient heat to produce a powerful light. The light
resembles a steadily radiant star, but 'with all its softness and
purity of tint, it is so intense, that adjacent gas-flames are thrown
on the wall as transparent shadows.' The light will last for fifteen
hours without attention, the positive carbon rod being used in lengths
of three feet. The carbon block hardly undergoes any change. When the
lamp has been burning a long time, a slight depression can be seen
at the place where the positive carbon touches it, but by shifting
the carbon in its holder this is easily remedied. Mr. Werdermann
lately exhibited a row of ten small lamps burning side by side at the
same time. 'The two wires from the machine,' says Mr. Hepworth, were
carried one on either side of this row of lamps, branch wires being led
from them for the service of each lamp. Mr. Werdermann says that his
perfected lamps will be furnished with keys, by which the current can
be turned on or off, as in the case of gas. We may say in fact, that
in the nature of its connections and various arrangements, it ("the
Werdermann lamp") most nearly comes up in convenience to the use of
gas.'
We do not yet know certainly what arrangement Mr. Edison employs to
obtain the light of which so much has been heard. It is asserted that
his light is obtained from the incandescence of an alloy of iridium and
platinum, which will bear without fusion a heat[26] of 5,000 degrees
Fahrenheit. It would be unsafe, however, to assume that this account is
trustworthy, or to infer (as we might in the case of almost any other
inventor), that such being the nature of his plan, it could lead to no
result of practical value. As has been well remarked by a contemporary
writer, whatever Edison's invention may be, 'it is certain to be
something to command respect, even if it does not quite come up to the
glowing accounts which have reached us in advance.'
The following passage from one of these accounts, which appeared in the
'New York Herald,' will be read with interest, and may be accepted as
trustworthy so far as it goes. 'The writer last night saw the invention
in operation in Mr. Edison's laboratory. The inventor was deep in
experimental researches. What he called the apparatus consisted of a
small metal stand placed on the table. Surrounding the light was a
small glass globe. Near by was a gas jet burning low. The Professor
looked up from his work, to greet the reporter, and in reply to a
request to view the invention, waved his hand towards the light, with
the exclamation, "There she is!" The illumination was such as would
come from a brilliant gas jet surrounded with ground glass, only that
the light was clearer and more brilliant. "Now I extinguish it and
light the gas, and you can see the difference," said Mr. Edison, and
he touched the spring. Instantly all was darkness. Then he turned on
the gas. The difference was quite perceptible. The light from the gas
appeared in comparison tinted with yellow. In a moment, however, the
eye had become accustomed to it, and the yellowish tint disappeared.
Then the Professor turned on the electric light, giving the writer the
opportunity of seeing both, side by side. The electric light seemed
much softer; a continuous view of it for three minutes did not pain
the eye; whereas looking at the gas for the same length of time caused
some little pain and confusion of sight. One of the noticeable features
of the light, when fully turned on, was that all the colours could
be distinguished as readily as by sunlight. "When do you expect to
have the invention completed, Mr. Edison?" asked the reporter. "The
substance of it is all right now," he answered, putting the apparatus
away and turning on the gas. "But there are the usual little details
that must be attended to before it goes to the people. For instance, we
have got to devise some arrangement for registering a sort of meter,
and again, there are several different forms that we are experimenting
on now, in order to select the best." "Are the lights to be all of the
same degree of brilliancy?" asked the reporter. "All the same!" "Have
you come across any serious difficulties in it as yet?" "Well, no,"
replied the inventor, "and that's what worries me, for in the telephone
I found about a thousand;[27] and so in the quadruplex. I worked on
both over two years before I overcame them."'
Other methods, as the Sawyer-Man system, and the Brush system, need not
at present detain us, as little is certainly known respecting them. In
the former it is said that the light is obtained from an incandescent
carbon pencil, within a space containing nitrogen and no oxygen, so
that there is no combustion. In the latter the carbon points are placed
as in the ordinary electric lamp, but are so suspended in the clasp of
a regulator, that they burn 14 inches of carbon without adjustment, the
carbons lasting eight hours, and producing a flood of intense white
light, estimated as equivalent to 3,000 candles.
I have little space to consider the cost of electric lighting, even
if the question were one which could be suitably dealt with in these
pages. Opinions are very much divided as to the relative cost of
lighting by gas and by electricity; but the balance of opinion seem to
be in favour of the belief that in America and France certainly, and
probably in this country, where gas is cheap, electric lighting will
on the whole be as cheap as lighting by gas. It should be noticed,
in making a comparison between this country and others in which coal
is dearer, that the cheapness of coal here, though favourable in the
main to gas illumination, is also favourable, though in less degree
(relatively) to electric lighting. Machines for generating electricity
can be worked more cheaply here than in America. Nay, it has even
been found advantageous in some cases to use a gas engine to generate
electricity. Thus Mr. Van der Weyde used an Otto gas engine driven
at the cost of 6_d._ an hour for gas, to produce the light which he
exhibited publicly on the night of November 9. So that the cheapness of
gas may make the electric light cheaper. Then it is to be remembered
that important though the question of cost is, it is far from being
all-important. The advantages of electric lighting for many purposes,
as in public libraries, in cases where many persons work together
under conditions rendering the vitiation of the air by gas lighting
exceedingly mischievous, and in cases where the recognition of delicate
differences of tint or texture is essential, must far more than
compensate for some slight difference in cost. The possibility (shown
by actual experience to be real) of employing natural sources of power
to drive machines for generating electricity, is another interesting
element of the subject, but could not be properly dealt with save in
greater space than this here available.
FOOTNOTES:
[Footnote 23: It is supposed by many, that when the spark is long
enough we can note the direction in which it travels; and observations
of the motion of lightning from the earth to the cloud have been
collected, as showing that the usually observed direction of the flash
is sometimes reversed. In reality, no one has ever seen a lightning
flash travel either one way or the other. If the attention is fixed
on the storm cloud, as usual when a lightning storm is watched, every
flash appears to pass from the cloud to the earth. If, on the contrary,
at the moment when the attention is fixed on some terrestrial object
the lightning flashes near that particular object, the flash will seem
to pass from the object to the cloud. In either case the motion is
apparent only. If there is motion at all, the passage of the electric
spark occupies less than the 100,000th part of a second, and of course
it is utterly impossible that any eye could tell at which end of its
track the flash first appeared. In every case the flash seems to travel
from the end to which attention was more nearly directed. The apparent
motion corresponds to the chance direction of the eye.]
[Footnote 24: The extremity of the wire connected with the metal least
affected by the acid solution is called the positive pole, that of the
wire connected with the metal most affected by the solution is called
the negative pole.]
[Footnote 25: So called, though in reality the best magnets gradually
lose force.]
[Footnote 26: My occasional use of the word 'heat' where in scientific
writing 'temperature' would be the word used, has exposed me to
peevish, not to say petulant comments from Professor P.G. Tait, who
has denounced half the mathematical world for using the word 'force,'
in the sense in which Newton used it, and has spoken of an eminent
physicist as one deserving universal execration and opprobrium for
not explaining, when speaking of work done against gravity, that
terrestrial gravity was meant, and not gravity on the sun, or Jupiter,
or Mars, or anywhere in the heavens above or in the earth beneath,
but only at the earth's surface. Where there is no risk of confusion,
the word 'heat' may be used either to signify temperature, as when
in ordinary speech and writing we talk of blood-heat, fever-heat,
summer-heat, and so forth. Science, indeed, very properly forbids
the use of the word in any sense save one. But outside the pages of
scientific treatises, there is no inaccuracy in using a word in a sense
popularly attributed to it, when no mistake can possibly arise. No one
can suppose, when I speak of a heat of so many degrees Fahrenheit or
Centigrade, that I mean anything but such and such a degree of heat,
any more than if I spoke of the intense heat of that _savant entêté_,
Professor P.G. Tait, any one would imagine that I referred to his
calorific condition.]
[Footnote 27: The comments made by one of Mr. Edison's assistants
on this point are interesting and instructive. 'Mr. Batchelor, the
Professor's assistant, who here joined in the conversation,' proceeds
the report of the _Herald_, 'said, "Many a time Mr. Edison sat down
almost on the point of giving up the telephone as a lost job; but at
the last moment, he would see light." "Of all things that we have
discovered, this is about the simplest," continued Mr. Edison, "and the
public will say so when it is explained. We have got it pretty well
advanced now, but there are some few improvements I have in my mind.
You see, it has got to be so fixed that it cannot get out of order.
Suppose when one light only is employed it got out of order once a
year, where two were used it would get out of order twice a year, and
where a thousand were used you can see there would be much trouble in
looking after them. Therefore, when the light leaves the laboratory, I
want it to be in such a shape that it cannot get out of order at all,
except of course by some accident."']
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