| By Author | [ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z | Other Symbols ] |
| By Title | [ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z | Other Symbols ] |
| By Language |
|
Download this book: [ ASCII ] Look for this book on Amazon Tweet |
Title: The American Electro Magnetic Telegraph - With the Reports of Congress, and a Description of All - Telegraphs Known, Employing Electricity or Galvanism
Author: Vail, Alfred
Language: English
As this book started as an ASCII text book there are no pictures available.
*** Start of this LibraryBlog Digital Book "The American Electro Magnetic Telegraph - With the Reports of Congress, and a Description of All - Telegraphs Known, Employing Electricity or Galvanism" ***
Transcriber’s Notes:
Underscores “_” before and after a word or phrase indicate _italics_
in the original text.
Small capitals have been converted to SOLID capitals.
Illustrations and footnotes have been moved so they do not break up
paragraphs.
Old or antiquated spellings have been preserved.
Typographical errors have been silently corrected.
THE AMERICAN
ELECTRO MAGNETIC TELEGRAPH:
WITH THE
REPORTS OF CONGRESS,
AND A DESCRIPTION
OF ALL TELEGRAPHS KNOWN,
EMPLOYING ELECTRICITY OR GALVANISM.
ILLUSTRATED BY EIGHTY-ONE WOOD ENGRAVINGS.
BY ALFRED VAIL,
ASSISTANT SUPERINTENDENT OF ELEC. MAG. TEL. FOR THE U. S.
CANST THOU SEND LIGHTNINGS, THAT THEY MAY GO,
AND SAY UNTO THEE, HERE WE ARE?—JOB.
“The same principle which justified and demanded the
transference of the mail on many chief routes, from the
horse-drawn coach on common highways to steam-impelled
vehicles on land and water, is equally potent to warrant
the calling of the electro magnetic telegraph—that last
and most wondrous birth of this wonder-teeming age—in aid
of the post office, in discharge of its great function of
rapidly transmitting correspondence and intelligence.”
REP. OF COM. OF WAYS AND MEANS OF H. R., 1845.
PHILADELPHIA:
LEA & BLANCHARD.
1845.
ENTERED, according to Act of Congress, in the year 1845,
By ALFRED VAIL,
In the Clerk’s Office of the District Court of the United States,
in and for the District of Columbia.
CONTENTS.
DESCRIPTION OF THE AMERICAN ELECTRO MAGNETIC TELEGRAPH.
PAGE.
Introduction, 7
The Galvanic Battery, 9
The Wire, 13
The Electro Magnet, 13
The Register, 18
The Correspondent, 22
The two Dependent Circuits, 23
The two Independent Circuits, 24
The operation of the Electro Magnetic Telegraph, 25
The Telegraphic Alphabet, 27
Specimen of the Telegraphic Language, 28
Telegraphic Alphabets for two, three, four, five, and six pens,
operating together, or in succession, 30
Correspondent or Key, 32
The Lever Key, 40
The Circuit of the Electro Magnet, closed and broken by the
movement of the Lever itself, acted upon by the Electro
Magnet. Showing the rapidity with which it is possible to
close and break the Circuit, 41
Conducting Power and Galvanic action of the Earth, 43
Six Independent Circuits, with Six Wires, each wire making an
Independent Line of Communication, 44
Mode of Secret Correspondence, 46
Experiments made with 100 pairs of Grove’s Battery, passing
through 160 miles of insulated wire, 53
The Galvanometer or Galvanoscope, 57
An Interesting Experiment of supporting a Large Bar of Iron
within the Helix, 59
Application of the Electro Magnetic Telegraph to the
Determination of Longitude, 59
Mode of Crossing Broad Rivers, or other Bodies of Water
Without Wires, 60
Telegraphic Chess Playing, 63
Improvement in the Magneto Electric Machine, and Application
of this Instrument to operate the Magnetic Telegraph, 65
REPORTS OF CONGRESS ON THE SUBJECT OF ELECTRO MAGNETIC TELEGRAPHS.
Letter from the Secretary of the Treasury, transmitting a
Report upon the Subject of a System of Telegraphs for the
United States, December, 11, 1837, 67
Circular to certain Collectors of the Customs, Commanders of
Revenue Cutters, and other persons, March 10th, 1837, 68
Letter from S. F. B. Morse to the Secretary of the Treasury,
September 27, 1837, 69
Letter from S. F. B. Morse to the Secretary of the Treasury,
November 28th, 1837, 73
Letter from S. F. B. Morse to the Editors of the
Journal of Commerce, Sept’r 4, 1837, 74
Specimen of Telegraphic Writing made by Means of Electricity,
at the distance of one-third of a mile, 75
Report of the Committee on Commerce to the House of
Representatives, April 6, 1838, 76
Report of the Franklin Institute, Philadelphia,
February 8, 1838, 79
Letter from S. F. B. Morse to the Hon. F. O. J. Smith,
February 15, 1838, 80
Letter from S. F. B. Morse to the Hon. F. O. J. Smith,
February 22, 1838, 82
Report of the Committee on Commerce to the House of
Representatives, Dec’r 30, 1842, 83
A Bill to test the Practicability of Establishing a System
of Electro Magnetic Telegraphs by the United States, 87
Letter from Professor Henry to Professor Morse,
February 24, 1842, 87
Report of the American Institute on the Electro Magnetic
Telegraph, Sept’r 12, 1842, 88
Letter from S. F. B. Morse to the Hon. C. G. Ferris,
December 6, 1842, 89
Communication from the Secretary of the Treasury,
transmitting the Report of Professor Morse, announcing
the Completion of the Electro Magnetic Telegraph, between
the Cities of Washington and Baltimore, June 4, 1844, 97
Letter from S. F. B. Morse to Hon. McClintock Young,
June 3, 1844, 98
Letter from the Secretary of the Treasury, transmitting
a Letter from S. F. B. Morse, relative to the Magnetic
Telegraph, December 23, 1844, 101
Letter from S. F. B. Morse to the Hon. G. M. Bibb,
December 12, 1844, 101
Report of the Committee of Ways and Means to the House of
Representatives, March 3, 1845, 107
HISTORY OF TELEGRAPHS EMPLOYING ELECTRICITY IN VARIOUS WAYS FOR THE
TRANSMISSION OF INTELLIGENCE.
Discoveries in Electricity, 115
Electrical Feast on the Schuylkill, 119
Dr. Franklin’s Experiment in Drawing Electricity
from the Clouds, 120
Lomond’s Electrical Telegraph, (1787,) 121
Reizen’s Electric Spark Telegraph, (1794,) 121
Dr. Salva’s Electric Spark Telegraph, (1798,) 123
Discovery of Galvanism, (1790,) 123
Discovery of the Decomposition of Water by the Agency of
the Galvanic Pile, 125
Samuel Thomas Soemmering’s Voltaic Electric Telegraph, (1809,) 126
Extract from the Journal of the Franklin Institute in relation
to the Use of Galvanism for Telegraphic Purposes, (1816,) 128
Ronald’s Electric Telegraph, (1816,) 130
Discovery of Electro Magnetism, (1819,) 132
Extract from a Work on Electro Magnetism, published by
Jacob Green, M. D. (1827,) 134
Triboaillet’s Proposition, (1828,) 135
Fechner’s Suggestion, (1829,) 135
Discovery of Magneto Electricity, (1831,) 135
Saxton’s Magneto Electric Machine, 142
Dr. Page’s Magneto Electric Machine, 145
Pole Changer, 149
Morse’s American Electro Magnetic Telegraph, (1832,) 152
Schilling’s Electric Telegraph, (1833,) 155
Gauss and Weber’s Electro Magnetic Telegraph, (1833,) 156
Experiments of Messrs. Taquin & Ettieyhausen, (1836,) 159
Vail’s Electro Magnetic Printing Telegraph, (1837,) 159
Wheatstone’s Electric Needle Telegraph, (1837,) 171
Steinheil’s Electric Telegraph, (1837,) 179
Masson’s Electric Telegraph, (1837,) 182
Davy’s Needle and Lamp Telegraph, (1837,) 182
Alexander’s Electric Telegraph, (1837,) 184
M. Amyot’s Suggestion of an Electric Telegraph, (1838,) 186
Edward Davy’s Electric Telegraph, (1838,) 187
Bain’s Printing Telegraph, (1840,) 199
Wheatstone’s Rotating Disc Telegraph, (1841,) 203
INTRODUCTION.
The propriety of presenting to the public a work of this character,
seemed desirable, from the frequent calls made upon the author for
some accurate and full description of the American Electro Magnetic
Telegraph, which might assist to an intelligible comprehension of the
principles upon which it is based, and the mode of its operations,
as well as descriptions of those plans now in operation in Europe.
In the execution of this task it has been his determination to spare
no labour, and to omit nothing that could enable those who had never
seen the operation of the telegraph, to obtain a full understanding,
of the subject, and also to judge for themselves of the merit of the
American invention, as compared with those of Europe. For this purpose
eighty-one wood cuts are introduced to illustrate this and collateral
subjects.
The various reports of Congress which have been made, from time to
time, as the subject of the Electro Magnetic Telegraph has been
presented to them, have been embraced in the work. They contain much
information in relation to the origin and progress of the invention,
as well as other useful matter. In the closing part of the work
is given a synopsis of the early discoveries in electricity; the
experiment of Franklin, and also the discoveries of ingenious and
scientific gentlemen of the present day. The principal part, however,
is devoted to a full and complete description of the various plans of
telegraphic communication, by means of electricity and galvanism, in
the chronological order of their invention; by which it will be seen,
that for priority as well as originality, America has the pre-eminence,
not only at the time of the invention, but up to the present period;
nothing having yet been brought forward that fulfils so completely the
conditions of what is signified by the term _telegraph_, as that plan
invented by Professor Morse. Some of the foreign plans the author has
found extremely difficult to illustrate, without almost re-inventing
them, so imperfectly and obscurely have they been described.
The experimental line from Washington to Baltimore has been in
successful operation for more than a year, and has been the means of
conveying much important information: consisting of messages to and
from merchants, members of Congress, officers of the government, banks,
brokers, police officers; parties, who by agreement had met each other
at the two stations, or had been sent for by one of the parties; items
of news, election returns, announcement of deaths, inquiries respecting
the health of families and individuals, the daily proceedings of the
Senate and House of Representatives, orders for goods, inquiries
respecting the sailing of vessels, proceedings of cases in the various
courts, summoning of witnesses, messages in relation to special and
express trains, invitations, the receipt of money at one station and
its payment at the other, for persons requesting the transmission of
funds from debtors, consultation of physicians, and messages of every
character usually sent by mail.
The author trusts that the work will be received as one of a practical
character, and furnish to those desirous to acquaint themselves with
the subject, such information as they seek.
ALFRED VAIL.
WASHINGTON, D. C. _August 18, 1845_.
THE ELECTRO MAGNETIC TELEGRAPH.
THE GALVANIC BATTERY.
The galvanic battery, the generator of that subtle fluid, which
performs so important a part in the operation of the Electro Magnetic
Telegraph, is as various in its form and arrangement, as the variety of
purposes to which it is applied. They all, however, involve the same
principle. It is not our design here to describe the various modes of
constructing it, but to confine our remarks more immediately to that
used for the Telegraph.
The effects produced by the galvanic fluid upon the metallic bodies,
iron and steel, exciting in them the power of attraction or magnetism,
its decomposing effects upon liquids, resolving them into their simple
elements, its effects upon the animal system, in producing a spasmodic
and sudden irritation, are generally well known. But of the character
of the fluid itself, its own essence or substance, we know nothing. In
some of its phenomena, it resembles the electricity of the heavens;
both find a conductor in the metals; both exhibit a spark, and both
are capable of producing shocks, or when applied, cause the animal
system to be sensible to them. Again, in other of its phenomena it
is totally unlike it. The galvanic fluid is essentially necessary in
producing the electro magnet; while the electricity of the heavens, or
as it is generally termed, _machine electricity_, has no such power for
practical purposes. The former is more dense, so to speak, and more
easily confined to its conductors, while the latter becomes dissipated
and lost in the atmosphere long before it has reached the opposite
extremity of a long conductor. The former is continuous in its supply;
while the latter is at irregular intervals. The former always needs
a continuous conductor; while the latter will pass from one metallic
conductor to another without that connection. The latter would not
subserve the purposes required in the working of the Electro Magnetic
Telegraph, and as it is neither essential nor antagonistical, its
presence upon the galvanic conductors or wires, at the same time those
wires are being used for telegraphic communication, does in no way
interrupt or confuse its operation; and its presence is only known from
the suddenness of its discharge at long intervals, accompanied by a
bright spark, with a loud crack, like that of a coachman’s whip.
The most simple mode of developing the galvanic fluid is in the
following manner: if a common glass tumbler is two-thirds filled
with dilute muriatic acid, and a piece of bright zinc, five inches
long and one inch wide, immersed in the liquid, at one of its ends,
slight action will be discovered upon it. If a slip of copper be then
taken, of the same dimensions, and one end immersed in the liquid, but
separated from that portion of the zinc immersed, and not permitted to
touch it; and the two projecting ends of the zinc and copper, above the
liquid be brought in contact, an active decomposition of the muriatic
acid will appear.
While the two outer ends are in contact, there is that current formed
in the metallic plates, which is termed galvanic. If the contact is
broken, the action ceases; if it is again renewed, the action is
recommenced. Another very simple experiment, and within the power of
every one to demonstrate for themselves, is that of applying a piece
of zinc to the underside of the tongue, and to the upperside, a silver
coin, and then by bringing their projecting ends in contact, a sensible
and curious effect is experienced upon the tongue. It is a feeble
galvanic shock, and is proof of the presence of that fluid termed
galvanic.
We will now proceed to describe the battery used for telegraphic
purposes; the same in principle, but in arrangement more complicated,
and far more powerful than those in common use. Two distinct acids
are employed; two metals and two vessels. Each part will be described
separately, and then the whole, as put together ready for use.
First. A glass tumbler of the ordinary size is used, or about three
inches high and two inches and three quarters in diameter.
Second. The zinc cylinder, made of the purest zinc, and cast in an iron
mould, represented by figure 1.
[Illustration: FIG. 1.]
It is three inches high, and two inches in diameter. The shell I
is three-eighths of an inch in thickness. D is an opening in the
cylinder, parallel with its axis, and is of no other use than to aid
in the operation of casting them, and facilitating the access of the
fluid to the interior. A A represents the body of the cylinder. B is
a projecting arm, first rising vertically from the shell, and then
projecting horizontally one and three quarters of an inch. To this arm,
at C, is soldered a platinum plate of the thickness of tin foil, and
hanging vertically from the arm B, as seen at O, and of the form shown
in the figure. This constitutes the zinc cylinder and platinum plate,
the two metals used in the battery.
[Illustration: FIG. 2.]
Third. The porous cup. To avoid an erroneous impression in the use of
the term porous, it will suffice to state, that it is a cup of the form
represented by figure 2, made of the same materials as stone-ware, and
baked without being _glazed_.[1] A represents the rim surrounding the
top. From the under side of the rim to the bottom, it is three inches
long, and one and one-quarter in diameter. The rim projects one-quarter
of an inch, and the shell of the cup is one-eighth of an inch
thick. These several parts are placed together thus. The porous cup,
fig. 2, is set in the hollow of the zinc cylinder, fig. 1, represented
by H, with the rim of the cup resting upon the top of the zinc at I.
The zinc cylinder is then placed in the glass tumbler. The whole is
represented in figure 3.
[1] These are made at the American Pottery, in Jersey City, opposite
New York.
[Illustration: FIG. 3.]
D represents the porous cup, F the zinc cylinder, G the glass tumbler,
A the projecting arm of the zinc, C the platinum plate, and B the
over-lapping of the platinum plate upon the zinc arm, where it is
soldered to it. It is now in a condition to receive the acids, which
are two: first, pure nitric acid, and second, sulphuric acid, diluted
in the proportion of one part of sulphuric acid to twelve of water.
First fill the porous cup with the nitric acid, to within one-quarter
of an inch of the top; then fill the glass with the diluted sulphuric
acid, till it reaches to a level with the nitric acid in the porous
cup. One glass of the battery is now ready for use, and as all the
other members of the battery are similarly constructed, (there being
many or few, as circumstances require,) and are to be prepared and
filled with their appropriate acids in the same manner, the above
description will suffice. There remains, however, some further
explanation in regard to the extremities of the series of glasses,
that is, the mode of connecting the zinc of the first glass with the
wire leading from it, and also the mode of connecting the platinum of
the last glass with the wire leading from that end of the series of
glasses. Figure 4 represents their arrangement.
[Illustration: FIG. 4.]
The glasses being all separately supplied with their acids, and
otherwise prepared, they are put together upon a table, A A, perfectly
dry, and made of hard wood. The first member of the series has soldered
to its zinc arm a strip of copper, C, which, extending downward, has
its end, previously brightened and amalgamated, immersed in a cup of
mercury at N. The cup being permanently secured to the table. Then the
second glass is taken, and the platinum, B, at the end of the zinc arm,
is gently let fall into the porous cup, so that it shall be in the
centre of the cup, and reaching down as far as its length, when the
glass rests upon the table. The third glass is then taken and placed
in the same manner, and so on to the last. The last glass has, in its
porous cup, the platinum plate, D, soldered to a strip of copper, E,
which is so constructed as to turn at the top, and admit of the easy
introduction of the platinum into the porous cup, while the other end
of the copper, previously prepared like the copper of the other end of
the battery, terminates in a cup of mercury, P. The cup being capable
of adjustment, so as to bring the platinum directly over the porous
cup; is, when adjusted, secured permanently to the table. The battery,
thus arranged, is ready to be applied.
THE WIRE.
The wire used in making helices for the magnets, and for connecting
the telegraphic stations, is made of copper of the best quality, and
annealed. It is covered with cotton thread, so as to conceal every part
of the metallic surface, not so much to prevent corrosion or waste
from the action of the atmosphere, as to prevent a metallic contact of
one wire with another, when placed near each other. After the wire is
covered, it is then saturated with shellac, and then, again, with a
composition of asphaltum, beeswax, resin and linseed oil. It is now in
a condition to be extended upon the poles. That portion of the wire of
which the helices are made is only saturated with shellac.
THE ELECTRO MAGNET.
The electro magnet is the basis upon which the whole invention rests
in its present construction; without it, it would entirely fail. As
it is of so much importance, a detailed account will be given of the
construction of the electro magnet, as used for telegraphic purposes.
A bar of soft iron, of the purest and best quality, is taken and made
into the form presented in figure 5, which consists of four parts,
viz. A F and A F are the two legs or prongs of the magnet,[2] of a
rounded form, and bent at the top, approaching each other towards the
centre, where the ends of each prong, without touching, turn up, and
present flat, smooth and clean surfaces, level with each other at F F.
The other end of these prongs or legs is turned smaller than the body,
on the end of which is a screw and nut, C C. These ends pass through
a plate of iron, B, of the same quality, at I and I, until they rest
upon the plate at the shoulder produced by turning them smaller. They
are then both permanently secured to the plate, B, by the nuts, C C,
and the whole becomes as one piece. This arrangement is made for the
purpose of putting on the coils or taking them off with facility. The
form most common for electro magnets is that of the horse-shoe; and is
simply a bar of iron bent in that form. E represents a small flat plate
of soft iron, sufficiently large to cover the faces of the two prongs,
F and F, presenting on its under side a surface clean and smooth, and
parallel with the faces, F and F.
[2] The term _magnet_, here, is synonymously used with the iron for
the magnet, as the simple iron is not a magnet, except when subjected
to the action of the battery through the helices of wire around it.
It would confuse the reader, if this distinction be not kept in view.
_Permanent magnets_ are those which retain their magnetism when once
they are charged. They are always made of steel, and usually bent in
the form of a horse-shoe. Sometimes they are of a single plate of
that form, and others are constructed with many plates, side by side,
fastened together so as to present a compact magnet of the same form.
They are distinguished from _Electro Magnets_ from the fact, that the
soft iron of the latter depends upon the influence of the galvanic
fluid for its magnetism, and retains it only so long as the soft iron
is under its influence, while the former, when once submitted to the
influence of the galvanic fluid, retain their magnetism permanently.
[Illustration: FIG. 5.]
The coils or helices of wire, which surround the prongs, A A, necessary
to complete the electro magnet, consist of many turns of wire, first
running side by side, covering the form upon which the spiral is made,
until the desired length of the coil is obtained; the wire is then
turned back, and wound upon the first spiral, covering it, until the
other end of the coil is reached, where the winding began; then again
mounting upon the second spiral, covers it, and in the same manner
it is wound back and forth, until the required size of the coil is
attained.
[Illustration: FIG. 6.]
The coil is wound upon a form of the size (or a little larger) of the
legs of the magnet, and when the coil is completed, the form is taken
out, leaving an opening in the centre, B, into which the prongs may
freely pass. Figure 6 represents a coil constructed in the manner
described. A and A are the two ends of wire which are brought out from
the coils. The one proceeds from the centre of the coil, and the other
from the outside. C and C are circular wooden heads, on each end of
the coil, and fastened to it by binding wire, running from one head
to the other, around the coil. The wire used in constructing it, as
heretofore mentioned, is covered in the same manner as bonnet wire, and
saturated or varnished with gum shellac. This preparation is necessary,
in order to prevent a metallic contact of the wires with each other.
Such a contact of some of the wires with others encircling the iron
prong, would either weaken or altogether destroy the effect intended
by their many turns. If the wires were bare, instead of being covered,
the galvanic fluid, when applied to the two ends, A and A, instead
of passing through the whole length of the wire in the coil as its
conductor, would pass laterally through it as a mass of copper, in
the shortest direction it could take. For this reason, they require a
careful and most perfect insulation. Two coils are thus prepared for
each magnet, one for each prong, A and A, figure 5.
[Illustration: FIG. 7.]
Figure 7 exhibits a view of the magnet; figure 5, with its two coils, H
and H, placed upon the prongs. Those parts of the magnet, not concealed
by the coils, are lettered as in figure 5, and correspond with its
description. P represents the wire connecting the coil H with H, and A
and A the ends of the wires leaving the coils.
We now proceed to explain the manner by which the magnet is secured
upon a frame, and the arrangement of the armature, E, figure 7, upon
a lever, so that the motion peculiar for telegraphic writing may be
shown.
[Illustration: FIG. 8.]
Figure 8 exhibits, in perspective, a view of the electro magnet and the
pen lever, in a condition to show the effect of the galvanic battery
upon the prongs of the magnet, F and F, and the armature, D, and the
movement of the pen lever to which the electro magnet is secured. A
bolt, upon the end of which is a head or shoulder, passes through the
centre of the upright block, C, and between the coils, H and H, and
also through the brass brace, O, projecting a little beyond it, with a
screw cut upon its end. The thumb-nut, P, fitted to it, is then put on,
and the whole firmly held by screwing the thumb-nut as far as possible.
F and F are the faces of the iron prongs, as shown in figure 7,
presenting their flat surface to the armature, D. L is the pen lever,
suspended upon steel points, as its axis, which pass through its side
at X, and soldered to it. Each end of this steel centre is tapered so
as to form a sharp and delicate point or pivot. E is a screw, passing
through the side of the brass standard, G, and presenting at its end
a sunken centre, the reverse of the steel pivot point at X. There is
also another screw, similar to E, passing through the other side of the
standard at G′, with a sunken centre in its end. By the extremities
of these two screws, to which the tapered ends of the steel centre is
fitted, the pen lever is suspended, so as delicately to move up and
down, as shown by the direction of the arrow. The brass standard, G,
is secured to the upright block, C. D is the armature, soldered to
the end of the brass pen lever, L, separated from the faces of the
magnet, F and F, about the eighth of an inch. W is a yoke, secured
to the lever by a screw, and which admits through its lower part the
steel wire spring, M M, for the purpose of bringing down the lever
when not acted upon by the electro magnet. The spring is secured to a
brass standard at the top, represented by N. R represents the three
steel points of the pen,[3] which mark upon the paper the telegraphic
characters; each of which strike into its own appropriate groove in the
steel roller, S. T and T are the flanges of the steel roller, S, and
which confine the paper as it passes between the pen points, R, and the
steel roller, S, described more fully hereafter. J and I are two screws
in the horizontal cross bar attached to the standard, G, and are used
for the purpose of adjusting and limiting the pen lever in its movement
upward and downward; the one to prevent the pen points from striking
too deeply into the paper and tearing it, and the other to prevent the
armature from receding too far from the faces of the electro magnet,
and beyond its attraction, when it is a magnet. K is the connecting
wire of the two coils H and H. A and B show the ends of the wire, one
coming from each coil and passing through the stand, and seen below at
_a_ and _b_.
[3] One marking point will suffice.
Having explained this arrangement of the electro magnet, the pen lever,
and the battery; the effect of the latter upon the former will now be
described. Let one of the wires from the coils, figure 8,—_a_, for
instance, be extended so far, that it can conveniently and securely
be connected with the mercury cup, N, figure 4, of that pole of the
battery. Then take the wire _b_, figure 8, and extend it also to a
convenient length, so as to be freely handled, and connect it with the
mercury cup, P, figure 4, of the other pole of the battery. It will be
found at the instant the connection is made, that the lever, L, figure
8, will fly up in the direction of the arrow at W. The iron prongs in
the centre of the coils, H and H, which were before perfectly free
from any attractive power, have now become powerfully magnetic by the
inductive influence of the galvanic current following the circuitous
turns of the wire around the iron, so that now the electro magnet
is capable of sustaining twenty or twenty-five pounds weight. This
magnetic power concentrated in the faces of the electro magnet, F
and F, attracts to it the armature or small iron, D, drawing the pen
lever down on that side of its axis, and producing a reverse motion on
the other side at L. Now take out the wire _b_ from the mercury cup,
and in an instant its magnetism is gone, and the lever, L, falls by
the action of the spring, M. If the circuit is closed a second time,
the lever again flies up; and if immediately broken, falls. In this
manner it will continue to operate in perfect obedience to the closing
or breaking of the circuit. If the circuit is closed and broken in
rapid succession, the lever obeys and exhibits a constant and rapid
vibration. If the circuit is closed and then broken after a short
interval, the lever will remain up the same length of time, the circuit
is closed, and falls upon its being broken. Whatever may be the time
the circuit is broken, the lever will remain up for the same length
of time, and whatever may be the time it continues broken, the lever
will remain down for the same time. Suppose the magnet is separated
at the distance of one mile from the battery; upon manipulating at
the battery, at that distance, in the manner just described, the same
vibratory motion is produced in all its varieties, as when they were
removed only a short distance. Separate them 10 miles, and still the
same mysterious fluid is obedient to the pleasure of the operator in
producing the desired motion of the pen lever. If they were separated
at distances of 100 or 1000 or 100,000 miles apart, the lever would
doubtless obey the manipulations of the operator, as readily as if only
distant a few feet. Here is exhibited the principle upon which Morse’s
Electro Magnetic Telegraph is based, and which gives to the several
portions of the civilized world the power of holding instantaneous
communication with each other, with a rapidity far beyond what has
ever before been attained. As the above explanation is given only in
reference to the power of the electro magnet, when connected with the
battery, and to show the movements of the pen lever, we shall speak of
the arrangement of the wires for extended lines hereafter.
Having now explained the electro magnet and its operation through the
agency of the battery, we will proceed to describe those various parts
of the register, by which the electro magnet is made subservient to the
transmission of intelligence from one distant point to another.
Figure 9 represents, in perspective, the whole of the register, as also
the key or correspondent. The electro magnet, H and H, and the pen
lever, L, which have just been described under figure 8, need not be
recapitulated here. The letters used in figure 8, represent the same
parts of the electro magnet in this figure.
The brass frame containing the clock work, or rather wheel work, of the
instrument, is seen at 5 and 5. The whole purpose of the clock work is
to draw the paper,[4] 2, 2, under the steel roller, S, and over the
pen, R, at an uniform rate.
[4] The paper used for telegraphic writing is first manufactured by
the paper making machine in one long continuous sheet, of any length,
about three feet and a half in width, and is compactly rolled up as it
is made, upon a wooden cylinder. It is then put into a lathe and marked
off in equal divisions of one and a half inches in width; a knife is
applied to one division at a time, and as the roll of paper revolves,
the knife cuts through the entire coil until it reaches the wooden
centre. This furnishes a coil ready for the register, and is about
fifteen inches in diameter. The whole roll of paper furnishes, in this
way, about twenty-eight small rolls prepared for use.
There is also an arrangement in connection with the wheel work, by
means of which the clock work is put in motion and stopped at the
pleasure of the operator at the distant station. How this is done will
now be explained. Upon the shaft, R′, is a brass barrel, upon which is
wound the cord to which the weight, 4, is suspended, and by means of
which and the intermediate wheels, the motion produced, is communicated
to two rollers (not seen in this figure, see fig. 10, E F) in advance
of the steel grooved roller, S. These two rollers grasp the paper, 2,
2, 3, between them, and supply it to the pen at a given and uniform
rate; the rate being determined by the adjustment of the wings of the
fly, connected with the train.
[Illustration: FIG. 9.]
[Illustration: FIG. 10.]
We will now describe, by figure 10, those parts connected with the
wheel work, which could not be easily shown in figure 9. F and E
represent, in outline, the two rollers which grasp the paper, 2 and 2.
The roller E is connected with the train by a cog wheel upon it. F is
not so connected; but is pressed hard upon E by means of springs upon
the ends of the axle; S represents the grooved steel roller beneath
which the paper, 2 and 2, is seen to pass. Directly under the steel
roller is one of the steel pen points at R, upon the end of the pen
lever; a part of which only is shown. Thus far the description given of
the clock work, relates to those parts, by the agency of which the pen
is supplied with paper. We now proceed to explain that part connected
with the clock and pen lever, by which the clock is set in motion or
stopped at the option of the distant operator.
In figure 9, at R′, is seen a small pulley upon the barrel shaft of the
clock work; at Q, is another pulley, but larger. From the pulley, R′,
is a cord,[5] or band, 10, proceeding to pulley, Q, and then returning
under it to pulley, R′, making it continuous. This band communicates
the motion of pulley, R′, to the pulley, Q. In figure 10, these pulleys
are represented by the same letters. B represents the barrel; the
arrow, the direction in which it revolves when in motion. The arrow at
Q shows the direction which it takes when motion is communicated to it
by R′. Part of the pulley, Q, is broken away in order to show the arm,
H, soldered at the middle of the same spindle upon which is the pulley,
Q, and directly beneath the pen lever, L. It is bent at D, so as to
turn down and strike the wooden friction wheel, C, at the point, P. The
friction wheel is secured upon the last spindle of the train at its
middle and directly under the lever, L. From the pen lever, L, is seen
a small rod of wire, A, passing down through the arm, H, with screw and
nut under it, at I, for the purpose of shortening or lengthening it. It
is permitted to work free, both at its connection with the lever and
arm. This wire is also extended and passes down through the platform,
where it operates upon a hammer for striking a bell, to apprise the
operator that a communication is to be sent. The several parts being
now explained, their combined action is as follows:
[5] The pulley and cord have been dispensed with and two small cog
wheels substituted.
The arm, H and D, is a break, which when brought in contact with the
friction wheel, C, prevents the weight of the clock work from acting
upon the train, and there is no motion. By the action of the magnet,
the pen lever, L, is carried up in the direction of the arrow, 3, and
takes with it the connecting rod, A, and also the break, H, D. The
break being thus removed from the friction wheel, C, the clock work
commences running by the power of the weight. The barrel, B, must
consequently turn in the direction of the arrow upon it; this motion
is communicated by the band to Q, which revolves in the direction of
its arrow; consequently, if the lever, L, is not still held up by the
magnet, the break is descending slowly; and when it reaches P, stops
the motion of the clock train, unless the pen lever continues in
motion, in which case the break, D, is kept up from the friction wheel,
thus permitting the clock work to run, until the lever ceases to move,
when the break is gradually brought down upon the friction wheel, and
the train stops. By this contrivance, the operator at a distance can so
control the movement of the paper at the remote register, that when he
wishes to write, it shall be put in motion, his pen be supplied with
paper, and when he has finished his writing, the register shall stop.
U represents (figure 9) the brass standards, one on each side of the
large roll of paper, 1, 1, 1, which it supports. Z is a wooden hub,
upon which the roll is placed; and 12, the steel arbor of the hub, and
upon which the whole easily revolves as the paper, 2 and 2, is drawn
off by the clock work. Y is a brass spring, between the hub and the
standard; and keeps the paper stretched between the roll and the pen.
[Illustration: FIG. 11.]
The key or correspondent is represented by 6, 7, 8, 9. Another view
of it is more distinctly seen in figure 11. The same letters in each,
represent the same thing. V and V is the platform. 8 is a metallic
anvil, with its smaller end appearing below, to which is soldered the
copper wire _c_. 7 is the metallic hammer, attached to a brass spring,
9, which is secured to a block, 6, and the whole to the platform, V V,
by screws. A copper wire passes through the whole, and is soldered to
the brass spring at 6. The key or correspondent is used for writing
upon the register at the distant station, and both it and the register
are usually upon the same table.
Having now explained the Register, Key and Battery, we proceed to
describe the arrangement of the conductors or wires connecting distant
stations, and the mode by which the earth, also, is made a conductor of
this subtle fluid.
The term _circuit_ used frequently in this work, has reference to the
wire, which, commencing at the positive pole of the battery, goes to
any distance and returns to the negative pole of the battery. When its
going and returning are continuous or unbroken, the circuit is said
to be _closed_ or _complete_. When it is interrupted, or the wire is
disconnected, the circuit is said to be _broken_ or _open_.
When a magnet or key or battery is spoken of as being _in the circuit_,
it has reference to the use of the wire belonging to the key, magnet or
battery, respectively, as a part of the circuit.
There are three modes of arranging the wires, so as to communicate
between two distant stations. Two of these modes are _inferior_, as
they furnish but one circuit for the termini, and consequently obliging
one station to wait, when the other is transmitting, both stations not
being able to telegraph at the same time. These two modes are called
the _dependent circuits_. The first mode is, where two wires are
used, of which figure 12 is a diagram. B represents Baltimore, and W
Washington; _m_ is the magnet or register; _k_ the key, and _bat_ the
battery, all at the Baltimore station; _m′_ is the magnet or register;
_k′_ the key at the Washington station. The lines, represent the wires
upon the poles, connecting the two stations, and are called the east
and west wires. In this arrangement of the wires and also in the
second, the key (which has been explained in a preceding figure, 11,
and shown at 6 and 7 to be open) must be closed at both stations, in
order to complete the circuit, except at the time when a communication
is being transmitted.[6] For the purpose of closing the circuit at the
key, a metallic wedge is used, which is put in between the anvil 8 and
the hammer 7, and establishes the circuit. Supposing the battery is in
action, and B has a communication for W: he opens his key, by removing
the wedge, and sends his message. The galvanic fluid leaves the point,
P, of the battery, and goes to _k_, to _m_, along the east wire to
_k′_, to _m′_, and back by the west wire to N pole of the battery. In
the same manner it proceeds along the wires, if W is writing to B. In
this arrangement, the direction of the galvanic current is the same,
whether B or W is communicating, unless the poles of the battery are
reversed.
[6] At this time the key is opened at the station from which the
communication is to be sent.
[Illustration: FIG. 12.]
[Illustration: FIG. 13.]
The second mode has but one wire and the ground, represented by figure
13. The use of the ground as a conductor of the galvanic fluid, between
two distant points, is to many a mystery. But of the fact there is no
question. The above diagram exhibits the manner in which the east wire
and ground were used from the first operation of the Telegraph, until
the close of the session of Congress, June, 1844. In this diagram, we
will minutely follow the course of the galvanic current. B represents
Baltimore, and W Washington; C represents a sheet of copper, five feet
long and two and a half feet wide, to which a wire is soldered and
connects with the N pole of the battery. This sheet of copper lies in
the water at the bottom of the dock, near the depot of the Baltimore
and Ohio Rail Road, Pratt street. From P of the battery, the wire
proceeds to _k_, the key, then to _m_, the magnet or register, then
it is the _east wire_ to _k′_, the key at W, then to _m′_, the magnet
or register, then to the _copper sheet_, C′, buried beneath the brick
pavement in the dry dust of the cellar of the capitol. The direction
of the current is from P of the battery to _k_, to _m_, and along the
east wire to _k′_, to _m′_, and to C′, where it is lost in the earth;
but reappears at the copper plate, C, at B, and thence to the N pole of
the battery, having completed its circuit. It is, therefore, certain,
that one-half of the circuit is through the earth. From B to W the east
wire is the conductor; and from W to B the ground is the conductor. In
this arrangement, the west wire is thrown out, and is no part of the
circuit; while the earth has been made a substitute for it.
[Illustration: FIG. 14.]
The last diagram, as has been stated, exhibits the plan of the
wire and ground, as used for telegraphic purposes, from its first
operation, until the adjournment of Congress in 1844, being prevented
from completing the arrangement of the third mode from the throng of
visitors, that pressed to see its operation. After the close of the
session, the following arrangement of the wires was made, as shown
in the diagram, figure 14, by means of which, both stations could
transmit at the same time, with one battery for both, and the keys
were not required to be closed. It is called the two _independent
circuits_. Here the west wire is used for transmitting from B to W;
and the east wire from W to B. The copper plates at B and W remain
as they are described in the second plan. _Bat_, the battery, at B
is used in common for both circuits. It is simply necessary here to
designate the course which the fluid takes when both lines are in
operation, viz. B transmitting to W; and W to B. In the former case,
the current is from P of the battery to _k_, then the _west wire_,
then to _m′_, at W, then to _C′_, thence through the ground to _C_ at
B, and then to the N, or negative pole of the battery, as shown by the
arrows. In the latter case, the current is from P of the battery to
_m_, then the _east wire_, then to _k′_, at W, thence to _C′_, thence
through the ground to C at B, thence to the N, or north pole of the
battery, as shown by the arrows. This arrangement, by which one battery
is made efficient for both circuits at the same time, where two were
formerly used, was devised by Mr. Vail, assistant superintendent, in
the spring of 1844, and has contributed much to diminish the care and
expense in maintaining that part of the apparatus of the telegraph. One
battery being now used instead of two. By the above diagram, it will
be perceived that the _ground_ is common to both circuits, as well as
the _battery_, and also the wire from the N pole of the battery, to
the copper plate, C; and from the copper plate, C′, to the junction
of the two wires near the two arrows. For the purposes of telegraphic
communication they answer as well as though there were four wires
and two batteries. Instead of using the ground between C and C′, a
wire might be substituted, extending from the N pole of the battery
to the junction of the wires at the two arrows at W. The arrangement
of the wires, battery, keys, magnets or registers at both stations,
with the ground, as shown in figure 14, is the plan now used for
telegraphic operations between B and W; and has many decided advantages
over the arrangements of figures 13 and 14. First. In both of those
arrangements, the circuit is obliged to be kept closed, when neither
station is at work; and as the battery is only in action when the
circuit is closed, it follows that the battery will not keep in action
as long as when the circuit is allowed to remain open, as in the use of
the third plan, figure 15. Second. There is an advantage in dispensing
with the use of the metallic wedge, which is liable to be forgotten by
the operator. Third. The attendant may occasionally leave the room, and
is not required to be in constant waiting, as the clock work is put in
motion and stopped by the operator at the other end, and the message
written without his presence. But in the first and second arrangement,
the apparatus for putting in motion and stopping the clock work, is
entirely useless. The attendant being obliged to put it in motion and
stop it himself.
We will now proceed to describe the modus operandi of transmitting
intelligence from one station to another; the arrangement being as
in figure 14; _k_ is the key of the operator at Baltimore, and _m′_
represents his register, or writing desk, at Washington; _k′_ is the
key of the operator at Washington, and _m_ his register, or writing
desk, at Baltimore. Each has the entire control of his respective
register, excepting, only, that each operator winds up the other’s
instrument, and keeps it supplied with paper. It will also be borne
in mind, that each circuit is complete, and everywhere continuous,
except at the keys, which are open. If, then, the hammer is brought in
sudden contact with the anvil, and permitted as quickly as possible to
break its contact by the action of the spring, and resume its former
position, the galvanic fluid, generated at the battery, flies its round
upon the circuit, no matter how quick that contact has been made and
broken. It has made the iron of the electro magnet a magnet; which
has attracted to it the armature of the pen lever; the pen lever, by
its steel pen points, has indented the paper, and the pen lever has,
also, by the connecting wire with the break; taken it from the friction
wheel; this has released the clock work, which, through the agency of
the weight, has commenced running, and the two rollers have supplied
the pen with paper. But, as only one touch of the key has been made,
the clock work soon stops again, if no other touches are made, by the
action of the break upon the friction wheel.
This shows the whole operation of the Telegraph, in making a single dot
by a single touch of the key. In order now to explain more fully the
operation of the steel pen points upon the paper, which is in contact
with the grooved roller, let there be made four touches at the key;
this will be sufficient to start the clock work, and allow the paper to
have attained a uniform rate; then let six touches be made at the key.
The contact has been made six times and broken six times. Each time it
is closed, the electro magnet, as heretofore explained, attracts to
it, with considerable force, the armature of the pen lever, carrying
up the steel pen points against the paper, 2, under the steel roller,
S. The three points of the pen, falling into the three corresponding
grooves of the roller, carry the paper with them and indent it,[7]
at each contact. There then appear upon the paper, as it passes out
from under the rollers, six indentations, as if it had been pressed
upon by a blunted point, such as the end of a knitting needle would be
supposed to make, when pressed upon paper, placed over a shallow hole,
but in such a manner as not to pass through the paper, but raising the
surface, as in the printing for the blind. These indentations of the
paper are the marking of the pen, but varied in the manner now to be
described.
[7] The first working model of the Telegraph was furnished with a
lead pencil, for writing its characters upon paper. This was found to
require too much attention, as it needed frequent sharpening, and in
other respects was found inferior to a pen of peculiar construction,
which was afterwards substituted. This pen was supplied with ink from
a reservoir attached to it. It answered well, so long as care was
taken to keep up a proper supply of ink, which, from the character of
the letters, and sometimes the rapid, and at others the slow rate of
writing, was found to be difficult and troublesome. And then again,
if the pen ceased writing for a little time, the ink evaporated and
left a sediment in the pen, requiring it to be cleaned, before it was
again in writing order. These difficulties turned the attention of the
inventor to other modes of writing, differing from the two previous
modes. A variety of experiments were made, and among them, one upon
the principle of the manifold letter writers; and which answered
the purpose very well, for a short time. This plan was also found
objectionable, and after much time and expense expended upon it, it was
thrown aside for the present mode of marking the telegraphic letter.
This mode has been found to answer in every respect all that could be
desired. It produces an impression upon the paper, not to be mistaken.
It is clean, and the points making the impression being of the very
hardest steel, do not wear, and renders the writing apparatus always
ready for use.
By examining the telegraphic alphabet, the characters will be found to
be made up of dots: short and long lines—and short and long spaces.
A single touch of the key, answers to a single dot on the paper of
the register; which represents the letter, E. One touch of the key
prolonged, that is, the contact at the key continued for about the
time required to make two dots, produces a short line, and represents
T. A single touch for about the time required to make four dots, is
a long line, and represents L. A single touch for about the time
required to make six dots, is a still longer line and represents the
0 of the numerals. If the use of the key be suspended for about the
time required to make three dots, it is a short space, used between
letters. If suspended for the time required to make six dots, it is a
long space, used between words, and a longer space is that used between
sentences. These are the elements which enter into the construction of
the telegraphic characters, as used in transmitting intelligence. The
alphabet is represented by the following combination of these elements.
ALPHABET.
·- -··· ·· · -·· · ·-· --· ···· ·· -·-· -·-
A B C D E F G H I J K
—— -- -· · · ····· ··-· · ·· ··· - ··- ···-
L M N O P Q R S T U V
·-- ·-·· ·· ·· ··· · · ··· ·--· ··-·· ···-· ····-
W X Y Z & 1 2 3 4
--- ······ --·· -···· -··- ———
5 6 7 8 9 0
Suppose the following sentence is to be transmitted from Washington to
Baltimore:
- ···· · ·- -- · · ·· ·· ·· · ·- -· · —— · ·· ·
T h e A m e r i c a n E l e c
- · ·· · · -- ·- --· -· · - ·· ·· · - · —— · --·
t r o M a g n e t i c T e l e g
· ·· ·- ····· ···· ·· -· ···- · -· - · -·· -··· ·· ··
r a p h i n v e n t e d b y
····· · ·· · · ·-· · ··· ··· · · · ·· ··· ·-· -··· -- · ·
P r o f e s s o r S F B M o
· ·· ··· · · · ·-· -· · ·-- ·· ·· · · · ·· -·-
r s e o f N e w Y o r k
· · -· -··· · · ·- · ·· -·· · · ·-· - ···· ·
o n b o a r d o f t h e
····· ·- ·· · -·- · - ··· ···· ·· ····· ··· ··- ——
p a c k e t s h i p S u l
—— ·· ·· ·· · ·- ····· - ····· · —— —— · · -·
l y C a p t P e l l o n
···· · · ·· ····· ·- ··· ··· ·- --· · ·-· · ·· · · --
h e r p a s s a g e f r o m
···· ·- ···- · ·· · - · · -· · ·-- ·· ·· · · · ··
H a v r e t o N e w Y o r
-·- · · ·· · - · · -··· · · ·· ·--· -···· ···-· ··-··
k O c t o b e r 1 8 3 2
It is evident, as the attendant at Baltimore has no agency in the
transmission of this message from Washington, his presence, even, is
not absolutely required in the telegraph room at Baltimore, nor is
it necessary, previously, to ask the question, _are you there_? The
operator at Washington transmits it to Baltimore, whether the attendant
is there or not, and the telegraphic characters are distinctly recorded
upon the paper of the Baltimore-register. If he omits a letter at the
key, in Washington, it is omitted on the paper in Baltimore. If he has
added at the key in Washington, it is also upon the paper in Baltimore,
nothing more or less is marked upon it.
_Specimen of the Telegraphic Language._
·· -· - ···· · ·· ·· · ·- · ·· ·--· -···· ···-·
··-·· · · -· -- ·· ·· ···- · · ·· ·· ·- --· · ····
· · -- ·· ·-· · ·· · · -- · ··- · ·· · · ····· · -
···· · · —— · ·· · - · ·· ·· ·· · ·- —— · ·-··
····· · · ·· ·· -- · -· - · · ·-· ·-· · ·· ·- -· -·-
—— ·· -· ··- ····· · · -· ·- ·-- ·· · ·· · ···
· · -- · ····- -- ·· —— · ··· ·· -· —— · -· --·
- ···· ·-- ·- ··· ·· · ·- ··· ··- ·- —— —— ·· ··
· ·· · ·· · ·- —— —— · -·· - · · -- ·· ·· -- ·
-· -·· ·· -· ·- ·· · · · -· ···- · · ·· ··· ·- -
·· · · -· ·-- ·· - ···· ·--· · · ·-· - ···· ·
····· ·- ··· ··· · -· --· · · ·· ··· ·· -· ·-- ····
·· ·· · ···· · ·-·· ····· · · ·· ·· -- · -· - ·· -
·-- ·- ··· ·- ··· ·· · · · ·· - ·- ·· -· · -·· -
···· ·- - - ···· · · —— · ·· · - · ·· ·· ·· · ··
- ·· ·· - · ·· ·- ···- · —— —— · -·· - ···· · ··
· · ··- --· ···· - ···· · ·-- ···· · · —— · ·· ·
·· · ·· ·· · ··- ·· - ·· -· ·- - ·· -- · -·
· · - ·- ····· ····· · ·· · ·· · ·· ·- -··· —— · -···
··- - ·- ····· ····· ·- · ·· · -· - —— ·· ·· ·· -·
··· - ·- -· - ·- -· · · · ··- ··· ·· - ·· -- -- ·
-·· ·· ·- - · —— ·· ·· · · ·· · ·· · ··- · ·· · ·· ·
-·· - · · -- · - ···· ·- - ·· ·-· - ···· ·
····· · ·· · ··· · -· ·· · · · · ·-· · —— · ·· · -
· ·· ·· ·· · ·· - ·· ·· ·· · · · ··- —— -·· -··· ·
-- ·- -·· · ···- ·· ··· ·· -··· —— · ·· -· ·- -·
·· ·· -·· · ··· ·· · ·· · -·· ····· ·- · ·· - · ·
·-· - ···· ·· ··· ·· · ·· · ·· ·· · ··- ·· - ·· -
·-- · · ··- —— -·· -· · · - -··· · -·· ·· ·-· ·-·
·· ·· · ··- —— - - · · ·· · · · -· ··· - · ·· ··-
·· · - ·- ··· ·· ·· ··· - · -- · · ·-· ··· ··
--· -· ··· -··· ·· ·· ·-- ···· ·· ·· · ···· ·· -·
- · —— —— ·· --· · -· ·· · · ·· · · · ··- —— -··
-··· · ·· -· ··· - ·- -· - ·- -· · · · ··- ··· ——
·· ·· - · ·· ·- -· ··· -- ·· - - · -·· - ···· ·
- ···· · · ··- --· ···· - - ···· ··- ··· ·· · · · -·
·· · · ·· ···- · -·· - · · · · -·- ··· - · ·· · ·
-· --· ···· · · —— -·· · · ·-· -- ·· ·· -- ··
-· -·· ·· -· - ···· · —— · ·· ··· ··- · ··· ·--
···· ·· ·· · ···· - ···· · ···- · · ·· ·· ·- --· ·
·- ·-· ·-· · · · ·· -·· · -·· · ··· ·· ····· ——
·- -· -· · -·· ·- ··· ·· ·· ··· - · -- · · ·-·
··· ·· --· -· ··· · ··· ·- -· ·- ····· ····· ·- · ··
·- - ··- ··· - · · ·· · ·- · ·· · ·· ·· ·· ·· - ··
-· - · · · ·-· ·-· · ·· · - ·· ·· · ·- ··· - ·-
··· ····· · ·· · ·· · ··· · · ·-· - ·· ·· ····· ·
·-- ···· ·· ·· · ···· ·· ···· ·- -·· -·· · ···- ··
··· · -·· ·-· · · · ·· - ···· ·· ··· ····· ··-
· ·· ····· · · ··· · - ···· · ·-· ·· · ·· ··· -
·-- · · -·- ·- ·-· - · · ·· -- ·· ·· ·- · ·· · ··
·· ···- ·- —— ···· · · -- · · ··· ·- —— - ····
· · ··- --· ···· - ···· · · ·· · ··· - · · ·-· -
···· · -- ·- ·· · ···· ·· -· · · ·· ·· ·· ·-- ·- ···
····· —— ·- -· -· · -·· ·· ·· · - ·-· · ·· · · --
- ···· · ····· · ·· · ··· ··· ··- · ·· · · · ·-· ··-
-· ·- ···- · · ·· -·· ·- -··· —— · -·· ··- - ·· ·
··· ·· ·-- ·- ··· ·· · · · -- ····· · —— —— ·
-·· - · · ····· · · ··· - ····· · · -· · -- ·· ··
· ·-·· ····· · · ·· ·· -- · -· - ··· · ··· ·-- ·-
··· -· · · - ·- -··· —— · - · · - · ··· - -
···· · ·-- ···· · · —— · ····· —— ·- -· ··- -·
- ·· —— ·-- ·· - ···· ·· -· ·- ·-· · ·-- ·-- · ·
-·- ···
··· ·-· -··· -- · · · ·· ··· ·
From the peculiarity of the motion obtained at the pen lever by the
action of the battery upon the electro magnet, it is evident that a
few elements only are presented upon which to base the telegraphic
characters. The motion of the lever, to which is attached the steel pen
points, is vibratory; but capable of being so controlled as to cause
it to retain either of its positions (that is, up or down) as long,
and at such intervals, and in as quick succession as the operator may
choose. Therefore, every sort of combination which dots, lines and
spaces, in any succession, and of any length can make, are here as much
at the pleasure of the telegraphic manipulator, as the English alphabet
is with the letter writer. So that if from this countless variety,
twenty-six of the most simple, to represent letters, and ten to
represent the numerals, shall be taken, we come at once into possession
of the means of representing words and sentences, by new, but
intelligible characters, and through them, can be conveyed as clearly,
and as concisely, as if they were given viva voce, or written in
Roman characters. Such is the alphabet given above. This conventional
alphabet was originated on board the packet Sully, by Prof. Morse, the
very first elements of the invention, and arose from the necessity of
the case; the motion produced by the magnet being limited to a single
action.
During the period of thirteen years, many plans have been devised by
the inventor to bring the telegraphic alphabet to its simplest form.
The plan of using the common letters of the alphabet, twenty-six in
number, with twenty-six wires, one wire to each letter, has received
its due share of his time and thought. Other modes of using the common
letters of the alphabet, with a single wire, has also been under his
consideration. Plans of using two, three, four, five and six wires to
one registering machine, have, in their turn, received proportionate
study and deliberation. But these, and many other plans, after much
care and many experiments, have been discarded; he being satisfied that
they do not possess that essential element, _simplicity_, which belongs
to his original first thought, and the one which he has adopted. A
detailed account of these various plans with fewer or more wires, might
be given here, but it will suffice merely to present the alphabet
adapted to a register, using 2, 3, 4, 5, or 6 wires, with a separate
pen to each wire capable of working together, or in any succession. It
is obvious that every additional pen will give an additional element to
increase the combination, and were there any real advantage in such an
arrangement it would have been adopted long since.
No. 1.
_Alphabet for two pens, operating together or in succession._
· · · · ·· ·· · · ·· -- -- · · -- --
· · · · · · ·· ·· ·· -- -- -- -- · ·
A B C D E F G H I J K L M N O P Q
-- ·· --· ·-- --· ·-- · · --· ·-- · ·
·· -- --· ·-- · · ·-- --· · · --· ·--
R S T U V W X Y Z & 1 2 3 4
·-- --· --· ·-- -- --
·-- --· -- -- --· ·--
5 6 7 8 9 0
No. 2.
_Alphabet for three pens, operating together or in succession._
· · · · ·· ·· ·· · · ·
· · · · ·· · ·· ·· · · ·· ·· · ··
· · · · ·· · · ·· ·· ·
A B C D E F G H I J K L M N O P Q R S
· ·· ·· ·· ·· · · · · ·· ·· ·· ·· ·· ·· ·
·· ·· ·· · · · · · · ·· ·· ··
· ·· ·· · ·· ·· ·· ·· · · ·· ·· · · ··
T U V W X Y Z & 1 2 3 4 5 6 7 8 9
·
··
··
0
No. 3.
_Alphabet for four pens, operating together or in succession._
· · · · · · · · ·· ··
· · · · · · · · · ·· ··
· · · · · · · · · ·· ·· ·
· · · · · · · · · · ·
A B C D E F G H I J K L M N O P Q R S T U
·· · · ·· ·· ··
· ·· · · ·· ·· ·· ·· ··
·· · · ·· ·· ·· ·· ··
·· ·· ·· ·· ··
V W X Y Z & 1 2 3 4 5 6 7 8 9 0
No. 4.
_Alphabet for five pens, operating together or in succession._
· · · · · · · ·
· · · · · · · · · ·
· · · · · · · · · · ·
· · · · · · · · · ·
· · · · · · · ·
A B C D E F G H I J K L M N O P Q R S T U
· · · · · · · ··
· · · · · ··
· · · · · ·· ·
· · · · · ·· · ··
· · · · · · · ·· ··
V W X Y Z & 1 2 3 4 5 6 7 8 9 0
No. 5.
_Alphabet for six pens, operating together or in succession._
· · · · · · ·
· · · · · · · · · · ·
· · · · · · · · · · · · · ·
· · · · · · · · · · · · ·
· · · · · · · · · · ·
· · · · · · · · · ·
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
· · · · · · ·
· · · · ·
· · · ·
· · · · ·
· · · ·
· · · · · ·
& 1 2 3 4 5 6 7 8 9 0
CORRESPONDENT OR KEY.
The modes of manipulation for sending intelligence, which at various
times have been invented by Prof. Morse, are more various than any
other part of the machinery of the telegraph. A few of them will now
be described. The first method, invented as early as the year 1832,
was that of using a type, resembling saw-teeth, set up in long frames,
and made to pass under a lever, by means of machinery, at a uniform
rate, for the purpose of closing and breaking the circuit, in a manner
hereafter to be described. The following figure, 15, represents the
saw-teeth type. The top of the narrow tooth corresponds with the _dots_
of the letters, and the long tooth, with the _lines_ of the letters.
For instance, A, has one tooth for a dot, and a long tooth for a line,
which is the telegraphic letter A; then follows a space at the end of
the type, corresponding with the short space between two letters.
[Illustration: FIG. 15.]
[Illustration: FIG. 16.]
These type were set up in a cavity, made by putting two pieces of
long rules of brass plate together, side by side, with a strip of
half their width between them; so as to make the cavity sufficiently
large to receive the type. This was denominated the _port rule_, and
is represented in figure 16 by A A. Parts of the type are seen rising
above the edge of the _rule_, and below it are seen the cogs, by
which, with the wheel, V, the pinion, L, and the crank, O, the port
rule, with its type, were carried along at an uniform rate in a groove
of the frame, K, R, under the short lever, C, which has a tooth, or
cam, at its extremity. J is a support, one on each side of the frame,
for the axis of the lever, B and C, at its axis, I; _a_ and _i_ are
two brass or copper mercury cups, fastened to the frame. These cups
have the negative and positive wires soldered to them, N and P. D and
H are the ends of _one_ copper wire, bent at right angles at that
portion of it fastened to the lever, B. The ends of the copper wire are
amalgamated, and so adjusted, that when the lever is raised at C, by
the action of its cam, passing over the teeth of the type, the lever,
B, is depressed, and the wires, D and H, dip into the mercury cups,
and thus complete the connection. This plan worked well, but was too
inconvenient and unwieldy.
The second method was upon the same principle, with a more compact
arrangement. The type being put into a hopper and carried one by one
upon the periphery of a wheel, the teeth acting upon a lever in the
same manner as in the figure preceding. The wheel being horizontal.
[Illustration: FIG. 17.]
The third plan differed only in one respect, instead of the types
moving in a circle, they were made to move in a straight line. Figure
17 represents that instrument. The type were all made with small
holes through their sides, so as to correspond with the teeth of the
wheel, A, driven by clock work and weight. K is the side of the frame
containing the clock work. B is the hopper containing the types, with
their teeth outward. The hopper is inclined at an angle, so that the
type may slide down as fast as one is carried through the cavity, _a_
and _b_. C is a brass block to keep the type upright, and sliding down
with them. E and F are two small rollers, with springs (not shown)
to sustain the type, after the wheel, A, has carried them beyond its
reach. G is a lever for the same purpose as C in figure 16. D its
support, through which its axis passes. I′ is the long lever, O, of the
left side figure, to the end of which, is the bent wire in the mercury
cups, H and S, and to which are soldered the wires, P and N. T is the
spring to carry back the lever, O. F′ is one of the small rollers, and
G′ the short lever. At R may be seen a part of one of the type passing;
the tooth having the short lever upon its point, thereby connecting
the circuit at the mercury cups, H and S, by the depression of the
long lever, O. The hopper, B, may be of considerable length, and at a
less angle. When a communication is to be sent, it is set up in type,
and put in the hopper. The clock work is then put in motion, and the
wheel, A, will carry them down one by one. In this manner, the cam on
the end of the lever, G, will pass over all the teeth of the type, as
in the plan shown by figure 16.
The fourth plan was by means of keys, one for each letter and numeral.
By pressing upon any one of the keys, it wound up the clock work of the
instrument. The key being instantly released, and returning gradually
to its former position, produced the closing and breaking of the
circuit required to write its character upon the register.
The fifth plan is in some respects similar to the last, but much more
simple, and requiring less time in transmitting intelligence. Figure
18 exhibits a view of the keyed correspondent, with its clock work. A′
represents a top view of it, and B′ is a side or front view. 1 1 1 1,
of both views, represent the long cylinders of sheet brass, covered
with wood or some insulating substance, except at the black lines,
which represent the form of the letters, made of brass, appearing at
the surface of the cylinder and extending down and soldered to the
interior brass cylinder. A cross section of the cylinder is seen at D′,
of which the blank ring is the brass cylinder, and the blank openings
to the outer circle the metallic forms of the letter J, and the shaded
portion of the circle represents the insulating substance, covering
the whole surface of the cylinder, except, where the letter-forms
project from the interior. It is obvious that every letter and parts
of each letter are in metallic connection with the brass cylinder. At
each end of the cylinder is a brass head, with its metallic journal,
and the journal or arbor turns upon its centre in a brass standard,
17, secured to the vertical frame. To this standard is soldered the
copper wire, N, connected with the negative pole of the battery. There
are together thirty-seven letters and numerals upon the cylinder,
and made to correspond to the letters of the telegraphic alphabet.
To each of these, there is a separate key, directly over the letter
cylinder. Each key has its button, with its letter, A, B, C, D, &c.,
marked upon it, and beneath the button in a frame of brass, is a little
friction roller. The key is a slip of thin brass, so as to give it
the elasticity of a spring, and is secured at the thicker end by two
screws to a brass plate, extending the whole length of the cylinder,
so as to embrace the whole number of keys. This plate is also fastened
to the vertical mahogany frame. At the right hand end of the brass
plate is soldered a copper wire, leading to the positive pole of the
battery, after having made its required circuit through the coils of
the magnet, &c. It is clear, that if any one of the keys is pressed
down upon any portion of a metallic letter, that the circuit is
completed; the galvanic fluid will pass to the brass plate to which,
P, wire is soldered; thence along the plate to the spring or key; then
to the small friction roller beneath the button; then to that portion
of any letter with which it is in contact; then to the interior brass
cylinder, to the arbor; then to the brass standard, and along the
negative wire, soldered to it, to the battery. We have now to explain
in what manner, the cylinder is made to revolve, at the instant any
particular key is pressed, so that the metallic form of the letter
may pass at an uniform rate under the roller of the key; breaking and
connecting the circuit so as to write at the register, with mechanical
accuracy, the letter intended.
[Illustration: FIG. 18.]
[Illustration]
[Illustration: FIG. 19.]
4 4 is the platform upon which the parts of the instrument are
fastened. 3 3 is the vertical wooden back, or support, for the keys
and brass standard, 17. 2 is the barrel of the clock work contained
within the frames, 5 5. With the clock work, a fly is connected for
regulating its motion, and a stop, a, for holding the fly, when the
instrument is not in use; 6 is a very fine tooth wheel, on the end of
the letter cylinder; 7 is also a fine tooth wheel, on a shaft driven by
the clock train. In the front view is seen, at 9, another fine tooth
wheel, suspended upon a lever, the end of which lever is seen at 8,
figure 18, A′. 18 is a stop, in the standard, 17, to limit the return
motion of the cylinder, which also has a pin at 18, at right angles
with the former. 16 is a small weight, attached to a cord, and at its
other end, is fastened to the cylinder at _b_. The relative position
of the three fine tooth wheels, and the lever, 8, are better seen in a
section of the instrument, figure 19. The same figures represent the
same wheels as in the other views, A′ and B′. 7 is the wheel driven
by the weight and train. 6 the wheel, on the end of the cylinder, to
which motion is to be communicated, and 9 is the wheel, suspended upon
the end of the lever, 8, of which 10 is its centre. 1 1, is the brass
lettered cylinder. 11 and 13 the buttons of the two keys, one a little
in advance of the other. 14 is the spring and the two friction rollers
of the key, may be seen directly under the buttons. 15 is the stop pin.
16 the small weight and cord attached to the cylinder, to bring it back
after each operation. 4 4 is the end view of the mahogany platform.
The arrows show the direction which the wheels take, when the lever is
pressed with the thumb of the left hand at 8, so as to bring wheel 9,
up against 7 and 6, connecting the two, as shown by the dotted lines.
Wheel, 7, communicating its motion to 9, and 9 to 6, which causes the
metallic letters to pass under the rollers in the direction of the
arrow. Now, in order to use the instrument, let it be supposed a letter
is to be sent. The stop, _a_, figure 18, A′, is removed from the fly,
and the clock work is set in motion by the large weight. Then the
thumb of the left hand presses upon the _lever_, 8, at the same time,
_key_, _R_, is pressed down by the finger of the right hand, so that
the small roller comes in contact with the cylinder. At the instant
the roller touches the cylinder, the letter begins to move under the
small roller, making and breaking the circuit with mechanical accuracy.
When the letter has passed under the small roller, the thumb is taken
off the lever, 8, and the finger from the key, R. The cylinder is then
detached from its gear wheel, 9, and the weight, 16, instantly carries
it back to its former position, in readiness for the next letter.
Then the _lever_, 8, and the _key_, _E_, are pressed down at the same
instant for the next letter, and it is carried under the small roller
in the same manner as the first, which, when finished, the wheel, 9,
is suffered to fall, and the cylinder returns to its natural position
again. The same manipulation is repeated for the remaining letters of
the word.
In the following figure, 20, is represented the flat correspondent. It
somewhat resembles the keyed correspondent, but without keys or clock
work. A represents the arrangement of the letters, presenting a flat
surface. Those portions in the figure, marked by black lines and dots,
represent the letters which are made of brass. That portion which is
blank, represents ivory or some hard insulating substance, surrounding
the metal of the letters. As in the keyed correspondent, each letter
and parts of each letter extend below the ivory and are soldered to a
brass plate, the size of the whole figure, A. A sectional view of this
is seen at 1 1, which is ivory, and 2 2, the brass plate below. The
whole is fastened to a table, B. 5′ and 5′ is a brass plate, called the
guide plate, with long openings, represented by the blanks, so that
when the guide plate, 5′ 5′, is put over the form, A, each opening is
directly over its appropriate letter, and is a little longer than the
length of the letter. 4′ and 4′ is the wooden frame, to which the guide
plate is secured. The ends of this frame are seen in the sectional
figure at 4 4, and the guide plate at 5 5. The dark portions of which,
represent the partitions, and the blanks the openings. It will be
observed here that the plate, 5 5, resting upon the wooden frame 4
4, is completely insulated from the brass letter plate 1 1, and 2 2.
The blank space between them showing the separation. It is, however,
necessary that the guide plate should be connected with one pole of the
battery, and the letter plate with the other pole. For this purpose a
brass screw, F, passes up through the table, B, and through 4, into the
guide plate 5 5. The head of the screw has a small hole through it,
for passing in the end of the copper wire, G, from the battery, and a
tightening screw below, by which a perfect connection is made. At D, is
another screw, passing through the table, and into the letter plate, 2
2. To the head of this screw is also connected another copper wire, E,
extending to one of the poles of the battery.
[Illustration: FIG. 20.]
This instrument, when used, occupies the place of the key or
correspondent, in the description heretofore given of the register.
The circuit is now supposed to be complete, except, between the guide
plate, 5 5, and the letter plate, 2 2. Now, if a metallic rod, or
pencil, C, be taken, and the small end passed through one of the
openings in the shield, above the letter, its point will rest upon the
ivory; and if it be gently pressed laterally against the side of the
opening of the guide plate, at the same time a gentle pressure is given
to it upon the ivory, and then drawn in the direction of the arrow,
4′, it is obvious, that when the metallic point reaches, for instance,
the short line of letter B, the circuit will be closed; and the fluid
will pass from the battery along the wire to the screw, F, then to
the guide plate, along the plate, to the rod, thence to the metallic
short line of letter B, thence to the letter plate below, thence to the
screw, from the screw to the wire, and thence to the battery. When the
point has passed over the short metallic line, it reaches the ivory,
and the circuit is broken, then, when it comes upon the first metallic
dot, it is again completed, and in the same manner the circuit will be
completed and broken, until the point has passed over the whole of the
letter. The use of this instrument requires great uniformity of time or
speed in drawing the point over the letter form. The steel point of a
common ever-pointed pencil is frequently used in place of the pointed
rod, C.
The seventh plan is that heretofore explained as being now in use,
of which there are several varieties. This mode of writing requires
that the operator should be perfectly familiar with the alphabet, as
he is obliged to spell the word, and measure the time, required by
the various parts of each character making the letter. It might seem
difficult, yet experience has proved it to be superior to every other
method yet devised. By this method, intelligence is transmitted faster
than it can be written down by reporters; and after a little practice,
with so perfect a formation of the characters, that mechanical
accuracy can alone be compared to it. As this is the simplest in its
construction, it will doubtless supercede all the others. We will now
give its simplest form.
THE LEVER KEY.
This, as we have said, is the most simple form of the key, or
correspondent. It is a modification of that shown at figure 11. The
following figure, 21, represents a key, where the lever is taken
advantage of to make a more perfect connection, with less application
of power. A key of the above form has been used during the past winter
for reporting the proceedings of Congress, and has been found to
operate with ease, with certainty, and with great rapidity. A A is the
block or table to which the parts are secured. E represents the anvil
block. J the anvil, screwed into the block, both of brass. B is another
block, for the stop anvil, K, and the standard for the axis of the
lever C. L is the hammer, and is screwed into the lever, projecting
downward at V, almost in contact with the anvil, J. R is another screw
of the same kind, but in contact with the anvil, K, when the lever C
is not pressed upon. Under the head of each of these two screws, are
tightening screws, which permanently secure the two hammers, to any
adjusted position required for the easy manipulation of the lever, C.
D is a spring which sustains the arm of the key up, preventing the
hammer, L, from making contact with the anvil, J, when not in use. G is
a screw connecting with the brass block, B, and F a screw connecting
with the block, E. To these screws the two wires, I and H, of the
battery are connected. Now, in order to put it in operation, it is
necessary to bring the hammer, V, in contact with the anvil, J, for
so long a time, and at such regular intervals as are required by the
particular letters of the communication. When the key is pressed down,
the fluid passes from the battery to the wire, H, then to the screw, G,
then to the block, B, then to the lever, C, at the axis, S, then to its
metallic anvil, J, then to its screw, F, then to the wire, I, and so to
the battery.
[Illustration: FIG. 21.]
_The circuit of the Electro Magnet, closed and broken
by the movement of the lever itself, acted upon by
the Electro Magnet. Showing the rapidity with which
it is possible to close and break the circuit._
In order to give some idea of the rapidity with which the circuit
may be closed and broken, and answered by the motion of the lever,
a figure, 22, is here introduced to explain its construction and
arrangement. The platform is shown at T, and the upright at S, to
which the coils of the electro magnet, A, are secured by a bolt with
its thumb-nut, E. D a projecting prong of the soft iron, and C the
armature attached to the metallic lever, B, which has its axis or
centre of motion at K, in the same manner as the electro magnet of the
register; R being the standard through which the screws pass. O is the
steel spring secured to R, by a plate, U, upon it, and the screw, N.
L and M are adjusting screws, for the purpose of confining the motion
of the lever, B, within a certain limit. P is a wire with an eye at
the top, through which the end of the steel spring passes, with a hook
at the other end, passing through the lever. The wire, Q, from one of
the coils is connected with the plate, U, at the top of the standard,
R. As the standard, R, is of brass, the plate U, the axis of the lever
of steel, and the lever, B, of brass, all of them being metals, and
conductors of the galvanic fluid, they are made in this arrangement to
serve as conductors. I is the wire proceeding from the other coil, and
is extended to one pole of the battery. The wire, H, coming from the
other pole, is soldered to the metallic spring, J, which is secured to
the upright, S, by means of the adjusting thumb screws, F and G. This
spring is extended to J, where it is in contact with the lever, B. We
have now a complete circuit. Commencing at I, which is connected with
one pole of the battery, from thence it goes to the first coil; then to
the second; then by Q to U, the plate; then to the standard, R; then to
the steel screw, K; then to the steel axis; and then to the lever to
the point, J; where it takes the spring to H, the wire running to the
mercury cup of the other pole of the battery.
[Illustration: FIG. 22.]
The battery being now in action, the fluid flies its circuit; D becomes
a powerful magnet, attracting C to it, which draws the lever down in
the direction of the arrow, X. But since B and J are a part of the
circuit at V, and since, by the downward motion at X, and the upward
motion at V, the circuit is broken at J, the consequence is, that the
current must cease to pass, and D can no longer be a magnet. Hence
the lever at V returns, coming again in contact with J. Instantly the
fluid again passes and the lever at V separates from J. Again the fluid
ceases to pass, and the lever again returns. By this arrangement, then,
the lever breaks and closes the circuit, and it does it in the best
possible manner to show how rapidly the magnet can be made and unmade.
When its parts are well adjusted, its vibrations are so quick that no
part of the lever is distinctly seen. It appears bounded in size by the
limits of its movement up and down, and the motion is so rapid as to
produce a humming noise, sometimes varying the notes to a sharp key. In
this way it will continue to operate so long as the battery is applied.
We infer from this, the almost inconceivable rapidity, with which
it is possible to manipulate at the key of the register in sending
intelligence, far surpassing that of the most expert operator. This
arrangement of the electrome, was devised by Mr. Vail in the summer of
1843.[8]
[8] See Silliman’s Journal, vol. 35, 1839, pages 258-267.
CONDUCTING POWER AND GALVANIC ACTION OF THE EARTH.
After the close of the session of Congress in the spring, 1844, a
series of experiments were commenced by the request of Prof. Morse,
under the direction of Mr. Vail, for the purpose of ascertaining what
amount of battery was absolutely required for the practical operation
of the telegraph. From the first commencement of its operations to the
close of the session, so anxious were the public to witness its almost
magic performances, that time could not be taken to put it in a state
to test either the size of the battery required, or bring into use all
the machinery of the register. On that account, but _one wire_ was used
during that period for transmitting and receiving intelligence, and
the capabilities of the instrument were shown to some disadvantage;
requiring the constant attendance of those having charge of the two
termini.
This first experiment made was to ascertain the number of cups
absolutely required for operating the telegraph. Eighty cups had been
the number in use. Upon experiment, it was found, that two cups would
operate the telegraph from Washington to Baltimore. This success was
more than had been anticipated and urged on further experiments, which
eventually proved that the earth itself furnished sufficient galvanic
power to operate the electro magnet without the aid of a battery.
In the first experiment, a copper plate was buried in the ground,
and about three hundred yards from it, a zinc plate was also buried
in the ground. To each of these plates a wire was soldered, and the
ends brought into the telegraph office, and properly connected with
the key and electro magnet of the register. The battery not being in
connection. Upon manipulating at the key, it was found that the electro
magnet was operated upon and the pen of the register recorded. This led
to another experiment upon a more magnificent scale, and nothing less
than that of using the copper plate at Washington, and the zinc plate
at Baltimore, with the single wire, connecting those distant points,
and the battery thrown out. Here, too, success followed the experiment,
though with diminished effect. By the application of a more delicate
apparatus the _Electro Magnet_[9] was operated upon, and the pen of the
_registering instrument recorded_ its success. From these experiments,
the fact appears conclusive, that the ground can, through the agency of
metallic plates, constantly generate the galvanic fluid.
[9] Franklin appears to have been the first, or among the first, who
used the ground as part of a conducting circuit in the performance
of electrical experiments. Steinheil it appears was the first to use
the ground as a conductor for magneto electricity. Bain, in 1840, was
the first to use the ground as a source of electricity in conjunction
with its conducting power, as a circuit. Prof. Morse, has since the
establishment of the telegraphic line, used the ground as half the
line, with perfect success, employing the battery; and Mr. Vail, in an
experiment in 1844, succeeded in operating the electro magnet, with its
armature attached to a lever, without any battery.
_Six Independent Circuits, with six wires, each wire making an
independent line of communication._
[Illustration: FIG. 23.]
In the above figure, 23, let the right hand side represent Washington,
and the left, Baltimore. The lines marked 1, 2, 3, 4, 5, and 6, between
_m_ and _k_, respectively, represent the six wires connecting (for
example) Washington with Baltimore. Each cluster of black dots, P and
N, represent the batteries of that line upon which it is placed. There
are three batteries at W, and three at B; _m_ 1, _m_ 3, and _m_ 5,
represent the three magnets, or registers, and _k_ 2, _k_ 4, and _k_ 6,
the three keys, or correspondents, at Baltimore; _k_ 1, _k_ 3, and _k_
5, are the three keys, or correspondents, and _m_ 2, _m_ 4, and _m_ 6,
the three magnets, or registers, at Washington. C B is the copper plate
at Baltimore, and C W, the copper plate at Washington, one at each
terminus.
In order to operate the six lines, simultaneously, if required by the
pressure of telegraphic communications, there must be three operators
at each station, commanding their respective keys, and presiding at
their respective registers. If the three operators at Washington choose
to write in Baltimore, together, or in succession, on their respective
registers at the latter place, the galvanic current of the three lines
1, 3, and 5, takes this direction. Commencing at the point, P, of the
three batteries, 1, 3, and 5, at W, it passes to _k_, of the keys;
thence along the wires to _m_, the magnets, 1, 3, and 5 at B; thence
to the single wire, where the three currents join in one to C B, the
copper plate; then through the ground to C W, the other copper plate;
then up the single line to their respective batteries at the point, N,
having each finished its circuit independently of each other.
If, in reply, the three operators at Baltimore wish to write upon
their registers at Washington, either together, or in any succession,
they may choose; the fluid leaves the point, P, of their respective
batteries, at Baltimore, 2, 4, and 6; unite in the single wire to C
B, the copper plate; then pass through the ground in the direction
of arrows to C W, copper plate at Washington, then along the single
wire to their respective magnets, _m_, 2, 4, and 6; then along the
extended wires to _k_, 2, 4, and 6 at Baltimore; and then to N pole of
their respective batteries. In this manner six distinct circuits may
be operated independently of each other, at the same time, or in any
succession, with only one wire for each, and the ground in common, as a
part of the circuit.
It is obvious from the above arrangement that if one wire only,
extended between two distant points, will suffice to enable
communications to be exchanged with each other; that any number of
wires extended, will also, each, individually, give a distinct and
separate line for telegraphic purposes, independently of all the other
lines on the same route.
[Illustration: FIG. 24]
In figure 24, the same arrangement of wires is observed as respects
their number, and the situation of the keys and magnets; but, with this
difference, that instead of six batteries, one for each wire, there is
but one, which is placed upon the single wire, with which the six wires
join. The battery is represented by four black dots, marked N B P. The
course of the fluid in this case is from P to C, the copper plate on
the left side; then through the ground to C, the copper plate on the
right; then through the single wire to any of the six wires, which may
be required, then to the single wire on the left side to N, of the
battery. It is obvious that in this arrangement there is a division of
the power of the battery, depending upon the number of circuits that
may be closed at any one instant. For example: if circuit 1 is alone
being used, then it is worked with the whole force of the battery. If
1 and 2 are used at the same instant; each of them employ one-half the
force of the battery. If 1, 2 and 3 are used, then each use one-third
its power. If 1, 2, 3 and 4, then each circuit has one-fourth the
power; if 1, 2, 3, 4 and 5 are used, at the same moment, then one-fifth
is only appropriated to each circuit, and if 1, 2, 3, 4, 5 and 6, then
each employ a sixth part of the galvanic fluid generated by the battery.
MODE OF SECRET CORRESPONDENCE.
The great advantage which this telegraph possesses in transmitting
messages with the rapidity of lightning, annihilating time and space,
would perhaps be much lessened in its usefulness, could it not avail
itself of the application of a secret alphabet. We will now proceed
to describe some of the various systems by which a message may pass
between two correspondents, through the medium of the telegraph, and
yet the contents of that message remain a profound secret to all
others, not excepting the operators of the telegraphic stations,
through whose hands it must pass.
For this purpose let the telegraphic characters representing particular
letters be transposed and interchanged. Then the representative of _a_,
in the _permanent_ alphabet, may be represented by _y_, or _c_, or
_x_, in the _secret_ alphabet; and so of every other letter. As there
are twenty-seven characters in the telegraphic alphabet, they can, by
transposition, furnish six hundred and seventy-six different kinds of
secret alphabets; nearly two for every day of the year. Two persons
have agreed to use, in their telegraphic correspondence, the secret
alphabet. From the six hundred and seventy-six combinations, they have
selected one for each day in the year, and given each their particular
date. In the course of their business, it becomes necessary on the
first of July, for one to transmit important information to the other.
He then refers to the telegraphic book, for the alphabet belonging to
that date, and from it writes his communication, as follows: _The firm
of G. Barlow & Co. have failed._ He runs his eye along the alphabetical
column for _t_, and finds that for the first of July it is _e_, that
_h_ is _j_, _e_ is _n_, and in the same manner, he proceeds with the
remaining letters of his message, which, when completed, reads as
follows: _Ejn stwz ys & qhwkyf p iy jhan shtknr_. As every person
employing the telegraph has his name, occupation and place of business
registered in the record book of the office, with his telegraphic
number, we will suppose, that _Mr. Hammond, Builder, 57 Anson-st.
Philadelphia_, sends the above communication to the office for _Messrs.
Talford & Co. Lumber Merchants, 41 Bradford-st. New York_. In the
record, the former name is numbered 14; and the latter 31. The private
message is then directed thus, _No. 14 to No. 31_, and reads thus:
Mr. Hammond, &c. sends the following communication to Messrs. Talford
& Co. &c. “The firm of G. Barlow & Co. have failed.” This message,
in substituted characters, is copied at the receiving station, and
immediately delivered. The messenger returns with the following: _Syw
fjhe hzyxce._ To which is prefixed _No. 31 to No. 14_. This is sent to
Mr. Hammond, who, on translating it, discovers that it must be answered
by figures. He then refers to the secret numerals, under the date of
the first of July, and finds the private numerals required are 897,
312, adding to it a few letters, when it reads thus, _No. 14 to No.
31, 879, 312 rykkm_. If it should happen, that on the 6th of December,
or 13th of May, it was necessary to send a private communication, the
secret alphabets of those dates are used, and so for any date of the
year.
July 1st. | March 28th. | December 6th. | May 13th.
| | |
A change to H | A change to A | A change to Q | A change to X
B change to Q | B change to N | B change to P | B change to M
C change to I | C change to O | C change to N | C change to G
D change to R | D change to V | D change to O | D change to T
E change to N | E change to P | E change to V | E change to L
F change to S | F change to C | F change to A | F change to F
G change to & | G change to Q | G change to C | G change to &
H change to J | H change to D | H change to R | H change to K
I change to T | I change to R | I change to D | I change to S
J change to B | J change to E | J change to & | J change to N
K change to U | K change to S | K change to E | K change to Z
L change to K | L change to F | L change to Z | L change to J
M change to Z | M change to T | M change to F | M change to P
N change to C | N change to G | N change to X | N change to E
O change to Y | O change to U | O change to G | O change to U
P change to L | P change to H | P change to W | P change to I
Q change to D | Q change to B | Q change to H | Q change to V
R change to W | R change to I | R change to B | R change to B
S change to M | S change to & | S change to I | S change to Y
T change to E | T change to J | T change to U | T change to O
U change to X | U change to Z | U change to J | U change to H
V change to A | V change to K | V change to Y | V change to Q
W change to F | W change to Y | W change to K | W change to D
X change to O | X change to L | X change to S | X change to W
Y change to V | Y change to X | Y change to L | Y change to A
Z change to G | Z change to M | Z change to T | Z change to R
& change to P | & change to W | & change to M | & change to C
1 change to 5 | 1 change to 6 | 1 change to 0 | 1 change to 7
2 change to 7 | 2 change to 1 | 2 change to 9 | 2 change to 8
3 change to 1 | 3 change to 7 | 3 change to 4 | 3 change to 6
4 change to 8 | 4 change to 2 | 4 change to 5 | 4 change to 9
5 change to 2 | 5 change to 8 | 5 change to 3 | 5 change to 4
6 change to 9 | 6 change to 3 | 6 change to 8 | 6 change to 1
7 change to 3 | 7 change to 9 | 7 change to 6 | 7 change to 0
8 change to 0 | 8 change to 4 | 8 change to 2 | 8 change to 5
9 change to 4 | 9 change to 0 | 9 change to 7 | 9 change to 2
0 change to 6 | 0 change to 5 | 0 change to 1 | 0 change to 3
The transposed secret alphabet is not perfectly secure for private
messages, when the message contains more than eight or ten words. It
is, therefore, necessary to adopt some of the following modes of making
it perfectly incomprehensible, and beyond the power of any person to
decypher it. Any one or two, or more, of these modes may be selected
and combined for this purpose. Let the following key or transposed
alphabet, be used in illustrating the following rules:
A to R | F to X | K to U | P to E | U to K | Z to M
B Y | G B | L V | Q P | V G | & I
C Z | H T | M D | R L | W N |
D A | I W | N & | S F | X J |
E S | J C | O Q | T O | Y H |
1st. Let the last letter of a word remain unchanged, viz.
_Rome_, transposed, _lqde_.
2d. Let the first letter of a word remain unchanged, viz.
_Rome_, transposed, _rqds_.
3d. Let the first and last letter remain unchanged, viz.
_Rome_, transposed, _rqde_.
4th. Let the middle letter of a word of 5, 7, 9 or 11 letters
remain unchanged, viz. _First_, transposed, _xwrfo_, and
in words of 4, 6, 8, 10 or 12 letters, let the two middle
letters remain unchanged, viz. _Rome_, transposed, _loms_.
5th. Let the first, middle, and last letters of a word remain
unchanged, viz. _first_, transposed, _fwrft_.
6th. Let the middle letter of words of 5, 7, 9, 11 or 13
letters commence the word, viz. _first_, transposed,
_lxwfo_.
7th. Let the two middle letters of a word of 4, 6, 8, 10 or 12
letters commence the word, viz. _Rome_ transposed, _qdls_.
8th. In a word of 4, 6, 8, 10, 12 or 14 letters, let the first
half of the word be substituted for the last half, viz.
_Rome_, transposed, _dslq_.
9th. Let every other entire word be reversed, viz. _What is
the news_, transposed, _ntro fw ots fns_ &.
10th. Let every third word be reversed.
11th. Let every fourth word be reversed.
12th. Let every fifth word be reversed.
13th. Let the three middle letters of every word of 5, 7, 9,
11 or 13 letters be reversed, viz. _first_, transposed,
_xflwo_.
14th. Let every word of two or three letters be prefixed to
the beginning of the following word, or affixed to the end
of the preceding word, viz, _State of Maine_, transposed,
_forosqx drw&s_.
15th. Let one, where double letters occur in a word, be
excluded, viz. _will_ transposed, _nwv_.
16th. Where two or more words, of two or three letters, follow
each other, let them be joined together, viz. _Cotton is
on the rise_, transposed, _zqoq& wfq&ots lwfs_.
17th. Make no separation between words of less than eight
letters, viz. _Cotton is on the rise_, transposed,
_zqoq&wfq&otslwfs_.
18th. Make no separation between words.
19th. Reverse the order of the letters of the whole message,
viz. _Cotton is on the rise_, transposed and reversed,
_sfwl sto &q fw &qoqz_.
20th. Change the key, alternately, every ten or fifteen words,
using two keys.
21st. Let the two first letters of all words of four letters
be affixed to the end of the preceding word, and the
remaining two letters be prefixed to the word following,
viz. _stocks have fallen_, transposed, _foqzuftr gsxrvs&_.
22d. Change the key irregularly, thus, for example, the first
three words transpose from one key; the next three words from
another key; the next three from another key, and so on.
23d. Reverse the termination of those words ending with _tion_,
_sion_, _ness_, _less_, _tive_, _ty_, _ly_, _ed_, &c.
24th. Make a division of long words into two.
25th. Let those words which occur frequently and have only two
or three letters remain unchanged, viz. _to_, _a_, _the_,
_of_, _and_, _for_, _with_, &c.
26th. Let every two words, or every three, or every four, be
reversed.
27th. Omit one vowel in every word.
28th. Omit the letter _e_ at the beginning and end of a word.
29th. Omit the letter _i_ or _y_ at the beginning and end of a
word.
30th. Omit the letter _o_ at the beginning and end of a word.
31st. In words of 4, 6, 8, 10 or 12 letters, let the first of
the two middle letters commence the word, and the last of
the two middle letters end the word.
32d. Let _t_ signify _the_; _e_ for _of the_; _f_ for _of_;
_u_ for _you_; _wi_ for _with_; _i_ for _by_; _tt_ for
_that_; _ts_ for _this_; _fr_ for _from_; _n_ for _no_
or _not_; _w_ for _will_; _td_ for _to-day_; _tm_ for
_to-morrow_; _s_ for _was_; _sh_ for _shall_; _wd_ for
_would_; _sd_ for _should_; _cd_ for _could_; _te_ for _to
the_.
We have here given a few of the various modes, by which a message can
be made so complicated, that no clue will be given that shall enable
the inquisitive to decypher it. Others may be easily devised, and as it
is better that those using the secret alphabet should devise their own
modes of transposition and reversion, none others need be given.
The following is written from the secret alphabet, and afterwards
rendered more obscure by one of the methods laid down above. The key
does not accompany it. Who can decypher it?
zbpvp yslup nbguxpyu zbyi, lovmy-&-yux gxp, zlegvt
lovappai lubyizlvji hozovpsg zplup cbynb zbvloxbgm _the_
jpgvizl nlep ibgm izgua zlnvlvlcu _the_ inypvnp lhlov
xmlvyloi mgua, _the_ pnpuzvyn wmgrhzb gzhmgibpili’pv
_the_ itjcbpu _the_ gypagvlpui _and the_ izlveyi byxbwj
wlma yu & puzyla _and_ iovsguyux ilymulc wlci, giowkpnzl
_the_ bvegu cymicyhzpv zbgu zbloxbz zb’ yuzpurp _and_
iowzmp. Zlal egu’i wyayux hmypi gmlux _the_ cyop. Lmazyep
yinlufopvpa, ayizgunpyi l’ pvbvlcu, _and_ ul&g rpewmy
klyui _the_ zlvyarlup. Hgep ibgmwp byicblip ipgvnbyux eyua
byixy&pu. Zlegu _the_ slcpvzl oip _the_ hyvp _of_ bpg&pu,
_and the_ lmahgwmpi, cbynbyu mpxpuai voulh bgvpiyux
_the_ blvipi _of the_ iou, sppeulc ulhgwmpi, iyunp, elvp
cluavloihgv, bpjltpi _the_ myxbzuyux zlbyi vgsya ngv;
pgepibgmwp byi; _and_ cbpuyu hozovp agji sbymlilsbj
bpveluvepuz ibymgyzp zlzbip cblwlmapiz mgci, luth eigep
zgwmpz cyzblov hvgulmyu’i ugep zbyup, elvip, yuwmgryux
nbgvgnzpvi ibgmhmgep.
The following is from another key.
grvlvhmz agcxv hrvy _all the_ zacyavzwe rexzgvlcekz,
gvmarcyohc gradevn neelz; rmqcyogrvcl cycgcmgvn, grvclredt
dmyokmova ndgrvcl blvxmzeylt, srlcaz, ovexvglt, xvncacyv,
olmxml, rczgelt, _all were_ gmkorgi ndmgcy, _they_ zmcdvn
_in the_ adcknz, bmlmueqv _the_ qkdoml; _and they_ dvgbmd
mgth ekgxezg. Lex grvcl zkudexv umbwa bohnvgmarvn dvmqvz
hrcar xvy _were to_ gmwvks hcgrolvmg lvzsvag, ukghrcar
_they were not_ sulxcgvnt opknov, yehvqvlt greyoi
sarmyovn, ovycqz odelcozi nxmwcyo cyzvdb kynvlzgen _by
the_ xmyt; _and_ mbgvl rmqcyo zemlvn _to the_ vgrvlvmd
lvocyzo fzacvyav _in_ elnvl grvlv _to_ zuciv _the_ glqt
gr _in_ rvlrcorvzg lvglvmgz, _it_ vxsdetz, cgsehvl _in_
mzalgmcycyo _the_ hmtumaw, _to_ vrnlgr _and in_ mslemarcyo
odezvdt _to us_ grmgi txmt zreh _us the_ lekgv _it has_
glmqvdvn, _and the_ zvalvgz _it has_ glmqvdvn, _and the_
zvalvgz _it has_ ncx aeqvlvn, ukg, cbzkar isye hthemdxezg
kycqvlzmd gvynvyat _of the_ rkxmy zaev yavz _it was_
vgvl _the_ nczgcyagcqv armlmayvlczgca _of_ glkv zacvyavz
amynczsvyzv _with the_ svesdv _as the_ svesdv _as the_
svesdv nczsvyzv _with them_; glkvgrvedeotey the aeyglmlt,
rmzyvn _of the_ svezdvmz _the_ svesdv rmqvv frvl zrvokmlnz
grvcl lvdcocey; _and_ grvcl lvdocey, _in_ cgzgklx, okmlnz
rvl _he to_ grvx hrvy grvedeot dmyokczrvz, _and_ nevzyeg
zsvmwtogrvx; _he to_ rvlhrvg _the_ lvdcocey _of the_
arklarvz yvodvag rvl _and_ avmzvz _to_ vzgvoxrvl; hvxkzg
grvyzv _to it_. uegrey rvlmaekyg _and_ eygrvclz, grmgzrv
zsvmwz _to them_ rvmlz _them_ zgkncvz _in_ lvbvlvyav _to
them and_ wvsz grvcl zarcedz esvymz eklgvxsdvz mlv.
Another example of the manner of writing secret correspondence is here
given, and for those to decypher who can.
ibeg pycydc peocyenxez yndexc tcacbp bepkpaetzo
pcpcgkocevd pqzpeuw bpwuaqy iatdd pctpcawu uyyc elgcvkwl
tytp wlwlxgy ppe kepcuwnc ptkeb badokecy in vkqunwac
wuatza qodazw prvsaue tpeoebztqg ckphvkwv epgyecp wzqv
adyge zcgtey eppd wubk prozlwy pwzopwzieydt. tytp wzqv
tytp qznokw ptpcawu yclep tcbbcg epdptp tytzenncyp ywzpw
lccypetglydcn ezwgo eppd igwdc czgt tbzwp lhzuczpowxck,
acktepzgh tvkextpc aeptveg jezpcktncw epcgh gwvcncxc
cgbtpy iatdd pvgcvcw itgzcxch qkcczn zwkkepcpwgc
pzuczpowxck tzckptutzo pwcytmp, eppd ypepcb zoypdt _in_
lceppd pypvw watbc, in tpykpeptwzpkezyvw beyawkcyzwvnczac
jiyzc, in geozwp dkqwy lqphyne txnled ppkeztuyytwz cucye
zoypdt wodpdk ezdpwck tquucn; jeppd etquucn lcqozwtzo
pwvkextpe tzntntxqegy jawzwkpgcn pvkextpc xictyj kypytzpc.
Another plan for sending secret intelligence, is, that of using select
sentences, previously agreed upon by correspondents. In this plan,
the first letter of each word in the sentence, combined, is made the
representative of that sentence, as in the following examples:
iwrom I will return on Monday.
mhii My health is improving.
shf Stocks have fallen.
smtbop Send me ten barrels of pork.
ymir Your message is received.
dygml Did you get my letter?
gmlt Give my love to.
witsotmf What is the state of the market for?
cha Cotton has advanced.
cwycit Call when you come in town.
sosn Sails on Saturday next.
hjaip Has just arrived in port.
hyfmo Have you filled my order?
wmietg When may I expect the goods?
wyegfef Will you exchange gold for eastern funds?
Another arrangement, equally adapted to the same purpose as the last,
is that of taking the first letter of the sentences, then arranging
them in alphabetical order, and numbering them, thus:
a. 1. At five o’clock I leave for home.
a. 2. A thunder storm is rising in the west.
c. 1. Can you send me?
c. 2. Cotton has advanced a little to-day.
h. 1. How much have stocks fallen?
h. 2. Have you received my last package?
h. 3. Has the rain done much damage?
t. 1. The weather is excessively hot.
t. 2. There is no demand for tobacco.
t. 3. Take all they have at that price.
t. 4. The Eliza sails to-morrow with full cargo.
t. 5. The steamer Caledonia has just arrived.
w. 1. What news does she bring?
w. 2. What is the state of the market for sugar?
These two systems have been found to answer in practice, and were much
used in telegraphic business during the last session of Congress.
[From Silliman’s Journal.]
ART. XVI. _Experiments made with one hundred
pairs of Grove’s battery, passing through one
hundred and sixty miles of insulated wire_; in a
letter from Prof. S. F. B. Morse, to the Editors,
dated New York, Sept. 4th, 1843.
Dear Sirs—On the 8th of August, having completed my
preparations of 160 miles of copper wire for the Electro
Magnetic Telegraph, which I am constructing for the
government, I invited several scientific friends to witness
some experiments in verification of the law of Lenz, of
the action of galvanic electricity through wires of great
lengths. I put in action a cup battery of one hundred
pairs, which I had constructed, based on the excellent plan
of Prof. Grove, but with some modifications of my own,
economising the platinum. The wire was reeled upon eighty
reels, containing two miles upon each reel, so that any
length, from two to one hundred and sixty miles, could be
made at pleasure to constitute the circuit. My first trial
of the battery was through the entire length of 160 miles,
making of course a circuit of 80 miles, and the magnetism
induced in my electro magnet,[10] which formed a part of the
circuit, was sufficient to move with great strength, my
telegraphic lever. Even forty-eight cups produced action in
the lever, but not so promptly or surely.
We then commenced a series of experiments upon
decomposition, at various distances. The battery alone (100
pairs) gave, in the measuring gauge in one minute, 5.20
inches of gas. When four miles of wire were interposed, the
result was 1.20 inches; ten miles of wire, .57; 20 miles,
.30 inches; 50 miles, .094. The results obtained from a
battery of 100 pairs are projected in the following curve:
[10] In Prof. Daniel’s, Introduction to the Study of Chemical
Philosophy, 2d edition, 1843, there are these facts to be noticed. In
the preface, there are these words: “It only remains for me now, to
acknowledge my obligations to my friends and colleagues, _Professor
Wheatstone_ and Dr. Todd, for their great kindness in undergoing the
disagreeable labour of revising and correcting the proof sheets. They
have thereby prevented many errors which would have otherwise deformed
the work.”
No statement then of Prof. Daniel’s, particularly in that part of his
work which related especially to Wheatstone’s Telegraph, would be
allowed to pass unnoticed by Mr. Wheatstone and we are authorized in
considering any such statement as having his sanction.
We then find, page 576, the following statement: “Ingenious as Prof.
Wheatstone’s, contrivances are, they would have been of no avail for
telegraphic purposes, without the investigation which he was the first
to make of the laws of electro magnets, when acted on through great
lengths of wire. _Electro magnets of the greatest power, even when the
most energetic batteries are employed, utterly cease to act when they
are connected by considerable lengths of wire with the battery._”
If any thing were needed to show that Prof. Wheatstone was not the
inventor of the _Electro Magnetic Telegraph_, it is this assertion
(under the supervision of Prof. Wheatstone) made by Prof. Daniel. In
1843, Prof. Wheatstone had not made the discovery upon which Prof.
Morse bases his invention, viz. that _Electro Magnets can be made to
act, with an inconsiderable battery too, when the latter is connected
with the former by considerable lengths of wire_: 80 miles may
certainly be considered as of _considerable length_.
[Illustration: FIG. 25.]
_Table constructed from the Curve._
Battery alone 5.20 inches.
1 mile 3.85 “
2 “ 2.62 “
3 “ 1.84 “
4 “ 1.20 “
5 “ 1.05 “
6 “ .92 “
7 “ .80 “
8 “ .71 “
9 “ .64 “
10 “ .57 “
20 “ .30 “
30 “ .20 “
40 “ .14 “
50 “ .094 “
During the previous summer, I made the following
experiments, upon a line of 33 miles, of number 17 copper
wire, with a battery of 50 pairs. In this case, I used a
small steelyard, with weights, with which I was enabled to
weigh, with a good degree of accuracy, the greater magnetic
forces, but not the lesser, yet sufficiently approximating
the recent results to confirm the law in question.
_Table of Results._
50 pairs through 2 miles attracted and raised 9 ozs.
“ 4 “ “ “ 4 “
“ 6 “ “ “ 3 “
“ 8 “ “ “ 2½ “
“ 10 “ “ “ 2¼ “
“ 12 “ “ “ ⅛ “
“ 14 “ “ “ ⅛ “
and each successive addition of two miles, up to 33,
still gave an attractive and lifting power of one-eighth
of an ounce.
_Curve from these Results._
[Illustration: FIG. 26.
A great irregularity is seen between the 10th
and 12th miles, which is due, undoubtedly, to a
deficiency of accuracy in the weighing apparatus.
I take pleasure in sending you the following
calculation of the law of the conducting power of
wires, for which I am indebted to my friend Prof.
Draper, of the New York City University.
_On the Law of the Conducting Power of Wires. By John W. Draper, M. D.
&c. &c._]
It has been objected, that if the conducting power of
wires, for electricity was inversely as their length, and
directly as their section, the transmission of telegraphic
signals, through long wires, could not be carried into
effect, and even the galvanic multiplier, which consists,
essentially, of a wire making several convolutions round a
needle, could have no existence. This last objection was
first brought forward by Prof. Ritchie, of the University
of London, as an absolute proof, that the law referred to
is incorrect. There is, however, an exceedingly simple
method of proving that signals may be despatched through
very long wires, and that the galvanic multiplier, so far
from controverting the law in question, depends for its very
existence upon it.
Assuming the truth of the law of Lenz, the _quantities_ of
electricity which can be urged by a constant electromotoric
source through a series of wires, the lengths of which
constitute an arithmetical ratio, will always be in a
geometrical ratio. Now the curve whose ordinates and
abscissas bear this relation to each other, is the
logarithmic curve whose equation is _aʸ_ = _x_.
1st. If we suppose the base of the system, which the curve
under discussion represents, be greater than unity, the
values of _y_ taken between _x = 0_, and _x = 1_, must be
all negative.
2d. By taking _y = 0_, we find that the curve will
intersect the axis of the _x_’s, at a distance from the
origin, equal to unity.
3d. By making _x = 0_, we find _y_ to be infinite and
negative. Now, these are the properties of the logarithmic
curve, which furnish an explanation of the case in hand.
Assuming that the _x_’s represent the quantities of
electricity, and the _y_’s the lengths of the wires, we
perceive at once, that those parts of the curve which we
have to consider, lie wholly in the fourth quadrant, where
the abscissas are positive and the ordinates negative.
When, therefore, the battery current passes without the
intervention of any obstructing wire, its value is equal to
unity. But, as successive lengths of wire are continually
added, the quantities of electricity passing, undergo a
diminution, at first rapid, and then more and more slow.
And it is not until the wire becomes infinitely long that
it ceases to conduct at all; for the ordinate _y_, when _x
= 0_, is an asymptote to the curve. In point of practice,
therefore, when a certain limit is reached, the diminution
of the intensity of the forces becomes _very small_,
whilst the increase in the lengths of the wire is vastly
great. It is, therefore, possible to conceive a wire to
be a million times as long as another, and yet, the two
shall transmit quantities of electricity not perceptibly
different, when measured by a delicate galvanometer. But,
under these circumstances, if the long wire be coiled, so
as to act as a multiplier, its influence on the needle
will be inexpressibly greater than the one so much shorter
than it. Further, from this we gather that for telegraphic
despatches, with a battery of given electromotoric power,
when a certain distance is reached, the diminution of effect
for an increased distance becomes inappreciable.
THE GALVANOMETER OR GALVANOSCOPE.
This useful instrument, the invention of which is based upon Oersted’s
discovery of the deflection of the magnetic needle, by the action
of conducting wires conveying galvanic currents, seems to have
furnished to most of the inventors of telegraphs, the main spring of
communication. It was a very natural suggestion, as being the most
convenient and ready mode of obtaining the required motion, by making
and breaking the galvanic circuit. Thus Steinheil, Wheatstone and
Bain have availed themselves of this _one idea_ to effect that part
of the telegraphic operation which may be called the _galvanic_, in
contradistinction to the _mechanical_ parts, which last have varied
considerably with different operators. The construction and operation
of the galvanometer may be understood by reference to the figures 27,
28, 29. A A, fig. 28, are two long coils of covered copper wire, a side
view of which is shown in fig. 27. These coils are connected with the
binding screws, L L, attached to the frame, or box, holding the coils.
Two coils are used for the convenience of allowing the pivot sustaining
the magnetic needle to pass between them; one coil might be used, by
leaving room enough between the wires for a socket for the pivot,
but the arrangement, represented, is the most readily constructed. A
side view of the instrument, figure 27, shows the arrangement of the
needles, two of them being generally used to increase the operation of
deflection, and to neutralize the influence of the earth’s magnetism.
The pair of needles is usually denominated, an _astatic_ needle, or a
needle without directive power; as the current traversing a conducting
wire gives different directions to needles placed above and below the
wire, the action upon the two needles thus placed is combined, by
arranging their poles in opposite directions. When the current is in
the direction indicated by the arrows in figure 27, the north pole
of the needle, within the coil, is carried in a direction from you,
as you face the drawing, and the north pole, without the coil, in a
contrary direction. The operation upon the south pole is the reverse.
Changing the direction of the galvanic current, reverses the motions.
It is usual to apply the force of torsion, or of a _hair_ spring, or
of the superior weight of one extremity of the needle, to act against
the deflective force of the current, and to attach a graduated scale to
the instrument, fixing it between the uppermost needle and the coils as
in figure 29. Instead of deflecting the needle, the coils themselves
may be deflected, as in the galvanoscope of Prof. Page, invented in
January, 1837, and described by him in the 33d vol. of Silliman’s
Journal, page 376. The object of this contrivance was to enable him
to use powerful magnets and lighter coils. This modification of the
galvanoscope, Mr. Bain has preferred as the means of operating his
telegraph.
[Illustration: FIG. 27.]
[Illustration: FIG. 28.]
[Illustration: FIG. 29.]
_An Interesting Experiment of Supporting a Large Bar of Iron within the
Helix. Discovered by Mr. Vail, January, 1844._
It has been shown, many years since, that a magnetic needle would be
drawn into and suspended within a helix, conveying a galvanic current,
and that in the case of using large bar magnets, the coils or helices
might be made to move over them, as in De La Rives’s rings; but in no
instance, I believe, has it been recorded, or observed, that a bar of
iron weighing a pound or more, could be drawn up into the helix and
there sustained in the air, as it were, without support. If the helix,
as shown in figure 30, be connected with from 6 to 12 pairs of Grove’s
battery, the bar may be drawn up into its centre and there sustained in
a vertical position by the action of the helix, forming an exceedingly
interesting and paradoxical experiment.
[Illustration: FIG 30.]
[From the National Intelligencer.]
APPLICATION OF THE ELECTRO MAGNETIC TELEGRAPH TO THE DETERMINATION OF
LONGITUDE.
Among the wonderful developements of the new telegraph, one has just
came to light which will be regarded in the world of science as deeply
interesting. Prof. Morse suggested to the distinguished Arago, in 1839,
that the electro magnetic telegraph would be the means of determining
the difference of longitude between places with an accuracy hitherto
unattainable. By the following letter from Capt. Charles Wilkes to
Prof. Morse, it will be believed that the first experiment of the kind
of which we have any knowledge, has resulted in the fulfilment of the
Professor’s prediction.
WASHINGTON, _June 13, 1844_.
MY DEAR SIR—The interesting experiments for
obtaining the difference of longitude through your magnetic
telegraph were finished yesterday and have proved very
satisfactory. They resulted in placing the Battle Monument
square, Baltimore, 1 _m_, .34 sec. .868 east, of the
capitol. The time of the two places was carefully obtained
by transit observations. The comparisons were made through
chronometers and without any difficulty. They were had in
three days, and their accuracy proved in the intervals
marked and recorded at both places. I have adopted the
results of the last day’s observations and comparisons,
from the elapsed time having been less.
The difference of the former results, found in the
American Almanac, is .732 of a second. After these
experiments, I am well satisfied that your telegraph offers
the means for determining meridian distances more accurately
than was before within the power of instruments and observers.
Accept my thanks, and those of Lieutenant Eld, for
yourself and Mr. Vail, for your kindness and attention in
affording us the facilities to obtain these results. With
great respect and esteem, your friend,
CHARLES WILKES.
Professor S. F. B. MORSE,
_Capitol, Washington_.
MODE OF CROSSING BROAD RIVERS, OR OTHER BODIES OF WATER, WITHOUT WIRES.
The following extract from Professor Morse’s letter to the Secretary
of the Treasury, and by him submitted to the House of Representatives,
Dec. 23, 1844, in relation to this interesting subject, will
sufficiently illustrate it:
“In the autumn of 1842, at the request of the American Institute, I
undertook to give to the public in New York a demonstration of the
practicability of my telegraph, by connecting Governor’s Island with
Castle Garden, a distance of a mile; and for this purpose I laid my
wires properly insulated beneath the water. I had scarcely begun
to operate, and had received but two or three characters, when my
intentions were frustrated by the accidental destruction of a part
of my conductors by a vessel, which drew them up on her anchor, and
cut them off. In the moments of mortification, I immediately devised,
a plan for avoiding such an accident in future, by so arranging my
wires along the banks of the river as to cause the water itself to
conduct the electricity across. The experiment, however, was deferred
till I arrived in Washington; and on December 16, 1842, I tested my
arrangement across the canal, and with success. The simple fact was
then ascertained, that electricity could be made to cross a river
without other conductors than the water itself; but it was not until
the last autumn that I had the leisure to make a series of experiments
to ascertain the law of its passage. The following diagram will serve
to explain the experiment.
[Illustration: FIG. 31.]
A, B, C, D, are the banks of the river; N, P, are the battery; E is
the electro magnet; _w w_, are the wires along the banks, connecting
with copper plates, _f_, _g_, _h_, _i_, which are placed in the water.
When this arrangement is complete, the electricity, generated by the
battery, passes from the positive pole, P, to the plate _h_, across
the river through the water to plate _i_, and thence around the coil
of the magnet, E, to plate _f_, across the river again to plate _g_,
and thence to the other pole of the battery, N. The numbers 1, 2, 3, 4,
indicate the distance along the bank measured by the number of times of
the distance across the river.
The distance across the canal is 80 feet; on August 24th, the following
were the results of the experiment.
---------------------+-------+--------+------+-------+-------+--------
No. of the | 1st. | 2d. | 3d. | 4th. | 5th. | 6th.
experiment, | | | | | |
---------------------+-------+--------+------+-------+-------+--------
No. of cups in | | | | | |
battery, | 14 | 14 | 14 | 7 | 7 | 7
Length of conductors,| | | | | |
_w_, _w_, | 400 | 400 | 400 | 400 | 300 | 200
Degrees of motion of | | | | | |
galvanometer, |32 & 24|13½ & 4½| 1 & 1|24 & 13|29 & 21|21½ & 15
Size of the copper | | | | | |
plates | | | | | |
_f_, _g_, _h_, _i_, |5 by 2½|16 by 18|6 by 5|5 by 2½|5 by 2½| 5 by 2½
| ft.| in.| in.| ft.| ft.| ft.
---------------------+-------+--------+------+-------+-------+--------
Showing that electricity crosses the river, and _in quantity in
proportion to the size of the plates in the water._ The _distance
of the plates on the same side_ of the river _from each other_ also
affects the result. Having ascertained the general fact, I was desirous
of discovering the best practical distance at which to place my copper
plates, and not having the leisure myself, I requested my friend
Professor Gale to make the experiments for me. I subjoin his letter and
the results.
NEW YORK, _November_ 5th, 1844.
MY DEAR SIR—I send you, herewith, a copy of
a series of results, obtained with four different sized
plates, as conductors to be used in crossing rivers. The
batteries used were six cups of your smallest size, and
one liquid used for the same throughout. I made several
other series of experiments, but these I most rely on for
uniformity and accuracy. You will see, from inspecting the
table, that the distance along the shores should be _three
times greater_ than that from shore to shore across the
stream; at least, that four times the distance does not
give any increase of power. I intend to repeat all these
experiments under more favorable circumstances, and will
communicate to you the results.
Very respectfully,
L. D. GALE.
Professor S. F. B. MORSE,
_Superintendent of Telegraphs_.
Series of Experiments on four different sizes of plates,
to wit: 1st, 56 square inches; 2d, 28 square inches; 3d,
14 square inches; and 4th, 7 square inches.
_Experiment 1st.—Surface of one face of the copper plate,
56 square inches; battery, Morse’s
smallest, 6 cups._
NOTE.—In all the experiments,
_f_ and _g_ are stationary.
--------+--------+---------+---------+------+------+------+------
Distance| | | | | | |
from |Distance| | | | | |
bank | along | 1st | 2d | 3d | 4th | 5th | 6th
to bank.| shore | Trial. | Trial. |Trial.|Trial.|Trial.|Trial.
--------+--------+---------+---------+------+------+------+------
1 | 1 | 22° | 23° | 23° | 22° | 22° | 22°
--------+--------+---------+---------+------+------+------+-------
1 | 2 | 31 | 32 | 31½ | 31 | 31 | 31
--------+--------+---------+---------+------+------+------+-------
1 | 3 | 36 | 36 | 35½ | 35 | 35 | 35
--------+--------+---------+---------+------+------+------+-------
1 | 4 | 36 scant| 36 scant| 34½ | 34 | 34 | 34
--------+--------+---------+---------+------+------+------+-------
_Experiment 2d.--Plates 28 square inches,
conducted as above._
--------+--------+-------+-------+-------+-------+----------+-------
Distance| | | | | | |
from |Distance| | | | | |
bank | along | 1st | 2d | 3d | 4th | 5th | 6th
to bank.| shore | Trial.| Trial.| Trial.| Trial.| Trial. | Trial.
--------+--------+-------+-------+-------+-------+----------+-------
1 | 1 | 18° | 17° | 17° | 17° | 17° | 17°
--------+--------+-------+-------+-------+-------+----------+-------
1 | 2 | 27 | 26 | 27½ | 27½ | 27½ | 27
--------+--------+-------+-------+-------+-------+----------+-------
1 | 3 | 31 | 31 | 31 | 31 | 31 | 31
--------+--------+-------+-------+-------+-------+----------+-------
1 | 4 | 31 | 31 | 31 | 31 | 31 scant.| 31
--------+--------+-------+-------+-------+-------+----------+-------
_Experiment 3d.--Plates 14 square inches,
conducted as No. 1._
-------------+-----------+------+------+------+------+------+------
Distance from| Distance | 1st | 2d | 3d | 4th | 5th | 6th
bank to bank.|along shore|Trial.|Trial.|Trial.|Trial.|Trial.|Trial.
-------------+-----------+------+------+------+------+------+------
1 | 1 | 8° | 8½° | 8½ | 8° | 8° | 8°
1 | 2 | 19½ | 20 | 19½ | 19 | 19 | 19
1 | 3 | 23½ | 23½ | 23½ | 23½ | 23½ | 23½
1 | 4 | 24½ | 24½ | 23½ | 23½ | 23½ | 23½
-------------+-----------+------+------+------+------+------+------
_Experiment 4th.--Plates 7 square inches,
conducted as No. 1._
-------------+-----------+------+------+------+------+------+------
Distance from| Distance | 1st | 2d | 3d | 4th | 5th | 6th
bank to bank.|along shore|Trial.|Trial.|Trial.|Trial.|Trial.|Trial.
-------------+-----------+------+------+------+------+------+------
1 | 1 | 5° | 5° | 5° | 5° | 3° | 3°
1 | 2 | 15 | 14½ | 14 | 15 | 15 | 12
1 | 3 | 17½ | 18 | 17½ | 17½ | 18 | 17
1 | 4 | 18 | 18 | 18 | 17½ | 17½ | 17
-------------+-----------+------+------+------+------+------+------
The distance from bank to bank, 30 inches. Depth of water,
12 inches. In experiment 4, the liquor of the batteries was
very weak, exhausted towards the last; and in trials 5 and
6, the irregularities are to be attributed in part to the
weak liquor, and in part to the twilight hour at which the
experiments were made.
As the result of these experiments, it would seem that there may
be situations in which the arrangements I have made for passing
electricity across the rivers may be useful, although experience alone
can determine whether lofty spars, on which the wires may be suspended,
erected in the rivers, may not be deemed the most practical. The
experiments made were but for a short distance; in which, however, the
principle was fully proved to be correct. It has been applied under the
direction of my able assistants, Messrs. Vail and Rogers, across the
Susquehanna river, at Havre-de-Grace, with complete success; a distance
of nearly a mile.
TELEGRAPHIC CHESS PLAYING
In order to give some idea of the accuracy with which the telegraph
transmits intelligence, we here give two games of chess, as played by
distinguished gentlemen in Baltimore and in Washington. The two games
are selected from the seven played. The number of moves made in playing
the seven games, were 686, and were transmitted without a single
mistake or interruption. The Baltimoreans played with the white pieces,
placed on numbers 57, 58, 59, 60, 61, 62, 63, and 64, figure 32. They
were commenced November 16th, 1844. B, Baltimore; W, Washington.
[Illustration: FIG. 32.]
_First Game of Chess._
W 12 to 28
B 53 “ 37
W 6 “ 30
B 51 “ 46
W 7 “ 22
B 52 “ 36
W 28 “ 36
B 46 “ 36
W 30 “ 18
B 63 “ 46
W 13 “ 20
B 56 “ 41
W 9 “ 24
B 58 “ 43
W castles
B 59 to 45
W 14 “ 19
B 45 “ 51
W 3 “ 21
B 61 “ 45
W 22 “ 5
B 55 “ 39
W 2 “ 17
B 49 “ 48
W 19 “ 30
B 36 “ 29
W 21 “ 13
B 39 “ 26
W 11 to 29
B 26 “ 24
W 10 “ 23
B 62 “ 26
W 4 “ 3
B 43 “ 40
W 30 “ 35
B 45 “ 42
W 7 “ 9
B 40 “ 23
W 5 “ 14
B 23 “ 6
W 3 “ 6
B castles
60 to 62
& 64 “ 61
W 17 to 30
B 26 “ 38
W 14 “ 5
B 57 “ 58
W 30 “ 45c
B 51 “ 45
W 35 “ 45
B 42 “ 23c
W 9 “ 8
B 61 “ 52
W 27 “ 37
B 24 “ 9
B 18 “ 36
B 23 “ 7
W gives up.
_Second Game._
B 52 to 36
W 11 “ 27
B 62 “ 38
W 13 “ 20
B 53 “ 44
W 7 “ 22
B 51 “ 35
W 12 “ 21
B 59 “ 45
W 14 to 19
B 49 “ 48
W 9 “ 24
B 56 “ 40
W 10 “ 23
B 58 “ 43
W 2 “ 13
B 63 “ 46
W 4 “ 14
B 50 to 34
W 21 “ 28
B 36 “ 28
W 20 “ 28
B 38 “ 42
W 22 “ 25
B 42 “ 56
W 6 “ 20
B 43 “ 52
W 14 to 4
B 45 “ 27
W castles
B 27 “ 21c
W 7 “ 8
B 61 “ 39
W 13 “ 22
B 39 “ 41
W 3 “ 21
B 41 to 21
W 6 “ 5
B 21 “ 11
W 4 “ 45
B 64 “ 62
W 1 “ 4
B 52 “ 37
W 22 “ 37
B 46 “ 37
W 45 “ 37
B castles
W 4 to 2
B 62 “ 61
W 37 “ 27
B 11 “ 14
W 5 “ 3
B 14 “ 12
W 27 “ 6
B 12 “ 21
W 6 “ 5
B 3l “ 39
W 25 “ 22
B 39 to 53
W 3 “ 4
B 35 “ 30
W 4 “ 61
B 59 “ 61
W 24 “ 25
B 44 “ 37
W 22 “ 39
B 56 “ 42
W 2 “ 4
B 61 “ 60
W 5 “ 13
B 53 “ 35
W 39 “ 24
B 58 “ 57
W 13 “ 52
B 54 “ 43
W 8 “ 9
B 35 “ 21
W 52 “ 13
B 21 “ 47
W 13 “ 12
B 42 to 54
W 4 “ 52
B 57 “ 58
W 12 “ 13
B 48 “ 33
W 52 “ 45
B 47 “ 51
W 24 “ 11
B 60 “ 63
W 16 “ 17
B 63 “ 62
W 10 “ 24
B 62 “ 60
W 11 “ 4
B 54 “ 42
W 45 “ 52
B 51 “ 46
W 52 “ 45
B 46 “ 64
W 13 “ 36c
B 64 “ 36
W 28 “ 36
B 42 to 54
W 4 “ 21
B 55 “ 42
W 45 “ 47
B 43 “ 38
W 47 “ 34
B 38 “ 27
W 23 “ 27
B 37 “ 27
W 21 “ 30
B 42 “ 39
W 25 “ 39
B 54 “ 42
W 24 “ 44c
B 58 “ 57
W 30 “ 37
B 42 “ 28
W 37 “ 54c
B 57 “ 55
W 54 “ 45
B gives up.
_Improvement in the Magneto Electric Machine, and Application of this
Instrument to operate the Magnetic Telegraph._
The magneto electric machine was originally contrived by Mr. Saxton,
soon after the announcement of the interesting discovery of Faraday,
that magnetism was capable of exciting electricity. The conditions
necessary for obtaining electricity in this way were, chiefly, the
disturbance of magnetic forces in a bar of soft iron surrounded by
coils of wire. A number of mechanical contrivances were resorted to,
in order to effect this disturbance, by causing the bar of iron, thus
surrounded, to approach to and recede from the poles of powerful
magnets; but the ingenuity of Mr. Saxton far exceeded them all, by
giving to the coils and enclosed bar a rotary movement about the poles
of a U-form magnet. This instrument afforded bright sparks and strong
shocks; but the currents of electricity thus obtained could not be
converted to any useful purpose, as, in each half revolution of the
coils, the currents were in opposite directions. In 1838, Professor
Page published in Silliman’s Journal an account of an improved
form of the machine, doing away with many existing objections, and
furthermore rendering it at once a useful instrument, by a contrivance
for conducting these opposing currents into one channel or direction,
which part of the contrivance was called the _unitrep_. The current
produced in this way was capable of performing the work to a certain
extent, of the power developed by the galvanic battery; and the machine
was found adequate to the furnishing of shocks for medical purposes,
for exhibiting the decomposition of water, furnishing the elements
oxygen and hydrogen at their respective poles, and producing definite
electro-chemical results. These two last results could not be obtained
without the aid of the unitrep. But, with this improvement, the
instrument was still wanting in one property of the galvanic battery,
viz. that property which chemists call quantity, or that power upon
which depends its ability to magnetize, and also to heat platinum
wires. This last property has been given to the machine by the recent
contrivance of Professor Page. The machine, in its novel construction,
under his improvement, developed what is called, by way of distinction,
the current of intensity, but had a very feeble magnetizing power. By
a peculiar contrivance of the coils, (not to be made public until his
rights are in some way secured,) the current of quantity is obtained
in its maximum, while, at the same time, the intensity is so much
diminished that it gives scarcely any shock, and decomposes feebly. It
has been successfully tried with the magnetic telegraph of Professor
Morse, and operates equally well with the battery. It affords, by
simply turning a crank attached to the machine, a constant current
of galvanic electricity; and as there is no consumption of material
necessary to obtain this power, it will doubtless supersede the use
of the galvanic battery, which, in the event of constant employment,
would be very expensive, from the waste of zinc, platinum, acids,
mercury, and other materials used in its construction. It particularly
recommends itself for magnetizing purposes, as it requires no knowledge
of chemistry to insure the result, being merely mechanical in its
action, and is always ready for action without previous preparation;
the turning of a crank being the only requisite when the machine is
in order. It is not liable to get out of order; does not diminish
perceptibly in power when in constant use, and actually gains power
when standing at rest. It will be particularly gratifying to the man of
science, as it enables him to have always at hand a constant power for
the investigation of its properties, without any labor of preparation.
We notice among the beautiful results of this machine, that it charges
an electro magnet so as to sustain a weight of 1,000 pounds, and
it ignites to a white heat large platinum wires, and may be used
successfully for blasting at a distance; and should Government ever
adopt any such system of defence as to need the galvanic power, it must
supersede the battery in that case. Professor Page demonstrates, by
mathematical reasoning, that the new contrivance of the coils affords
the very maximum of quantity to be obtained by magnetic excitation.
_Report of Commissioner of Patents, for 1844._
REPORTS TO CONGRESS ON THE SUBJECT OF ELECTRO MAGNETIC TELEGRAPHS.
_Letter from the Secretary of the Treasury, transmitting a
Report upon the subject of a System of Telegraphs for
the United States. December 11, 1837._
TREASURY DEPARTMENT, _December 6, 1837_.
SIR: I have the honor to present this report,
in compliance with the following resolution, which passed
the House of Representatives on the 3d of February last,
viz. “_Resolved_, That the Secretary of the Treasury be
requested to report to the House of Representatives, at its
next session, upon the propriety of establishing a system
of telegraphs for the United States.” Immediately after its
passage I prepared a circular, with the view of procuring,
from the most intelligent sources, such information as would
enable Congress, as well as the Department, to decide upon
the propriety of establishing a system of telegraphs.
It seemed also important to unite with the inquiry
the procurement of such facts as might show the expense
attending different systems; the celerity of communication
by each; and the useful objects to be accomplished by their
adoption.
A copy of the circular is annexed, (1)
The replies have been numerous, and many of them are very
full and interesting. Those deemed material are annexed,
numbered 2 to 18, inclusive.
From those communications, and such other investigations
as the pressure of business has enabled me to make, I am
satisfied that the establishment of a system of telegraphs
for the United States would be useful to commerce as well as
the Government. It might most properly be made appurtenant
to the Post Office Department, and, during war, would prove
a most essential aid to the military operations of the
country.
The expense, attending it is estimated carefully in some
of the documents annexed; but it will depend much upon the
kind of system adopted: upon the extent and location
of the lines first established; and the charges made to
individuals for communicating information through it which
may not be of a public character.
On these points, as the Department has not been requested
to make a report, no opinion is expressed; but information
concerning them was deemed useful as a guide in deciding
on the propriety of establishing telegraphs, and was,
therefore, requested in the circular before mentioned.
Many useful suggestions in relation to the subject will be
found in the correspondence annexed, and in the books there
referred to.
The Department would take this occasion to express, in
respect to the numerous gentlemen whose views are now
submitted to Congress, its high appreciation and sincere
acknowledgments for the valuable contributions they have
made on a subject of so much interest.
I remain, very respectfully,
Your obedient servant,
LEVI WOODBURY,
_Secretary of the Treasury_.
The Hon. J. K. POLK,
_Speaker of the House of Representatives_.
No. 1.
_Circular to certain Collectors of the Customs, Commanders of
Revenue Cutters, and other persons._
TREASURY DEPARTMENT, _March 10, 1837_.
With the view of obtaining information in regard to “the
propriety of establishing a system of telegraphs for the
United States,” in compliance with the request contained
in the annexed resolution of the House of Representatives,
adopted at its last session, I will thank you to furnish the
Department with your opinion upon the subject. If leisure
permits, you would oblige me by pointing out the manner,
and the various particulars, in which the system may be
rendered most useful to the Government of the United States
and the public generally. It would be desirable, if in your
power, to present a detailed statement as to the proper
points for the location, and distance of the stations from
each other, with general rules for the regulation of the
system, together with your sentiments as to the propriety
of connecting it with any existing department of the
Government, and some definite idea of the rapidity with
which intelligence could ordinarily, and also in urgent
cases, be communicated between distant places. I wish you to
estimate the probable expense of establishing and supporting
telegraphs, upon the most approved system, for any given
distance, during any specified period.
It would add to the interest of the subject if you would
offer views as to the practicability of uniting with a
system of telegraphs for communication in clear weather
and in the day time, another for communication in fogs, by
cannon, or otherwise; and in the night, by the same mode, or
by rockets, fires, &c.
I should be gratified by receiving your reply by the first
of October next.
LEVI WOODBURY,
_Secretary of the Treasury_.
No. 2.
_Letter from S. F. B. Morse, to the
Secretary of the Treasury._
NEW YORK CITY UNIVERSITY, _Sept. 27, 1837_.
DEAR SIR: In reply to the inquiries which you
have done me the honor to make, in asking my opinion “of
the propriety of establishing a system of telegraphs
for the United States,” I would say, in regard to the
general question, that I believe there can scarcely be two
opinions, in such a community as ours, in regard to the
advantage which would result, both to the Government and
the public generally, from the establishment of a system
of communication by which the most speedy intercourse may
be had between the most distant parts of the country. The
_mail system_, it seems to me, is founded on the universally
admitted principle, that the greater the speed with which
intelligence can be transmitted from point to point, the
greater is the benefit derived to the whole community. The
only question that remains, therefore, is, what system is
best calculated, from its completeness and cheapness, to
effect this desirable end?
With regard to telegraphs constructed on the ordinary
principles, however perfected within the limits in which
they are necessarily confined, the most perfect of them
are liable to one insurmountable objection—_they are
useless the greater part of the time_. In foggy weather,
and ordinarily during the night no intelligence can be
transmitted. Even when they can transmit, much time is
consumed in communicating but little, and that little not
always precise.
Having invented an entirely new mode of telegraphic
communication, which, so far as experiments have yet
been made with it, promises results of almost marvellous
character, I beg leave to present to the Department a brief
account of its chief characteristics.
About five years ago, on my voyage home from Europe,
the electrical experiment of Franklin, upon a wire some
four miles in length was casually recalled to my mind in a
conversation with one of the passengers, in which experiment
it was ascertained that the electricity travelled through
the whole circuit in a time not appreciable, but apparently
instantaneous. _It immediately occurred to me, that if the
presence of electricity could be made_ VISIBLE
_in any desired part of this circuit, it would not be
difficult to construct a_ SYSTEM OF SIGNS _by which
intelligence could be instantaneously transmitted._ The
thought, thus conceived, took strong hold of my mind in the
leisure which the voyage afforded, and I planned a system
of signs and an apparatus to carry it into effect. I cast
a species of type, which I had devised for this purpose,
the first week after my arrival home; and although the
rest of the machinery was planned, yet, from the pressure
of unavoidable duties, I was compelled to postpone my
experiments, and was not able to test the whole plan until
within a few weeks. The result has realized my most sanguine
expectations.
As I have contracted with Mr. Alfred Vail to have a
complete apparatus made to demonstrate at Washington by the
1st of January, 1838, the practicability and superiority
of my mode of telegraphic communication by means of
electro magnetism, (an apparatus which I hope to have the
pleasure of exhibiting to you,) I will confine myself in
this communication to a statement of its peculiar advantages.
_First._ The _fullest and most precise information_
can be almost instantaneously transmitted between any
two or more points, between which a wire conductor
is laid: that is to say, no other time is consumed
than is necessary to write the intelligence to
be conveyed, and to convert the words into the
telegraphic numbers. The numbers are then transmitted
nearly instantaneously, (or if I have been rightly
informed in regard to some recent experiments in the
velocity of electricity, _two hundred thousand miles
in a second_,) to any distance, where the numbers
are immediately recognised, and reconverted into the
words of the intelligence.
_Second._ The same full intelligence can be
communicated _at any moment irrespective of the time
of day or night, or state of the weather._ This
single point establishes its superiority to all other
modes of telegraphic communication now known.
_Third._ The whole apparatus will occupy but
_little space_, (scarcely six cubic feet, probably
not more than four;)[11] and it may, therefore, be
placed without inconvenience, in any house.
_Fourth._ The _record of intelligence is made in
a permanent manner and in such a form_ that it can
be at once bound up in _volumes_ convenient for
reference, if desired.
_Fifth._ _Communications are secret_ to all but the
persons for whom they are intended.
[11] It now occupies a space 10 inches long, 8 inches high, and 5 wide.
These are the chief advantages of the Electro Magnetic
Telegraph over other kinds of telegraphs, and which must
give it the preference, provided the expense and other
circumstances are reasonably favorable.
The newness of the whole plan makes it not so easy to
estimate the expense, but an _approach_ to a correct
estimate can be made.
The principal expense will be the first cost of the wire
or metallic conductors, (consisting of four lengths,) and
the securing them against injury. The cost of a single
copper wire ¹/₁₆ of an inch diameter, (and it should not be
of less dimensions,) for 400 miles, was recently estimated
in Scotland to be about £1,000 sterling, including the
solderings of the wire together; that is, about $6 per mile
for one wire, or $24 per mile for the four wires. I have
recently contracted for twenty miles of copper wire, No. 18,
at 40 cents per pound. Each pound, it is estimated, contains
93 feet, which gives a result coinciding with the Scotch
estimate, if $1.60 per mile be added for solderings.
The preparation of the wire for being laid, (if in the
ground,) comprehends the _clothing of the wires_ with an
insulating or non-conducting substance; the _encasing them
in wood_, _clay_, _stone_, _iron_, or _other metal_; and
the _trenching_ of the earth to receive them. In this part
of the business I have no experience to guide me, the whole
being altogether new. I can, therefore, only make at present
a rough estimate. Iron tubes enclosing the wires, and filled
in with pitch and resin, would probably be the most eligible
mode of securing the conductors from injury, while, at the
same time, it would be the most costly. Iron tubes of 1½
inch diameter, I learn, can be obtained at Baltimore, at
28 cents per foot. The _trenching_ will not be more than
three cents for 2 feet, or about $75 per mile. This estimate
is for a trench 3 feet deep and 1½ wide. There is no
_grading_; the trench may follow the track of any road, over
the highest hills or lowest valleys. Across rivers, with
bridges, the circuit may easily be carried, enclosed beneath
the bridge. Where the stream, is wide, and no bridge, the
circuit, enclosed in lead, may be sunk to the bottom.
If the circuit is laid through the air, the first cost
would doubtless be much lessened. This plan of making
the circuit has some advantages, but there are also some
disadvantages; the chief of which latter is, that, being
always in sight, the temptation to injure the circuit to
mischievously disposed persons, is greater than if it were
buried out of sight beneath their feet. As an offset,
however, to this, an injury to the circuit is more easily
detected. With regard to danger from wantonness, it may be
sufficient to say, that the same objection was originally
made in the several cases, successively, of water-pipes,
gas-pipes, and railroads; and yet we do not hear of
wantonness injuring any of these. Stout spars of some thirty
feet in height, well planted in the ground, and placed
about 350 feet apart, would, in this case, be required,
along the tops of which the circuit might be stretched.
Fifteen such spars would be wanted to a mile. This mode
would be as cheap, probably, as any other, unless the laying
of the circuit in water should be found to be most eligible.
A series of experiments to ascertain the practicability
of this mode, I am about to commence with Professor Gale,
of our university, a gentleman of great science, and to whose
assistance, in many of my late experiments, I am greatly
indebted. We are preparing a circuit of twenty miles. The
result of our experiments I will have the honor of reporting
to you.
The other machinery, consisting of the apparatus for
transmitting and receiving the intelligence, can be made at
a very trifling cost. The only parts of the apparatus that
waste or consume materials, are the batteries, which consume
_acid_ and _zinc_, and the register, which consumes _paper_
for recording, and _pencils_ or _ink_ for marking.
The cost of _printing_, in the first instance, of a
_telegraphic dictionary_,[12] should perhaps also be taken
into the account, as each officer of the Government, as well
as many others, would require a copy, should this mode of
telegraphic communication go into effect. This dictionary
would contain a vocabulary of all the words in common use in
the English language, with the numbers regularly affixed to
each word.
[12] Mr. Francis O. J. Smith has recently published a Secret
Corresponding Vocabulary adapted to this purpose.
The stations in the case of this telegraph may be as
numerous as are desired; the only additional expense for
that purpose being the adding of the transmitting and
receiving apparatus to each station.
The cost of supporting a system of telegraphs on this
plan, (when a circuit is once established,) would, in my
opinion, be much less than on the common plans; yet, for
want of experience in this mode, I would not affirm it
positively.
As to “the propriety of connecting the system of
telegraphs with any existing department of Government,” it
would seem most natural to connect a telegraphic system
with the Post Office Department; for, although it does not
carry a mail, yet it is another mode of accomplishing the
principal object for which the mail is established, to wit:
the rapid and regular transmission of intelligence. If my
system of telegraphs should be established, it is evident
that the telegraph would have but little rest day or night.
The advantage of communicating intelligence instantaneously
in hundreds of instances of daily occurrence, would warrant
such a rate of _postage_, (if it may be so called,) as would
amply defray all expenses of the first cost of establishing
the system, and of guarding it, and keeping it in repair.
As every word is numbered, an obvious mode of rating might
be, a _charge of a certain amount on so many numbers_. I
presume that five words can certainly be transmitted in a
minute; for, with the imperfect machinery I now use, I have
recorded at that rate, at the distance of half a mile.
In conclusion, I would say, that if the perfecting of
this new system of telegraphs (which may justly be called
the American Telegraph, since I can establish my claims
to priority in the invention) shall be thought of public
utility, and worthy the attention of Government, I shall be
ready to make any sacrifice of personal service and of time
to aid in its accomplishment.
In the mean time I remain, sir, with sincere respect and
high personal esteem,
Your most obedient, humble servant,
SAML. F. B. MORSE.
HON. LEVI WOODBURY,
_Secretary of the Treasury_.
No. 3.
_Letter from S. F. B. Morse to the Secretary of the Treasury._
UNIVERSITY OF THE CITY OF NEW YORK,
_November 28, 1837_.
MY DEAR SIR: In my letter to you in answer to
the circular respecting telegraphs, which you did me the
honor to send me, I promised to advise you of the result of
some experiments about to be tried with my electro magnetic
telegraph. I informed you that I had succeeded in marking
permanently and intelligibly at the distance of _half a
mile_.
Professor Gale, of our university, and Mr. Alfred Vail,
of the Speedwell iron-works, near Morristown, New Jersey,
are now associated with me in the scientific and mechanical
parts of the invention. We have procured several miles of
wire, and I am happy to announce to you that our success has
thus far, been complete. At a distance of _five miles_, with
a common Cruikshank’s battery of 87 plates, (4 by 3½ inches
each plate,) the marking was as perfect on the register
as in the first instance of half a mile. We have recently
added _five miles more_, making in all _ten miles_, with the
_same result_; and we have now no doubt of its effecting a
_similar result_ at _any distance_.
I also stated to you, sir, that machinery was in progress
of making, with which, so soon as it should be completed,
I intended to proceed to Washington, to exhibit the powers
of the invention before you and other members of the
Government. I had hoped to be in Washington before the
session of Congress, but I find that the execution of new
machinery is so uncertain in its time of completion, that I
shall be delayed, probably, until the beginning of the year.
What I wish to learn from you, sir, is, “_How late in the
session can I delay my visit, and yet be in season to meet
the subject of telegraphs, when it shall be presented by
your report to Congress?_”
I am anxious, of course, to show as perfect an instrument
as possible, and would wish as much time for the purpose
of perfecting it as can be allowed without detriment to my
interests as an applicant for the attention of Government to
the best plan of a telegraph.
I am, my dear sir, with the greatest respect and personal
esteem,
Your most obedient servant,
SAML. F. B. MORSE.
HON. LEVI WOODBURY,
_Secretary of the Treasury_.
No. 4.
[From the New York Journal of Commerce.]
We have received the following note and diagram, with the
explanation of the latter, from Mr. Morse:
_To the Editors of the Journal of Commerce:_
GENTLEMEN: You had the kindness to assert, a few
days ago, my claim to the invention of the _electro magnetic
telegraph_, for which I thank you. As to the priority of my
invention, entirely planned and for the most part executed
as it was nearly five years ago, I can adduce the amplest
proof.
You announced that I was preparing a short _circuit_, to
show to my friends the operation of the telegraph. This
circuit I have completed, of the length of 1,700 feet, or
about one-third of a mile; and on Saturday, the 2d instant,
in presence of Professors Gale and Torrey of this city, and
Professor Daubeny of the Oxford (English) University, and
several other gentlemen, I tried a preliminary experiment
with the register. It recorded the intelligence sufficiently
perfect to establish the practicability of the plan, and the
superior simplicity of my mode of communication, over any of
those proposed by the professors in Europe.
It will be observed that no account has reached us that
any of the foreign proposed electric telegraphs have as
yet succeeded in transmitting intelligible communications;
but it is merely asserted of the most advanced experiment,
(the one in London,) that “by means of five wires,” &c.
intelligence “_may be_ conveyed.” I have the gratification
of sending you a specimen of the writing of my telegraph,
the actual transmission of a communication made this
morning, in a more complete manner than on Saturday, and
through the distance of one-third of a mile.
Thinking it may be gratifying to your readers to see the
kind of writing which it performs, I have had it engraved
for you, accompanied with an explanation.
Your obedient servant,
SAML. F. B. MORSE.
_N. Y. City University, September 4, 1837._
No. 5.
_Specimen of Telegraphic Writing made by means of electricity
at the distance of one-third of a mile._
[Illustration]
The _words_ in the diagram were the intelligence
transmitted.
The _numbers_ (in this instance arbitrary) are the numbers
of the words in a telegraphic dictionary.
The _points_ are the markings of the register, each point
being marked every time the electric fluid passes.
The register marks but one kind of mark, to wit, (V.) This
can be varied two ways. By intervals, thus, (V VV VVV,)
signifying one, two, three, &c., and by reversing, thus, (Λ)
Examples of both these varieties are seen in the diagram.
The single numbers are separated by short, and the whole
numbers by _long intervals_.
To illustrate by the diagram: the word “successful” is
first found in the dictionary, and its telegraphic number,
215, is set up in a species of type prepared for the
purpose, and so of the other words. The type then operate
upon the machinery, and serve to regulate the times and
intervals of the passage of electricity. Each passage of the
fluid causes a pencil at the extremity of the wire to mark
the points as in the diagram.
To read the marks, count the points at the bottom of each
line. It will be perceived that two points come first,
separated by a _short_ interval from the next point. Set 2
beneath it. Then comes one point, likewise separated by a
_short_ interval. Set 1 beneath it. Then come five points.
Set 5 beneath them. But the interval in this case is a
_long_ interval: consequently, the three numbers comprise
the whole number, 215.
So proceed with the rest, until the numbers are all set
down. Then, by referring to the telegraphic dictionary,
the words corresponding to the numbers are found, and the
communication read. Thus it will be seen that, by means
of the changes upon _ten_ characters, all words can be
transmitted. But there are _two points_ reversed in the
lower line. These are the _eleventh_ character, placed
before a number, to signify that it is to be read as a
_number_, and not as the representative of a word.
No. 6.
Mr. SMITH, from the Committee on Commerce,
made the following Report,
April 6th, 1838.
_The Committee on Commerce to whom the subject was referred,
have had the same under consideration, and report:_
On the 3d of February, 1837, the House of Representatives
passed a resolution requesting the Secretary of the Treasury
to report to the House, at its present session, upon the
propriety of establishing a system of telegraphs for the
United States.
In pursuance of this request, the Secretary of the
Treasury, at an early day after the passage of said
resolution, addressed a circular of inquiry to numerous
scientific and practical individuals in different parts of
the Union; and, on the 6th of December last, reported the
result of this proceeding to the House.
This report of the Secretary imbodies many useful
suggestions on the necessity and practicability of a system
of telegraphic despatches, both for public and individual
purposes; and the committee cannot doubt that the American
public is fully prepared, and even desirous, that every
requisite effort be made on the part of Congress to
consummate an object of so deep interest to the purposes of
Government in peace and in war, and to the enterprise of the
age.
Amid the suggestions thus elicited from various sources,
and imbodied in the before-mentioned report of the Secretary
of the Treasury, a plan for an electro magnetic telegraph
is communicated by Professor Morse, of the University of
the city of New York, pre-eminently interesting, and even
wonderful. See Report, No. 2.
This invention consists in the application, by mechanism,
of galvanic electricity to telegraphic purposes, and is
claimed by Professor Morse and his associates as original
with them; and being so, in fact, as the committee believe,
letters-patent have been secured, under the authority of
the United States, for the invention. It has, moreover,
been subjected to the test of experiment, upon a scale of
ten miles distance, by a select committee of the Franklin
Institute of the city of Philadelphia, and reported upon
by that eminently high tribunal in the most favorable and
confident terms. An abstract from the report thus made is
hereunto annexed. No. 7.
In additional confirmation of the merits of his proposed
system of telegraphs, Professor Morse has exhibited it in
operation (by a coil of metallic wire measuring about ten
miles in length, rendering the action equal to a telegraph
of half that distance) to the Committee on Commerce of
the House of Representatives, to the President of the
United States, and the several heads of Departments, to
members of Congress generally, who have taken interest in
the examination, and to a vast number of scientific and
practical individuals from various parts of the Union; and
all concur, it is believed, and without a dissenting doubt,
in admiration of the ingenious and scientific character of
the invention, and in the opinion that it is successfully
adapted to the purposes of telegraphic despatches, and
in a conviction of its great and incalculable practical
importance and usefulness to the country, and ultimately to
the whole world.
But it would be presumptuous in any one, (and the inventor
himself is most sensible of this,) to attempt, at this
stage of the invention, to calculate in anticipation, or to
hold out promises of what its whole extent of capacity for
usefulness may be, in either a political, commercial, or
social point of view, if the electrical power upon which it
depends for successful action shall prove to be efficient,
as is now supposed it will, to carry intelligence through
any of the distances of 50, 100, 500, or more miles now
contemplated. No such attempt, therefore, will be indulged
in this report. It is obvious, however, that the influence
of this invention over the political, commercial, and social
relations of the people of this widely-extended country,
looking to nothing beyond, will, in the event of success,
of itself amount to a revolution unsurpassed in moral
grandeur by any discovery that has been made in the arts and
sciences, from the most distant period to which authentic
history extends, to the present day. With the means of
almost instantaneous communication of intelligence between
the most distant points of the country, and simultaneously
between any given number of intermediate points which this
invention contemplates, space will be, to all practical
purposes of information, completely annihilated between the
States of the Union, as also between the individual citizens
thereof. The citizen will be invested with, and reduce
to daily and familiar use, an approach to the HIGH
ATTRIBUTE OF UBIQUITY, in a degree that the human mind
until recently, has hardly dared to contemplate seriously
as belonging to human agency, from an instinctive feeling
of religious reverence and reserve on a power of such awful
grandeur.
Referring to the annexed report of the Franklin Institute,
already adverted to, and also to the letters of Professor
Morse, marked 2, 8 and 9, for other details of the
superiority of this system of telegraphs over all other
methods heretofore reduced to practice by any individual or
Government, the committee agree, unanimously, that it is
worthy to engross the attention and means of the Federal
Government, to the full extent that may be necessary to
put the invention to the most decisive test that can be
desirable. The power of the invention, if successful, is so
extensive for good and for evil, that the Government alone
should possess the right to control and regulate it. The
mode of proceeding to test it, as suggested, as also the
relations which the inventor and his associates are willing
to recognise with the Government on the subject of the
future ownership, use, and control of the invention, are
succinctly set forth in the annexed letters of Professor
Morse, marked 8 and 9.
The probable outlay of an experiment upon a scale equal
to fifty miles of telegraph, and equal to a circuit of
double that distance, is estimated at $30,000. Two-thirds of
this expenditure will be for material, which, whether the
experiment shall succeed or fail, will remain uninjured, and
of very little diminished value below the price that will be
paid for it.
The estimates of Professor Morse, as will be seen by
his letter, marked 9, amount to $26,000; but, to meet any
contingency not now anticipated, and to guard against any
want of requisite funds in an enterprise of such moment to
the Government, to the people, and to the scientific world,
the committee recommend an appropriation of $30,000, to
be expended under the direction of the Secretary of the
Treasury; and to this end submit herewith a bill.
It is believed by the committee that the subject is one of
such universal interest and importance, that an early action
upon it will be deemed desirable by Congress, to enable the
inventor to complete his trial of the invention upon the
extended scale contemplated, in season to furnish Congress
with a full report of the result during its present session,
if that shall be practicable.
All which is respectfully submitted.
FRANCIS O. J. SMITH, JAS. M. MASON,
S. C. PHILLIPS, JOHN T. H. WORTHINGTON,
SAMUEL CUSHMAN, WM. H. HUNTER,
JOHN I. DE GRAFF, GEORGE W. TOLAND,
EDWARD CURTIS,
_Committee on Commerce, U. S. H. R._
No. 7.
HALL OF THE FRANKLIN INSTITUTE, _Feb. 8, 1838_.
_Report of the Franklin Institute Philadelphia._
The sub-committee, from the committee of science and arts,
appointed to examine the electro magnetic telegraph of
Professor Samuel F. B. Morse, report:
That this instrument was exhibited to them in the hall of
the Institute, and every opportunity given by Mr. Morse and
his associate, Mr. Alfred Vail, to examine it carefully,
and to judge of its operation; and they now present the
following as the result of their observations:
* * * * The operation of the telegraph, as exhibited to
us, was very satisfactory. The power given to the magnet at
the register, through a length of wire of ten miles, was
abundantly sufficient for the movements required to mark the
signals. The communication of this was instantaneous. The
time required to make the signals was as short at least, as
that necessary in the ordinary telegraphs. It appears to
this committee, therefore, that the possibility of using
telegraphs upon this plan, in actual practice, is not to be
doubted; though difficulties may be anticipated, which could
not be tested by the trials made with the model.
One of these relates to the insulation and protection of
the wires, which are to pass over many miles of distance,
to form the circuits between the stations. Mr. Morse
has proposed several plans: the last being to cover the
wires with cotton thread, then varnish them thickly with
gum-elastic, and enclose the whole in leaden tubes. More
practical and economical means will probably be devised; but
the fact is not to be concealed, that any effectual plan
must be very expensive.
Doubts have been raised as to the distance to which the
electricity of an ordinary battery can be made efficient;
but your committee think that no serious difficulty is
anticipated as to this point. The experiment with the wire
wound in a coil, may not, indeed, be deemed conclusive;
but one of the members of the committee assisted in an
experiment in which a magnet was very sensibly affected by a
battery of a single pair, through an insulated wire of two
and three-quarter miles in length, of which the folds were
four inches apart; and when a battery of ten pairs was used,
water was freely decomposed. An experiment is said to have
been made, with success, on the Birmingham and Manchester
rail road, through a circuit of thirty miles in length.
It may be proper to state, that the idea of using
electricity for telegraphic purposes has presented itself
to several individuals, and that it may be difficult
to settle among them the question of originality. The
celebrated Gauss has a telegraph of this kind in actual
operation, for communicating signals between the University
of Göttingen and his magnetic observatory in its vicinity.
Mr. Wheatstone, of London, has been for some time also
engaged in experiments on an electrical telegraph. But the
plan of Professor Morse is, so far as the committee are
informed, entirely different from any of those devised by
other individuals, all of which act by giving different
_directions_ to a magnetic needle; and would, therefore,
require several circuits of wire between all the stations.
In conclusion, the committee beg leave to state their
high gratification with the exhibition of Professor Morse’s
telegraph, and their hope that means may be given to him
to subject it to the test of an actual experiment, made
between stations at a considerable distance from each
other. The advantages which this telegraph would present,
if successful, over every kind heretofore used, make it
worthy the patronage of the Government. These are, that the
stations may be at a distance asunder, far exceeding that to
which all other telegraphs are limited; and that the signals
may be given at night, and in rains, snows, and fogs, when
other telegraphs fail.
R. M. PATTERSON, _Chairman_.
No. 8.
_From S. F. B, Morse, to the Hon. F. O. J. Smith._
WASHINGTON, _February 15, 1838_.
DEAR SIR: In consequence of the conversation
had with the committee on the subject of my telegraph, I
would state, that I think it desirable that an experiment,
on a somewhat extended scale, should first be made to test
both the practicability and the facility of communicating
intelligence for at least one hundred miles. The experiment
may proceed, as to cost, with perfect safety to the
Government. _First._ The wire for this distance, consisting
of four lengths, making a total of four hundred miles of
wire, might be obtained, and receive its covering of cotton
and other insulation. This length would amply suffice
to ascertain the law of the propulsive power of voltaic
electricity, and previous to any measures being taken
for burying it in the earth. So that, if any unforeseen
difficulty should occur fatal to its practicability, the
wire is not consumed or lost. If the expected success is
realized, then, _Second._ The preparation of the wire might
be commenced for burying in the earth, and, being found
complete through the whole route, the several portrules,
registers, batteries, &c., might be provided to put the
telegraph into complete action. This experiment of one
hundred miles would furnish the data from which to make the
estimates of a more general extension of the system. If no
insurmountable obstacles present themselves in a distance
of one hundred miles, none may be expected in one thousand
or in ten thousand miles; and then will be presented for
the consideration of the Government the propriety of
completely organizing the new telegraphic system as a part
of the Government, attaching it to some department already
existing, or creating a new one, which may be called for by
the accumulating duties of the present departments.
It is obvious, at the slightest glance, that this mode
of instantaneous communication must inevitably become an
instrument of immense power, to be wielded for good or for
evil, as it shall be properly or improperly directed. In the
hands of a company of speculators, who should monopolize
it for themselves, it might be the means of enriching the
corporation at the expense of the bankruptcy of thousands;
and even in the hands of Government alone, it might become
a means of working vast mischief to the republic. In
considering these prospective evils, I would respectfully
suggest a remedy which offers itself to my mind. Let the
sole right of using the telegraph belong, in the first
place, to the Government, who should grant, for a specified
sum or bonus, to any individual or company of individuals
who may apply for it, and under such restrictions and
regulations as the Government may think proper, the right
to lay down a way communication between any two points, for
the purpose of transmitting intelligence; and thus would be
promoted a general competition. The Government would have a
telegraph of its own, and have its modes of communicating
with its own officers and agents, independent of private
permission, or interference with and interruption to the
ordinary transmissions on the private telegraphs. Thus
there would be a system of checks and preventives of abuse,
operating to restrain the action of this otherwise dangerous
power, within those bounds which will permit only the good
and neutralize the evil. Should the Government thus take the
telegraph solely under its own control, the revenue derived
from the bonuses alone, it must be plain, will be of vast
amount. From the enterprising character of our countrymen,
shown in the manner in which they carry forward any new
project which promises private or public advantage, it is
not visionary to suppose that it would not be long ere the whole
surface of this country would be channelled for those _nerves_
which are to diffuse, with the speed of thought, a knowledge of
all that is occurring throughout the land; making, in fact,
_one neighborhood_ of the whole country.
If the Government is disposed to test this mode of
telegraphic communication by enabling me to give it a fair
trial for one hundred miles, I will engage to enter into no
arrangements to dispose of my rights as the inventor and
patentee for the United States, to any individual or company
of individuals, previous to offering it to the Government
for such a just and reasonable compensation as shall be
mutually agreed upon.[13]
I remain, sir, respectfully, your most obedient servant,
SAMUEL F. B. MORSE.
To the Hon. F. O. J. SMITH,
_Chairman of the Committee on Commerce
of the House of Representatives._
[13] It is proper that I should here state, that the patent-right is
now jointly owned, in unequal shares, by myself, Prof. Gale of New York
City University, and Messrs. Alfred and George Vail.
No. 9.
_Letter from S. F. B. Morse to Hon. F. O. J. Smith._
WASHINGTON, _February 22, 1838_.
DEAR SIR: I have endeavoured to approach a proper
estimate of the expense attendant on preparing a complete
telegraphic communication for some distance; and taking
into consideration the possibility that the experiment
may be conclusively tried before the close of the present
session of Congress, I have thought that an appropriation
for fifty miles of distance would test the practicability
of the telegraph quite as satisfactorily as one hundred,
because the obstacles necessary to be overcome would not be
more proportionally in fifty than in one hundred; while, at
the same time, the _double circuit_ necessary in the fifty
miles would give a _single circuit_ of one hundred for the
purpose of testing the effect of distance upon the passage
of electricity. Fifty miles would require a less amount
of appropriation, and the experiment could also be sooner
brought to a result.
Two hundred miles of wire, or wire for two circuits for
fifty miles of distance, including the covering of
the wire with cotton, at $100 per mile, $20,000
Other expenses of preparation of the wire, such as
caoutchouc, wax, resin, tar, with reels for winding,
soldering, &c., say $6 per mile, 1,200
Batteries and registers, with type, &c., for two
stations, and materials for experimenting on the
best modes of magnets at long distances, 800
Services of Professor Gale in the chemical department;
services of Mr. Alfred Vail in the mechanical
department; services of assistants in different
departments; my own services in superintending and
directing the whole—total 4,000
——————
Total, [14]$26,000
=======
This estimate is exclusive of expense necessary to lay
down the wire beneath the ground. This is unnecessary until
the previous preparations are found satisfactory.
I cannot say what time will be required for the completion
of the circuits for fifty miles. If the order could be
immediately given for the wire, I think all the other matter
connected with it might be completed so that every thing
would be in readiness in _three months_. Much will depend
on the punctuality with which contractors fulfil their
engagements in furnishing the wire and other apparatus.
I remain, sir, very respectfully, your obedient servant,
SAMUEL F. B. MORSE.
To the Hon. F. O. J. SMITH,
_Chairman of the Committee on Commerce_.
[14] This line could now be constructed for less than half the sum.
No. 10.
_Mr. Ferris, from the Committee on Commerce,
made the following Report, December 30, 1842._
That they regard the question, as to the general utility
of the telegraphic system, settled by its adoption by
the most civilized nations; and experience has fully
demonstrated the great advantages which may be derived
from its use. Its capability of speedily transmitting
intelligence to great distances, for national defence,
and for other purposes, where celerity is desirable,
is decidedly superior to any of the ordinary modes
of communication in use. By it, the first warning of
approaching danger, and the appearance of hostile fleets
and armies on our coasts and borders, may be announced
simultaneously at the most distant points of our
widely-extended empire, thus affording time and opportunity
for concentrating the military force of the country,
for facilitating military and naval movements, and for
transmitting orders suitable to the emergency.
In the commercial and social affairs of the community,
occasions frequently arise in which the speedy transmission
of intelligence may be of the highest importance for the
regulation of business transactions, and in relieving
the anxious solicitude of friends, as to the health and
condition of those in whose fortunes they feel an interest.
The practicability of establishing telegraphs on the
electric principle is no longer a question. Wheatstone, of
London, and his associates, have been more fortunate than
our American inventor, in procuring the means to put his
ingenious system into practical use for two or three hundred
miles, in Great Britain; and the movements of the cars on
the Blackwall rail road are at this time directed with
great economy, and perfect safety to life and property, by
means of his magnetic needle telegraph. If a system more
complicated and less efficient than the American telegraph
is operated for great distances in England, with such
eminent success and advantage, there can be no reasonable
doubt that, if the means be furnished for putting in
operation the system of Professor Samuel F. B. Morse, of
New York, the original inventor of the electro-magnetic
telegraph, the same, if not greater success, will be the
result. Your committee are of opinion that it is but justice
to Professor Morse, who is alike distinguished for his
attainments in science and excellence in the arts of design,
and who has patiently devoted many years of unremitting
study, and freely spent his private fortune, in inventing
and bringing to perfection a system of telegraphs which
is calculated to advance the scientific reputation of the
country, and to be eminently useful, both to the Government
and the people, that he should be furnished with the means
of competing with his European rivals.
Professor Morse bases his system upon the two following
facts in science:
First. That a current of electricity will pass to any
distance along a conductor connecting the two poles of a
voltaic battery or generator of electricity, and produce
visible effects at any desired points on that conductor.
Second. That magnetism is produced in a piece of soft iron
(around which the conductor, in its progress, is made to
pass) when the electric current is permitted to flow, and
that the magnetism ceases when the current of electricity
is prevented from flowing. This current of electricity is
produced and destroyed by breaking and closing the galvanic
circuit at the pleasure of the operator of the telegraph,
who in this manner directs and controls the operation
of a simple and compact piece of mechanism, styled the
register, which, at the will of the operator at the point of
communication, is made to record, at the point of reception,
legible characters, on a roll of paper put in motion at the
same time with the writing instrument. These characters the
inventor has arranged into a conventional _alphabet_, and
which is capable of being learned and used with very little
practice.
Professor Morse has submitted his telegraphic plan to the
severe scrutiny of European criticism; and the Academy of
Sciences, of Paris, the highest scientific tribunal in the
world, hailed it with enthusiasm and approbation, when its
operation was exhibited, and its principles explained by
their distinguished perpetual secretary, M. Arago.
It appears, from documents produced by Professor Morse,
that the thanks of several learned bodies in France were
voted to him for his invention, and the large medal of honor
was awarded to him by the Academy of Industry. It further
appears, that several other systems of telegraphs on the
electric plan (among which were Wheatstone’s, of London,
Steinheil’s, of Munich, and Masson’s, of Caen) had been
submitted at various times for the consideration of the
French Government, who appointed a commission to examine
and report on them all, at the head of which commission
was placed the administrator-in-chief of the telegraphs of
France, (M. Foy,) who, to a note to Professor Morse, thus
writes:
“I take a true pleasure in confirming to you in writing
that which I have already had the honor to say to you viva
voce—that I have prominently presented to Monsieur the
Minister of the Interior your electro magnetic telegraph,
as being the system which presents the best chance of a
practical application; and I have declared to him that, if
some trials are to be made with electric telegraphs, I do
not hesitate to recommend that they should be made with your
apparatus.”
Your committee, in producing further evidence of the
approbation by the scientific world of the system of
Professor Morse, would cite the letter of Professor Henry,
of Princeton College, well known for his eminent attainments
in electrical science, (marked 11,) in the appendix of this
report.
More recently, a committee, consisting of some of our most
distinguished scientific citizens, was appointed by the
American Institute of New York, to examine and report upon
this telegraph, who made the report (12) in the appendix.
In compliance with the recommendation of this report, the
Institute awarded to Professor Morse the gold medal.
Besides the evidence these testimonials furnish of the
excellence of Professor Morse’s system, your committee,
as well as the greater part of the members of both Houses
of Congress, have had a practical demonstration of the
operation of the electro magnetic telegraph, and have
witnessed the perfect facility and extraordinary rapidity
with which a message can be sent by means of it from one
extremity of the capitol to the other. This rapidity is not
confined in its effects to a few hundred feet, but science
makes it certain that the same effects can be produced, at
any distance on the globe, between any two given points
connected by the conductors.
Your committee have alluded to other electric telegraphs;
for, as is not uncommon in the birth of great inventions,
scientific minds have, at nearly the same period of time,
in various parts of Europe, conceived and planned electric
telegraphs; but it is a matter of national pride, that the
invention of the _first electro magnetic telegraph_, by
Professor Morse, as well as the _first conception_ of using
electricity as the means of transmitting intelligence, by
Doctor Franklin, is the offspring of American genius.
Your committee beg leave to refer to the letter of
Professor Morse, (marked 13,) in the appendix, to C. G.
Ferris, one of the committee, giving, at his request a brief
history of the telegraph since it was before Congress, in
1838, for some interesting information concerning it, and
for Professor Morse’s estimate of the probable expense of
establishing his system of telegraphs for thirty or forty
miles.
They would also refer to the House document, No. 15,
(December 6, 1837,) and to House report, No. 753, (April 6,
1838,) for valuable information on the subject of telegraphs.
Your committee invite special attention to that part
of Professor Morse’s letter which details the plan of
a _revenue_ which may be derived from his telegraphic
system, when established to an extent sufficient for the
purposes of commercial and general intelligence. From these
calculations, made upon safe data, it is probable that
an income would be derived from its use by merchants and
citizens more than sufficient to defray the interest of the
capital expended in its establishment. So inviting, indeed,
are the prospects of profit to individual enterprise,
that it is a matter of serious consideration, whether the
Government should not, on this account alone, seize the
present opportunity of securing to itself the regulation
of a system which, if monopolized by a private company,
might be used to the serious injury of the Post Office
Department, and which could not be prevented without such
an interference with the rights of the inventor and of the
stockholders as could not be sustained by justice or public
opinion.
After the ordeal to which the electro magnetic telegraph
system has been subjected, both in Europe and in America,
and the voice of the scientific world in its favor, it is
scarcely necessary for your committee to say that they have
the fullest confidence in Professor Morse’s plan, and they
earnestly recommend the adoption of it by the Government
of the United States. They deem it most fortunate that
no definite system of telegraphs should hitherto have
been adopted by the Government, since it enables them to
establish this improved system, which, in the opinion of
your committee, is decidedly superior to any other now in
use, possessing an advantage over telegraphs depending
on vision, inasmuch as it may be used both by night and
day, in all weathers, and in all seasons of the year, with
equal convenience; and, also, possessing an advantage
over electric telegraphs heretofore in use, inasmuch as
it records, in permanent legible characters on paper, any
communication which may be made by it, without the aid of
any agent at the place of recording, except the apparatus
which is put in motion at the point of communication.
Thus, the recording apparatus, called the register, may be
left in a closed chamber, where it will give notice of its
commencing to write, by a bell, and the communication may
be found, on opening the apartment. Possessing these great
advantages, and the means of communication not being liable
to interruption by the ordinary contingencies which may
impede or prevent the successful action of other telegraphs,
the advantages to be derived from it will soon be apparent
to the community, and it will become the successful rival of
the Post Office, when celerity of communication is desired,
and create a revenue from which this system of telegraphs
may be extended and ramified through all parts of the
country, without imposing any burden upon the people or
draughts on the treasury, beyond the outlay for its first
establishment.
As a first step towards the adoption of this system of
telegraphs by the Government, your committee recommend
the appropriation of thirty thousand dollars to be
expended under the direction of the Postmaster General, in
constructing a line of electro magnetic telegraphs, under
the superintendence of Professor Sam’l F. B. Morse, of
such length and between such points as shall fully test
its practicability and utility; and for this purpose they
respectfully submit the following bill:
_A bill to test the Practicability of Establishing a System
of Electro Magnetic Telegraphs by the United States._
_Be it enacted by the Senate and House of Representatives
of the United States in Congress assembled_, That the sum of
thirty thousand dollars be, and is hereby, appropriated, out
of any moneys in the treasury not otherwise appropriated,
for testing the capacity and usefulness of the system of
electro magnetic telegraphs invented by Samuel F. B. Morse,
of New York, for the use of the Government of the United
States, by constructing a line of said electro magnetic
telegraphs, under the superintendence of Professor Samuel F.
B. Morse, of such length and between such points as shall
fully test its practicability and utility; and that the same
shall be expended under the direction of the Postmaster
General, upon the application of said Morse.
SEC. 2. _And be it further enacted_, That the
Postmaster General be, and he is hereby, authorized to pay,
out of the aforesaid thirty thousand dollars, to the said
Samuel F. B. Morse, and the persons employed under him, such
sums of money as he may deem to be a fair compensation for
the services of the said Samuel F. B. Morse and the persons
employed under him, in constructing and in superintending
the construction of the said line of telegraphs authorized
by this bill.
No. 11.
_Letter from Professor Henry to Professor Morse._
PRINCETON COLLEGE, _February 24, 1842_.
MY DEAR SIR: I am pleased to learn that you have
again petitioned Congress in reference to your telegraph,
and I most sincerely hope that you will succeed in
convincing our representatives of the importance of the
invention. In this you may, perhaps, find some difficulty,
since, in the minds of many, the electro magnetic telegraph
is associated with the various chimerical projects
constantly presented to the public, and particularly
with the schemes, so popular a year or two ago, for the
application of electricity as moving power in the arts. I
have asserted, from the first, that all attempts of this
kind are premature, and made without a proper knowledge
of scientific principles. The case is, however, entirely
different in regard to the electro magnetic telegraph.
_Science is now fully ripe for this application_, and I have
not the least doubt, if proper means be afforded, of the
perfect success of the invention.
The idea of transmitting intelligence to a distance by
means of electrical action, has been suggested by various
persons, from the time of Franklin to the present; but
until within the last few years, or since the principal
discoveries in electro magnetism, all attempts to reduce
it to practice were necessarily unsuccessful. The mere
suggestion, however, of a scheme of this kind is a matter
for which little credit can be claimed, since it is one
which would naturally arise in the mind of almost any person
familiar with the phenomena of electricity; but the bringing
it forward at the proper moment when the developments of
science are able to furnish the means of certain success,
and the devising a plan for carrying it into practical
operation, are the grounds of a just claim to scientific
reputation as well as to public patronage.
About the same time with yourself, Professor Wheatstone,
of London, and Dr. Steinheil, of Germany, proposed plans of
the electro magnetic telegraph, but these differ as much
from yours as the nature of the common principle would well
permit; and unless some essential improvements have lately
been made in these European plans, I should prefer the one
invented by yourself.
With my best wishes for your success, I remain, with much
esteem yours, truly,
JOSEPH HENRY.
PROFESSOR MORSE.
No. 12.
_Report of the American Institute on the
Electro Magnetic Telegraph._
NEW YORK, _September 12, 1842_.
The undersigned, the committee of arts and sciences of the
American Institute, respectfully report:
That, by virtue of the power of adding to their numbers,
they called to their aid the gentlemen whose names are
hereunto annexed, with those of the original members of
the committee, and proceeded to examine Professor Morse’s
electro magnetic telegraph.
Having investigated the scientific principles on which
it is founded, inspected the mechanism by which these
principles are brought into practical operation, and seen
the instruments in use in the transmission and return of
various messages, they have come to the conclusion that
it is admirably adapted to the purposes for which it is
intended, being capable of forming words, numbers, and
sentences, nearly as fast as they can be written in ordinary
characters, and of transmitting them to great distances with
a velocity equal to that of light. They, therefore, beg
leave to recommend the telegraph of Professor Morse for such
testimonials of the approbation of the American Institute
as may in its judgment be due to a most important practical
application of high science, brought into successful
operation by the exercise of much mechanical skill and
ingenuity.
All which is respectfully submitted.
JAMES RENWICK, LL. D.,
_Prof. Chem. and Nat. Phil., Columbia Col., N. Y._
JOHN W. DRAPER, M. D.,
_Prof. Chem. and Min., University, city of New York._
WILLIAM H. ELLET, M. D.
_Prof. Chem., &c. Col. of Columbia, S. C._
JAMES R. CHILTON, M. D.,
_Chem., &c., New York._
G. C. SCHAEFFER,
_Associate Prof. Chem., Columbia Col., N. Y._
EDWARD CLARK.
CHARLES A. LEE, M. D.
Extract from the minutes of the Institute:
_Resolved_, That the report be accepted, adopted, and
referred to the premium committee, and that the recording
secretary be directed to publish the same, at the expense of
the Institute.
No. 13.
_Letter from S. F. B. Morse to the Hon. C. G. Ferris._
NEW YORK, _December 6, 1842_.
DEAR SIR: In compliance with your request, I give
you a slight history of my electro magnetic telegraph, since
it was presented for the consideration of Congress, in the
year 1838.
During the session of the 25th Congress, a report was made
by the Committee on Commerce of the house, which concluded
by unanimously submitting a bill appropriating $30,000
for the purpose of testing my system of electro magnetic
telegraphs. The pressure of business at the close of that
session prevented any action being taken upon it.
Before the session closed, I visited England and France,
for the double purpose of submitting my invention to the
test of European criticism, and to secure to myself some
remuneration for my large expenditures of time and money in
elaborating my invention. In France, after a patent had been
secured in that country, my telegraph first attracted the
attention of the Academy of Sciences, and its operation was
shown, and its principles were explained, by the celebrated
philosopher, Arago, in the session of that distinguished
body of learned men, on September 10, 1838. Its reception
was of the most enthusiastic character. Several other
societies, among which were the Academy of Industry and the
Philotechnic Society, appointed committees to examine and
report upon the invention, from all which I received votes
of thanks, and from the former the large medal of honour.
The French Government at this time had its attention drawn
to the subject of electric telegraphs, several systems
having been presented for its consideration, from England,
Germany and France. Through the kind offices of our minister
at the French Court, General Cass, my telegraph was also
submitted; and the Minister of the Interior (M. Montalivet)
appointed a commission, at the head of which was placed M.
Alphonse Foy, the administrator-in-chief of the telegraphs
of France, with directions to examine and report upon all
the various systems which had been presented. The result
of this examination (in which the ingenious systems of
Professor Wheatstone, of London, of Professor Steinheil, of
Munich, and Professor Masson, of Caen, passed in review)
was a report to the Minister in favor of mine. In a note
addressed to me by M. Foy, who had expressed his warmest
admiration of my telegraph in my presence, he thus writes:
“I take a true pleasure in confirming to you in writing
that which I have already had the honor to say to you
viva voce, that I have prominently presented (signalé) to
Monsieur the Minister of the Interior your electro magnetic
telegraph, as being the system which presents the best
chance of a practical application; and I have stated to him
that if some trials are to be made with electric telegraphs,
I hesitate not to recommend that they should be made with
your apparatus.”
In England, my application for a patent for my invention
was opposed before the Attorney General by Professor
Wheatstone and Mr. Davy, each of whom had systems already
patented, essentially like each other, but very different
from mine. A patent was denied me by the Attorney General,
Sir John Campbell, on a plea which I am confident will
not bear a legal examination. But there being no appeal
from the Attorney General’s decision, nor remedy, except
at enormous expense, I am deprived of all benefit from my
invention in England. Other causes than impartial justice
evidently operated against me. An interest for my invention,
however, sprung up voluntarily, and quite unexpectedly,
among the English nobility and gentry in Paris, and, had
I possessed the requisite funds to prosecute my rights
before the British Parliament, I could scarcely have failed
to secure them, so powerfully was I supported by this
interest in my favour; and I should be ungrateful did I not
take every opportunity to acknowledge the kindness of the
several noblemen and gentlemen who volunteered to aid me in
obtaining my rights in England, among the foremost of whom
were the Earl of Lincoln, the late celebrated Earl of Elgin,
and the Hon. Henry Drummond.
I returned to the United States in the spring of 1839,
under an engagement entered into in Paris with the Russian
Counsellor of State, the Baron Alexandre de Meyendorff, to
visit St. Petersburg with a distinguished French savant, M.
Amyot, for the purpose of establishing my telegraphic system
in that country. The contract, formally entered into, was
transmitted to St. Petersburg, for the signature of the
Emperor, which I was led to believe would be given without a
doubt; and, that no time should be lost in my preparations,
the contract, duly signed, was to be transmitted to me in
in New York, through the Russian ambassador in the United
States, in four or five weeks, at farthest, after my arrival
home.
After waiting, in anxious suspense, for as many months,
without any intelligence, I learned _indirectly_ that the
Emperor, from causes not satisfactorily explained, refused
to sign the contract.
These disappointments, (not at all affecting the
scientific or practical character of my invention,) combined
with the financial depression of the country, compelled me
to rest a while from further prosecuting my enterprise.
For the last two years, however, under many discouraging
circumstances, from want of the requisite funds for more
thoroughly investigating some of the principles involved in
the invention, I have, nevertheless, been able to resolve
all the doubts that lingered in my own mind, in regard to
the perfect practicability of establishing my telegraphic
system to any extent on the globe. I say, “doubts that
lingered in my own mind;” the principle, and, indeed, the
only one of a scientific character, which at all troubled
me, I will state, and the manner in which it has been
resolved:
At an early stage of my experiments, I found that the
magnetic power produced in an electro magnet, by a single
galvanic pair, diminished rapidly as the length of the
conductors increased. Ordinary reasoning on this fact would
lead to a conclusion fatal to the whole invention, since
at a great distance I could not operate at all, or, in order
to operate, I should be compelled to make use of a battery
of such a size as would render the whole plan in effect
impracticable. I was, indeed, aware, that by multiplying
the pairs in the battery—that is, increasing the intensity
of its propulsive power, certain effects could be produced
at great distances, such as the decomposition of water, a
visible spark, and the deflection of the magnetic needle.
But as magnetic effects, except in the latter case, had not,
to my knowledge been made the subject of careful experiment,
and as these various effects of electrical action seemed,
in some respects, to be obedient to different laws, I did
not feel entirely assured that magnetism could be produced
by a multiplication of pairs sufficiently powerful at a
great distance to effect my purpose. From a series of
experiments which I made, in conjunction with Professor
Fisher, during the last summer, upon 33 miles of wire, the
interesting fact so favorable to my telegraphic system,
was fully verified, that _while the distance increased
in an arithmetical ratio, an addition to the series of
galvanic pairs of plates increased the magnetic power in
a geometric ratio_. Fifty pairs of plates were used as a
constant power. Two miles of conductors at a time, from two
to thirty-three, were successively added to the distance.
The weight upheld by the magnet from the magnetism produced
by 50 pairs, gradually diminished up to the distance of 10
miles; after which, _the addition of miles of wire up to 33
miles_ (the extent to which we were able to try it) _caused
no further visible diminution of power_. The weight then
sustained was a constant quantity. The practical deduction
from these experiments is the fact that with a very small
battery all the effects I desire, and at any distance, can
be produced. In the experiments alluded to, the fifty pairs
did not occupy a space of more than 8 cubic inches, and they
comprised but 50 square inches of active surface.
The practicability of establishing my telegraphic system
is thus relieved from all scientific objections.
Let me now turn your attention, sir, one moment to a
consideration of the telegraph as a source of revenue. The
imperfections of the common systems, particularly their
uselessness, on account of the weather, three quarters of
the time, have concealed from view so natural a fruit of a
perfected telegraphic system. So uncertain are the common
telegraphs as to time, and so meager in the quantity of
intelligence they can transmit under the most favorable
circumstances, that the idea of making them a source of
revenue would not be likely to occur. So far, indeed, from
being a source of revenue, the systems in common use in
Europe are sustained at great expense; an expense which,
imperfect as they are, is justified, in the view of the
Government, by the great political advantages which they
produce. Telegraphs with them are a Government monopoly,
and used only for Government purposes. They are in harmony
with the genius of those Governments. The people have no
advantage from them, except indirectly as the Government
is benefitted. Were our mails used solely for the purpose
of the Government, and private individuals forbidden to
correspond by them, they would furnish a good illustration
of the operation of the common European telegraphic systems.
The electro magnetic telegraph, I would fain think, is
more in consonance with the political institutions under
which we live, and is fitted, like the mail system, to
diffuse its benefits alike to the Government and to the
people at large.
As a source of _revenue_, then, to the Government, few,
I believe, have seriously computed the great profits to be
derived from such a system of telegraphs as I propose; and
yet there are sure data already obtained by which they can
be demonstrated.
The first fact is, that every minute of the 24 hours is
available to send intelligence.
The second fact is, that 12 signs, at least, can be sent
in a minute, instantaneously, as any one may have proof
by actual demonstration of the fact on the instrument now
operating in the capitol.[15]
[15] 98, per minute, can now be sent, 1845.
There can be no doubt that the cases, where such speedy
transmission of intelligence from one distant city to
another is desirable, are so numerous, that when once the
line is made for such transmission, it will be in constant
use, and a demand made for a greater number of lines.
The paramount convenience, to commercial agents and
others, of thus corresponding at a distance, will authorize
_a rate of postage proportionate to the distance_, on the
principle of rating postage by the mails.
To illustrate the operation of the telegraph in increasing
the revenue, let us suppose that but 18 hours of the 24 are
efficiently used for the actual purposes of revenue; that
6 hours are allowed for repetitions and other purposes,
which is a large allowance. This would give, upon a single
circuit, 12,960 signs per day, upon which a rate of postage
is to be charged. Intelligence of great extent may be
comprised in a few signs. Suppose the following commercial
communication is to be transmitted from New York to New
Orleans:
Yrs., Dec. 21, rec. Buy 25 bales c., at 9, and 300 pork, at 8.
Here are 36 signs, which take three minutes in the
transmission from New York to New Orleans, and which informs
the New York merchant’s correspondent at New Orleans of
the receipt of a certain document, and gives him orders to
purchase 25 bales of cotton at 9 cents per pound, and 300
barrels of pork at 8 cents per pound. Thus may be completed,
in three minutes, a transaction in business which now would
take at least four or five weeks to accomplish.
Suppose that one cent per sign be charged for the first
100 miles, increasing the charge at the rate of half a
cent each additional 100 miles, the postage of the above
communication would be $2.88 for a distance of 1,500
miles. It would be sent 100 miles for 36 cents. Would any
merchant grudge so small a sum for sending such an amount of
information in so short a time to such a distance? If time
is money, and to save time is to save money, surely such an
immense saving of time is the saving of an immense sum of
money. A telegraphic line of a single circuit only, from New
York to New Orleans, would realize, then, to the Government,
_daily_, in the correspondence between those two cities
alone, over _one thousand dollars_ gross receipts, or over
$300,000 per annum.
But it is a well-established fact, that, as facilities of
intercourse increase between different parts of the country,
the greater is that intercourse. Thousands travel, in this
day of rail roads and steamboats, who never thought of
leaving their homes before. Establish, then, the means of
instantaneous communication between the most distant places,
and the telegraphic line of a single circuit will very soon
be insufficient to supply the demands of the public—they
will require more.
Two circuits will of course _double the facilities, and
double the revenue_; but it is an important fact, that the
expense of afterwards establishing a second, or any number
of circuits, does not proceed on the _doubling_ principle.
If a channel for conveying a single circuit be made, in the
first instance, of sufficient capacity to contain many more
circuits, which can easily be done, additional circuits can
be laid as fast as they are called for, at but little more
than the cost of the prepared wire. The recent discovery
of Professor Fisher and myself, shows that a single wire
may be made the common conductor for at least six circuits.
How many more we have not yet ascertained. So that, to add
another circuit is but to add another wire. Fifty dollars
per mile under these circumstances, would therefore add the
means of doubling the facilities and the revenue.
Between New York and Philadelphia, for example, the whole
cost of laying such an additional circuit would be but
$5,000, which would be more than defrayed by _two months’_
receipts only from the telegraphs between those two cities.
There are two modes of establishing the line of conductors.
The first and cheapest is doubtless that of erecting spars
about 30 feet in height and 350 feet apart, extending the
conductors along the tops of the spars. This method has some
obvious disadvantages. The expense would be from $350 to 400
per mile.
The second method is that of enclosing the conductors in
leaden tubes, and laying them in the earth. I have made the
following estimate of the cost of this method:
Wire, prepared, per mile, $ 150.00
Lead pipe, with solderings, 250.00
Delivery of the pipe and wire, 25.00
Passing wire into the pipes, 5.00
Excavations and filling in about 1,000 yards per mile,
or 3 feet deep, at 15 cents per square yard, 150.00
Laying down the pipe, 3.00
——————
583.00
======
One register, with its machinery, comprising a galvanic
battery of four pairs of my double-cup battery, $ 100.00
One battery of 200 pairs, 100.00
======
Expense for thirty nine miles, $ 22,837.00
Two registers, 200.00
Two batteries, 200.00
Services of chief superintendent of construction,
per annum, 2,000.00
Services of three assistants, at $1,500 each,
per annum, 4,500.00
————————
$ 29,637.00
==========
As experience alone can determine the best mode of
securing the conductors, I should wish the means and
opportunity of trying various modes, to such an extent as
will demonstrate the best.
Before closing my letter, sir, I ought to give you the
proofs I possess that the American telegraph has the
_priority in the time of its invention_.
The two European telegraphs in practical operation are
Professor Steinheil’s of Munich, and Professor Wheatstone’s
of London. The former is adopted by the Bavarian Government;
the latter is established about 200 miles in England,
under the direction of a company in London. In a highly
interesting paper on the subject of telegraphs, translated
and inserted in the London Annals of Electricity, March and
April, 1839, Professor Steinheil gives a brief sketch of
all the various projects of electric telegraphs, from the
time of Franklin’s electrical experiments to the present
day. Until the birth of the science of electro magnetism,
generated by the important discovery of Oersted, in 1820,
of the action of electric currents upon the magnetic
needle, the electric telegraph was but a philosophic toy,
complicated and practically useless. Let it be here
noticed, that, after this discovery of Oersted, the
_deflection of the needle_ became the principle upon which
the savants of Europe based all their attempts to construct
an electric telegraph. The celebrated Ampère, in the same
year of Oersted’s discovery, suggested a plan of telegraphs,
to consist of a magnetic needle, and a circuit for each
letter of the alphabet and the numerals—making it necessary
to have some 60 or 70 wires between the two termini of the
telegraphic line.
This suggestion of Ampère is doubtless the parent of all
the attempts in Europe, both abortive and successful, for
constructing an electric telegraph.
Under this head may be arranged the Baron Schilling’s
at St. Petersburg, consisting of 36 magnetic needles, and
upwards of 60 metallic conductors, and invented, it seems,
at the same date with my electro magnetic telegraph, in the
autumn of 1832. Under the same head comes that of professors
Gauss and Weber, of Göttingen, in 1833, who simplified the
plan by using but a single needle and a single circuit.
Professor Wheatstone’s of London, invented in 1837, comes
under the same category; he employs five needles and six
conductors. Professor Steinheil’s, also invented in 1837,
employs two needles and two conductors.
But there was another discovery, in the infancy of
the science of electro magnetism, by Ampère and Arago,
immediately consequent on that of Oersted, namely: the
_electro magnet_, which none of the savants of Europe who
have planned electric telegraphs ever thought of applying,
until within two years past, for the purpose of signals. My
telegraph is essentially based on this latter discovery.
Supposing my telegraph to be based on the same principle
with the European electric telegraphs, which it is not,
mine, having been invented in 1832, would still have the
precedence, by some months at least, of Gauss and Weber’s,
to whom Steinheil gives the credit of being the first to
simplify and make practicable the electric telegraph. But
when it is considered that all the European telegraphs make
use of the deflection of the needle to accomplish their
results, and that none use the _attractive power of the
electro magnet to write in legible characters_, I think I
can claim, without injustice to others, to be the first
inventor of the _electro magnet telegraph_.
In 1839, I visited London, on my return from France, and
through the polite solicitations of the Earl of Lincoln,
showed and explained its operation at his house, on the 19th
of March, 1839, to a large company which he had expressly
invited for the purpose, composed of Lords of the Admiralty,
members of the Royal Society, and members of both Houses of
Parliament.
Professor Wheatstone has announced that he has recently
(in 1840) also invented and patented an _electro magnetic
telegraph_, differing altogether from his invention of 1837,
which he calls his _magnetic needle telegraph_. His is,
therefore, the first European electro magnetic telegraph,
and was invented, as is perceived, eight years subsequent to
mine, and one year after my telegraph _was exhibited in the
public manner described at the Earl of Lincoln’s residence
in London_.
I am the more minute in adducing this evidence of
priority of invention to you, sir, since I have frequently
been charged by Europeans, in my own country, with merely
imitating long known European inventions. It is, therefore
due to my own country, as well as to myself, that in this
matter the facts should be known.
Professor Steinheil’s telegraph is the only European
telegraph that professes to _write_ the intelligence. He
records, however, by the delicate touch of the needle in its
deflections, with what practical effect I am unable to say;
but I should think that it was too delicate and uncertain,
especially as compared with the strong and efficient power
which may be produced in any degree by the electro magnet.
I have devoted many years of my life to this invention,
sustained in many disappointments by the belief that it
is destined eventually to confer immense benefits upon my
country and the world.
I am persuaded that whatever facilitates intercourse
between the different portions of the human family will
have the effect, under guidance of sound moral principles,
to promote the best interests of man. I ask of Congress the
means of demonstrating its efficiency.
I remain, sir, with great respect, your most obedient
servant,
SAM. F. B. MORSE.
Hon. CHARLES G. FERRIS,
_Member of the House of Representatives from the city of
New York and one of the Committee on Commerce, to whom
was referred the subject of the expediency of adopting
a system of electro magnetic telegraphs for the United
States._
No. 14.
_Communication from the Secretary of the Treasury,
transmitting the Report of Professor Morse, announcing
the completion of the Electro Magnetic Telegraph between
the cities of Washington and Baltimore. June 6, 1844.
Referred to the Committee on Commerce._
TREASURY DEPARTMENT, _June 4, 1844_.
SIR: I have the honour respectfully to transmit
herewith, for information of the House of Representatives,
a report, dated the 3d instant, from Professor Sam. F. B.
Morse, announcing the completion of the electro magnetic
telegraph between Washington and the city of Baltimore,
as authorized by the “Act to test the practicability of
establishing a system of electro magnetic telegraphs by the
United States,” approved the 3d of March, 1843.
I beg leave to state, that the perfect practicability of
the system has been fully and satisfactorily established by
the work already completed.
The subject is respectfully submitted to the consideration
of Congress for such further directions in the matter as may
be deemed expedient.
I have the honor to be, very respectfully, your obedient
servant,
McCLINTOCK YOUNG,
_Secretary of the Treasury ad interim._
Hon. JOHN W. JONES,
_Speaker of the House of Representatives._
No. 15.
_Letter from Professor Morse to Hon. McClintock Young._
WASHINGTON, _June 3, 1844_.
SIR: I have the honour to report that the
experimental essay authorized by the act of Congress on
March 3d, 1843, appropriating $30,000 for “testing” my
“system of electro magnetic telegraphs, and of such length,
and between such points, as shall test its _practicability_
and _utility_,” has been made between Washington and
Baltimore—a distance of forty miles—connecting the capitol
in the former city, with the rail road depot in Pratt
street, in the latter city.
On the first point proposed to be settled by the
experiment—to wit, its _practicability_—it is scarcely
necessary to say (since the public demonstration which has
been given of its efficacy, for some days past, during
the session of the different conventions in the city of
Baltimore) that it is fully proved.
Items of intelligence of all kinds have been transmitted
back and forth, from the simple sending of names, to the
more lengthened details of the proceedings of Congress and
the conventions. One fact will, perhaps, be sufficient to
illustrate the efficiency and speed with which intelligence
can be communicated by the telegraph.
In the proceedings of the democratic convention at
Baltimore for the nomination of a candidate for President
of the United States at the next election, the result of
the votes in the nomination of the Hon. J. K. Polk was
conveyed from the convention to the telegraphic terminus
in Baltimore, transmitted to Washington, announced to the
hundreds assembled in front of the terminus at the Capitol,
and to both Houses of Congress; the reception of the news at
Washington was then transmitted to Baltimore, sent to the
convention and circulated among its members—all before
the nomination of the successful candidate was _officially
announced_ by the presiding officer of the convention.
In regard to the _utility_ of the telegraph, time alone
can determine and develop the whole capacity for good of so
perfect a system. In the few days of its infancy, it has
already casually shown its usefulness in the relief, in
various ways, of the anxieties of thousands; and, when such
a sure means of relief is available to the public at large,
the amount of its usefulness becomes incalculable.
An instance or two will best illustrate this quality of
the telegraph:
A family in Washington was thrown into great distress
by a rumor that one of its members had met with a violent
death in Baltimore the evening before. Several hours must
have elapsed ere their state of suspense could be relieved
by the ordinary means of conveyance. A note was despatched
to the telegraph rooms at the Capitol, requesting to have
inquiry made at Baltimore. The messenger had occasion to
wait but _ten minutes_, when the proper inquiry was made
at Baltimore, and the answer returned that the rumor was
without foundation. Thus was a worthy family relieved
immediately from a state of distressing suspense.
An inquiry from a person in Baltimore holding the check
of a gentleman in Washington, upon the Bank of Washington,
was sent by telegraph, to ascertain if the gentleman in
question had funds in that bank. A messenger was instantly
despatched from the Capitol, who returned in a few minutes
with an affirmative answer, which was returned to Baltimore
instantly; thus establishing a confidence in a money
arrangement, which might have affected unfavorably (for many
hours at least) the business transactions of a man in good
credit.
Other cases might be given; but these are deemed
sufficient to illustrate the point of utility, and to
suggest to those who will reflect upon them, thousands of
cases in the public business, in commercial operations, and
in private and social transactions, which establish beyond
a doubt the immense advantages of such a speedy mode of
conveying intelligence.
In the construction of this _first line of conductors_, it
was necessary that experiments should be made to ascertain
the best mode of establishing them. The plan I first
suggested in my letter to the Secretary of the Treasury
in 1837, (see the House report, No. 6, April 6, 1838,) of
placing my conductors upon posts thirty feet high, and some
three hundred feet apart, is, after experiment, proved to be
the most eligible. The objection, so strongly urged in the
outset, that, by being exposed above ground, the conductors
were in danger from evil disposed persons, had such weight
with me, in the absence of experience on the subject, as
early to turn my whole attention to the practicability of
placing my conductors in tubes beneath the earth, as the
best means of safety. The adoption of this latter mode, for
some thirteen miles in England, by the projectors of the
English telegraph, confirmed me in the belief that this
would be best. I was thus led to contract for lead pipe
sufficient to contain my conductors through the whole route.
Experience, however, has shown that this mode is attended
with disadvantages far outweighing any advantages from its
fancied security beneath the ground. If apparently more
secure, an injury once sustained is much more difficult
of access, and of repair; while upon posts, if injury
is sustained, it is at once seen, and can be repaired,
ordinarily almost without cost. But the great advantage
of the mode on posts over that beneath the ground, is the
cheapness of its construction. This will be manifest from
the following comparative estimate of the two modes in
England and in America:
_Cost of English Telegraph._
In pipe, _£_287 6_s._, or $1,275 per mile.
On posts, _£_149 5_s._, or $662 per mile.
_Cost of American Telegraph,
as estimated in House Report, No. 17,
27th Congress, 3d session._
In pipe, $583 per mile.
On posts, from $350 to $400 per mile.
These comparisons also show how much less is the cost
of the American telegraph, even at the highest estimate.
But these estimates of the cost of construction,
largely exceed the actual cost, under the improved modes
recently suggested by experiment, and now adopted; and
the cost of the line between Baltimore and Washington,
already constructed, involves numerous expenditures of an
experimental character, which will not be incident to an
extension of the line onward to New York, if that shall be
deemed desirable.
Of the appropriation made, there will remain in the
treasury, after the settlement of outstanding accounts,
about $3,500, which may be needed for contingent
liabilities, and for sustaining the line already
constructed, until provision by law shall be made for such
an organization of a telegraphic department or bureau as
shall enable the telegraph at least to support itself,
if not to become a profitable source of revenue to the
Government.
I will conclude by saying, that I feel grateful for the
generous confidence which Congress has thus far extended
toward me and my enterprise; and I will cheerfully afford
any further and more detailed information on the subject of
the telegraph, when desired, and will be prepared to make
and execute any desirable arrangements for the extension of
it that Congress shall require.
With great respect, your obedient servant,
SAM. F. B. MORSE,
_Superintendent of Electro Magnetic Telegraph._
To the Hon. McCLINTOCK YOUNG,
_Secretary of the Treasury ad interim_.
No. 16.
_Letter from the Secretary of the Treasury,
transmitting a letter from Professor Morse,
relative to the Magnetic Telegraph,
Dec’r 23, 1844._
TREASURY DEPARTMENT, _December 17, 1844_.
SIR: In compliance with the request made in your
letter of this date, in behalf of the Committee on Commerce
of the House of Representatives, for information from this
department upon the subject of “Morse’s telegraph,” I have
the honour respectfully to transmit herewith a communication
from Professor Morse, dated the 12th instant, containing
specific information in regard to that work.
I have the honour to be, very respectfully, your obedient servant,
GEO. M. BIBB,
_Secretary of the Treasury._
Hon. ISAAC E. HOLMES,
_Chairman of Committee on Commerce,
House of Representatives_.
No. 17.
_Letter from Prof. Morse to the Hon. G. M. Bibb._
WASHINGTON, _December 12, 1844_.
SIR: I have the honour respectfully to submit
some facts in relation to the electro magnetic telegraph,
bearing upon the bill now before Congress, reported from the
Committee on Commerce of the House, for the extension of the
telegraphic line from Baltimore to New York.
By a reference to documents in the records of the government,
it will appear, that the subject of establishing a system
of telegraphs for the use of the United States has been,
occasionally, for many years, before Congress; but nothing
effective was ever done in relation to the matter, until
the Hon. Levi Woodbury, while Secretary of the Treasury,
by addressing circular letters to various individuals in
the United States, (among which was one to me,) drew forth
from me a general description of the advantages of a system
of electro magnetic telegraphs which I had invented in
1832, on my passage from France to the United States. For
my answer to this circular letter, see No. 2, taken from
House report, No. 753, 25th Congress, second session; and I
refer to it now, to show that the assertions respecting the
practicability and utility of my system have been fully and
satisfactorily sustained by the result of the experimental
essay, authorized by the government, establishing the line
between Washington and Baltimore.
That which seemed to many chimerical at the time, is now
completely realized. The most sceptical are convinced;
and the daily and hourly operations of the telegraph in
transmitting information of any kind are so publicly known,
and the public feeling in regard to it so universally
expressed, that I need here only give a few instances of its
action, further to illustrate its character.
The facts in relation to the transmission of the
proceedings of the democratic convention of Baltimore, in
May last are well known, and are alluded to in my report to
the department, June 3d, 1844, No. 15. Since the adjournment
of Congress in June last, and during the summer and the
autumn, the telegraph has been in constant readiness for
operation, and there has been time to test many points in
relation to it, which needed experience to settle.
For more now than _eight months_, the conductors for the
telegraph, carried on elevated posts for 40 miles, have
remained undisturbed from the wantonness or evil disposition
of any one. Not a single instance of the kind has occurred.
In several instances, indeed, the communication has been
interrupted by accidents, but then only for a very brief
period. One of these was by the great fire in Pratt
street, Baltimore, which destroyed one of the posts, and
consequently, temporarily stopped the communication; but
in two or three hours the damage was repaired, and the
first notice of the accident and all the particulars were
transmitted to Washington by the telegraph itself.
Another instance of interruption was occasioned by the
falling of a tree, which accidently fell across the wires,
and at the same time across the rail road track, stopping
the cars for a short time, and the telegraphic communication
for two hours.
Excepting the time excluded by these, and two or three
other similar accidental interruptions, and which, during
seven months of its effective existence between the two
cities, does not altogether amount to more than 24 hours,
the telegraph has been either in operation, or prepared
for operation, at any hour of the day or night, irrespective
of the state of the weather.
It has transmitted intelligence of great importance.
During the troubles in Philadelphia the last summer,
sealed despatches were sent by express from the Mayor of
Philadelphia to the President of the United States. On the
arrival of the express at Baltimore, the purport of the
despatches transpired; and while the express train was in
preparation for Washington, the intelligence was sent to
Washington by telegraph, accompanied by an order from the
president of the rail road company to prevent the Washington
burden train from leaving until the express should arrive.
The order was given and complied with. The express had a
clear track, and the President and the Cabinet (being in
council) had notice both of the fact that an express was
on its way with important despatches to them, and also of
the nature of those despatches, so that, when the express
arrived, the answer was in readiness for the messenger.
In October, a deserter from the U.S. ship Pennsylvania,
lying at Norfolk, who had defrauded also the purser of
the ship of some $600 or $700, was supposed to have gone
to Baltimore. The purser called at the telegraph office
in Washington, stated his case, and wished to give notice
in Baltimore, at the same time offering a reward for the
apprehension of the culprit. The name and description of
the offender’s person, with the offer of the reward, were
sent to Baltimore, and in ten minutes the warrant was in the
hands of the officers of justice for his arrest; and in half
an hour from the time that the purser profferred his request
at Washington, it was announced from Baltimore by the
telegraph, “The deserter is arrested; he is in jail; what
shall be done with him?”
To show the variety of the operations of the telegraph,
a game of draughts, and several games of chess, have been
played between the cities of Baltimore and Washington, with
the same ease as if the players were seated at the same
table. To illustrate the independence of the telegraph of
the weather, and time of day, I would state that, during
the severe storm of the 5th December, when the night was
intensely dark, the rain descending in torrents, and
the wind blowing a gale, it seemed more than ordinarily
mysterious to see a company around a table, in a warm
retired chamber, on such a night, in Washington, playing a
game of chess with another company similarly situated in
Baltimore: the darkness, the rain, and the wind, being no
impediment to instantaneous communication.
In regard to the quantity of intelligence which may be
sent in a given time, it is perfectly safe to say that
thirty characters can be transmitted in a minute by a single
instrument; and as these characters are conventional signs,
they may mean either _numbers_, _letters_, _words_, or
_sentences_. As an illustration of this point, I will
state that nearly a whole column (more than seven-eighths)
in the Baltimore Patriot was transmitted in thirty
minutes—faster than the reporter in Baltimore could
transcribe.
This fact bears upon the ability of producing a revenue
from the telegraph; and I would suggest the propriety of
permission being granted by Congress to the department,
to adjust a tariff of charges on intelligence sent by
telegraph, at such a rate of postage as shall at least
return to the treasury the interest of the capital expended
in the first construction, and after maintenance of the
telegraph.
In aid of this view of the subject, I beg to refer to
my letter to the chairman of the Committee on Commerce,
December 6, 1842, No. 13.
Since that was written, experience has shown that that
calculation is far below the real results. Instead of
_twelve signs_ in a minute, upon which that computation was
based, we must substitute _thirty_—a column of a newspaper
having been transmitted to Baltimore even at the rate of
_thirty-five_ signs in a minute. It is, therefore, safe to
set down the rate at 30 signs per minute; and it is safe to
double the annual receipts, making the gross amount $600,000
per annum.
In the absence of experience, the expense necessary to
construct and to maintain a system of electro magnetic
telegraphs, was thought to be so great as to present a
formidable, if not an insurmountable obstacle to its
adoption. But the experiment already made for 40 miles,
has shown that the electro magnetic telegraph is far from
being expensive, either in its first construction, or after
maintenance, especially when its vast superiority over the
old system is taken into consideration.
To make this more clear, I give an abstract both of the
expenses and capacities of the ordinary visual telegraphs in
some of the European countries.
In England, the semaphore telegraph, established between
London and Portsmouth, a distance of 72 miles, is maintained
by the British government at an average expense of _£_3,405,
or $15,118 per annum. From a return [vol. 30, 1843, accounts
and papers of House of Commons] of the number of days
during which the telegraph was _not available_, on account
of the weather, during a period of three years, it appears
that there were, in that time, 323 days in which it was
useless, or nearly _one year out of three_! But by a return
made to the admiralty of the number of hours in the day
appointed for working the telegraph, it appears that the
hours appointed for the year are—from 1st October to 28th
February, from 10 o’clock, a. m., to 3 p. m.; 5 hours. From
1st March to 30th September, from 10 a. m., to 5 p. m.; 7
hours.
Average number of hours per day, in the most favourable
weather, 6 hours!
Deducting 1 year from the 3, for unavailable days, the
average time per day for the 3 years would be but 4 hours.
So that, for the use of their telegraph for 72 miles, and
for only 4 hours in the day, the British government expend
$15,118 per annum.
The French system of telegraphs is more extensive and
perfect than that of any other nation. It consists, at
present, of five great lines, extending from the capital to
the extreme cities of the kingdom, to wit:
The Calais line, from Paris to Calais, 152 miles
The Strasbourg line, from Paris to Strasbourg, 255 “
The Brest line, from Paris to Brest, 325 “
The Toulon line, from Paris to Toulon, 317 “
The Bayonne line, from Paris to Bayonne, 425 “
—————————
1,474 miles.
=============
Making a total of 1,474 miles of telegraphic intercourse.
These telegraphs are maintained by the French government at
an annual expense of over 1,000,000 of francs, or $202,000.
The whole extent, then, of the French lines of telegraph
is 1,474 miles, with 519 stations; and (if the estimate
for six stations, at an average cost of 4,400 francs, is a
criterion for the rest) erected at a cost of at least $880
each—making a total of $456,720.
The electro magnetic telegraph, at the rate proposed in
the bill, to wit, $461 per mile, (and which, it should be
remembered, will construct not _one_ line, only, but _six_,)
could be constructed the same distance for $619,514—not
one-third more than the cost of the French telegraphs. Even
supposing each line to be only as efficient as the French
telegraph, still there would be six times the facilities,
for not one-third more cost. But when it is considered that
the French telegraph, like the English, is unavailable the
greater part of the time, the advantages in favour of the
magnetic telegraph become more obvious.
An important difference between the two systems is, that
the foreign telegraphs are all a burden upon the treasury
of their respective countries; while the magnetic telegraph
proposes, and is alone capable of sustaining itself and of
producing a revenue.
Another difference in the two systems is, that the
stations in the foreign telegraphs must be within sight of
each other: a fact which bears essentially on the cost of
maintenance. The French telegraph requires for the distance
of 1,474 miles, no less than 519 stations—averaging _one
for about every three miles_. The number of stations of the
magnetic telegraph, on the contrary, is optional. The two
stations (one only at Baltimore, and one at Washington)
show that they may be at least 40 miles apart; and there
is no reason to doubt, from experiments I have made, that
100 miles, or even 500 miles, would give the same results.
In the maintenance, therefore, of stations, the magnetic
telegraph would require but 15 stations, (assuming that 100
miles is the _utmost limit_ of transmission between two
stations which is not probable;) while the French requires
519 for the same distance.
When to this are added the facts that the magnetic
telegraph is at _all times available_, at _every hour of the
day or night, irrespective of weather_; that, in comparison
with the visual telegraphs, it communicates _more than a
hundred-fold_ the quantity of intelligence in the same time;
that it is originally constructed at a _less cost_, (_all
things considered;_) that it is _maintained for less_; and
that it is capable, by a rate of charges for transmitting
intelligence, not only of defraying all its expenses, but,
if desired, of producing a revenue, I may be permitted to
hope that when these great advantages are fully understood,
my system will receive that attention from the government
which its intrinsic public importance demands.
I have as yet said nothing on the telegraph as a mighty
aid to national defence. Its importance in this respect
is so obvious, that I need not dilate. The importance
generally to the government and to the country, of a
_perfect_ telegraphic system, can scarcely be estimated by
the short distance already established between Baltimore and
Washington. But when all that transpires of public interest
at New Orleans, at St. Louis, at Pittsburgh, at Cincinnati,
at Buffalo, at Utica, at Albany, at Portland, at Portsmouth,
at Boston, at New York, at Philadelphia, at Baltimore, at
Washington, at Norfolk, at Richmond, at Charleston, at
Savannah, and at all desired intermediate points, shall
be _simultaneously_ known in each and all these places
together—when all the agents of the government, in every
part of the country, are in instantaneous communication
with head-quarters—when the several departments can at
once learn the actual existing condition of their remotest
agencies, and transmit at the moment their necessary orders
to meet any exigency—then will some estimates be formed
both of the powers and advantages of the magnetic telegraph.
Should the government be now disposed to possess the right
of the proprietors, by giving them a fair consideration, I
shall be ready to treat with them on the terms of transfer.
For myself, I should prefer that the government should
possess the invention, although the pecuniary interests of
the proprietors induce them to lean towards arrangements
with private companies.
In closing this report, I would take the opportunity
of favorably mentioning to the department the efficient
attention to the duties of their respective stations given
by my assistants, Alfred Vail and H. J. Rogers,
esqrs.—the former directing the correspondence at the
Washington terminus, and the latter at the Baltimore
terminus.
Very respectfully, sir, your obedient servant,
SAM. F. B. MORSE,
_Superintendent of Electro Magnetic Telegraphs
for the United States_.
To the Hon. GEO. M. BIBB,
_Secretary of the Treasury_.
_Magnetic Telegraph from Baltimore to New York, March 3, 1845._
Mr. CHAPPELL, from the Committee of Ways and Means,
made the following Report.
The Committee of Ways and Means, to whom was referred
a resolution instructing said committee to inquire
into the expediency of reporting a bill to continue
the Electro Magnetic Telegraph from Baltimore to New
York, by way of Philadelphia, beg leave to submit the
following report:
The authority given by the constitution to Congress
to establish post offices and post roads, so far as it
operates to confer on the government any power which would
not equally belong to it without that provision, amounts
simply to making the government, a public or a common
carrier of the written correspondence of individuals, and
of the lighter form of printed intelligence and news. In
other words, by virtue of this clause, the government is
authorized and required to pursue, on a scale commensurate
with the wants and extent of the country, the business of
receiving, transporting, and delivering letters, newspapers,
and pamphlets, for all persons, private, as well as public,
and to and from any and all places in the Union. And for
the service thus rendered, the government exacts from
the individuals served, a specific fee or compensation,
under the name of postage, for every letter or paper
transported and delivered. Now, it is quite obvious that
both the pursuit of this business, and the exaction of a
remuneration for it, would be altogether beyond the range of
federal authority, but for the specially granted power to
establish post offices and post roads. Mere silence in the
constitution on this subject would have effectually withheld
the power from the general government, and would have caused
the business of carrying letters, newspapers, &c., to remain
where all other branches of the carrying trade are actually
left—namely, in the hands of individual enterprise, subject
to State legislation, and to such (and no other) federal
control as is involved in the power of Congress to regulate
commerce among the States.
The functions thus devolved on the government, of
performing for the people the office of universal letter
carrier and news carrier, is a matter of the very highest
consequence in every light in which it can be viewed.
The bare fact that our ancestors refused to leave it
dependent on individual enterprise or State control, and
vested it expressly in Congress, abundantly attested their
anxious sense of its importance, and their conviction of
the impracticability of realizing the requisite public
advantages from it, otherwise than by giving it a federal
lodgment and administration.
Had not these advantages been regarded as attainable
in no other way, while, at the same time, they were felt
to be virtually necessary, the framers and adopters of
the constitution, devoted as they are known to have been
to the power and importance of the States, and jealously
apprehensive of the undue preponderance of the federal
branch, would never have consented to engraft on that branch
a power so great, so growing, so penetrating and pervading,
as that of the post office system—a power involving the
direct exercise of the carrying trade by the government
on a vast scale, and requiring, in order to its exercise,
the organization and maintenance of a huge and distinct
administrative department, which, in its operations, touches
daily and intimately the private affairs as well as public
interests of the people; receives and expends millions
of money every year; and continually employs, pays, and
controls many thousands of persons, scattered through all
parts of the country—thus adding mightily to federal power,
and especially to the influence and patronage of the federal
executive. These are all consequences which result directly
and necessarily from the bestowment of the post office power
on the general government. And inasmuch as the government
thus derives from that power so great an addition to its own
weight and influence, it certainly ought to be considered as
contracting therefrom a correspondently heavy obligation to
make the power advantageous and useful to the people, to the
utmost extent of which it is capable.
The government has ever shown itself fully sensible of
this obligation, and alive to its fulfilment. Hence, that
immense and minute machinery of post offices and post roads,
of postmasters, contractors, and carriers, which overspreads
the country, and meets us everywhere—all designed and kept
up for the sole purpose of bringing the contents of the
mail-bag, with frequency, regularity, and celerity, near to
the doors of our whole population. For many years, no better
or more expeditious means of conveyance could be found
than horse-power in the various forms in which it might be
applied on ordinary highways. But in those times, as well as
now, the government acted on the principle of not regarding
even a heavy increase of expense as an objection sufficient
to outweigh so important an object as the regular, frequent,
and rapid transmission of the mail between all the great points,
and along all the chief arteries of the country. On such
routes, accordingly, the mail was kept running without
interruption—by night as well as by day—and at the best
speed that could be secured by a well organized and costly
system of relays of men, horses, and vehicles.
But, at length, the ever advancing discoveries and
improvements of science and art threw into the shade, as
slow and inadequate, all the old and long used modes of
travel and transportation. Steamboats and railroads burst
upon the world, introducing a new and wonderful era in its
commerce and intercourse; private capital and enterprise
soon built them up, and put them in operation, whenever
a sufficiently tempting prospect of gain appeared; and
all private persons, as well as public departments, saw
presented to their option more perfect and expeditious
modes of transportation than could have possibly entered
into the anticipations of the framers of the constitution.
But, though not anticipated or foreseen, these new and
improved modes were as clearly within the purview of the
constitution, as were the older and less perfect ones with
which our ancestors were familiar. And there being no doubt
entertained either on this point, or as to the obligation
of the government to lay hold of the best and most rapid
methods of transmission which the improvements of the age
put in its reach, steam-power commended itself at once to
adoption, and has long been extensively employed, both on
land and water, for the carriage of the mail.
It is not without full reflection that the committee
insist on the principle that it was the duty as well as
the right of the government thus to avail itself, even at
heavy additional expense, of the powerful agency of steam,
for the purpose of accelerating the mails. It would have
been a gross and manifest dereliction to have permitted
that vitally important concern, the transportation of the
mail—a concern so anxiously intrusted by the constitution
to the federal authority—it would have been, in the opinion
of the committee, a gross and manifest dereliction to have
permitted it to lag behind the improvements of the age,
and to be outstripped by the pace of ordinary travel and
commercial communication. Such is the view which the Post
Office Department avowedly takes of its own obligations, and
upon which it habitually acts. To be outstripped by private
expresses, or by the ordinary lines of travel, is deemed
discreditable to the department, injurious to the general
interests of the country, and a thing, therefore, not to be
permitted.
This great and fundamental principle upon which the
departments acts, (of not being outstripped in the
transmission of correspondence and intelligence,) led
necessarily to subsidizing the steam-engine into the service
of the post office; and it must and will lead, with equal
certainty, to a like adoption of any other newly discovered
agency or contrivance possessing decided advantage of
celerity over previously used methods. It is not probable,
however, that the government will ever find itself called
upon to make any transition wider or more striking than that
already so familiar to us—a transition from the use of
animal power to the tremendous enginery of the steam-engine;
from common roads to iron railways; from land carriage to
the conversion of rivers, lakes, and the ocean itself, into
post roads.
The same principle which justified and demanded the
transference of the mail on many chief routes, from the
horse-drawn coach on common highways to steam-impelled
vehicles on land and water, is equally potent to warrant
the calling of the electro magnetic telegraph—that last
and most wondrous birth of this wonder-teeming age—in aid
of the post office, in discharge of its great function
of rapidly transmitting correspondence and intelligence.
And the only question to be considered, in determining
whether it ought to be so called in aid, is a question of
fact—namely, whether said telegraph possesses, over the
modes of transmission now in use by the department, any
advantages of sufficient value to justify the expense of
engraftment on the system.
Its first and most signal advantage consists in the truly
electrical celerity with which it transmits intelligence
and communications through the greatest distances. It
supplies, with a perfection like magic, the first and
most important and difficult _desideratum_ in a post
office establishment—especially in one which has to
serve a country so vast as ours. That desideratum is
despatch—rapidity of transmission. It is to secure this,
that the government pays a hugely greater price for the
carrying and delivery of the mails, than any other equal
_quantum_ of transportation costs in the world. Nature
seemed to have fixed certain limits to the speed of
transmission, which it seemed impossible to pass; and those
limits appeared to be reached by the steam-engine. But
they have been utterly transcended by the electro magnetic
telegraph, which has literally demolished time and space for
all purposes of correspondence between places connected by
its wonder-working wires.
Another inestimably important advantage of Professor
Morse’s telegraph consists in the fulness, precision, and
variety of matter which it is capable of communicating. Its
alphabet contains representatives of all the letters of our
language, and of all the numerals of arithmetic; and they
are capable of infinite combination and repetition under the
magnetic impulse. Hence it is obvious that the _capacity_ of
the instrument is competent to the communication of a long
discourse of the greatest variety of thought and expression.
But, as the telegraph letters must necessarily be despatched
along the wire, and marked down, one by one, at the station
to which they are transmitted, it is obvious that a long
discourse must occupy considerable time, although the
letters follow each other in the most rapid succession.
This brings the attention of the committee to a very
material point, namely: the quantum of matter, or amount
of intelligence, which the instrument would be capable
of transmitting in a given time. The ordinary average of
transmission is about thirty letters per minute along each
wire. Six wires can be erected at an expense of somewhat
less than $500 per mile, which would make the telegraph
competent to the transmission of one hundred and eighty
letters per minute, on an average. The words of our
language are estimated to average six letters to a word. A
telegraphic line composed of six wires, would, consequently,
be able to transmit per minute thirty words fully spelt.
But it is wholly unnecessary that the words should be fully
spelt by the instrument. By a well-contrived system of
abbreviations, the number of letters to be transmitted,
in order to communicate a given number of words, is
greatly diminished; and, of course, the number of words
transmissible in a given time is proportionably augmented.
To such great perfection has this system of conventional
abbreviations been carried, as to have enabled the
telegraph, on one occasion, to transmit in thirty minutes,
from Washington to Baltimore, congressional intelligence
enough to fill a column of the Baltimore Patriot. This
was done, too, with only one wire. Increase the number of
wires to six, as proposed in the bill introduced by the
Committee on Commerce, and it follows that the capacity of
the instrument will be adequate to the transmission of six
long newspaper columns of matter in half an hour. Then it
is to be further noted, that the telegraph is capable of
working throughout the whole twenty-four hours, without
intermission—in darkness as well as in daylight—in stormy
weather as well as in serene—which would enable it to
communicate in a single day two hundred and eighty-eight
long newspaper columns of matter. All these facts put
together, evince that the capacity of the instrument, in
reference not only to the celerity of its communications,
but in reference also to the kind and quantity of matter it
can communicate in a given time, is such as to recommend it
as a most efficient medium both of private correspondence
and public intelligence.
That it is capable of being, and will actually be, at no
distant day, extensively employed as such a medium, it seems
to the committee there can be but little room to doubt. Such
a result seems, indeed, to be rendered altogether certain,
when, in addition to the capacities of the instrument, we
take into consideration its cheapness. For little more than
$100,000, Baltimore can be connected with New York; and for
a like sum, New York with Boston. There would then be an
unbroken telegraphic line from Boston to Washington; passing
through New York, Philadelphia, Baltimore and the other
considerable towns on the route. What a vast number of short
commercial letters would such a line be able to attract to
itself, and to despatch every day, far in advance of
the ordinary transportation by mail. Nor would any danger
of a detrimental divulgence of their affairs exist to
deter merchants and men of business from resorting to the
telegraph; because, in the first place, the simple expedient
of a concerted cipher between distant correspondents would
protect their communications with a shield of secrecy
impenetrable even to the officers and managers of the
telegraph. And in the next place, the very nature of their
functions will require that these persons shall be men of
great trustworthiness, and that they shall moreover be
placed under the most stringent official obligations of
secrecy in regard to the contents of private communications.
Under such circumstances, men of business need no more
apprehend danger of improper publicity from employing the
telegraph, than from the necessity of having clerks in their
counting-houses to pen and copy their correspondence.
If all these advantages should have the effect of
attracting to the telegraph the amount of custom which to
the committee seems probable, it is obvious that a very
moderate tariff of charges would produce income enough to
make it a gainful property—at least upon such a line as
that from Boston to Washington. It is upon this ground the
committee base the belief that it is destined soon to be
established along that whole line, if not by government,
certainly by private capital and enterprise; and then a
state of things will immediately develop itself, which the
people will never endure nor tolerate the government in
permitting to exist. That state of things would be that the
post office, in its transportation of all correspondence and
news, would lag not hours, but days, behind the transmission
of the same things through another medium; and that, a
medium belonging to private individuals, and controlled by
private views and interests.
The importance of prompt action in the matter on the part
of the government is further apparent from the fact that the
invention is a private patented property. It is a property
to the production of which Professor Morse has devoted years
of the highest order of labour—the labour of genius and
science combined. Under the patronage and at the expense of
the government, he has been enabled to give to the world,
in the line between Baltimore and Washington, a visible
and perfectly triumphant demonstration of the success and
utility of his invention. But the pecuniary reward, to
which he is so justly entitled, remains yet in abeyance. It
depends upon his being successful in making contracts with
the government, or others, for the use of his invention.
And, of course, if government shall not speedily embrace the
project, and enable him to realize a compensation for his
discovery, he will be necessitated to look elsewhere for his
indemnification and reward. And, should the arrangements
into which he may find it necessary to enter with private
individuals or associations, stipulate exclusive rights in
their favour, it is manifest how greatly government
and people would lie at their mercy. Having in their
hands the monopoly of such a medium of intelligence on
the important lines, they could make such use of their
advantages over the government and the community as would
at length enable them to exact their own terms as the price
of the surrender of their exclusive right; for the truth
cannot be too often repeated, or too deeply impressed in
relation to the subject, that the people will never submit
long to the mischiefs and discredit of the public post
office transmission of correspondence and intelligence
being outstripped by any private monopoly or establishment
whatever. The loss of revenue will co-operate with the
complaints and sufferings of the people to compel the
government, in the long run, to do what were better done at
once—namely, to establish the telegraph in connection with,
and as a branch of, the post office, on such great lines
of communication as the correspondence and commerce of the
country may indicate.
An accident has occurred, during the present winter,
in the administration of the post office, to which the
committee beg leave to call the attention of the House,
as illustrative of the principles and policy by which the
Department avowedly feels itself bound, as the public organ
for the transmission of correspondence and intelligence. It
is well known that, from Boston to Covington, in Georgia,
the great southern and New Orleans mail is transported
wholly by steam-power, either on water or on rail roads.
It is carried this whole distance in five days. From
Covington to Mobile, it is carried in stages, with the
exception of a short interval of rail road in approaching
Montgomery, Alabama. At Mobile, the mail is again committed
to steam-carriage, by sea, to New Orleans. Now, of so much
importance was a single day’s anticipation of the mail
deemed in all the great cities on the route, that a private
express was established with that view, to be carried on
horseback between Covington and Montgomery. All matter
destined for the private express was addressed to the agents
of the company at Covington and Montgomery, according as
such matter should happen to come from the north or south.
The express carrier at Covington, receiving his despatches
from the northern mail on the arrival of the steam-cars,
delivered them at Montgomery to the post office again in
such time that they were sent from Montgomery to Mobile and
New Orleans by mail one day in advance of the other letters,
which reached Covington at the same time. The effect was,
the anticipation of the northern mail by one day at Mobile
and New Orleans; and the same operation, from Montgomery to
Covington, resulted in one day’s anticipation of the Mobile
and New Orleans mails at New York. What did the Post Office
Department do, under this state of facts? The answer to this
question is to be found on the records of the Department.
The Postmaster General, after watching these anticipations
for a short time, issued an order for their prevention by
the establishment of a post office express between Covington
and Montgomery, to run alongside the private express. In
the same manner, if the government shall not soon establish
the telegraph on public account on the great routes, it
will find the mails anticipated in the hundred-fold greater
degree by the establishment of private telegraphs, which
it will have to meet, either by purchasing them out on
exorbitant terms, or by erecting a rival public telegraph
line by their side.
The facts and reasonings which have now been submitted,
satisfy the committee that it is important that the
government should lose no time in occupying, with a
telegraph of its own, the ground between Baltimore and New
York. The committee look to the probability that the line
will afterwards he progressively extended northwardly,
southwardly, and westwardly, on routes the business
and correspondence on which shall justify and require
telegraphic facilities of communication.
Apart from the post office power, the government
undoubtedly possesses the authority to establish the
telegraph for its own use in the transmission of official
orders and communications. On this ground, as well as on
that growing out of the post office power, the committee
deem the constitutionality of the measure incontrovertible.
The committee might easily add to the views and arguments
which they have now presented, others of a highly commanding
character—especially those which relate to the extreme
value of which the magnetic telegraph would be in the
emergencies of war, and its singular adaptedness to render
our system of government easily and certainly maintainable
over the immense space from the Atlantic to the Pacific,
which our territory covers. Doubt has been entertained by
many patriotic minds how far the rapid, full, and thorough
intercommunication of thought and intelligence, so necessary
to a people living under a common representative republic,
could be expected to take place throughout such immense
bounds. That doubt can no longer exist. It has been resolved
and put an end to forever by the triumphant success of the
electro magnetic telegraph of Professor Morse, as already
tested by the government.
The fact that a bill has been long pending in the House,
introduced by the Committee on Commerce, for the extension
of the telegraph from Baltimore to New York, renders it
unnecessary for this committee to report a bill. Without
pronouncing positively on the sufficiency of the provisions
of that bill, the committee consider the whole subject
worthy the prompt attention of Congress.
Having thus presented their views on the subject referred
to them, the committee beg to be discharged from its further
consideration.
HISTORY OF TELEGRAPHS,
_Employing Electricity in Various Ways for the Transmission of
Intelligence._
We presume it will not be uninteresting to the reader, to be presented
with an account of the various discoveries, in their chronological
order, by which the science of Electricity became known to the world
during the seventeenth and eighteenth centuries, and _prepared the
way_ for those more magnificent results, which have been made in this
the nineteenth century. We will endeavour to make it as brief as is
consistent with the importance of the subject, to enable us to mark the
succession of discoveries and improvements through two hundred years.
More than any other branch of experimental philosophy, that of
electricity had been most neglected, until the seventeenth century. The
attractive power of amber is mentioned by Theophrastus and Pliny, and
also later by others.
[16]In the year 1600, William Gilbert, a native of Colchester, and a
London physician, published a Latin Treatise, _De Magnete_, in which
he relates a variety of electrical experiments. He increased the list
of electric bodies and also of substances upon which electrics could
act, and noted some of the circumstances relating to their action. His
theory of electricity was, however, very imperfect.
[16] Many of the facts here given, are taken from Priestley’s Work upon
Electricity.
In 1630, Nicolaus Cabœus at Terrara, repeated Gilbert’s experiments and
made some progress, increasing the list of electrics; as also did Mr.
Boyle in the year 1670. He made some discoveries which had escaped the
observation of those who preceded him. Cotemporary with Mr. Boyle, Otto
Guericke, burgomaster of Magdeburg, (the inventor of the air pump,)
made some advances. He constructed a sulphur globe, which he mounted
upon an axis, in a wooden frame, and causing it to revolve, at the same
time rubbing the globe with his hand, performed a variety of electrical
experiments. He was the first to discover, that a body once attracted
by an excited electric, was repelled by it, and not again attracted
until it had touched some other body. He observed the light and sound
produced by the electric fluid, while turning his electrical machine.
Dr. Wall about the same time observed the light and sound produced by
rubbing pieces of amber with wool, and also experienced a slight shock.
He compared the sound and light of the electric fluid so produced, to
thunder and lightning.
Sir Isaac Newton also engaged in similar electrical experiments, and
gave an account of them to the Royal Society in 1675. Mr. Hauksbee,
whose writings are dated 1709, distinguished himself by experiments
and discoveries in electrical attraction, and repulsion, and electric
light. He constructed an electrical machine, adopting the glass,
instead of the sulphur globe. He experimented upon the subtilty and
copiousness of the electric light, and likewise upon the sound and
shocks produced by the fluid. After the death of Mr. Hauksbee, the
science of electricity made but slow progress, and few experiments
were made for twenty years. In the year 1728, Mr. Stephen Grey, a
pensioner at the Charter House, commenced his experiments with an
excited glass tube. He and his friend, Mr. Wheeler, made a great
variety of experiments in which they demonstrated, that electricity
may be communicated from one body to another, even without being in
contact, and in this way, may be conducted to a great distance. Mr.
Grey afterwards found, that, by suspending rods of iron by silk or hair
lines, and bringing an excited tube under them, sparks might be drawn,
and a light perceived at the extremities in the dark. He electrified
a boy suspended by hair lines; and communicated electricity to a soap
bubble blown from a tobacco pipe. He electrified water, contained in a
dish, placed upon a cake of rosin, and also a tube of water. He made
some curious experiments upon a small cup of water, over which, at the
distance of an inch, he held the excited tube. He observed the water to
rise in a conical shape, from which proceeded a light; small particles
of water were thrown off from the cone, and the tube moistened.
Mr. Du Fay, intendant of the French king’s gardens, repeated the
experiments of Mr. Grey in 1733. He found that by wetting the
pack-thread he succeeded better with the experiment of communicating
the electric virtue through a line 1256 feet in length. He made the
discovery of two kinds of electricity, which he called _vitreous_ and
_resinous_; the former produced by rubbing glass, and the latter from
excited sulphur, sealing wax, &c. But this he afterwards gave up as
erroneous. Mr. Grey, in 1734, experimented upon iron rods and gave
rise to the term _metallic conductors_. He gave the name _pencil_ of
_electric light_ to the stream of electricity, such as is seen to issue
from an electric point. He suggested the idea that the electric virtue
of the excited tube was similar to that of thunder and lightning, and
that it could be accumulated.
Dr. Desaguliers commenced his experiments in 1739. He introduced the
term _conductor_ to that body to which the excited tube conveys its
electricity. He called bodies in which electricity may be excited
by rubbing or heating, _electric per se_; and _non-electric_ when
they receive electricity, and lose it at once upon the approach of
another non-electric. In the year 1742, several Germans engaged in
this subject. Mr. Boze, a professor at Wittemburg, revives the use of
Hauksbee’s globe, instead of using Grey’s glass tube, and added to it
a _prime conductor_. Mr. Winckler substituted a cushion instead of
the hand, which had before been employed to excite the globe. Mr. P.
Gordon, a Benedictine monk and professor of philosophy at Erford, was
the first who used a _cylinder_ instead of a globe. With his electrical
machine he conveyed the fluid through wires 200 ells in length and
killed small birds. Dr. Ludolf of Berlin, in the year 1744, kindled by
electricity the _ethereal spirit_ of Frobenius, by the excited glass
tube; the spark proceeding from an iron conductor. Mr. Boze fired
gunpowder by electricity. Mr. Gordon contrived the electrical star. Mr.
Winckler contrived a wheel to move by the agency of the same fluid.
Mr. Boze conveyed electricity from one man to another by a jet of
water, when both were placed upon cakes of rosin, six paces apart. Mr.
Gordon fired spirits, by a jet of water; and the Germans invented the
electrical bells.
Mr. Collinson in 1745 sent to the Library Company of Philadelphia, an
account of these experiments, together with a tube, and directions how
to use it. Franklin, with some of his friends, immediately engaged
in a course of experiments, the results of which are well known. He
was enabled to make a number of important discoveries, and to propose
theories to account for various phenomena, which have been universally
adopted, and which bid fair to endure for ages.
In the year 1745, such was the attention given to the subject of
electricity, that experiments upon it were publicly advertised and
exhibited for money in Germany and Holland. Dr. Miles, of England, in
the same year fired phosphorus by the application of the excited tube
itself without the intervention of a conductor. It was at this period
that Dr. Watson’s attention was given to this subject. He fired air,
made inflammable by a chemical process, and discharged a musket by
the electric fluid. He made many experiments, some of which will be
described as we proceed.
The year 1745 was made famous by the discovery of the _Leyden Phial_ by
Mr. Cuneus a native of Leyden. It appears also to have been discovered
by Mr. Von Kleist, dean of the Cathedral in Camin about the same time.
By this discovery, electricity could be accumulated and severe shocks
given. Mr. Gralath, in 1746, gave a shock to twenty persons at once,
and at a considerable distance from the machine. He constructed the
electrical battery by charging several phials at once. Mr. Winckler,
and also M. Monnier, in France, transmitted the electric fluid
through several feet of water as a part of the circuit. M. Nollet, in
France, killed birds and fishes by the discharge of the Leyden jars.
Improvements were made by Dr. Watson, and others, in the Leyden phial,
by coating the inside and outside of it with tin foil. Abbé Nollet
gave a shock to 180 of the guards in the king’s presence; and at the
grand convent of the Carthusians in Paris, the whole community formed a
line of 3600 feet in length, by means of wires between them. The whole
company upon the discharge of the phial, gave a sudden spring at the
same instant. The French philosophers tried the same experiment through
a circuit of persons, holding wires between them, two and a half
miles in length. In another experiment the water of the basin in the
Tuilleries was made a part of the circuit.
M. Monnier, the younger, to discover the velocity of electricity,
discharged the Leyden phial through an iron wire 4000 feet in length,
and another 1319 feet, but could not discover the time required for
its passage. Dr. Franklin communicated his observations, in a series
of letters, to his friend Collinson, the first of which is dated March
28, 1747. In these he shows the power of points in drawing and throwing
off the electrical matter. He also made the grand discovery of a _plus_
and _minus_, or of a _positive_ and _negative_ state of electricity.
Shortly after Franklin, from his principles of plus and minus state,
explained, in a satisfactory manner, the phenomena of the Leyden phial.
Dr. Watson and others in July 18, 1747, conveyed the electric fluid
across the Thames at Westminster bridge; the width of the river making
a part of the circuit. On the 24th of July, he tried the experiment
of forcing the electric fluid to make a circuit with the bend of the
river, at the New River at Stoke, Newington. He supposed that the
electric fluid would follow the river alone, through its circuitous
windings, and return by the wire. He suspected from the result of this
experiment, that the ground also conducted the fluid. On the 28th, he
proved the fact by supporting a wire 150 feet in length upon baked
sticks, using the ground as half of the circuit. On the 5th, of August,
he tried another experiment of making the _dry_ ground a part of the
circuit for a mile in extent, and found it to conduct equally as well
as water. The last experiment was tried at Shooter’s Hill, on the 14th
of August of the same year. But one shower of rain had fallen for the
five preceding weeks. The wires, two miles in length, were supported
upon baked sticks, and the dry ground was used for the return two miles
of the circuit. They found the transmission of the electric fluid to
be instantaneous. Dr. Watson made many other experiments which we must
pass over.
Mr. Ellicott constructed an electrometer for measuring the quantity of
electricity. Mr. Maimbury, at Edinburgh, electrified two myrtle trees,
during the month of October, 1746, when they put forth small branches
and blossoms sooner than other shrubs of the same kind, which had not
been electrified. The same experiment was tried upon seeds, sowed in
garden pots with the same success. Mr. Jallabert, Mr. Boze and the Abbé
Menon principal of the College of Bueil, at Angers, tried the same
experiments upon plants, by electrifying bottles in which they were
growing. He proved that electrified plants always grew faster, and had
finer stems, leaves and flowers than those which were not electrified.
In the year 1748, Dr. Franklin, and his friends, held an _electrical
feast_[17] on the banks of the Schuylkill near Philadelphia, and as the
account is amusing, as well as scientific, we will give an account of
it as related by Franklin, in a letter to his friend Collinson, dated
Philadelphia, 1748. (1 vol. of Franklin’s Works, p. 202.)
“Chagrined a little that we have been hitherto able to produce nothing
in this way of use to mankind; and the hot weather coming on, when
electrical experiments are not so agreeable, it is proposed to put
an end to them for this season, somewhat humorously, in a party of
pleasure, on the banks of the _Skuykil_.”
“Spirits, at the same time, are to be fired by a spark sent from side
to side through the river, without any other conductor than the water,
an experiment which we some time since performed, to the amazement
of many. A turkey is to be killed for our dinner by the _electrical
shock_, and roasted by the _electrical jack_, before a fire kindled
by the _electrified bottle_: when the healths of all the famous
electricians of England, Holland, France, and Germany are to be drank
in _electrified bumpers_,[18] under a discharge of guns from the
_electrical battery_.”
[17] “As the possibility of this experiment has not been easily
conceived, I shall here describe it. Two iron rods, about three feet
long, were planted just within the margin of the river, on the opposite
sides. A thick piece of wire, with a small round knob at its end,
was fixed on the top of one of the rods, bending downwards, so as to
deliver commodiously the spark upon the surface of the spirit. A small
wire, fastened by one end to the handle of the spoon containing the
spirit, was carried across the river, and supported in the air by the
rope commonly used to hold by, in drawing ferry boats over. The other
end of this wire was tied round the coating of the bottle; which being
charged, the spark was delivered from the hook to the top of the rod
standing in the water on that side. At the same instant the rod on
the other side delivered a spark into the spoon and fired the spirit;
the electric fire returning to the coating of the bottle, through the
handle of the spoon and the supported wire connected with them.”
[18] “An electrified bumper is a small thin glass tumbler, nearly
filled with wine, and electrified as the bottle. This, when brought to
the lips, gives a shock, if the party be close shaved, and does not
breathe on the liquor.”
“In the year 1749, Franklin first suggested his idea of explaining the
phenomena of thunder gusts, and of the aurora borealis, upon electrical
principles. He points out many particulars in which lightning and
electricity agree; in the same year he conceived the bold idea of
ascertaining the truth of his doctrine, by actually drawing down the
lightning, by means of sharp pointed iron rods, raised into the region
of the clouds. Admitting the identity of electricity and lightning,
and knowing the power of points in repelling bodies charged with
electricity, and in conducting the fluid silently and imperceptibly, he
suggested the idea of securing houses, ships, &c. from being damaged by
lightning, by raising pointed rods several feet above the most elevated
part of the building to be protected, and the other end descending some
feet into the ground. It was not until the summer of 1752, that he was
enabled to complete his grand discovery by experiments.”
“While he was waiting for the erection of a spire, it occurred to
him that he might have more ready access to the region of clouds, by
means of a common kite. He prepared one by fastening two cross sticks
to a silk handkerchief, which would not suffer so much from the rain
as paper. To the upright stick was affixed an iron point. The string
was, as usual, of hemp, except the lower end, which was silk. Where
the hempen string terminated, a key was fastened. With this apparatus,
on the appearance of a thunder gust approaching, he went out into the
commons, accompanied by his son, to whom alone he communicated his
intentions, well knowing the ridicule which, too generally for the
interests of science, awaits unsuccessful experiments in philosophy. He
placed himself under a shade, to avoid the rain; his kite was raised—a
thunder cloud passed over it—no sign of electricity appeared. He almost
despaired of success, when, suddenly, he observed the loose fibres of
his string to move towards an erect position. He now presented his
knuckle to the key, and received a strong spark; repeated sparks were
drawn from the key; a phial was charged, a shock given, and all the
experiments made which are usually performed with electricity.”
“Franklin constructed rods so as to bring the lightning into his house,
for the purpose of ascertaining if it was of the positive or negative
kind. He succeeded in the experiment for the first time in April, 1753,
when it appeared that the electricity was negative. On the 6th of June
he met with a cloud electrified positively. The discoveries of Franklin
roused the attention of all Europe, and many distinguished electricians
repeated them with success. Professor Richman, of St. Petersburg, while
making some experiments upon the electrical state of the atmosphere,
was killed by the electric fluid, August, 1753. Towards the end of the
eighteenth century, electricity was assiduously cultivated by a great
number of eminent individuals, who extended the boundaries of the
science by numerous experiments, and by the invention of ingenious and
useful instruments. Experiments were made upon air, water and ice; and
in relation to the surfaces of electric bodies; in relation to the two
electrical states; upon the deflagration of the metals; decomposition
of solids and liquids,” &c. &c.
_Lomond’s Electrical Telegraph._
It is stated in Young’s Travels in France, (1787, 4th ed. vol. 1, p.
79,) that a Mr. Lomond had invented a mode by which, from his own room,
he held communication with a person in a neighbouring chamber, by means
of electricity. He employed the common electrical machine placed at one
station, and at the other an electrometer constructed with pith balls.
These instruments were connected by means of two wires stretched from
one apartment to the other; so that, at each discharge of the Leyden
phial, the pith balls would recede from each other, until they came in
contact with the return wire. His system of telegraphic correspondence
is not related. We must suppose from the character of his invention,
having but one movement, that of the divergence of the balls, and using
an apparatus extremely delicate, that his means of communication could
not have been otherwise than limited, and required a great amount of
time.
The only mode in which it appears possible for him to have transmitted
intelligence, seems to be this: a single divergence of the pith balls,
succeeded by an interval of two or three seconds, may have represented
A. Two divergencies in quick succession, with an interval following,
may have represented B; three divergencies, in like manner, indicated
the letter C; and so on for the remainder of the alphabet. Instead of
these movements of the pith balls representing letters, they may have
indicated the numerals 1, 2, 3, &c. so that with a vocabulary of words,
numbered, conducted his correspondence. This appears to be the first
electrical telegraph of which we have any account; but does not appear
to have been used upon extended lines.
_Reizen’s Electric Spark Telegraph._
In 1794, according to Voigt’s Magazine, vol. 9, p. 1, Reizen made use
of the electric spark for telegraphic purposes. His plan was based upon
the phenomenon which is observed when the electric fluid of a common
machine is interrupted in its circuit by breaks in the wire, exhibiting
at the interrupted portions of the circuit a _bright spark_. The spark
thus rendered visible in its passage he appears to have employed in
this manner.
[Illustration: FIG. 34.]
Figure 34 is a representation of the table upon which were arranged
the letters of the alphabet, twenty-six in number. Each letter is
represented by strips of tin foil, passing from left to right, and
right to left, alternately, over a space of an inch square upon a
glass table. Such parts of the tin foil are cut out, as will represent
a particular letter. Thus, it will be seen that the letter A is
represented by those portions of the tin foil which have been taken
out, and the remaining portions answer as the conductor. P and N
represent the positive and negative ends of the strips, as they pass
through the table and reappear, one on each side of the small dot
at A. Those two lines which have a dot between, are the ends of the
negative and positive wire belonging to one of the letters. Now if a
spark from a charged receiver is sent through the wires belonging to
letter A, that letter will present a bright and luminous appearance
of the form of the letter A. “As the passage of the electric fluid
through a perfect conductor is unattended with light, and as the light
or spark appears only where imperfect conductors are thrown in its
way, hence the appearance of the light at those interrupted points of
the tin foil; the glass upon which the conductors are pasted, being
an imperfect conductor. The instant the discharge is made through the
wire, the spark is seen simultaneously at each of the interruptions, or
breaks, of the tin foil, constituting the letter, and the whole letter
is rendered visible at once.” This table is placed at one station, and
the electrical machine at the other, with 72 wires inclosed in a glass
tube connecting the two stations. He could have operated with equal
efficiency by using 37 wires having one wire for a common communicating
wire, or with 36 wires by substituting the ground for his common wire.
It does not appear that it was ever tested to any extent.
_Dr. Salva’s Electric Spark Telegraph._
In 1798, Dr. Salva, in Madrid, constructed a similar telegraph, as that
suggested by Reizen, (see Voigt’s Magazine, vol. 11, p. 4.) The Prince
of Peace witnessed his experiments with much satisfaction, and the
Infant Don Antonio engaged with Dr. Salva in improving his instruments.
It is stated that his experiments were conducted through many miles. No
description of his plans appear to have been given to the public.
_Origin of Galvanism._
Galvanism takes its name from Galvani, Professor of Anatomy at Bologna,
who discovered it in the year 1790. As the account of the circumstances
attending the discovery of this useful and wonderful agent, may not
be uninteresting to the reader, we insert it here as related in the
“_Library of Useful Knowledge_.”
“It happened in the year 1790, that his wife, being consumptive, was
advised to take, as a nutritive article of diet, some soup made of
the flesh of frogs. Several of these animals, recently skinned for
that purpose, were lying on a table in the laboratory, close to an
electrical machine, with which a pupil of the Professor was amusing
himself in trying experiments. While the machine was in action, he
chanced to touch the bare nerve of the leg of one of the frogs with
the blade of the knife that he held in his hand; when suddenly the
whole limb was thrown into violent convulsions. Galvani was not present
when this occurred, but received the account from his lady who had
witnessed, and had been struck with the singularity of the appearance.
He lost no time in repeating the experiment: in examining minutely
all the circumstances connected with it, and in determining those
on which its success depended. He ascertained that the convulsions
took place only at the moment when the spark was drawn from the prime
conductor, and the knife was at the same time in contact with the
nerve of the frog. He next found that other metallic bodies might be
substituted for the knife, and very justly inferred that they owed
this property of exciting muscular contractions to their being good
conductors of electricity. Far from being satisfied with having arrived
at this conclusion, it only served to stimulate him to the farther
investigation of this curious subject; and his perseverance was at
length rewarded by the discovery, that similar convulsions might be
produced in a frog, independently of the electrical machine, by forming
a chain of conducting substances between the outside of the muscles
of the leg, and the crural nerve. Galvani had previously entertained
the idea, that the contractions of the muscles of animals were in some
way dependent on electricity; and as these new experiments appeared
strongly to favour this hypothesis, he with great ingenuity applied it
to explain them. He compared the muscles of a living animal to a Leyden
phial, charged by the accumulation of electricity on its surface, while
he conceived that the nerve belonging to it, performed the function of
the wire communicating with the interior of the phial, which would, of
course, be charged negatively. In this state, whenever a communication
was made by means of a substance of high conducting power between
the surface of the muscle and the nerve, the equilibrium would be
instantly restored, and a sudden contraction of the fibres would be the
consequence.
“Galvani was thus the first to discover the reason of that peculiar
convulsive effect which we now obtain from the Galvanic battery, and he
attributed it to a modification of electricity. It was left to another
to construct an instrument which would give a constant and increased
effect, and develop this extraordinary fluid. Whatever share accident
may have had in the original discovery of Galvani, it is certain that
the invention of the Pile, an instrument which has most materially
contributed to the extension of our knowledge in this branch of
physical science, was purely the result of reasoning.
“Professor Volta, of Pavia, in 1800, was led to the discovery of its
properties by deep meditation on the developements of electricity at
the surface of contact of different metals. We may justly regard this
discovery as forming an epoch in the history of galvanism; and since
that period, the terms Voltaism, or Voltaic electricity, have been
often, in honour of this illustrious philosopher, used to designate
that particular form of electrical agency.
“He had been led by theory to conceive that the effect of a single pair
of metallic plates might be increased, indefinitely, by multiplying
their number, and disposing them in pairs, with a less perfect
conducting substance between each pair. For this purpose he provided
an equal number of silver coins, and of pieces of zinc, of the same
form and dimensions, and also circular discs of card, soaked in salt
water, and of somewhat less diameter than the metallic plates. Of these
he formed a pile or column as shown in figure 35, in which three
substances, silver, zinc, and wet card, denoted by the letters S, Z, I,
were made to succeed one another in the same regular order throughout
the series. The efficacy of this combination realized the most sanguine
anticipations of the discoverer. If the uppermost disc of metal in
the column be touched with the finger of one hand, previously wetted,
while a finger of the other hand is applied to the lowermost disc,
a distinct shock is felt in the arms, similar to that from a Leyden
phial, or still more nearly resembling that from an electrical battery,
weakly charged. These discs are supported by two large discs, _a_ and
_i_, of wood, one at the bottom and the other at the top of the pile,
with three glass rods, A, B, C, at equal distances around the pile, but
not touching it, and are cemented into the wooden base and cover. P
represents the wire connecting the silver disc, and N that connecting
the zinc.”
[Illustration: Fig. 35.]
_The Decomposition of Water._
“The chemical agency of galvanism, exerted on _fluid_ conductors,
placed in the circuit between the poles of the battery, is very
remarkable. Among the simplest of its effects is the resolution of
water into its two gaseous elements, oxygen and hydrogen. The discovery
of this fact is due to the united researches of Mr. Nicholson and Mr.
Carlisle, and was one of the immediate consequences of the invention
of the pile by Volta. The most convenient mode of exhibiting the
decomposition of water by the Voltaic battery, is to fill, with water,
a glass tube; to each end of which, a cork has been fitted so as to
confine the water, and to introduce into the tube two metallic wires,
by passing one, at each end, through the cork which closes it, allowing
the extremities of the wires, that are in the water, to come so near
each other as to be separated by an interval of only a quarter of an
inch. The wires being then respectively made to communicate with each
of the two poles of a Voltaic battery, the following phenomena will
ensue. If the wire connected with the positive pole of the battery
consists of an oxidable metal, it is rapidly oxidated by the water
surrounding it; while, at the same time, a stream of minute bubbles of
hydrogen gas arises from the surface of the other wire, which is in
connection with the negative pole. But if we employ wires made of a
metal which is not susceptible of oxidation by water, such as gold or
platina, gas will be extricated from both the wires, and, by means of a
proper apparatus may be collected separately.”
We shall now see that these two discoveries, viz. the Voltaic pile, and
the decomposition of water by the agency of the former are the bases of
a plan _for telegraphic_ purposes.
_Samuel Thomas Soemmering’s Description of his Voltaic Electric
Telegraph, invented in 1809._
[Illustration: FIG. 36.]
“The fact that the decomposition of water may be produced with
certainty and instantaneously, not only at short, but at great
distances from the Voltaic pile, and that the decomposition may be
sustained for a considerable time, suggested to me the idea, that it
might be made subservient for the purposes of transmitting intelligence
in a manner superior to the plan in common use, and would supersede
them. My engagements were such that I have only been able to test the
practicability of my plan upon a small scale, and herewith submit, for
the Academy’s publication, an account of the experiment.
“My telegraph was constructed and used in the following manner:
In the bottom of a glass reservoir, figure 36, of which A A is a
sectional view, are 35 golden points, or pins, passing up through
the bottom of the glass reservoir, marked A, B, C, &c. 25 of which
are marked with the 25 letters of the German alphabet and the ten
numerals. The 35 points are each connected with an extended copper
wire, soldered to them, and extending through the tube, E, to the
distant station; are there soldered to the 35 brass plates, upon the
wooden bar, K K. Through the front end of each of the plates, there
is a small hole, I, for the reception of two brass pins, B and C; one
of which is on the end of the wire connecting the positive pole, and
the other the negative pole of the Voltaic column, O. Each of the 35
plates are arranged upon a support of wood, K K, to correspond with
the arrangement of the 35 points at the reservoir, and are lettered
accordingly. When thus arranged, the two pins from the column are held,
one in each hand, and the two plates being selected, the pins are
then put into their holes and the communication is established. Gas
is evolved at the two distant corresponding points in an instant. For
example, K and T. The peg on the hydrogen pole, evolves hydrogen gas,
and that on the oxygen pole, oxygen gas.
“In this way every letter and numeral may be indicated at the pleasure
of the operator. Should the following rules be observed, it will enable
the operator to communicate as much if not more, than can be done by
the _common telegraph_.
“_First Rule._ As the hydrogen gas evolved is greater in quantity than
the oxygen, therefore, those letters which the former gas represents,
are more easily distinguished than those of the latter, and must be so
noted. For example, in the words _ak_, _ad_, _em_, _ie_, we indicate
the letters _A_, _a_, _e_, _i_, by the hydrogen; _k_, _d_, _m_, _e_, on
the other hand, by the oxygen poles.
“_Second Rule._ To telegraph two letters of the same name, we must use
a unit, unless they are separated by the syllable. For example, the
name _anna_, may be telegraphed without the unit, as the syllable _an_,
is first indicated and then _na_. The name _nanni_, on the contrary,
cannot be telegraphed without the use of the unit, because _na_ is
first telegraphed, and then comes _nn_, which cannot be indicated in
the same vessel. It would, however, be possible to telegraph even three
or more letters at the same time by increasing the number of wires from
25 to 50, which would very much augment the cost of construction and
the care of attendance.
“_Third Rule._ To indicate the conclusion of a word, the unit 1 must
be used. Therefore, it is used with the last single letter of a word,
being made to follow the ending letter. It must also be prefixed to
the letter commencing a word, when that letter follows a word of _two
letters_ only. For example: _Sie lebt_ must be represented _Si_, _e1_,
_le_, _bt_, that is the unit 1 must be placed after the first _e_. _Er
lebt_, on the contrary, must be represented. _Er_, _1l_, _eb_, _t1_;
that is, the unit 1 is placed before the _l_. Instead of using the
unit, another signal may be introduced, the cross † to indicate the
separation of syllables.
“Suppose now the decomposing table is situated in one city, and the
pin arrangement in another, connected with each other by 35 continuous
wires, extended from city to city. Then the operator, with his Voltaic
column and pin arrangement at one station, may communicate intelligence
to the observer of the gas at the decomposing table of the other
station.
“The metallic plates with which the extended wires are connected
have conical shaped holes in their ends; and the pins attached to
the two wires of the Voltaic column are likewise of a conical shape,
so that when they are put in the holes, there may be a close fit,
prevent oxidation and produce a certain connection. It is well known
that slight oxidation of the parts in contact will interrupt the
communication. The pin arrangement might be so contrived as to use
permanent keys, which for the 35 plates or rods would require 70 pins.
The first key might be for hydrogen A; the third key for hydrogen B;
the fourth key for oxygen B, and so on.
“The preparation and management of the Voltaic column is so well known,
that little need be said except that it should be of that durability
as to last more than a month. It should not be of very broad surfaces,
as I have proved, that six of my usual plates (each one consisting
of a Brabant dollar, felt, and a disc of zinc, weighing 52 grains)
would evolve more gas, than five plates of the great battery of our
Academy.[19] As to the cost of construction, this model which I have
had the honour to exhibit to the Royal Academy, cost 30 florins. One
line consisting of 35 wires, laid in glass or earthen pipes, each wire
insulated with silk, making each wire 22,827 Parisian feet, or a German
mile, or a single wire of 788,885 feet in length, might be made for
less than 2000 florins, as appears from the cost of my short one.”
[19] Academy of Sciences at Munich.
_Extract from the Journal of the Franklin Institute, vol. 20, page 325._
“To the foregoing notice, we append an article published in Thompson’s
Annals of Philosophy, vol. 7, page 162, 1st series, February, 1816.
This article is from the pen of Dr. John Redman Coxe, of Philadelphia,
and it is believed that the idea of the employment of galvanism,
for a telegraph which it suggests, was then original. Those who are
acquainted with the history of the progress of electricity, as evolved
by the ordinary machine, are aware that experiments had been made with
a view to its employment for a similar purpose; but from the inherent
difficulties of the subject, the project had been abandoned.
“It is not pretended, that the state of our knowledge on the subject
of galvanism, was such at the time the foregoing suggestion was made,
as would have enabled any person to apply it practically; this, if
done, will be due to the recent discoveries on the subject of electro
magnetism; a subject which has been very successfully pursued by the
philosophers of our own country, and particularly by Professor Henry,
of Princeton. As some of the philosophers of Europe are disputing upon
the question of the authorship of _proposition_ for the employment of
Galvanic electricity, telegraphically, we have thought that it would
not be altogether inopportune, or uninteresting, to publish the article
above referred to.
“_Use of Galvanism as a Telegraph: in an extract of a Letter from Dr.
J. Redman Coxe, Professor of Chemistry, Philadelphia._
“I observe in one of the volumes of your Annals of Philosophy, a
proposition to employ galvanism, as a solvent, for the urinary
calculus, but which has been very properly, I think, opposed by Mr.
Armiger. I merely notice this, as it gives me the opportunity of
saying, that a similar idea was maintained in a thesis, _three years_
ago, by a graduate of the University of Pennsylvania. I have, however,
contemplated this important agent, as a probable means of establishing
telegraphic communications, with as much rapidity, and perhaps less
expense, than any hitherto employed. I do not know how far experiment
has determined galvanic action, to be communicated by means of wires;
but there is no reason to suppose it confined, as to limits, certainly
not as to time. Now, by means of apparatus, fixed at certain distances,
as telegraphic stations, by tubes, for the _decomposition_ of _water_,
and of metallic salts, &c. regularly ranged, such a key might be
adopted as would be requisite to communicate words, sentences, or
figures, from one station to another, and so on to the end of the line,
I will take another opportunity to enlarge upon this, as I think it
might serve many useful purposes; but like all others, it requires
time to mature. As it takes up little room, and may be fixed in
private, it might, in many cases, of besieged towns, &c. convey useful
intelligence, with scarcely a chance of detection by the enemy. However
fanciful in speculation, I have no doubt that sooner or later, it will
be rendered useful in practice.”
“I have thus, my dear sir, ventured to encroach upon your time, with
some crude ideas, that may serve to elicit some useful experiments
in the hands of others. When we consider what wonderful results have
arisen from the first trifling experiments of the junction of a small
piece of silver and zinc in so short a period, what may not be expected
from the further extension of galvanic electricity: I have no doubt of
its being the chiefest agent, in the hands of nature, of the mighty
changes that occur around us. If the metals are compound bodies, which
I doubt not, will not this active principle combine those constituent
in numerous places, so as to explain their metallic formation? and
if such constituents are in themselves aeriform, may not galvanism
reasonably tend to explain the existence of metals in situations to
which their specific gravities certainly do not entitle us to look for
them?”
_Ronald’s Electric Telegraph, invented in 1816. From the Encyclopedia
Britannica, 7th edition, page 662._
“M. Cavællo suggested the idea of conveying intelligence by passing a
given number of sparks through an insulated wire in given spaces of
time; and some German and American authors have proposed to construct
galvanic telegraphs by the decomposition of water. Mr. Ronalds, who has
devoted much time to the consideration of this form of the telegraph,
proposes to employ common electricity to convey intelligence along
insulated and buried wires, and he proved the practicability of such a
scheme, by insulating eight miles of wire on his lawn at Hammersmith.
In this case the wire was insulated in the air by silk strings. But he
also made the trial with 525 feet of buried wire; with this view he dug
a trench four feet deep, in which he laid a trough of wood two inches
square, well lined within and without with pitch; and within this
trough were placed thick glass tubes, through which the wire ran. The
junction of the glass tubes was surrounded with shorter and wider tubes
of glass, the ends of which were sealed up with soft wax.
“Mr. Ronalds now fixed a circular brass plate, figure 37, upon the
second arbour of a clock which beat dead seconds. This plate was
divided into twenty equal parts, each division being worked by a
figure, a letter, and a preparatory sign. The figures were divided into
two series of the units, and the letters were arranged alphabetically,
omitting J, Q, U, W, X and Z. In front of this was fixed another
brass plate as shown in figure 38, which could be occasionally turned
round by the hand, and which had an aperture like that shown in the
figure at V, which would just exhibit one of the figures, letters and
preparatory signs, for example, 9, _v_, and ready. In front of this
plate was suspended a pith ball electrometer, B, C, figure 38, from a
wire D, which was insulated, and which communicated on one side with a
glass cylinder machine, and on the other side with the buried wire. At
the further end of the buried wire, was an apparatus exactly the same
as the one now described, and the clocks were adjusted to as perfect
synchronism as possible.
[Illustration: FIG. 37. FIG. 38.]
“Hence it is manifest, that when the wire was _charged_ by the machine
at either end, the electrometers at both ends _diverged_, and when it
was discharged, they collapsed, at the same instant. Consequently, if
it was discharged at the moment when a given letter, figure, and sign
on the lower plate, figure 37, appeared through the aperture, figure
38, the same figure, letter and sign would appear also at the other
clock; so that by means of such discharges at one station, and by
marking down the letters, figures and signs, seen at the other, any
required words could be spelt.
“An electrical pistol was connected with the apparatus, by which a
spark might pass through it when the sign _prepare_ was made, in order
that the explosion might excite the attention of the superintendent,
and obviate the necessity of close watching.
_“Preparatory signs._ A, prepare; V, ready; S, repeat sentence; P,
repeat word; N, finish; L, annul sentence; I, annul word; G, note
figures; E, note letters; C, dictionary.”
_Electro Magnetism._
We have now to notice a discovery, which forms the basis of those
modern telegraphs in which the principle of electro magnetism is
adopted. The following is an extract from the “Library of Useful
Knowledge,” in relation to the discovery:
“The real discoverer of the magnetic properties of electric currents
M. Oersted, Professor of Natural Philosophy, and Secretary of the
Royal Society of Copenhagen. In a work which he published in the
German, about the year 1813, on the identity of chemical and electrical
forces, he had thrown out conjectures concerning the relations
subsisting between the electric, galvanic and magnetic fluids, which
he conceived might differ from one another only in their respective
degrees of tension. If galvanism, he argued, be merely a more latent
form of electricity, so magnetism may possibly be nothing more than
electricity in a still more latent form; and he, therefore, proposed it
as a subject worthy of inquiry, whether electricity employed in this,
its most latent form, might not be found to have a sensible effect
upon a magnet. It is difficult clearly to understand what he meant
by the expression of _latent states_, as applied to electricity, but
it may be sufficient for us to know, that in the various endeavours
he subsequently made to verify his conjectures, he was led to such
forms of experiment as afforded decisive indications of the influence
of Voltaic currents on the magnetized needle. Yet, even after he had
succeeded thus far, it was a matter of extreme difficulty to determine
the real direction of this action, and it was not till the close of the
year 1819, that his perseverance was at length rewarded by complete
success.
“The first account of his discovery that appeared in England is
contained in a paper, which he himself communicated, in Thompson’s
Annals of Philosophy, for October, 1820, vol. 16, page 273; and in
which the following experiments are described. The two poles of a
powerful Voltaic battery were connected by a metallic wire, so as to
complete the galvanic circuit. The wire which performs this office
he called the _uniting_ wire; and the effect, whatever it may be,
which takes place in this conductor, and in the space surrounding
it, during the passage of the electricity, he designates by the term
_electric_ conflict, from an idea that there takes place some continued
collision and neutralization of the two species of electric fluids,
while circulating in opposite currents in the apparatus. Then taking a
magnetic needle, properly balanced on its pivot, as in the mariner’s
compass, and allowing it to assume its natural position in the magnetic
meridian, he placed a straight portion of the uniting wire horizontally
above the needle, and in a direction parallel to it; and then completed
the circuit, so that the electric current passed through the wire.
The moment this was done, the needle changed its position, its ends
deviating from the north and south towards the east and west, according
to the direction in which the electric current flowed, so that by
reversing the direction of the current the motion of the needle was
also reversed. The general law he expressed as follows: ‘That end of
the needle which is situated next to the negative side of the battery,
or towards which the current of positive electricity is following,
immediately moves to the westward.’
“The deviation of the needle is the same, whether the uniting wire,
instead of being immediately above the needle, be placed somewhat to
the east or west of it, provided it continue parallel to and also above
it. This shows that the effect is not the result of a simple attractive
or repulsive influence, for the same pole of the magnetic needle which
approaches the uniting wire, when placed on its east side, recedes from
it when placed on its west side.”
[20]“Soon after this important discovery of Oersted’s was made, M.
Ampère established the second fundamental law of electro magnetism,
that the two conducting wires from the poles of the battery, when
conveniently suspended, _attracts each other when they transmit
electrical currents moving in the same direction, and repel each other
when the currents which they transmit have opposite directions_.
[20] Encyclopedia Britannica, vol. 21, p. 686.
“On the 25th Sept. 1820, M. Arago communicated to the French Institute
the important discovery that the electrical current possesses, in a
very high degree the power of developing magnetism in iron or steel.
Sir H. Davy communicated a similar fact to Dr. Wollaston on the 12th of
November, 1820, and Dr. Seebeck laid before the Royal Academy of Berlin
a series of experiments on the same subject.
“M. Arago found that the uniting wires of a powerful Voltaic battery
attracts iron filings often with such force as to form a coating around
the wire ten or twelve times thicker than itself. This attraction, as
he found, did not originate in any magnetism previously possessed by
the iron filing, which he ascertained would not adhere to iron, and
that it was not a case of common electrical attraction, was evident
from the fact that copper and brass filings were not attracted by the
uniting wire. M. Arago likewise found, that the iron filings began to
rise before they came in contact with the uniting wire; and hence he
drew the conclusion, that the electric currents converted each small
piece of iron into a temporary magnet. In following out this view,
the French philosopher converted large pieces of iron into temporary
magnets and also small steel needles into permanent ones, (by employing
the helix.) Sir H. Davy and Dr. Seebeck obtained analogous results
without knowing what had been previously done in France.
“A galvanometer was first constructed by Professor Schweigger, of
Halle, very soon after the first discovery of electro magnetism, and by
him called an _electro_ magnetic multiplier.”
In the year 1820, Ampère predicted the possibility of making the
deflection of the magnetic needle, by the agency of the galvanic fluid,
serve the purposes of transmitting intelligence. In page 19 of his
memoir, he thus resolves the problem:
“As many magnetic needles as there are letters of the alphabet,” he
says, “which may be put in action by conductors; which may be made
to communicate successively with the battery by means of keys; which
may be pressed down at pleasure, might give place to a telegraphic
correspondence which would surmount all distance and would be as prompt
as writing speech to transmit thought.”
“The next step in the progress of discovery, was that of making magnets
of extraordinary power by means of a galvanic battery. This seems to
have been first accomplished by Prof. Moll, of Utrecht, and Professor
Henry, of Princeton, who was able to lift thousands of pounds weight by
his apparatus.”
_The following Extract is taken from a Work on Electro Magnetism
published by Jacob Green, M. D. Professor of Chemistry in Jefferson
Medical College, 1827._
“In the very early stage of electro magnetic experiments, it had been
suggested, that an instantaneous telegraph might be constructed by
means of conjunctive wires, and magnetic needles. The details of this
contrivance are so obvious, and the principles on which it is founded
so well understood, that there was only one question which could render
the result doubtful. This was, whether by lengthening the conjunctive
wires, there would be any diminution in the electrical effect upon the
needle. It is the general opinion, that the electrical fluid, from a
common electrical battery, may be transmitted, without any sensible
diminution, instantaneously, through a wire three or four miles in
length. At the philosophical dinner, as it has been called, got up a
number of years ago by some gentlemen of Philadelphia, on the banks of
the Schuylkill, it may be recollected that Dr. Franklin killed a turkey
with the electric shock, transmitted across the river, a distance of
more than half a mile; and Dr. Watson, who was also at the pains of
making some experiments of this kind, asserts that the electric shock
was transmitted, instantaneously, through the length of 12,276 feet.
Had it been found true that the galvanic fluid could be transmitted in
a moment through a great extent of conducting wire, without diminishing
its magnetic effect then no question could have been entertained
as to the practicability and importance of the suggestion adverted
to above, with regard to the telegraph. Mr. Barlow, of the Royal
Military Academy, who has made a number of successful experiments and
investigations in electro magnetism, fully ascertained that there was
so sensible a diminution with only 200 feet of wire, as to convince him
at once of the impracticability of the scheme.
_Triboaillet’s Proposition._
[21]“In 1828, M. Victor Triboaillet de Saint Amand proposed to
establish a correspondence from Paris to Brussels, by placing along
the highway, and at some feet deep, a metallic wire, about a line or a
line and a half diameter. He recommended to cover the wire with shellac,
upon which was to be wound silk, very dry, which should be covered in
their turn with a coating of resin. The whole was then to be put into
glass tubes carefully luted up with a resinous substance and secured
by a last envelope in the earth, then varnished over and hermetically
sealed. Then, by means of a powerful battery, he would communicate the
electricity to the conducting wire, which would transmit the current
to the opposite point to an electroscope, destined to render sensible
the slightest influence, and left to each one to adopt at pleasure the
number of motions to express the words or letters which they might
need.”
[21] Report of Academy of Industry, Paris.
_Fechner’s Suggestion._[22]
“Fechner, in his manual of galvanism, (Voss, 1829, page 269,) remarked,
that the electro magnetic effects of the galvanic current would be far
more appropriate for the giving of signs than Soemmering’s plan by the
decomposition of water.”
He suggested that wires, having twenty-four multiplicators should be
extended between Leipsic and Dresden, and there connected, alternately,
with a galvanic column, for telegraphic purposes. Indeed, he ventured
to prophecy, that probably hereafter such a connection between the
central point of a kingdom, and different provinces might be arranged
as there was existing in animal bodies, between the central point of
organic structure of particular members and nerves.
[22] Polytechnic Central Journal, 1838.
_Magneto Electricity._
We come now to give an account of a new branch in the science of
electricity, viz. _magneto electricity_; which Dr. Faraday was the
first to discover in the year 1831. As this species of electricity has
been applied to several of the plans of electric telegraphs, which we
shall describe, it is desirable that some account should be given of
its discovery, and of the instrument by which it is generated.
The following is an extract from “Daniell’s Introduction to Chemical
Philosophy” 2d edition, London, 1843.
“The phenomena of electro magnetism are produced by _electricity in
motion_; accumulated electricity, when _not in motion_, exerts no
magnetic effects. Dr. Faraday early felt convinced that “as every
electric current is accompanied by a corresponding intensity of
magnetic action at right angles to the current, good conductors of
electricity, when placed within the sphere of this action, should have
a current induced through them, or some sensible effect produced,
equivalent in force to such a current.” These considerations, with
their consequence, the hope of obtaining electricity from ordinary
magnetism, stimulated him to investigate the subject experimentally,
and he was rewarded by an affirmative answer to the question proposed.
He thus became, like Oersted, the founder of an entirely new branch of
natural philosophy.
“If a wire connecting the two ends of a delicate galvanometer be
placed parallel and close to the wire connecting the poles of a
Voltaic battery, no effect will be produced upon the needle, however
powerful the current may be. If the points opposed in the two wires be
multiplied by coiling the one, as a helix, _within the convolutions_
of the other, coiled in the same way, both being covered with silk to
prevent metallic contact, still no effect will be discernible so long
as the current is _uninterrupted_. When, however, the current of the
battery is stopped by breaking the circuit, the needle is momentarily
deflected, as by a wave of electricity passing in the same direction
as that of the main current. Upon allowing the needle to come to a
state of rest, and then renewing the contact, a similar impulse will
be given to it in the contrary direction. While the current continues,
the needle returns to its state of rest, again to be deflected in the
first direction by stopping the current. Motion may be accumulated to a
considerable amount in the needle, by making and breaking the contacts
with the battery in correspondence with its swing. The same effects are
produced when, the current being uninterrupted, the conducting wire is
made suddenly to approach or recede from the wire of the galvanometer.
As the wires approximate, there will be a momentary current induced
in the direction contrary to the inducing current; and as the wires
recede, an induced current in the same direction as the inducing
current.
“As this _Volta electric induction_ is obviously produced by the
transverse action of the Voltaic current, in one case, by the
_mechanical_ motion of the wire, and in the other at the moments of
_generation_ and _annihilation_ of the current, Dr. Faraday thought
that the sudden induction and cessation of the same magnetic force in
soft iron, either by the agency of a Voltaic current, or by that of
a common magnet, ought to produce the same results. He constructed
a combination of helices (8) upon a hollow cylinder of pasteboard:
they consisted of lengths of copper wire, containing, altogether,
220 feet; four of these were connected end to end, and then with the
galvanometer. The other intervening four were also connected end to
end, and then with the Voltaic battery. In this form a slight effect
was produced upon the needle by making and breaking contact. But
when a soft iron cylinder, seven-eighths of an inch thick and twelve
inches long, was introduced into the pasteboard tube, surrounded by
the helices, the induced current affected the galvanometer powerfully.
When the iron cylinder was replaced by an equal cylinder of copper, no
effect beyond that of the helices alone was produced.
“Similar effects were then produced by _ordinary magnets_. The hollow
helix had all its elementary helices connected with the galvanometer,
and the soft iron cylinder having been introduced into its axis, a
couple of bar magnets were arranged with their opposite poles in
contact, so as to resemble a horse-shoe magnet, and contact was then
made between the other poles and the ends of the iron cylinder, by
which it was converted, for the time, into a magnet; by breaking
the magnetic contacts, or reversing them, the magnetism of the iron
cylinder could be destroyed or reversed at pleasure. Upon making
magnetic contact, the needle was deflected; continuing the contact,
the needle became indifferent, and resumed its first position; on
breaking contact, it was again deflected, but in the opposite direction
to the first effect, and then it again became indifferent. When the
magnetic contacts were reversed, the deflections were reversed. The
actual contacts of the magnets with the soft iron is not essential
to the success of these experiments, for their near approximation
induces sufficient magnetism in the cylinder to generate the electric
current, which affects the needle. The first rise of the magnetic
force induces the electric wave in one direction; its sudden decline,
in the opposite. Mechanical motion of a permanent magnetic pole in
one direction, across the coils of the helix, will produce the same
effect as the sudden induction of the magnetism in the soft iron, and
its motion in the opposite direction will cause a corresponding effect
with its annihilation, when the soft iron cylinder is removed from
the helix, and one end of a cylindrical magnet thrust into it, the
needle is deflected in the same way as if the magnet had been formed,
by either of the two preceding processes. Being left in, the needle
will resume its first position, and then being withdrawn, the needle
will be deflected in the opposite direction. On substituting a small
hollow helix, formed round a glass tube, for the galvanometer, in these
experiments, and introducing a steel needle, it will be converted into
a magnet, provided care be taken not to expose it to the opposite
action of the reverse current; and if the continuity of the conducting
wire be broken, at the moment when the secondary electric wave is
passing through it, a bright spark may be obtained.
“The connection of electro magnetical and magneto electrical phenomena
may be exhibited in a very striking way, by employing any of the
apparatus, by which the rotary motions of the _magnet_ or _conducting
wire_, are produced by a current of electricity, to generate electric
currents by the mechanical rotations of the magnet or wire. For this
purpose, the galvanometer may be substituted for the battery, and
when the wire is made to turn round the pole of the magnet, or the
pole of the magnet round the wire, in one direction, the needle will
be deflected to one side; and to the other by the opposite rotation.
Nothing can be better shown that _magneto electric_ is the _converse_
of _electro_ magnetic action.
“Dr. Faraday by rotating a copper disc between the poles of a
horse-shoe magnet, produced a constant current of electricity in one
direction, and deflected the needle of the galvanometer; one wire being
connected with the disc, and the other with the arbour. By turning
the disc in one direction, the circuit will pass from the axis to the
circumference; by turning it in the opposite direction, the current
will flow from the circumference to the axis.”
[Illustration: FIG. 39.]
Figure 39 represents a side view of the instrument. B shows the copper
disc permanently secured upon its axis, and which is turned by means
of the crank, E. G represents one of the standards which support the
axis. H is the platform upon which the various parts are arranged. The
edge, C, of the copper disc, is amalgamated so as to make a perfect
connection with the amalgamated segment, _a_, to which is soldered a
wire, I, leading to the galvanometer. That portion of the disc, B,
which is shaded, is not amalgamated. J is the other wire proceeding
from the galvanometer, and both it and the axis are amalgamated, at the
points of connection. A is the permanent magnet, with its poles on each
side of the copper disc, B, opposite the amalgamated portion of the rim.
[Illustration: FIG. 40.]
Figure 40, represents a top view of the instrument, H is the platform;
C the disc; _a_ the segment; A the permanent magnet; J the wire
attached to the axis, P; G and G are the two standards. E the crank;
and I the wire attached to the segment _a_.
Mr. Saxton,[23] in a letter to Mr. Lukens, dated, London, April 14th,
1832, after describing Dr. Faraday’s rotating disc, figures 39 and 40,
says, “I have made this experiment in a different way, and succeeded
satisfactorily. The method was as follows: A coil of wire wrapped
with silk, similar to that used in the galvanometer, was attached,
by the ends, to the wires of the galvanometer. On passing this roll,
backward and forward, upon one of the poles of a horse-shoe (permanent)
magnet, or placing it upon and removing it from either pole, I have
made the needle of the galvanometer to spin round rapidly.” Figure 41,
represents Mr. Saxton’s plan.
[23] We here introduce to the reader our ingenious and scientific
country man, Mr. Joseph Saxton, formerly of the United States mint,
Philadelphia, but now connected with the Department of weights and
measures, at Washington, who invented the first Rotary Magneto Electric
Machine, and which has now been extensively adopted.
[Illustration: FIG. 41.]
N and S represent the north and south poles of the horse-shoe permanent
magnet. C is the coil of wire, wound round a spool of an oblong shape,
through the centre of which there is an opening sufficiently large
to admit either of the prongs of the magnet through it. A and B are
the ends of the wire leaving the coil, and are connected with the
galvanometer.
Mr. Saxton on the 2d of May, 1832, obtained the spark by the following
arrangement of the permanent magnet and the helix of wire round the
armature. In relation to this instrument, he thus writes to Mr. Lukens,
of Philadelphia, dated, London, May 11th, 1832. Jour. Frank. Int. vol.
13, p. 67. “Since my last I have heard of a method of producing a spark
from a magnet, discovered I think by an Italian.[24] This experiment I
made at once upon a large horse-shoe magnet, which I am making for Mr.
Perkins and his partners. One of your large magnets will answer the
same purpose. Make a cylinder of soft iron of an inch, or three-fourths
of an inch, in diameter, and of the usual length of the keeper; place
two discs of brass or wood upon this cylinder, and at such a distance
apart that they will conveniently pass between the poles of the magnet;
between these wind, say fifty feet of bobbin wire, which may be of iron
covered with cotton; let the ends of this coil be bent over the ends of
the cylinder and brought down until they touch the poles of the magnet.
The ends should be of such a length, that on bringing the cylinder to
the magnet, one of the ends will touch, when the cylinder is about
half an inch from the magnet, and the other at one-fourth of an inch.
The cylinder being thus arranged, and in contact with the magnet, on
drawing it suddenly away a spark will pass between the end of the wire,
and the pole of the magnet.”
[24] M. M. Nobili and Antinori.
[Illustration: FIG. 42.]
Figure 42 represents the instrument as first constructed by Mr. Saxton,
in London.[25] A and B are the ends of the helix, surrounding the
cylindrical bar of soft iron between E and F, filling the cavity which
has been formed out of the solid iron. The size of bar between the
collars E and F, thus formed, is the same as the projections H and
G. The wire, _a_, proceeds from the outside of the coil and makes a
suitable contact upon the prong, A, of the magnet: _b_ proceeds from
the bottom of the coil, where the winding commenced and makes a similar
contact upon the prong, B, of the permanent magnet. One wire extends
a little further upon the magnet than the other, so that the shorter
one may break its connection sooner than the longer. H and G are
projections from the sides of the armature, to which the handle, D, is
secured. Let the armature, with its helix, be held up against the ends
of the prongs of the permanent magnet; and the wires _a_ and _b_, in
perfect contact with their respective prongs, as shown in the figure;
if, while in this condition, the keeper is suddenly withdrawn, a spark
will appear at the end of the short wire, as it breaks its contact with
the prong of the magnet.
[25] Mr. Saxton on the 3d of May exhibited his apparatus, and the
mode of obtaining the spark to Dr. Ritchie, Messrs. Thomas Gill, John
Isaac Hawkens and Steadman Whitwell. On the 8th of May he loaned it
to Dr. Ritchie, who publicly exhibited it at a lecture, at the London
University, and also at the London Institution, Finsbury.
Mr. Saxton, however, was still further successful, the following year,
in carrying out an idea which occurred to him on the 6th of December,
1832, of producing the same phenomena, with a more convenient and
powerful rotating instrument.[26] This new arrangement he was able to
test on the 20th of June, 1833, and obtained the spark. On the 22d,
he made an unsuccessful attempt, in the presence of Prof. Rogers, of
Philadelphia, at the decomposition of water. On the 30th of June he
exhibited it at a meeting of the British Association at Cambridge,
before Dr. Faraday, Dr. Brewster, Prof. Forbes, Dr. Dalton, and many
other distinguished and scientific gentlemen. The experiments made by
it were the exhibition of the spark, giving shocks, &c. On the third
of July, Mr. Saxton succeeded in decomposing water, by adding a little
sulphuric acid, and on the 25th of August, he ignited and melted
platinum wire.
[26] In relation to this instrument, Prof. Daniell makes the following
remarks: “After Dr. Faraday’s discovery of _Volta electric_ and
_magneto electric_ induction, many ingenious contrivances were made for
exalting the effects and facilitating experiments. The most complete
arrangement now in use, was the original combination of Mr. Saxton.”
[Illustration: FIG. 43.]
Figure 43 exhibits a side view of the instrument: _a_, _a_, _a_, is
a compound permanent magnet, consisting of three steel plates, put
together, side by side. B and C are two wooden supports, upon the
platform A A. To these supports the magnet is permanently secured, by a
yoke, S, through which pass two screws into the wooden supports below.
M is a cross bar, into which, and at right angles with it, are screwed
two arms of round soft iron, R, about five-eighths of an inch in
diameter, the whole forming the armature or keeper of the magnet. Upon
these two projecting arms, are placed two coils, D′ and D, of copper
wire, insulated with silk. The whole is very securely fastened upon
the steel spindle, N, which has its journals in the supports, B and
B′. On the end of the spindle, N, near the curve of the magnet, there
is a small band pulley, F, which is driven by the band or cord of the
large wheel, E, and the crank, J. The axis of the large wheel passes
through a long socket, L, in the top of the column, H; on one end of
the axis the band wheel is fastened and on the other the crank. By
this arrangement a very rapid and quiet rotary motion is given to the
armature.
In the column, H, there is a socket, into which the stem of the upper
part of the column, G, is fitted, which admits of the large wheel being
raised or lowered, so as to prevent the band from slipping, and when
properly adjusted it is secured by the screw, I. O is an ivory hub,
sliding over that part of the spindle immediately projecting beyond
the cross bar, M. Upon this ivory hub is a copper disc, C, with a
socket, _n_: _b_, is a needle made of platinum, which, with its socket,
_m_, is nicely fitted upon the end of the steel spindle, so as to be
adjusted to any required angle with the armature, and when adjusted
to retain its position. The two ends of the two coils, which leave
the _centre_ of the helices, are made to form a contact with the soft
iron arms, R R, passing through the coils, D′ and D, thus making the
circuit complete with the needle _b_, upon the end of the spindle, N,
by a continuous metallic connection of the arms, with the cross bar,
M, and through the cross bar to the spindle, N, in contact with the
needle, _b_. The two ends of the two coils, leaving the _outside_ of
the helices, are joined in one, and as they pass through the cross bar,
M, are insulated from it, by a piece of ivory, inserted in the cross
bar. The united wire then passes into and through the ivory hub, _e_,
forming a perfect contact with the copper disc, _c_, underneath its
socket, _n_: _d_, is a cup of mercury, in which the copper disc, _c_,
is always immersed, and the needle, _b_, twice in every revolution of
the armature. The cup, _d_, is so constructed as to rise and fall, by
means of a stem, _i_, sliding vertically into a socket, _e_, of its
support, and is secured to its position by the screw, _h_. In this way,
its proper height for breaking and closing the circuit may be easily
obtained, when the armature is rotating. The proper position for the
needle, _b_, is that in which it is just leaving the mercury, as the
keeper arrives at the position, in which its magnetism is neutralized.
This position is seen at X, where D″ and D′ are the sides of the coils;
_c_ the copper disc; _m_ the cross bar of the armature; R the arm
passing through the coil; and _b_ the needle, at that _angle_ which it
requires, when the armature is vertical or at its neutral position. It
will be observed that the needle is just leaving the mercury, _d_.
[Illustration: FIG. 44.]
Figure 44 represents a top view. N and S represent the north and south
poles of the permanent magnet. N′ and N′ is the spindle, parallel with
the prongs of the magnet, and equidistant from them; L is the socket
of the band wheel; D′ and D the horizontal position of the coils; M is
the cross bar; _b_ the needle; _c_ the copper disc, and _m_ and _n_
their respective sockets; _o_ the ivory hub; _d_ the cup of mercury; A
the platform; and S′ and S′ the yoke through which pass two screws to
secure the magnet to the wooden support below.
When the armature is made to rotate, it becomes a temporary magnet, by
the laws of magnetic induction, whenever the arms carrying the helices
come opposite to the poles of the permanent magnet, and when these soft
iron arms have reached the point at _right angles_ to the _magnet_,
or vertical, their magnetism for an instant is destroyed, and are as
instantaneously reversed from what they were before reaching that
point. They are also magnetic, just in that proportion as they recede
from or approach to the poles of the permanent magnet.
Hence, first, _one arm_ is the south pole, when opposed to the north
pole of the magnet; and the _other arm_ a north pole, when opposed to
the south pole of the magnet. But when they have made a half revolution
on their axis, from their first position, their magnetism is reversed.
The arm which was a south pole, has become a north pole; and the arm
that was a north pole has become a south pole. Thus, by the rotation
of the armature, direction of the induced current in the arms, become
changed, as often as they are alternately brought opposite the poles
of the permanent magnet, which is _twice_ in every revolution of the
armature.
It follows, then, by the laws of magneto induction, that as often as
the arms become magnetic, they induce corresponding _opposite electric_
currents in the wire surrounding those arms, provided the circuit
of the coils is complete. The disc, which is in metallic connection
with two ends of the wire leaving the coils, (one from each coil,) is
_always_ immersed in the mercury of the cup. The needle, however, which
is in connection with the other two wires from the two coils, (one from
each coil,) is _not always_ immersed, but only when the armature is at
a certain position in relation to the permanent magnet. The circuit
then can only be closed when the needle is immersed, as well as the
disc. Upon inspecting the figure, it will be found that the needle is
immersed at the time the arms are passing the poles of the magnet, and
that when they arrive at the vertical or neutral position, the needle
has just broken its connection with the mercury, and at that instant
the spark is observed.
Professor Daniell observes, that “by means of this magneto electrical
machine, all the well known effects of Voltaic currents may be very
commodiously produced. When the communication is made between the
spindle and the revolving disc, by means of a fine platinum wire,
instead of the dipping points, the wire may be maintained at a red
heat; although the effect being produced by alternating currents in
opposite directions, a kind of pulsation, or intermission of the
light, may be discerned. Upon making the communication between the two
mercury cups, by means of copper cylinders _grasped_ in the _hands_, a
continued painful contraction of the muscles of the arm takes place,
which destroys voluntary motion, and, under certain circumstances, is
perfectly _intolerable_.
“The general expression of these phenomena may be thus stated: whenever
a piece of metal is passed, either before a single pole, or between the
opposite poles of a magnet, or before electro magnetic poles, whether
ferruginous or not, so as to cut the magnetic curves, (or lines, which
would be marked out by a spontaneous arrangement of iron filings,)
electrical currents are produced across the metal, transverse to the
direction of motion.”
_Dr. Page’s Magneto Electric Machine._
This important instrument also depends, for its action, upon the
principle discovered by Dr. Faraday, that electricity was developed
in conducting bodies, when they were moved in a certain direction,
in the neighbourhood of permanent magnets. Since the beautiful and
ingenious invention which Mr. Saxton was the first to make, no valuable
improvements have been made in this machine, except those introduced by
Professor Page.
The first important change in the machine, was the adaptation of his
pole changer to the machine, in place of the break pieces, which were
used in all the modifications up to that time; and another equally
useful improvement, consisted in the arrangement of the permanent
magnets and armatures. Previous to this last improvement, these
machines were constructed with a single permanent magnet, and one or
more revolving armatures, necessarily involving great disadvantages.
Page’s improvements were completed in February, 1838, and shortly after
published in Silliman’s Journal. He was also the first to suggest the
combination of several machines under one mechanical movement, as the
best mode of augmenting power in this way.
_The combined machine, described in Daniell’s Introduction to Chemical
Philosophy, as invented by Wheatstone, about two years since, is the
same as that described, and represented by Dr. Page in Silliman’s
Journal in 1838._ In the same publication, Dr. Page described the
arrangement of the permanent magnets and armatures, as shown in
the annexed figures. The adaptation of the pole changer, which, in
connection with this machine, is called the _Unitrep_, Dr. Page has
given to the public. But as he has never allowed the improvement, which
consists in the use of two or more permanent magnets and straight
armatures, to be sold with his knowledge and consent, he intends to
claim a _patent for the same_; it having been decided by our courts,
that the publication of an invention by the inventor, does not affect
his right to a patent, provided he does not allow the invention to be
sold and used.
The figures 45, 46 and 47, exhibit one of Page’s machines with his
early improvements.
Figure 45, is a side elevation of the machine.
Figure 46, is a top view.
Figure 47, are views of the revolving armatures and coils.
In Figure 45, representing a side view of the machine, B and B are the
compound permanent steel magnets, composed of six bars each of the U
form, mounted upon the brass pillars, P, P, P, P, which are fastened
into the common platform of the whole machine. Through the platform
there pass stout rods, R and R, and upwards through two brass straps,
above the magnets, B and B. These straps or yokes secure the magnets
from any motion by means of the screw nuts. A is a circular case of
pasteboard, containing the armatures and coils. H is a band wheel
surrounding the case, for mechanical connection with any source of
power that may be used to keep the machine in motion. I′ and I are
two metallic studs, with an aperture passing vertically from the top,
to the depth of an inch, for the reception of connecting wires, and
then, by means of a screw at its side, to make a perfect contact. There
are two other studs directly behind them. G and J are the two pulley
wheels, with their band and crank, by which a rapid rotary motion is
given to the armatures and coils. These pulleys are supported by the
standard. From the bottom of the studs I′ and I, as also from those
directly behind them, proceed wires which are carried along below
the platform, and pass up through it between the pilliar, P, and the
revolving armatures, to the shaft; there being one on each side of the
axis.
[Illustration: FIG. 45.]
[Illustration: FIG. 46.]
Figure 46, represents a top view of the instrument. A is the case
containing the armatures and coils, and H the band wheel. N, S and N,
S, are the north and south poles of the permanent magnets. S′ and S′
are the yokes by which the magnets are secured to the platform, and the
screws near the poles of the magnets are for the purpose of setting
the magnets to any required position, laterally, and securing them in
it. M and M are the tops of the two pilliars, which support the shaft
of the armatures and coils. The bearings are so made as to allow the
apparatus to revolve with as little friction as possible: 3 and 3
represent the set screws against the ends of the shaft, for adjusting
the ends of the permanent magnets; by which means, the armatures may
be allowed to pass very near the ends of the magnets without touching.
6, 7, 8, and 9 are the receiving studs, by which the wires from any
other instrument may be connected with the machine. The wire, _a_, in
contact with the unitrep, as before stated, is continued and soldered
to the receiving stud, 6; in the same manner, _c_, also in contact
with the unitrep, is connected with 7; and also 3 with 8; and _a_ with
9. The manner in which these wires, _a_, _c_, 3, and _a_, form their
contact with the shaft, is seen at N and P, figure 45, of which 5 and 5
represent a section of the shaft and unitrep.
[Illustration: FIG. 47.]
Figure 47 represents the revolving armatures and coils, with the
case taken off. C and C are the two coils of insulated copper wire,
surrounding two straight bars of soft iron, represented in the end view
by D and D. E is the shaft. The two armatures and coils are secured to
the two brass straps F, which are themselves fastened upon the shaft.
The armatures are allowed to project through the straps about the
sixteenth of an inch.
On each end of the shaft is attached an _unitrep_, consisting of
two cylindrical segments of silver, as seen at 5 and 5, figure 45;
insulated from each other, and secured to a cylinder of ivory or
wood, upon the shaft, so as to revolve with it. The terminations of
the coils of wire upon the armatures, are soldered to the segments
of silver, and as the unitrep turns, it brings opposite ends of the
wires, alternately, upon the stationary wires or conductors, P and N:
(in figure 46 they are represented by _a_ and _c_, and 3 and _a_.)
The opposing currents of the coils, in each half revolution, are, by
this contrivance, made to form one continuous current. Hence, the
name _unitrep_ (to turn together.) There being two unitreps, and
corresponding conducting wires, and screw cups, the induced currents
from the two coils may be combined in several ways, after the manner of
combining separate batteries.
Let the wires below the base board be all properly connected with the
receiving cups, as heretofore described. Then let the wire from 6,
(represented by dots,) to _k_, be connected with the wire 9 and _m_;
and also the wire 7 and _l_, with the wire 8 and 0. Let one of the
united wires be connected with one wire leaving the coil of an electro
magnet; and the other united wire be joined to the other wire of the
electro magnet of the telegraph, or any other instrument designed to
operate by a galvanic battery. When this preparation is finished,
if the armatures and coils are made to revolve rapidly, a powerful
current is formed in the induced coils, C and C, figure 47, capable of
performing all the experiments generally made by means of the galvanic
battery.
Dr. Page has made a very important discovery in connection with this
machine, not now to be made known; but, suffice it to say, the single
machine which he has now in his possession, on Christmas day, 1844,
operated Morse’s telegraph, through the circuit of 80 miles; half
this circuit being wire, the other half the earth. This machine makes
an electro magnet sustain 1000 pounds, and melts a platinum wire
one-fortieth of an inch in diameter.
_The Pole Changer._
We introduce here a description of an instrument used for reversing
the direction of the galvanic current, and which is applied in the
operation of several kinds of electric telegraphs. There is a variety
of modes by which the same object is attained, but as this appears the
most simple, we have chosen it in preference to others.
The following figures, 48, 49 and 50, are three views of the instrument
as it appears when looking down upon it, in its three changes. First,
that in which the current is broken and the needle vertical. Second,
in which the circuit is closed and the needle deflected to the right.
Third, in which the circuit is closed and the needle deflected to
the left. Each figure has, in connection with the pole changer, the
battery, or any other generator of the electric fluid, represented by N
and P, and the galvanometer represented by G. In each of the figures,
the circles numbered 1, 2, 3, 4, 5, 6, 7, and 8, represent cups, filled
with mercury, let into the wood of the platform, and made permanent.
The small parallel lines terminating in these cups, represent copper
wires or conductors.
[Illustration: FIG. 48.]
A, figure 48, represents a horizontal lever of wood, or some insulating
substance, with its axis supported by two standards, B and C, by which
it can easily vibrate. D represents an ivory ball, mounted upon a
rod, inserted in the lever, and extending a few inches above it. It
serves as a handle, by which to direct the elevation or depression of
either end of the lever. Both ends of the lever branch out, presenting
two arms each. Through each arm passes a copper wire, insulated from
each other. The left hand branches support the wires which connect
the mercury cups, 1 and 4, and 2 and 3, together. The right hand
branches support the wires which connect the cups 5 and 7, and 6 and
8, together. The ends of these wires directly over the mercury cups
are bent down, so that they may freely enter their respective vessels
when required. The other wires are permanently secured to the platform.
The position of the lever is now _horizontal_, and the bent ends of
the wires, which it carries, are so adjusted, that none of them touch
the mercury, consequently, there is no connection formed between the
battery and galvanometer, and the needle is _vertical_. The ivory ball,
it will be observed, is directly over the centre of the axis, and in
that position required to break the circuit. Thus, the wires, 2 and 3,
1 and 4, 5 and 7, 6 and 8, are each out of the mercury, and the circuit
being broken the fluid cannot pass.
[Illustration: FIG. 49.]
Figure 49 represents those connections which are formed when the left
hand side of the lever is depressed, immersing in the mercury those
wires supported by it. The ball and lever are omitted for the better
inspection of the wires. Now the circuit is closed, and the current
is passing from P, of the battery, to the mercury cup, 1; then along
the cross wire to 4; to 8; to the coils of the multiplier, deflecting
the needle to the _right_; then to 7; to 3; then along the cross wire,
(which is not in contact with wire 1 and 4,) to 2; to the N pole of the
battery. The arrows also show the direction of the current. It will be
observed that the cups 5 and 7, and 6 and 8 are not now in connection,
and consequently the current cannot pass along the wires 1 and 5, and 2
and 6.
[Illustration: FIG. 50.]
Now, if the ball, D, is carried to the right, a new set of wires,
figure 50, are immersed, and those represented in figure 49, as in
connection, are taken out of their cups. The fluid now passes from P,
of the battery, to the mercury cup, 1; to 5; to 7; to the coils of the
multiplier, deflecting the needle to the _left_; then it passes to
cup 8; to 6; to 2; and then to the N pole of the battery; the arrows
representing the direction of the current. It will now be found, that
the cups, 2 and 3, and 1 and 4 are not in connection, and consequently
the current cannot pass along the wires, 3 and 7, and 4 and 8.
Thus, it will appear, that by carrying the ball, D, to the left, the
needle is deflected to the _right_; then, by carrying the ball to the
right, the needle is deflected to the _left_; and that when the ball is
brought to the vertical position, the needle is _vertical_. These three
changes enter into the plans of several electric telegraphs, which are
to be hereafter described.
_Professor Morse’s American Electro Magnetic Telegraph, invented, 1832._
To our readers the principles and arrangement of Morse’s telegraph have
been fully explained in the former part of this work. We shall here
present _some_ of the evidence of the time of its invention.
_Extract from a letter from S. F. B. Morse to the Hon. Levi Woodbury,
Secretary of the Treasury, dated Sept. 27th, 1837._
“About five years ago, on my voyage home from Europe, the electrical
experiment of Franklin, upon a wire some four miles in length, was
casually recalled to my mind, in a conversation with one of the
passengers, in which experiment it was ascertained that the electricity
travelled through the whole circuit in a time not appreciable, but
apparently instantaneous. _It immediately occurred to me, that if the
presence of electricity could be made_ VISIBLE _in any desired part
of this circuit, it would not be difficult to construct a_ SYSTEM OF
SIGNS _by which intelligence could be instantaneously transmitted._ The
thought, thus conceived, took strong hold of my mind, in the leisure
which the voyage afforded, and I planned a system of signs and an
apparatus to carry it into effect. I cast a species of type, which I
had devised for this purpose, the first week after my arrival home; and
although the rest of the machinery was planned, yet, from the pressure
of unavailable duties, I was compelled to postpone my experiments,
and was not able to test the whole plan until within a few weeks. The
result has realized my most sanguine expectations.”
The following letters were published in the Journal of Commerce, from
the originals now in possession of Prof. Morse.
_Letter of the Hon. W. C. Rives._
SENATE CHAMBER, _September 21st, 1837_.
MY DEAR SIR,—I hope you will find in my
multiplied and oppressive engagements here, an apology for
not having sooner answered your inquiry on the subject
of your Electro Magnetic Telegraph. I retain a distinct
recollection of your having explained to me the conception
of this ingenious invention, during our voyage from France
to the United States in the year 1832, and that it was, more
than once, the subject of conversation between us, in which
I suggested difficulties which you met and solved with great
promptitude and confidence.
I beg leave to assure you, that it would give us all
great pleasure to renew, in personal intercourse at home,
the agreeable souvenirs of our acquaintance, and friendly
relations abroad.
I remain with great respect,
Your most obd’t serv’t,
W. C. RIVES.
PROF. S. F. B. MORSE.
_Letter of Capt. William W. Pell,
of the packet ship Sully._
NEW YORK, _Sept. 27th, 1837_.
DEAR SIR—On my arrival here I received your
letter, calling upon my recollection for what was said on
the subject of an electric telegraph, during the passage
from Havre, on board of the ship Sully, in October, 1832.
I am happy to say, I have a distinct remembrance of your
suggesting, as a thought newly occurred to you, the
possibility of a telegraphic communication being effected
by electric wires. As the passage progressed, and your
idea developed itself, it became frequently a subject of
conversation. Difficulty after difficulty was suggested
as obstacles to its operation, which your ingenuity still
labored to remove, until your invention, passing from its
first crude state through different grades of improvement,
was, in seeming, matured to an available instrument, wanting
only patronage to perfect it, and call it into reality; and
I sincerely trust that circumstances may not deprive you
of the reward due to the invention, which, whatever be its
source in Europe, is with you at least, I am convinced,
original.
When you observed to me a few days before leaving the
ship, “_well, Captain, when you hear of the telegraph one
of these days, as the wonder of the world, remember the
discovery was made on board the good ship Sully_,” I, then,
little thought, I should ever be called upon to throw into
the scale, my mite of testimony in support of your claims
to priority of invention, for what seemed so startling a
novelty.
With my respects and best wishes,
I subscribe myself,
WILLIAM W. PELL.
SAMUEL F. B. MORSE, ESQ.
A subsequent letter from Captain Pell, dated February 1st, 1838, after
having seen the operation of the telegraph at the University, has the
following paragraph:
“When, a few days since, I examined your instrument, _I recognized in
it the principles and mechanical arrangements_, which, on board, I had
heard you so _frequently explain_ through all their developments.”
From a letter now in possession of the author, and addressed to him by
Prof. Morse, we make the following extract:
“In 1826, the lectures, before the New York Atheneum, of Dr. J. F.
Dana, who was my particular friend, gave to me the first knowledge
ever possessed of electro magnetism; and some of the properties of
the _electro magnet_; a knowledge which I made available in 1832 as
the basis of my own plan of an electro telegraph. I claim to be the
original suggestor and inventor of the electric magnetic telegraph,
on the 19th of October, 1832, on board the packet ship Sully, on my
voyage from France to the United States, and, _consequently_, the
inventor of the first, really _practicable telegraph on the electric
principle_. The plan then conceived and drawn out in all its essential
characteristics, is the one now in successful operation. All the
telegraphs in Europe, which are practicable, are based on a different
principle, and, _without an exception_, were invented subsequently to
mine.
“The thought occurred to me, in a general conversation, as seated at
the table with the passengers, in which the experiments of Franklin
to ascertain the velocity of electricity through three or four miles.
The thought at once occurred to me that electricity might be made the
means of conveying intelligence, and that a system of signs might
easily be devised for the purpose. I ought, perhaps, to say, that the
conception of the idea of an _electric telegraph_, was original with
me at that time, and I supposed that I was the first that had ever
associated the two words together, nor was it until my invention was
completed, and had been successfully operated through ten miles, that
I, for the first time, learned, that the idea of an electric telegraph
had been conceived by another. To me it was original, and its total
dissimilarity from all the inventions and even suggestions of others,
may be thus accounted for. I had not the remotest hint from others,
till my whole invention was in successful operation. I employed myself
in the wakeful hours of the night, as well as in the tedious hours of
the day, _in devising the signs, adapting them to a single circuit of
wire_, and in _constructing machinery which should record the signs
upon paper_, for I thought of no plan short of a mode of recording.”
On the second of September, 1837, the author, with several others,
witnessed the first exhibition of this electric telegraph, and soon
after became a partner with the inventor. Immediate steps were taken
for constructing an instrument for the purpose of exhibiting its powers
before the members of Congress. This was done at the Speedwell Iron
Works, Morristown, N.J. and exhibited in operation with a circuit of
two miles. A few days after, it was again exhibited at the University
of the City of New York, for several days, to a large number of invited
ladies and gentlemen. The circuit at this time was increased to ten
miles. Immediately after this exhibition the instruments and ten
miles of wire were taken to Washington, and continued in operation
for several months, in the room of the Committee on Commerce at the
capitol. Its history and progress, after this period, may be gathered
from the preceding documents, printed by order of Congress.
_Schilling Electric Telegraph._
We make the following extract in relation to Schilling’s telegraph from
the Polytechnic Central Journal, Nos. 31, 32, 1838:
“Baron Schilling, of Caunstadt, a Russian Counsellor of State, likewise
occupied himself with telegraphs by electricity, (see Allgem Bauztg,
1837, No. 52, p. 440,) and had the merit of having presented a much
simpler contrivance, and of removing some of the difficulties of the
earlier plans. He reckoned many variations to the right, or left,
following in a certain order for a telegraphic sign, as, indeed, in
this manner, the needle was strongly varied, and only came to rest
gradually, after many repeated vibrations; he introduced a small rod
of platinum, with a scoop, which dipped into a vessel of quicksilver,
placed beneath the needle, and by the check given, changed the
vibration of the needle into sudden jerks. In order to apprise the
attendant of a telegraphic despatch, he loosed an alarm. How much of
this contrivance was Schilling’s own, or whether a portion of it was
not an imitation of Gauss and Weber, the author cannot decide, but that
Schilling had already experimented, probably with a more imperfect
apparatus, before the Emperor Alexander, and still later before Emperor
Nicholas, is affirmed by the documents quoted.”
From the report of the “Academy of Industry,” Paris, February, 1839, we
make the following extract, in relation to the same subject:
“At the end of the year, 1832, and in the beginning of 1833, M.
Le Baron de Schilling constructed, at St. Petersburg, an electric
telegraph, which consisted in a certain number of platinum wires,
insulated and united in a cord of silk, which put in action, by the aid
of a species of key, 36 magnetic needles, each of which were placed
vertically in the centre of a multiplier. M. de Schilling was the first
who adapted to this kind of apparatus, an ingenious mechanism, suitable
for sounding an alarm, which, when the needle turned at the beginning
of the correspondence, was set in play by the fall of a little ball of
lead, which the magnetic needle caused to fall. This telegraph of M. de
Schilling, was received with approbation by the Emperor, who desired it
established on a larger scale, but the death of the inventor postponed
the enterprise indefinitely.”
Dr. Steinheil in his article “upon telegraphic communication,”
published in the London Annals of Electricity, states, “that the
experiments instituted by Schilling, by the deflection of a single
needle, seems much better contrived, than the arrangement which Davy
has proposed, in which illuminated letters are shown by the removal of
screens placed in front of them.”
It would appear, that the French report is either incorrect, or that
M. de Schilling had two plans in contemplation. His plan as intimated
in the first and third extracts, is that of using a single needle in
the form of a galvanometer, by means of which he made his signals, for
instance, one deflection to the right might denote _e_; two _i_; three
_b_: one deflection to the left _t_; two _s_; three _v_. His code of
signals would then be devised in this manner:
rl A rrrl K llr U
rrr B lrrr L lll V
rll C lrl M rlrl W
rrl D lr N lrlr X
r E rlr O rllr Y
rrrr F llrr P rlrr Z
llll G lllr Q rrlr &
rlll H lrr R lrrl go on
rr I ll S lrll stop
rrll J l T llrl finish
rlrlr 1 lrlrl 6
rrlrr 2 rrllr 7
rlllr 3 rllrr 8
lrrrl 4 llrll 9
lrrll 5 llrrl 0
If, however, his plan was that ascribed to him, by the Academy of
Industry, of using 36 needles and 72 wires, it was exceedingly
complicated and expensive, and was similar to that invented by Mr.
Alexander, with the exception that Schilling used twice the number of
wires.
[27]_The Electro Magnetic Telegraph, of Counsellor Gauss and Professor
William Weber, invented at Göttingen, 1833._
The deflection of the magnetic bar, by means of the multiplier, through
the agency of the galvanic fluid, excited by the magneto electric
machine, is the basis of their plan.
[27] From the Polytechnic Central Journal, 1838, Nos. 31, 32.
[Illustration: FIG. 51.]
Figure 51 represents a side view of the apparatus, used at the
_receiving_ station: _a, a_ is a side view of the multiplier, composed
of 30,000 feet of wire, (almost 5½ miles,) upon a table, B: _n, s_ is
the magnetic bar, weighing 30 pounds, from which rises a vertical stem,
_o_, upon which is a rod at right angles, supporting a mirror, H, on
one end, and at the other a metallic ball, I, as a counteracting weight
to that of the mirror. The magnetic bar is suspended by a small wire,
fastened to the vertical stem, and at the top is wound round the spiral
of the screw, _i_, which turns in the standards, _h′_ and _h_, upon the
platform, A, and which is secured to the ceiling. In the standards,
_h′_, there is cut a female screw, of the same gradation as that upon
which the wire is wound. By this means, the magnetic bar may be raised
or let down, by turning the screw, without taking the bar from its
central position in the multiplier: _g_ is a screw for fastening the
spiral shaft, when properly adjusted. P and N are the two ends of the
wire of the multiplier. G is a stand for supporting the spy-glass, D,
and also the case, E, into which slides the scale, F. The mirror, H,
is at right angles with the magnetic bar, and presents its face to
the spy-glass, D, as also to the scale at E. It is so adjusted, that
the reflection of the scale at E, from the mirror, may be distinctly
seen by the spy-glass. If the magnetic bar turns either to the right
or left, the mirror must move with it, and if a person is observing
it through the spy-glass, the scale will appear to move at the same
time, thereby presenting to the eye of the observer another part of the
scale than that seen when the bar is not deflected. The figures on the
scale will show in what direction the bar has turned, and thus render
it distinct to the observer, the only apparent object of the mirror,
spy-glass and scale.
For the purpose of generating the galvanic fluid, they use the magneto
electric machine. Their plan, being unwieldy and difficult to operate,
is omitted, and in its stead, we introduce that form of it, invented
by Dr. Page, which has already been described in figures 45, 46 and
47. There is also required for the purpose of making the desired
deflections of the magnetic bar, a commutator, or pole changer, such
as we have described in figures 48, 49 and 50. Figure 51 represents
that portion of the apparatus at the _receiving_ station. The magneto
electric machine, and the pole changer, properly connected, are the
instruments of the _transmitting_ station. Two wires, or one wire and
the ground, form the circuit between these two stations. The machine
is put in operation by turning the crank, and the person sending the
intelligence is stationed at the commutator, and directs the current
through the extended wires to the multiplier of the receiving station,
so as to deflect the bar to the right or left, in any succession he may
choose, or suspend its action for any length of time.
“But in the apparatus for observation, the observer looks into the
spy-glass, and writes up the kind and results of the variations of the
magnetic needle. In order to have a control of the recorder, let there
be a good number of spy-glasses directed towards the same mirror, in
which observers may watch independently of each other. Suppose that
five variations of the magnetic needle signifies a letter. L denotes a
variation to the left, and R to the right. Then, might r r r r r denote
A; r r r r l denote B; r r r l r denote C; r r l r r denote D; and so
on. In the whole, we obtain, by the different arrangements of the five,
which are made with the two letters, R and L, 32 different telegraphic
signs, which may answer for letters and numbers, and of which we can
select those where the most changes are introduced between _r_ and _l_,
as the most common letters, in order, in the best possible manner, to
notice the constant variations of the magnetic needle.”
The following would be the alphabetical signs, as arranged from the
above directions:
A r r r r r | I or Y l l r l l | R r r r l l
B r r r r l | K l r r r l | S or Z r r l r l
C r r r l r | L r l r r r | T l l r l r
D r r l r r | M r r l l l | U r l l l r
E r l r l r | N l l l l l | V l r r l l
F l r r r r | O l r l l l | W l l l l r
G or J l r l r r | P l r l r l |
H r l r r l | Q l l r r r |
_Numerals._
1 r l l l l | 6 r l l r r
2 r r l l r | 7 l l l r l
3 r l r l l | 8 l l r r l
4 r l l r l | 9 l r r l r
5 l l l r r | 0 l r l l r
It will be seen, that, by representing the letters and numerals with
these variously combined deflections of the needle, words and sentences
may be transmitted. At the end of each letter there is a suspension of
the action of the bar for a short time, and at the end of a word, a
still longer pause. This plan of an electric telegraph was tried for
a distance of one mile and a quarter, in Göttingen. Of its further
success, we are not informed.
_Experiment of Messrs. Taquin & Ettieyhausen._[28]
“Messrs. Taquin and Ettieyhausen made experiments with a telegraphic
line over two streets in Vienna, 1836. The wires passed through the air
and under the ground of the Botanic garden.”
No other account appears to have been given of their experiments than
that quoted above.
[28] From the Polytechnic Central Journal, 1838.
_Electro Magnetic Printing Telegraph, invented by Alfred Vail,
September, 1837._
Soon after my connection with Professor Morse as copartner, and at the
time I was constructing an instrument for exhibiting the advantages of
his telegraph to a committee of Congress, it occurred to me, that a
plan might be devised, by means of which the letters of the alphabet
could be employed in recording telegraphic messages. I immediately gave
it my attention, and produced the following plan:
Figure 52 represents a front and side view of the instrument.
Figure 55 is a top view.
Figure 56 is a back view.
The same parts are represented by the same letters in the three views.
In figure 52, Q, Q is the platform upon which the whole instrument is
placed. M and M are wooden blocks supporting parts of the instrument, K
is the helix of the soft iron bar, H, passing through its centre, and
there is another coil and bar directly behind this; the two making the
electro magnet. G is its armature, fastened to the lever, F, F, which
has its axis at I, (seen in figure 55, at X, X.) R is a brass standard
for supporting the lever, F, upon its axis, by means of two pivot
screws: _a_ and _a_ are two screws passing vertically, through the
standard, R, for limiting the motion of the lever, F, F. J is a spiral
spring, at its upper end, fastened to the lever, F, and at its lower
end passes through the screw, L, by which it is adjusted, so as to
withdraw the armature from the magnet, after it has ceased to attract,
and for other purposes, hereafter to be explained. N and O is a brass
frame, containing the type wheel, B′, and the pulley, E and U. P and
P represent the edge of a narrow strip of paper, passing between the
type wheel and pulley, E. D is the printer, which, at the bottom, forms
a joint with the end of the lever F and _r_. B represents twenty-four
metallic pins, or springs, projecting at right angles from the side of
the type wheel; each pin corresponding in its distance from the centre
of the type wheel, to its respective hole, represented by dots upon,
the index, C; so that if the pin is put in any one of the holes, the
type wheel, in its revolution, will bring its corresponding pin in
contact with it.
[Illustration: FIG. 52.]
There are 24 holes corresponding to the following letters of the
alphabet. A, B, C, D, E, F, G, H, I, K, L, M, N, O, P, Q, R, S, T,
U, V, W, X, and the types are lettered accordingly. The cog wheels,
T and S, are a part of the train of the clock. The lever, F, F, has
two motions, one up and another down, and both are employed by an
attachment at the end of the lever, _r_, and in the following manner:
figures 53 and 54 represent a front and end view of the roller, E, and
printer, D, (figure 52,) enlarged. D is the printer, figure 53, of the
form shown by D, (figure 54.) E is the roller over which the paper, P,
is carried. A is the front of the type having ears, _h, h_, projecting
from each side. Through the sides of the printer, D, D, a rod, U,
passes, in order to give more firmness to the frame. The rod projects
a little on each side of the frame at J, J. These projections slide in
a long groove in the frames, N and O, figure 52, by which the printer
is kept in its position, and allowed freely to move up and down. It
will be observed that the upper parts of the frame, D, D, extends over
the top of the roller, E, and nearly touch each other, but are so far
separated, as to let the type, A, of the type wheel, in its revolution,
freely pass between them: _d′, d′_, are the sides of the joint, which
are connected with the lever, F, fig. 52. From the construction of this
part, it will appear that if the printer, D, is brought down by the
action of the magnet upon the lever, the two projections, _k, k_, will
come in contact with the ears, _h, h_, and bring the type in contact
with the paper upon the roller, E, and produce an impression. In figure
54 is shown a ratchet wheel, _i_, on the end of the roller, E, a catch,
_e_, and spring, _c′_, adapted to the ratchet. Upon the release of the
lever, F, fig. 52, the spring, J, will carry down the lever on that
side of its axis, and up at _r_, which will cause the roller, E, to
turn, and consequently the paper, P, to advance so much by the action
of the catch, _e_, upon the ratchet wheel, as will be sufficient for
printing the next letter.
[Illustration: FIG. 53. FIG. 54.]
Figure 55 represents a top view of the machine. S is the barrel upon
which is wound a cord, sustaining a weight which drives the clock
train, and upon the same shaft with it is a cog wheel driving the
pinion, _m_, on the shaft, T; and on the same shaft, T, is another cog
wheel, driving the pinion, _n_, of the type wheel shaft, I′. K and K,
are the helices of the large magnet, of which H and H are the soft iron
arms. M, M, M, M, are the blocks which support the instrument. F and F
is the lever, _a_ and _a_ its adjusting screws; _x′_ and _x′_ its axis;
_k_ and _k_ are the two upper coils of the two electro magnets at the
back part of the instrument for purposes hereafter to be described;
_x_ is the wire soldered to the plate buried in the ground; _p_ is the
wire proceeding to the battery; _c_ is the connecting wire of the two
electro magnets, _k_ and _k_; w is the support of the pendulum; _v_ is
the escapement wheel; A is the type wheel; D and D is the printer, and
B the roller over which the paper, P, is carried.
[Illustration: FIG. 55.]
[Illustration: FIG. 56.]
Figure 56 represents a back view of the instrument; _k_, _k_ and _k_,
_k_ are the coils of two electro magnets, surrounding the soft iron
bars, _d_, _d_ and _d, d_; _b_ and _b_ are the flat bars through which
_d, d_ and _d, d_ pass, and are fastened together by the screw nuts
_c, c_ and _c, c_. The right hand electro magnet is fastened to the
blocks, M and M, by the support, _f_ and _f_; from which proceeds a
bolt passing between the coils, _k_ and _k_, and the block, _h_, with
a thumb-nut upon it, by which the whole is permanently secured. In
the same manner the left hand magnet is secured to the block, M. R′
is the outside portion of the brass frame containing the clock work.
W is a standard fastened to R′, for supporting the pendulum, Y. X,
Y, and _l_ are parts common to a chronometer for measuring the time,
viz. the escapement and pendulum. The escapement wheel has 24 teeth,
corresponding in number with the type on the wheel, and such is the
arrangement of the parts, that when the pendulum is upon the point of
return, either on the right or left hand, a type is directly over the
paper, and the armature, _g_, is near the face of one or the other of
the magnets; so that, if an impression is to be made with the type,
thus brought to the paper, the pendulum, Y, is ready to be held by the
magnet at the same time from making another swing until the type has
performed its office, which will be hereafter explained.
A shows the type as they are arranged on the wheel. The types are
square, and move freely in a groove, cut out of the brass type wheel.
At 1 and 2 are seen flat brass rings, which are screwed to the wheel,
and over the types, confining them to their proper places. Z is a
spiral spring, of which there is one to each type, by means of which
the type is brought back to its former position, after it is released
by the printer. Through each type there is a pin, against which the
inner end of the spiral spring rests. The outer end of the spring
rests against the circular plate. W represents the wire from the upper
helix, soldered to the metallic frame, R′. The two helices of the left
hand magnet are joined together, and from the bottom helix the wire
proceeds to the lower coil of the right hand magnet. These two helices
are likewise connected, and the wire leaves the upper coil at _x_. Thus
the wire is continuous from _w_ to _x_. From _x_, the wire is continued
to a copper plate, buried in the earth. The frame, R′, being brass,
the arbor of the type wheel, and the wheel itself, and each being in
metallic contact, they answer as a continuous conductor with the wire,
_w_, for the galvanic fluid.
The index, _c_, figure 52, is insulated from the frame, N, being made
of ivory. There is inserted in the ivory, a metal plate, containing the
holes, to which is soldered a wire, _q_, connected with the back coil,
K. The two helices being connected, the wire of the front helix comes
off at _p_, and from thence is connected with one pole of the battery;
from the other pole, it is extended to the distant station, and is
there connected with a similar instrument. It will be observed, that
the circuit is continuous, except between the type wheel and the metal
plate in the ivory. When neither station is at work, the batteries of
both are thrown out, and their circuits, retaining in them the magnets
of both stations, are closed. For this purpose, there is an instrument
at each station, resembling in some respects the pole changer, figures
48, 49 and 50. If one of the stations wish to transmit by reversing his
circuit instruments, the battery is instantly brought into the circuit.
Through the agency of the clock work and weight, and the pendulum,
both instruments are vibrating together, and their type wheels are
so adjusted, that when _A type_, of one station, is vertical, the _A
type_, of the other station, is also vertical. Now, suppose one station
wishes to transmit to the other, the word _Boston_, for example: he
first brings his battery in the circuit, then places a metallic pin in
the hole of his index, C, marked for the letter B. When the type wheel
shall have brought round the pin, corresponding to the type, B, on the
wheel, its pin will come in contact with the inserted pin of the index,
and instantly the circuit is established. The fluid, passing through
the coils of the magnets, on each side of the pendulum, will hold it,
and also passing through the coils, K, will bring down the lever, F, F,
and with it, the printer, D, which, as heretofore described, in figures
53 and 54, will bring the type, with considerable force, against the
paper. The instant the two pins have come in contact with the moving
pin, it is taken out and put in the hole, O, when the same operation is
performed, and in like manner for the remaining letters of the word.
The pin can be so arranged, as to be thrown out the instant a complete
contact is made.
The rapidity of this printing process would be as follows: Suppose the
pendulum makes two vibrations in a second; that is, it goes from right
to left in half a second, and returns in half a second. Since, then, a
single letter is brought to the _vertical position_, ready to be used
if needed, at the end of each vibration, it is clear, that two letters
are brought to the vertical position every second, or 120, every
minute. This is not, however, the actual rate of printing; for, in the
word _Boston_, the type wheel, after B is printed upon the paper, must
make so much of a revolution as will bring the letter O to the paper.
This will require 12 vibrations of the pendulum; S will require 4; T,
1; O, 18, and N, 22; equal to 57, to which add 6, the time required
to print each letter, will make it 63. This, divided by 2, gives 31½
seconds, the time necessary to print 6 letters. If we now take an
ordinary sentence, and estimate, in the same manner, the time required
to print it at the distant station, we shall be able to find what
number of letters it can print per minute.
“There will be a declaration of war in a few days, by this government,
against the United States. Orders have just been received to have all
the public archives removed to Jalapa, which is sixty miles in the
interior, for safe keeping.”
Here are 184 letters, and would require 2266 vibrations, to which add
184, the number of letters would give 2450 half seconds, equal to
1225 seconds, the time required for printing the message; or over 20
minutes; the rate being six and two-thirds seconds for each letter.
If, however, a vocabulary is used, with the words numbered, and
instead of using the 26 letters of the alphabet on the type wheel, we
substitute the 10 numerals, in their place, we reduce the time required
for a revolution of the wheel, and it is clear that this same message
may be transmitted in much less time.
The following numbers represent the words of the same message, in
the numbered vocabulary: 48687, 54717, 4165, 1, 12185, 34162, 54078,
25393, 1, 18952, 11934, 6177, 48766, 21950, 1106, 48652, 51779, 46532,
34475, 22991, 28536, 4321, 40254, 49085, 22991, 1391, 48652, 39087,
3845, 41278, 49085, 28536, 54536, 28668, 45008, 31634, 25393, 48652,
27326, 19865, 42813, 28592. Here are 42 numbers, and 196 figures. To
196 add 42, the spaces required, and we have 238 impressions to make,
to write the sentence thus represented. By calculation, we find there
is required, in order to bring each numeral and space in its proper
succession, to the vertical position, 1624 vibrations of the pendulum,
which, at the rate of two to the second, gives the time required to
transmit the message at 812 seconds, or nearly 13 minutes, being at the
rate of 18⅓ letters per minute.[29]
If, however, the vibrations of the pendulum are increased at the rate
of 4 in a second, then the time required for the transmission of the
message would be almost 7 minutes, and at the rate of 36⅔ letters per
minute.[30] If it be increased to 6 vibrations per second, then the
time would be 4½ minutes, and at the rate of 55 impressions per minute.
[29] A day’s work of a fair compositor in setting up type is 6,000 ems,
equivalent to 12,000 pieces, in ten hours, or 20 pieces per minute. A
very quick and expert compositor may set up 10,000 in the same time,
equal to 20,000 pieces, or 33⅓ pieces per minute. One em is equivalent
to about two pieces.
[30] The author has recently devised a new plan for printing with type,
in which the pendulum movement is dispensed with, and the motion of
the type wheel is dependent upon the control and government of certain
apparatus at the transmitting station. This controlling part is capable
of giving to the type wheel a most rapid movement, and from an estimate
made from some actual tests, the number of letters capable of being
printed, are increased much beyond the former plan, taking the message
already used as an example. Still he considers it inferior to that
mode, now adopted by Professor Morse.
The modes of using the English letter for recording telegraphic
messages are various, and they may be classed, as, First, Those which
are rapid in transmission; expensive in construction, and complicated
in machinery. Second, The less rapid in transmission; economical
in construction, and simple in its machinery. Third, The slow in
transmission; less expensive than the first class in construction; but
complicated in its machinery.
To the _first_ class, belong those using 26 types; one for each of
the letters of the alphabet, and 13 extended wires, from station to
station, with more or less battery. These types are arranged in a row,
directly over the paper which receives the impression, and consequently
require a strip of paper some 4 or 5 inches broad. Each type is
furnished with an electro magnet and lever, answering as a hammer to
bring down the types upon the paper. As the types are arranged in a
straight line, they would present the following order:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
- - - - - - - P R -
- - - - I - N - - T
- - - - I - N - - -
- - G - - - - T
- E - - L - -
- E G - - R
A - - P
H
Here we have the style of this kind of printing. By spelling the
letters on the first line, then on the second, and so on, the words
“Printing Telegraph” can be made out. Those letters which follow each
other in the word, and also follow each other in the alphabet, are
placed upon the same line, but when a letter occurs preceding the last,
a new line must be taken, otherwise the word cannot be read. It will
appear, that in this mode, sometimes two or three, or four letters,
may be printed at one and the same instant, where they succeed each
other in alphabetical order. This plan is extremely rapid for _one
instrument_, but extremely slow for _thirteen wires_.
Supposing two such instruments are used upon a line of 40 miles, and
suppose the wire to cost per mile, fifty dollars. The expense for wire
alone would be $26,000. There are other expenses which we will omit
in this, as well as those plans which will be described hereafter.
Let it be assumed, in order to make equal comparison throughout, that
the number of successive motions of the type lever, in these various
plans about to be given, are 4 to a second. But as this instrument
may make, with two or more of its levers, two or more impressions per
minute, let it be 8 instead of 4 per second. It will then be capable
of transmitting 480 letters per minute. With all this, there are many
disadvantages, which will be developed as we proceed.
Under the same class, there is another plan, using the 26 types upon
the ends of as many levers, each lever employing the electro magnet,
and the line consisting of 13 wires. In this arrangement the types
are made to strike in any succession required by the message, at the
_same point_ upon the paper, _falling back_ and resuming their first
position, after having printed their letter, in order to allow the next
type to occupy the same point previously occupied by the other. The
printing of this plan will appear on paper as ordinary printing. Thus,
PRINTING TELEGRAPH. If we suppose that 4 hammers, carrying type, can
strike the _same point_ in a second, and each resume their original
position in succession, thus passing each other without collision, it
may print at the rate of 240 letters per minute.[31] The instrument
would be a complicated one and subject to derangement.
[31] Mr. Vail invented an instrument with this arrangement 16 years
ago, for the purpose of printing speeches as fast as delivered.
To the _second_ class, belong all those which print in letters of an
hieroglyphical character. The _first_ plan is that employing one wire
and one motion. Under this head, is that of Prof. Morse’s. He employs
but one wire and one electro magnet for printing, which has but one
motion. Suppose this to be capable of operating with the same speed as
the preceding, viz. four motions per second. The telegraphic alphabet
as adopted by Prof. Morse require for each letter the following
number of motions of the type or pen lever, as lines require time in
proportion to their length, they are so estimated: A 3, B 5, C 4, D 4,
E 1, F 4, G 5, H 4, I 2, J 6, K 5, L 5, M 4, N 3, O 3, P 5, Q 5, R 4,
S 3, T 2, U 4, V 5, W 5, X 5, Y 5, Z 5.
If we take the _standard number_ of types for each letter constituting
it printer’s case, considering Z as 2, we shall have A 85, B 16, C 30,
D 44, E 120, F 25, G 17, H 64, I 80, J 4, K 8, L 40, M 30, N 80, O 80,
P 17, Q 5, R 62, S 80, T 90, U 34, V 12, W 20, X 4, Y 20, Z 2. The
whole number of letters are 1177. The number of motions required to
transmit them would be 3420, to which add, one motion for the time
required to space a single letter, and we have 4597 motions, made in
printing 1177 letters which will make the average number of motions to
each letter 3¹⁰⁶⁶/₁₁₇₇, nearly 4. Let it be 60 per minute. Expense for
one wire of 40 miles, $2000.
_Second plan_, is that where two wires are used, two magnets, two type
levers, and the telegraphic characters, such as are represented in
table 1, page 30. The first three letters require three motions each;
the next 16, require 2 each, and the last 7, require 3 each. Taking the
1177 letters, the motions required to transmit them in the characters
of this alphabet, would be, 2195 + 1177 for spaces and would equal
3372, which divided by 1177, would give the average number of motions
at 2¹⁰¹⁸/₁₁₇₇ for each letter, nearly three or 80 per minute. Cost of
wire $4000.
_Third plan_, is that using three wires, three magnets, three type
levers and the telegraphic characters represented in table second, page
30. The seven first would require one motion each, and the remainder
two each. Taking 1177 letters, the motions required to transmit them,
would be 1917 + 1177 for spaces, and would equal 3094 motions, which,
divided by 1177, would give the average number of motions 2⁷⁴⁰/₁₁₇₇
for each letter, nearly 2⅔, or 85 letters per minute. Cost of wire
$6000.
_Fourth plan_ consists in using four wires, four electro magnets,
four type levers, and the telegraphic characters of the third table.
The first sixteen letters require the time of but one motion each;
the remainder, two each. Using 1177 letters, the motions required
to transmit them would be 1506 + 1177 for spaces, and would equal
2683, which divided by 1177, would give the average number of motions
2³²⁹/₁₁₇₇ for each letter, nearly 2⅓, or 103 letters per minute. Cost
of wire $8000.
_Fifth plan_, is that of using five wires, five electro magnets,
five type levers, and the telegraphic characters of the 4th table.
The characters would require one motion each, equal to 1177 + 1177
for spaces, and would equal 2354, which, divided by 1177, would give
the average number of motions, 2 for each letter, or 120 letters per
minute. Cost of wire $10,000.
We now come to the _third_ class, in which 26 types are used, arranged
upon the periphery of a wheel, in alphabetical order, and require to be
brought to one certain point, where the paper is ready to receive the
impression of the type, by another arrangement, distinct from the type
wheel and its machinery. Of this plan, is that which has been already
described in figures 52, 55 and 56. The estimate is there carried out,
at 4 motions per second, gives 36⅔ letters per minute. Cost of wire
$2000.
The following table will show the comparative value of these various
methods:
Letters per Cost. Number of On Morse’s No.
minute. wires. plan.
1st Class. { 1st plan, 480 $26,000 13 780 1
{ 2d “ 240 26,000 13 780 2
2d Class. { 1st plan, 60 2,000 1 60 3
{ 2d “ 80 4,000 2 120 4
{ 3d “ 85 6,000 3 180 5
{ 4th “ 103 8,000 4 240 6
{ 5th “ 120 10,000 5 300 7
3d Class. 1st plan, 37 2,000 1 60 8
We find by comparison that Morse’s plan, No. 3, of using a single wire,
with a single instrument, produces 60 characters per minute; while
No. 1, with 13 wires, and one instrument, produces 480 characters per
minute. Let, however, the 13 wires be multiplied by 60, (the number of
characters which a single instrument of the plan, No. 3, can transmit,)
the number of characters which 13 wires, with 13 instruments would then
produce, are 780 or 300 more than the _single instrument_, with 13
_wires_. The same comparisons may be made with the other plans, and it
will be found that no advantage can be gained by their adoption.
All electro magnetic telegraphs require as their basis, the adoption of
the _electro magnet_, where recording the intelligence is an object,
and it would seem, must be applied in a manner equivalent to that mode
adopted by Prof. Morse; that is, the application of the armature to a
lever, and its single movement produced by closing and breaking the
circuit. It is, therefore, safe to assume, that whatever improvement in
one plan may be made to increase the rapidity of the movements of those
parts of the telegraph which belong to the electro magnet, are equally
applicable to any other plan, provided too much complication, already
existing, does not counteract and defeat the improvement.
Some plans, however, use an extra agent besides the electro magnet,
which is employed for measuring the time of the revolution of the
type wheel, and the electro magnet is only called in, occasionally,
to make the impression. In such plans the rapidity of communication
demands the combined action, alternately, of both magnets. This, of
course, increases the complication, and must certainly be considered
a departure from other more simple arrangements. Whatever will reduce
the inertia of mechanical movements and bring them to act with an
approximate velocity, at least of the fluid itself, will increase the
rapidity of transmission. The more the instrument is encumbered with
the sluggish movements of material bodies, the less rapid, inevitably,
must be its operation, even where several co-operating agents are
assisting, in their respective spheres, to increase the rapidity of
the motion. Such is the case with the several kinds of letter printing
telegraphs: very weighty bodies, comparatively speaking, are set in
motion, stopped, again set in motion, and along with this irregular
motion, other parts perform their functions. There must be a courtesy
observed among themselves, or matters do not move on as harmoniously as
could be desired. This is not always the case, especially where time is
the great question at issue.
All printing telegraphs which use type, arranged upon the periphery of
a wheel, must have, of necessity, these several movements, viz. the
irregular revolution of the type wheel, stopping and starting at every
division or letter; the movement of the machinery, called the printer;
the irregular movement of the paper, at intervals, to accommodate
itself to the letter to be printed; the movement of the inking
apparatus, or what is not an improvement in cleanliness, paper of the
character used by the manifold letter writer. So many moving parts, are
so many impeding causes to increased rapidity, and are, to all intents
and purposes, a _complication_.
The requirements of a perfect instrument are: economy of construction,
simplicity of arrangement, and mechanical movements, and rapidity of
transmission. To use one wire is to reduce it to the lowest, possible
economy. If there is but one movement, and that has all the advantages
which accuracy of construction, simplicity of arrangement and
lightness, can bestow upon it, we might justly infer that it appeared
reduced to its simplest form.
The instrument employed by Professor Morse has but a single movement,
and that motion of a vibratory character; is light and susceptible of
the most delicate structure, by which rapidity is insured; the paper
is continuous in its movement, and requires no aid from the magnet to
carry it.
The only object that can be obtained by using the English letters,
instead of the telegraphic letters, is, that the one is in common use,
the other is not. The one is as easily read as the other, the advantage
then is fanciful and is only to be indulged in at the expense of time,
and complication of machinery, increasing the expense, and producing
their inevitable accompaniments, liability of derangement, care of
attendance, and loss of time.
_Wheatstone’s Electric Needle Telegraph, invented in 1837._
The following description is taken from a pamphlet, published by T.
S. Hodson, 15 Cross street, Hallon Garden, London, 1839, for the
proprietors. It is unnecessary to copy the legal and technical wordy
mass of the specification, embracing fifty-nine pages of closely
printed matter of octavo size. A full description will be given,
with the accompanying figures, so as to enable the reader fully to
comprehend Mr. Wheatstone’s plan.
His arrangement requires the service of five galvanometers, in every
respect similarly constructed as that described by the figures 27,
28 and 29. Figure 57 is a representation of his dial, which is
also a covering to the case containing, in the interior, the five
galvanometers and their wires, (shown at the opening in the dial
board,) and numbered, 1, 1; 2, 2; 3, 3; 4, 4, and 5, 5. The coils of
the multipliers are secured with their needles to the case, having
each exterior needle projecting beyond the dial, so as to be exposed
to view. Of the wires from the coils, five are represented as passing
out of the side of the case, on the left hand, and are numbered 1,
2, 3, 4 and 5. The other five wires pass out on the right hand, and
are numbered in the same manner. The wires of the same number as
the galvanometer, are those which belong to it, and are continuous.
Thus the wire 1, on the left hand, proceeds to the first coil of
galvanometer 1, then to the second coil, and then coming off, passes
out of the case, and is numbered 1, on the right hand. So of the other
wires, thus numbered. The dial has permanently marked upon it, at
proper distances and angles, twenty of the letters of the alphabet,
viz. A, B, D, E, F, G, H, I, K, L, M, N, O, P, R, S, T, V, W, Y. On
the margin of the lower half of the dial are marked the numerals, 1,
2, 3, 4, 5, 6, 7, 8, 9 and 0. The letters C, J, Q, U, X, Z, are not
represented on the dial, unless some six of those already there are
made to sustain two characters each, of which the specification is
silent. Each needle has two motions; one to the right, and the other to
the left. For the designation of any of the _letters_, the deflection
of two needles are required, but for the _numerals_, one needle only.
The letter intended to be noted by the observer, is designated, in the
operation of the telegraph, by the _joint deflection_ of two needles,
pointing by their convergence to the letter. For example, the needles,
1 and 4, cut each other, by the lines of their joint deflection, at
the letter V, on the dial, which is the letter intended to be observed
at the receiving station. In the same manner any other letter upon
the dial may be selected for observation. Suppose the first needle
to be vertical, as the needles 2, 3 and 5, then needle 4 being only
deflected, points to the numeral 4, as the number designed.
[Illustration: FIG. 57.]
We will now proceed to describe the arrangement of the springs and
buttons upon the platform, C, C, figure 58, (representing a top
view,) by the operation of which, any two needles may be deflected to
designate a letter, or one needle to designate a numeral.
[Illustration: FIG. 58.]
The numbers 6, 1, 2, 3, 4 and 5, represent keys of thin brass, and
elastic, and are each fastened to a wooden support, D, D, by means
of two screws. These keys are continued under and project beyond,
the brass bar, L and L, which is supported by two standards, R
and R. Whenever these keys are not pressed upon, they are each in
_metallic contact_ with the _bar_, R and R. The numbers 7, 8, 9,
10, &c. represent ivory buttons with a metallic stem beneath them,
passing through a hole in the spring, or key, and on the lower side
of the spring the stem is enlarged, so as to form a kind of hammer,
designed to make a metallic contact with the two brass bars, beneath
the springs, and represented as supported by the standards, N and N
and P and P. Each of the buttons have a small wire spiral spring, to
which they are fastened, and the small spring is itself fastened to the
larger spring. O represents the galvanic battery, with its poles in
connection with the two metallic bars, N and P.
Figure 59 represents a side view of the key arrangement. F is the
platform. E the wooden support of the six keys. H is the larger spring,
or key, secured to the support by screws, _h_. The spring is observed
to project beyond the metallic cross bar, L, after passing beneath it.
R is the support of the cross bar, L. N and O are two of the ivory
buttons, upon their spiral springs, _a_ and _c_. Below the button, O,
is a shoulder, formed at _i_, upon the stem which passes through the
spring, H, and another shoulder is formed by the hammer, _u_, below
the spring. It will be observed, that two buttons of the same key are
never used at the same time. If the button, O, is to be pressed down,
the weaker spring, _c_, will permit it to descend until the upper
shoulder comes in contact with the larger spring, H, when more pressure
is applied, and that spring is brought down, breaking its contact with
the metallic cross bar, L, until the hammer, _u_, comes in contact
with the metallic plate, _n_, upon the support, K, and as the plate,
_n_, is connected with N pole of the battery, the connection is formed
with it. It will, however, be noticed, that the button, N, not being
pressed upon, _will not_, (though it descends with the larger spring,)
be brought in contact with the other plate upon the support, J, and
connected with the positive pole of the battery. To the end of each
spring, a wire, S, is soldered, the purpose of which will be shown
hereafter.
[Illustration: FIG. 59.]
[Illustration: FIG. 60.]
Figure 60 represents an end view of the key arrangement; _a_, _b_, _c_,
_d_, _e_, _f_, are the buttons, M and M the metallic cross bar, beneath
which are seen the ends of the six larger springs, 6, 1, 2, 3, 4 and
5. R and R are the supports of the bar, M and M. G is the platform. W
is the support of the metallic plates, with which the hammers of the
little keys, or buttons, come in contact. S the wire leading to the
battery.
Having shown the several parts of Mr. Wheatstone’s plan, we will
proceed to describe the arrangement of two termini, as prepared for
transmitting intelligence. Figure 61 represents the arrangement of one
station, which we may suppose to be PADDINGTON. Figure 62 represents
the plan of the other station, which we will suppose to be SLOUGH. The
distance between these two places is eighteen miles.
In figure 61, it will be seen, that a wire is soldered to the end of
each of the springs 6, 1, 2, 3, 4 and 5, and are respectively connected
with the five wires of the dial, and the common communicating wire,
number 6, which does not pass through the dial, nor is connected with
any of the galvanometers. On the right hand side of the dial, the wires
are extended until they are shown as broken. From this point to the
opposite one, figure 62, where the wires appear also as interrupted,
we may suppose 18 miles to intervene. The wires here proceed to the
dial of the Slough station, making their proper connections with their
respective galvanometers, and from thence are continued and soldered
to their springs of the key arrangement, with the exception of wire,
number 6, which passes direct to the key, 6, without going through the
dial case. In both figures, is represented the battery, O, consisting
of six cups. The wire from one pole of the battery is connected with
the N metallic plate, the other wire with the P metallic plate. While
none of the buttons are pressed down, the battery is _not_ in action,
and it will also be observed that the circuits are all _complete_. The
action of the keys, then, is this, by a single operation to break the
circuit formed with the cross bar, L, L, and, at the same time, bring
_into_ the circuit, the battery, O.
The following numbers, representing the buttons, are those necessary
to be pressed down, in order to signal the letters and numerals on the
dial:
_Letters._
For A, buttons 10 and 17. | For M, buttons 9 and 12.
“ B, “ 10 “ 15. | “ N, “ 11 “ 14.
“ D, “ 12 “ 17. | “ O, “ 13 “ 16.
“ E, “ 10 “ 13. | “ P, “ 15 “ 18.
“ F, “ 12 “ 15. | “ R, “ 9 “ 14.
“ G, “ 14 “ 17. | “ S, “ 11 “ 16.
“ H, “ 10 “ 11. | “ T, “ 13 “ 18.
“ I, “ 12 “ 13. | “ V, “ 9 “ 16.
“ K, “ 14 “ 15. | “ W, “ 11 “ 18.
“ L, “ 16 “ 17. | “ Y, “ 9 “ 18.
_Numerals._
For 1, buttons 7 and 10. | For 6, buttons 8 and 9.
“ 2, “ 7 “ 12. | “ 7, “ 8 “ 11.
“ 3, “ 7 “ 14. | “ 8, “ 8 “ 13.
“ 4, “ 7 “ 16. | “ 9, “ 8 “ 15.
“ 5, “ 7 “ 18. | “ 0, “ 8 “ 17.
[Illustration: FIG. 61. PADDINGTON.]
[Illustration: FIG. 62. SLOUGH.]
The direction of the current, when the letter V is to be signalled, is
this: pressing down the buttons, 9 and 16, at the Paddington station,
the fluid leaves the battery, O, along the wire to the cross bar, P;
then to the hammer of the button, 16; then to the spring, 4; then along
wire, 4, to the galvanometer, 4, and through it, deflecting the lower
half of the needle to the left; then along the extended wire, 4, to the
dial, and galvanometer, 4, of the Slough station, deflecting the lower
half of that needle to the left; then to wire, 4, leaving the dial, to
key, 4; then to the cross bar, L and L; and along the cross bar to key,
1; then to wire, 1; then to galvanometer, 1; and through it, deflecting
the lower half of the needle to the right; thence it proceeds along the
extended wire, 1, to the Paddington station; entering the dial to the
galvanometer, 1, deflecting the lower half of the needle to the right;
then along wire, 1, to the key, 1; then to button, 9; then to the cross
bar, N, beneath; and then to the negative pole of the battery, O. It
will be observed, that the needles of both stations, thus deflected,
point to the same letter, V. In Mr. Wheatstone’s arrangement, but one
person can transmit at the same time, although he uses six extended
wires. One must wait while the other is transmitting.
If a numeral is to be signalled, it is obvious, that but one
galvanometer is needed. We will, therefore, suppose that the needle, 1,
is vertical.
Let the buttons, 7 and 16, be pressed down, at the Paddington station.
The current then leaves the positive pole of the battery, O, to the
cross bar, P; then to the key, 4; then along wire, 4, to galvanometer,
4, deflecting the lower half of the needle to the left; from thence to
the Slough station to galvanometer, 4, deflecting the lower half of the
needle to the left; then to wire, 4; then to key, 4; then to the cross
bar, L and L, and along it to key, 6; then to wire, 6, and along the
extended wire to the Paddington station, to key, 6; then to the cross
bar beneath the button, 7; then to the negative pole of the battery, O.
The needles, 4 and 4, of both stations, are simultaneously deflected,
so as to point to the figure, 4, on the margin of the dial.
In this manner the circuits required for each letter and numeral may
be traced out. Now, suppose the message to be sent from the Paddington
station to the Slough station, is this, “WE HAVE MET THE ENEMY AND
THEY ARE OURS.” The operator at Paddington presses down the buttons,
11 and 18, for signalizing upon the dial of the Slough station, the
letter W. The operator there, who is supposed to be constantly on the
watch, observes the two needles pointing at W. He writes it down, or
calls it out aloud, to another, who records it, taking, according to a
calculation given in a recent account, two seconds at least for each
signal. Then the buttons, 10 and 13, are pressed down, and the needles
are observed to point at E; and so for the remaining letters of the
sentence, U excepted, which has no letter on the dial.
The peculiarity of Mr. Wheatstone’s plan, is, the employment of six
wires for one _independent_ line of communication. The use of five
galvanometers, with their needles, by the deflection of which, 30
letters and numerals are pointed out. The messages are not recorded by
the instrument itself, but it is necessary that a person be constantly
observing the successive movements of the needles, and note them down
as they point to the signal. This plan was invented in 1837, and as
Prof. Wheatstone took out letters-patent in the United States, in 1840,
for this arrangement, it is a fair inference, that at that time, this
was his simplest and most perfect method.
_Steinheil’s Electric Telegraph._
Description of the magneto electrical telegraph, erected between
Munich and Bogenhausen, in 1837, by Dr. Steinheil,[32] Professor of
Mathematics and Natural Philosophy at the University of Munich, taken
from the Annals of Electricity, Magnetism and Chemistry, conducted by
William Sturgeon, London, April, 1839.
[32] Steinheil in the account he gives of his own telegraph, says,
“Gauss mentions a communication from Humboldt, according to which
Belancourt, in 1798, established a communication between Madrid and
Aranjuez, a distance of 26 miles, by means of a wire, through which a
Leyden jar used to be discharged, which was intended to be used as a
telegraphic signal.”
[Illustration: FIG. 63.]
A, A represents a vertical section, through the centre of the coil of
copper wire. C is the interior brass frame, round which the wire is
wound. B and B are the sides of the frame; I, I, I, I are four brass
tubes, soldered to the interior brass frame, and passing through the
centre of the coil to its exterior, with a screw cut in the end of
each; D and D are two permanent magnets movable on their axis, _a_ and
_b_. These spindles, _a_ and _b_, on each side of the magnets, pass
up the hollow of the tubes, and having their ends pointed, enter the
centre cavity of the four thumb screws, J, J, J, J, by which they are
supported, and delicately adjusted, so as to move easily and freely. L
and L are the ends of the wire leaving the coil. H and K are two ink
holders, attached to the magnets, which will be explained hereafter.
[Illustration: FIG. 64.]
Figure 64 represents a horizontal section of the coil, and magnets
D′ and D′, as above described, together with the other arrangements
of the instrument for receiving intelligence. The magnetic bars are
so situated in the frame of the multiplier, that the north pole, N′,
of the one, is presented to the south pole, S′, of the other. To the
ends which are thus presented to each other, but which, owing to the
influence they mutually exert, cannot well be brought nearer, there are
screwed on two slight brass arms, supporting little cups, H′ and K′.
These little cups, which are meant to be filled with printing ink, are
provided with extremely fine perforated beaks, that are rounded off in
front. When printing ink is put into them, it insinuates itself into
the tube of their beaks, owing to capillary attraction; and without
running out, forms at their apertures, a projection of a semiglobular
shape. These little cups are seen at H′ and K′, and in figure 63 at H
and K. The horizontal section shows, also, the position of the magnets
in the instrument, with the beaks of the pens near the continuous band,
or ribbon of paper, E, which is brought in front of the pens vertically
from below, over a small roller, F. The paper is supplied from a large
roll on a wooden cylinder, upon which is a cog wheel, and connected
with a train of wheels and a vane, to regulate the rate of supply. The
paper is drawn along before the pen by being wound upon a cylinder,
T, concealed by the paper, and on the same shaft with the barrel, M,
upon which is wound a cord supporting a weight, N, below. The shaft is
supported in the standards, _o_ and _o_, which are fastened to a plate
of brass, P and P, also secured to the platform of the instrument. The
barrel revolves in the direction of the arrow upon it.
When the electricity is transmitted through the coil of the indicator,
both magnetic bars, D′ and D′, make an effort to turn in a similar
direction upon their vertical axis, _a_ and _b_. One of the cups of
ink, therefore, advances towards the paper, while the other recedes. To
limit this action, two plates, V and V′, are fastened at the opposite
ends of the free space, allowed for the play of the bars, and against
which the other ends of the bars press. Only the end of one bar can,
therefore, start out from within the multiplier at a time, the other
being retained in its place. In order to bring the magnetic bars back
to their original position, as soon as the deflection is completed,
recourse is had to two small movable magnets, a portion of which is
seen at N and S, whose distance and position are to be varied till
they produce the desired effect. This position must be determined by
experiment, inasmuch as it depends upon the intensity of the current
called into play.
Having described the instrument, its operation is as follows: At the
_transmitting_ station is the pole changer, such as we have described
in figures 48, 49 and 50, and the magneto electric machine such as is
described in figures 45, 46, and 47, and are properly connected, and
in the circuit with the instrument of the _receiving_ station, such
as we have just described. For one single circuit, one wire extends
from the transmitting to the receiving station, the return half of the
circuit is the earth. Thus the current passes from the generator along
the extended wire to the receiving station, and to the copper plate,
then returns through the ground to the copper plate of the transmitting
station, to the pole changer and the magneto electric machine. Thus the
circuit is complete.
It is clear, from what has preceded, that when the pole changer is
thrown to the left side, (the machine being in operation,) the fluid
is made to pass in the direction of the arrows, shown at P and N. Then
the N′ pole of the left hand magnet advances with its pen, K′, to the
paper, E, and a dot is made, and the S′ pole of the right hand magnet
recedes with its pen, H, from the paper, until the other end of the
magnet strikes the stop, V′. Now, if the letter to be formed, requires
two dots in succession from the same pen, the circuit is broken, and
the fixed magnets, N and S, bring back the deflecting magnets, D′ and
D′, to their former position, when the pole changer is again thrown to
the left, and the magnets are deflected in the same manner as at first.
Thus two dots are marked upon the paper, on the right hand line. But,
now, let the pole changer be thrown to the right hand side, and the
current is reversed. The N′ pole of the left hand magnet, with its pen,
K, recedes from the paper until it strikes the stop, V, and the S pole
of the right hand magnet, with its pen, H′, advances to the paper and
makes its dot upon it on the _left_ hand line. The pole changer is then
instantly brought to the middle position, and the magnets resume their
natural place, by the assistance of the stationary magnets, N and S.
The sign which has been marked upon the paper during this operation is
··
· and represents 9.
The following represents Mr. Steinheil’s telegraphic alphabet:
· ·· · ·· ·· ···· · · · · ·
· · · · · · · ···· · · ·· ··
A B D E F G H CH SCH I K L
··· ·· · · ·· · · · · · ··
··· ·· ·· ·· · · · · ··
M N O P R S T V W Z
··· · ·· ·· · ··· · · · · ··
· · · · ··· · ·· ·· · ··· · ···
1 2 3 4 5 6 7 8 9 0
_Masson’s Electric Telegraph._
“In 1837, M. Masson, Professor of Philosophy at Caen, made trial of
an electric telegraph, at the college of that city, for a distance of
about 600 metres. He employed, for developing the galvanic current,
an electro magnetic apparatus, similar, on the contrary, to that of
Mr. Pixii, and made it act on magnetic needles placed at two ends of
the circuit. Since that time, however, M. Masson has endeavoured to
simplify and gradually improve his apparatus.”[33]
[33] Report of the Academy of Industry, Paris, 1839.
_Davy’s Needle and Lamp Telegraph._
The following extracts from the London Mechanic’s Magazine, vol. 28,
page 296 and 327, 1837, is all the description we are able to find in
relation to it:
“There is a case, which may serve as a desk to use in writing down
the intelligence conveyed; and in this, there is an aperture about
sixteen inches long, and three or four wide, facing the eyes, perfectly
dark. On this the signals appear as luminous letters, or combinations
of letters, with a neatness and rapidity almost magical. The field of
view is so confined, that the signals can be easily caught and copied
down without the necessity even of turning the head. Attention, in
the first instance, is called by three strokes on a little bell; the
termination of each word is indicated by a single stroke. There is
not the slightest difficulty in decyphering what is intended to be
communicated.”
_Extract from page 327._
“In front of the oblong trough, or box, described by your
correspondent, a lamp is placed, and that side of the box next the
lamp is of ground glass, through which the light is transmitted for
the purpose of illuminating the letters. The oblong box is open at the
top, but a plate of glass is interposed between the letters and the
spectator, through which the latter reads off the letters as they are
successively exposed to his view. At the opposite side of the room,
a small key board is placed, (similar to that of a piano forte, but
smaller,) furnished with twelve keys; eight of these have each three
letters of the alphabet on their upper surfaces, marked A, B, C; D, E,
F; and so on. By depressing these keys in various ways, the signals or
letters are produced at the opposite desk, as previously described, how
this is affected is not described by the inventor, as he _intimated_
that the construction of certain parts of the apparatus _must remain_
SECRET. By the side of the key board, there is placed a small galvanic
battery, from which proceeds the wire, 25 yards in length, passing
round the room. Along this wire the shock is passed, and operates upon
that part of the apparatus which discloses the letters or signals.
The shock is distributed as follows: The underside of the signal keys
are each furnished with a small projecting piece of wire, which, on
depressing the keys, is made to enter a small vessel, filled with
mercury, placed under the outer ends of the row of keys; a shock is
instantly communicated along the wire, and a letter, or signal, is as
instantly disclosed in the oblong box. By attentively looking at the
effect produced, it appeared as if a dark slide were withdrawn, thereby
disclosing the illuminated letter. A slight vibration of the (apparent)
slide, occasionally obscuring the letter, indicated a great delicacy
of action in this part of the contrivance, and although not distinctly
pointed out by the inventor, is to be accounted for in the following
manner: when the two ends of the wire of the galvanic apparatus are
brought together, over a compass needle, the position of the needle is
immediately turned, at right angles, to its former position; and again,
if the needle is placed with the north point southward, and the ends
of the wire again brought over it, the needle is again forced round to
a position at right angles to its original one. Thus, it would appear,
that the slide or cover over the letters, is poised similarly to the
common needle, and that by the depression of the keys, a shock is
given in such a way as to cause a motion from right to left, and _vice
versa_, disclosing those letters, immediately, under the needle so
operated upon.”
_Alexander’s Electric Telegraph, from the (Scotsmen) Mechanic’s
Magazine, Nov. 1837._
“A model to illustrate the nature and powers of this machine was
exhibited on Wednesday evening at the Society of Arts in Edinburgh.
The model consists of a wooden chest, about five feet long, three
feet wide, three feet deep at the one end, and one foot at the other.
The width and depth in this model are those which would probably be
found suitable in a working machine, but it will be understood that
the length in the machine may be a hundred or a thousand miles, and
is limited to five feet in the model, merely for convenience. Thirty
copper wires extend from end to end of the chest, and are kept apart
from each other. At one end (which, for distinction’s sake, we shall
call the south end) they are fastened to a horizontal line of wooden
keys, precisely similar to those of a piano forte; at the other, or
north end, they terminate close to thirty small apertures, equally
distributed in six rows of five each, over a screen of three feet
square, which forms the end of the chest. Under these apertures on
the outside, are painted, in black paint, upon a white ground, the
twenty-six letters of the alphabet, with the necessary points, the
colon, semicolon, and full point, and an asterisk, to denote the
termination of a word. The letters occupy spaces about an inch square.
The wooden keys, at the other end, have also the letters of the
alphabet, painted on them in the usual order. The wires serve merely
for communication, and we shall now describe the apparatus by which
they work.
This consists, at the south end, of a pair of plates, zinc and copper,
forming a galvanic trough, placed under the keys; and at the north end,
of thirty steel magnets, about four inches long, placed close behind
the letters painted on the screen. The magnets move horizontally on
axes, and are poised within a flat ring of copper wire, formed of the
ends of the communicating wires. On their north ends they carry small
square bits of black paper, which project in front of the screen,
and serve as opercula, or covers, to conceal the letters. When any
wire is put in communication with the trough at the south end, the
galvanic influence is instantly transmitted to the north end; and in
accordance with the well known law, discovered by Oersted, the magnet
at the end of that wire instantly turns round to the right or left,
bearing with it the operculum of black paper, and unveiling a letter.
When the key, A, for instance, is pressed down with the finger at the
south end, the wire attached to it is immediately put in communication
with the trough; and at the same instant, letter A, at the north end
is unveiled, by the magnet turning to the right, and withdrawing the
operculum. When the finger is removed from the key, it springs back to
its place; the communication with the trough ceases; the magnet resumes
its position, and the letter is again covered. Thus by pressing down
with the finger, in succession, the keys corresponding to any word or
name, we have the letters forming that word, or name, exhibited at the
other end; the name VICTORIA, for instance, which was the maiden effort
of the telegraph on Wednesday evening.”
[Illustration: FIG. 65.]
The above description is all that we have been able to obtain in
relation to this plan of an electric telegraph and here introduce,
figure 65, to illustrate it. The 30 needles are represented on the
screen, each carrying a shade, which conceals the letter when the
needle is vertical. The needle belonging to the letter F, is, however,
deflected, and the letter is exposed. The screen is supposed to be at
the _receiving_ station. To the left hand of the screen, 30 wires, _e,
e_, are seen joined to one, _a_; the other 30 wires, _d, d_, are seen
below the screen. These wires may be supposed to extend many miles, and
to be joined with their corresponding wires, _c_, and also _v, v_, of
the _transmitting_ station, where it will be observed, the wire, _c_,
connects with the battery at one pole, and from the other pole a wire
is continued and soldered to the metallic plate, _o, o_, which extend
under all the 30 keys, _i, i_. These keys are each insulated, at their
extremity, by being fastened to a wooden standard, L, L, to which a
wire is soldered. Now, suppose the key, F, is pressed down, (the sixth
key from the left,) the fluid then passes from the battery, B, through
the wire to _o_, the plate; then to the key in contact with it; then to
its wire, marked by the arrow; thence through the extended wire to its
corresponding wire at the receiving station, denoted by the arrow; then
through the coils of the multiplier, deflecting the needle, F; then
returns through its wire, at the left, to the common wire, _a_; then
through the extended wire to C, and the battery, of the transmitting
station. In this manner any letter upon the screen may be indicated.
_Extract from the Report of the Academy of Industry, in reference to a
suggestion of M. Amyot of an Electric Telegraph._
“M. Amyot announced, in a letter addressed to the Academy of Sciences,
in April, 1838, that he also proposed to construct an electric
telegraph. It was to consist of a single current, which would move
a single needle, which needle would of itself write on paper, with
mathematical precision, the correspondence which might be transmitted
to the other extremity, by a simple wheel on which it should be
written by means of points, differently spaced, the same as they are
on the barrels of portable organs. In order to send any news then,
he required to write, by means of movable characters, which must be
constructed in a certain manner, and immediately it would be repeated
and transcribed at the place where he wished to address it, on paper,
which could be put into the hands of persons specially employed to
transmit despatches. But all that method of execution, which it seems
ought to move is clock work, not having been sufficiently described
by the author, the _most vague uncertainty_ yet reigns as to the true
construction of that apparatus, which appears to us to have been for
M. Amyot, rather the occasion, than the end, of this communication;
for indeed he attempted to make the possibility admitted of
establishing a universal telegraphic language of his invention.”
_Edward Davy’s Electric Telegraph._[34]
The following description of Mr. Davy’s telegraph is taken from his
specification and drawings, published in the Repertory of Patent
Inventions. Although the specification has given the basis of his plan,
yet the description contained therein, and the drawings representing
his plan, are so obscure and deficient, that to have given it to
the public in that form, would have represented it as perfectly
impracticable. He has failed to state the number of signals which it
is capable of giving. He has committed great errors in the arrangement
of his wires for producing signals. He has introduced two keys, which
produce the same signals as two others in the same arrangement. He
has employed three extended wires for communicating from one station
to another station, and by his arrangement of them, could not have
obtained more than four signals. He has also very obscurely described
his escapement, by which his marking cylinder is made to advance one
division at a time for receiving the signals. This latter difficulty,
however, we have been enabled to clear up, by a description of it in
a work published by Mr. Bain. Notwithstanding the imperfections and
obscurities of his specification and drawings, we have endeavoured to
carry out his plan, and give it a practical shape, perhaps, as Mr. Davy
originally designed it.
[34] From the Repertory of Patent Inventions, No. lxvii. New Series,
London, July, 1839.—Sealed, July 4th, 1888.
As it is now described, there are 26 signals, or marks, indicating
letters. The employment of four wires instead of three, or if Mr. Davy
chooses to use for the common communicating wire the ground, which is
perfectly practicable, it will reduce the number to three, the number
he has specified. We have introduced one key more, and so arranged the
two superfluous keys as to make them available. With this preliminary,
we will proceed with the description.
[Illustration: FIG. 66.]
[Illustration: FIG. 67.]
Figure 66 represents a top view of the arrangement of the wires,
mercury cups, and batteries of the _transmitting station_. The close
parallel lines represent the wires, of which D, A, B and C are those
which proceed to the receiving station. 1′, 2′ and 3′ are the three
batteries, of which, P and N are their respective poles. The small
circles formed at the termination of the wires, and marked 7, 1, 10, 2,
20, &c. are mercury cups, in which the terminating wires are immersed.
The wires 1 and 20, and 2 and 10, &c. which cross each other, are not
in contact, but perfectly insulated. The wires shown in this figure,
are all secured permanently, with their mercury cups, to one common
base board. The letters H, J, K, M, O and U represent the places of the
six finger keys, used in transmitting signals. There is, also, another
key at 7, for uniting the wire, D and D. In this figure, however,
the keys themselves are omitted, in order to render more clear the
arrangement of wires under and around them. Another figure, 67, is
here introduced to illustrate the plan of one set of wires and their
two keys. In figure 67 is represented, in a top view, the two wooden
keys, A and B, and their axes, at E and F. G is the battery, of which,
9 is the positive pole, and 10 the negative pole. The small circles,
marked 1, 2, 3, 4, 5, 6, 7 and 8 represent the mercury cups. C and C′,
and also, D, are the extended wires. The keys, A and B, have each two
wires, passing at right angles through the wooden lever. The wires of
the key, A, are marked 1 and 2, and 5 and 6, and those of the key, B,
are marked 3 and 4, and 7 and 8. These wires, directly over the mercury
cups, are bent down a convenient length, so as to become immersed in
the cups, when the lever is depressed, and rise out of them, when the
lever is elevated. Now, if the key, A, is depressed, the cup, 1, is
brought in connection with cup 2; and 5 is connected with 6, by the
wires, supported by the lever, being immersed in the mercury; and the
key, B, not being depressed, there is no connection of the cup 3 with
4; or 7 with 8. At X and X, under the lever, are springs, which keep
the lever elevated; and, consequently, the wires out of the cups, when
the keys are not pressed down.
[Illustration: FIG. 68.]
Figure 68 represents a side view of the lever, or key, A, and its
axis at E. R is the platform supporting the standard of the axis;
the stationary wires; the battery, G; and the mercury cups, _a, a_
and 10. X is the spiral spring, for the purpose of carrying back the
lever, after the finger is taken off and sustaining it in its elevated
position. Through the centre of the spiral, passes a rod, with a head
upon it at the top of the lever, to limit its upward motion. At its
lower end, the rod is secured in the platform, R. 4 and 8 are the two
wires supported by the lever, A, and are seen to project down directly
over the mercury cups, _a_ and _a_, so that by depressing the key, they
both enter the cups and form a metallic connection. The key, B, figure
67, has the same fixtures and is similarly arranged as the key, A,
represented above.
[Illustration: FIG. 69.]
Figure 69 represents a top view of die arrangement of multipliers
at the _receiving_ station. R′, R′ and R′; R, R, and R are six
magnetic needles, or bars, each of which move freely upon a vertical
axis passing through their centres. The lower point of their axes
is immersed in cups of mercury, in which also terminate the wires,
I, I, I and L, L, L. The wires, D″, A′, B′ and C′, are those coming
from the _transmitting_ station. A′, B′ and C′, each enter the needle
arrangement, and first passing from left to right, over the magnetic
bars, R′, R′ and R′, in the direction of their length, then down and
under and round, making many turns, leave these three needles and
pass _under_ the needles, R, R and R, and in like manner from right
to left round them, making a number of turns, then pass off and unite
together, in the wire, 9, which is a continuation of D″. This wire is
called the _common communicating wire_,[35] and the wires, A′, B′ and
C′ are called _signal wires_. At right angles, there projects from each
magnetic bar, a metallic tapered arm, which rests against the studs,
V, V, V, V, V, V, when the needle is undisturbed. But when the needles
are made to move in the direction, to carry the arms to the left, they
are brought in contact with the metallic stops, S, S, S and T, T, T.
To each of these stops, it will be observed, a wire is soldered, and
continued respectively from S, S, S to ̈1, ̈3, ̈5, and from T, T, T to
̈2, ̈4, ̈6. It will also be observed, that from each of the mercury
cups below the magnetic bars, the wires, I and L, and I and L, and
I and L, proceed and unite in pairs at, L, L, L; these three united
wires are then continued, and the whole are joined in one at 8. The
wires, ̈1, ̈2, ̈3, ̈4, ̈5, ̈6, are continued, in a manner hereafter
to be described, and are connected with one pole of a battery. The
wire, 8, is also continued and connected with the other pole. So that
if any one of the needles should be made to move its arm to the left,
thereby coming in contact with its metallic stop, the circuit would be
complete and the current would pass along the wire, ̈1, for example,
to the metallic stop, then to the arm, and to the magnetic bar; then to
the axis; then to the mercury; then to the wire, I, and thence to the
wire, 8. In the same manner the current would pass if any other arm was
brought against _its_ metallic stop. All the wires represented in this
figure are permanently secured in their places upon a common platform.
[35] A′, B′ and C′ are also, occasionally, common communicating wires.
In order to understand the combined operation of the keys and needles,
figure 70 is here introduced. The right hand figure, is the same as
figure 69, and the left hand the same as figure 66.
[Illustration: FIG. 70.
_Transmitting Part of Receiving_ _Station. Station._]
The wires, D″, A′, B′ and C′, are detached from their corresponding
wires of the transmitting station, and it may be imagined that many
miles of wire intervene and connect the two. In the left hand figure,
those mercury cups above and below, 1 and 10, are joined by two
wires passing through a moving lever, in the same manner as has been
described in figure 67. We will, therefore, call the key, carrying
these two connecting wires, H. In like manner the key for the cups
above and below the numbers, 2 and 20, is called J; for 3 and 30, is
K; for 4 and 40, is M; for 5 and 50 is O; for 6 and 60, is U. The key
which connects the two mercury cups on the right and left of number 7,
of the wire, D″, is called 7. There are 7 keys; two for each battery,
1′, 2′ and 3′, and each wire, A′, B′ and C′; and one for the common
wire, D″.
It will now appear, that if the key, U and 7, are depressed, the cups
above and below, numbers 6 and 60; and the cups on each side of number
7, will be connected together so that the current leaving, P, or the
positive pole of the battery, 3′, goes to the lower cup, 50; then by
the stationary cross wire to upper cup, 6; then passes to lower cup,
6, by the wire supported by the lever, U, which is now pressed down,
and its ends immersed in the two cups; then along the wire, D, to the
left hand cup, 7; then to the right hand cup, 7, by the wire supported
by the lever, 7, and which is immersed in the two cups; then through
the extended wire to D″, of the _receiving_ station; then through 9,
to the two multiplying coils of the wire, C′, deflecting the arm of
the needle, R, to the right, against the stop, V; and the arm of the
needle, R′, to the left against the metallic stop, S, as indicated by
the arrow at S; then along the extended wire, back to the lower cup,
60, of the _transmitting_ station; then to upper cup, 60, through the
wire supported by the lever, U; then to N, the negative pole of the
battery, 3′.
It will be observed of the two needles, R and R′, in the circuit of the
same wire, C′, that if R is deflected to the right against the stop,
V, then R′ will be deflected to the left against the metallic stop, S.
The current, to produce these deflections, being through the wire C′,
in the contrary direction to that indicated by the arrow of the wire,
C′. But if R is deflected to the left against the metallic stop, T,
then R′ will be deflected to the right against the stop, V. The current
to produce these deflections, will then be through the wire, C′, in
the direction of the arrow of that wire. The same effect is produced
upon the two other pairs of needles of the wires, A′ and also B′. These
contrary movements of the two needles, when a _current_ is passing, are
produced by the coils being so wound, (see figure 69,) that the wire
passes round one needle in a contrary direction to what it does round
the other.
If, now, we depress the keys, O and 7, the cups above and below, 5 and
50, and on each side of number 7, will be connected. The fluid will
then pass from P or positive pole of the battery, 3′, to the lower
cup, 50; then through the key wire to upper cup, 50; then along the
extended wire, C′ to the _receiving_ station; then through the coils
of the multipliers, deflecting the arm of the needle, R, to the left
against the metallic stop, T; and the arm of the needle, R′, to the
right against the stop, V, as indicated by the arrow at V; then to
wire, 9 and D″; then along the extended wire back to the _transmitting_
station, to the right hand cup, 7; then by the key wire to the left
hand cup, 7; then to wire, D; then to upper cup, 5; and through the key
wire to lower cup, 5; then by the cross wire to upper cup, 60, and then
to N, or negative pole of the battery.
We have now shown the route of the current, when the keys, U and 7; and
the keys, O and 7, were depressed. It will be observed, that when the
keys, U and 7 were used, the current through the wire, D″, was from
_left_ to _right_; and when the keys, O and 7, were used, the current
was from _right_ to _left_. Thus, by means of the six keys, the current
of each battery may be made to pass in either direction through the
_common communicating_ wire, D″. By the keys, U, M, J, with 7, the
current is made to pass from _left_ to _right_ along the wire, D″. By
the keys, O, K, H, with 7, the current is made to pass from _right_
to _left_ along the wire, D″. By these six keys, all those various
deflections of the six needles are produced, which are necessary
to close the circuit of such of the wires, ̈1, ̈2, ̈3, ̈4, ̈5, ̈6, with
the wire, 8, as are required for marking the signals desired, on an
instrument now to be described.
[Illustration: FIG. 71.]
[Illustration: FIG. 72.]
Figure 71 represents a top view of that part of the instrument at the
_receiving_ station, by which the signals are recorded. The seven
wires on the left of the figure are a continuation of those wires,
marked ̈1, ̈2, ̈3, ̈4, ̈5, ̈6, and 8, in figure 70. The first six pass
through a wooden support, _b_ and _b_, and terminate upon the edge of
the platinum rings, _a_, _a_, _a_, _a_, _a_ and _a_, forming a metallic
contact. The six platinum rings surround a wooden insulating cylinder,
_t_, which revolves upon axes in the standards, _h_ and _i_. The rings
are _broad_ where they come in contact with the wooden roller, and are
bevelled to an _edge_ where they come in contact with the six wires.
Y represents a compound battery, with one pole of which, wire 8, from
the needle arrangement, figure 70, is connected, and from the other
pole the wire proceeds to the electro magnet, Z, Z; it then passes on
and is brought in connection with the metallic cylinder, _d_, at the
point, _g_. The cylinder, _d_, revolves upon axes, and is supported in
the standards, _k_ and _l_. To the cylinder is attached a barrel, _n_,
upon which is wound a cord, supporting the weight, _e_, by which the
cylinder is made to revolve. C′, C′, represents a prepared fabric, such
as calico, (impregnated with hydriodate of potass and muriate of lime,)
and is placed between the platinum rings, _a, a, a, a, a, a_, and the
metallic cylinder, _d_; _o_ is a cog wheel upon the end of the axis of
the cylinder, _d_, and is connected with other machinery, omitted here,
but shown in figure 72, which is a side elevation of part of figure
71: _o_ is the cog wheel, (figure 72,) on the arbor of the cylinder,
_d_. B and B, are the two sides of the frame containing the clock work,
and is secured to the platform, R: _d_ is a part only of the metallic
cylinder, upon which is seen a portion of the prepared fabric, K. The
cog wheel, _o_, drives the pinion, A, on the shaft of the fly vane,
G. M is an end view of the electro magnet, (represented by Z, Z, in
figure 71,) of which N and P are the two ends of the wire composing
the helix. D is its armature, constructed so as to move upon an axis
represented by two small circles. To the armature are connected, and
capable of moving with it, two arms, E and I, which project, so as to
come in contact with the pallet, _a_, of the fly, G. F is a spiral
spring, one end of which is fastened to the armature, D, and the other
passes through a vertical hole in the screw, S, in the bar, T, by which
the armature is held up in the position now seen, when not attracted
by the electro magnet. Now, if the wires, N and P, connected with
battery, Y, (figure 71,) have their circuit closed, the current passing
through the helix of the magnet, M, brings down the armature, D, in
the direction of the arrow, which raises the arm, I, against which the
pallet, _a_, of the fly vane, is resting, and releases the fly. It then
makes a half revolution and is again arrested by the pallet against
the lower arm, E, and the cylinder, _d_, with its fabric, has advanced
a half division. If the circuit is now broken, the armature, D, is
carried up by the spring, F, at the same time the arm, E, releases the
pallet, _a_, and the fly makes another half revolution, and is again
stopped by the arm, I. The cylinder has now made another advance of
half a division, which, together, makes a whole division the fabric has
advanced. The purposes for which this is designed will now be described.
[Illustration: FIG. 73.]
Figure 73 represents a top view of the whole apparatus of the
_receiving_ station. The fabric, C′, C′, is marked in equal divisions
across it, and in six equal divisions, in the directions of its
length, thus marking it into squares. Each platinum ring, _a, a, a_,
&c. (when the instrument is not in operation,) is in contact with the
fabric at the _middle_ of the squares across the fabric. It will be
observed, that the wires ̈1, ̈2, ̈3, ̈4, ̈5, ̈6 are in connection with
the battery, Y, and the circuit complete, except at the arms of the
needles. Suppose, for example, the arm of the needle, R′, of the wire,
C′, is brought up against the stop of the wire, ̈5, at S; the circuit
is then closed, and the current leaves the battery, and passes to
the electro magnet, (causing the cylinder and fabric to move half a
division,) then to the metallic cylinder, _d_; then through the fabric,
_c′, c′_, resting upon the cylinder, (where it is in contact with
the platinum ring, _a_, of the wire, ̈5,) then to the platinum ring;
then to wire ̈5; then to the metallic stop, S; then to the arm of the
needle, R′, along its axis to the mercury; then to the wire, I; then
to wire, 8, and to the other pole of the battery, Y. Thus a current is
passed through the prepared fabric, and a mark produced thereon, in the
middle of its square. If the circuit is now broken, the cylinder moves
another half division, which will bring the rings to the centre of the
squares, ready for the next signal.
But one battery, Y, is used for all the six circuits, formed with the
wire, 8; so that, when three of the circuits are closed at the same
instant, as will be shown hereafter, the current passes through the
three wires of their respective circuits, making each their appropriate
mark upon the fabric.
We now proceed to describe the manner of operating with the two
instruments, at their respective stations: and, first, we must here
designate each needle by its own peculiar mark of reference. Let the
two needles upon the wire, A′, be denoted by, A, S and A, T; those of
the wire, B′, by B, S and B, T; and those of the wire, C′, by C, S and
C, T. It will appear obvious, from the foregoing description, that
but _one_ needle of each _wire_, A′, B′, C′, can be made to close its
circuit at the same instant. However, _two_ needles, or _three_ needles
of _different wires_, may close their circuits at the same instant,
but no higher number than three. The various combinations of _one_
mark, _two_ marks, and _three_ marks, upon the same row of six cross
divisions of the fabric, constitute the characters representing letters.
[Illustration: FIG. 74.
LONDON.—_Transmitting Station._]
Figure 74 represents the _transmitting_ station, which may be supposed
to be _London_, and figure 75, the _receiving_ station, which may be
at _Birmingham_, with four wires extending from station to station, or
three only, if the _ground_ be substituted for the wire, D, D″. The
wires, D, A, B and C, are supposed to be united with D″, A′, B′ and C′,
respectively. Now, if we depress the keys, in the following order, we
shall, for each key, have the following deflections of the two needles,
belonging to each key.
No. 1.
The keys, H, 7, moves the arm, A, S, to the right, A, T, to the left.
“ J, 7, “ A, S, “ left, A, T, “ right.
“ K, 7, “ B, S, “ right, B, T, “ left.
“ M, 7, “ B, S, “ left, B, T, “ right.
“ O, 7, “ C, S, “ right, C, T, “ left.
“ U, 7, “ C, S, “ left, C, T, “ right.
These are all the various deflections which it is possible to give the
six needles. Those, however, which deflect to the right, not closing
the circuit, produce no effect, and are of no account. We will,
therefore, omit them, and simply give the table, thus:
No. 2.
The keys, H, 7, move the arm A, T, to the left. No. 1.
“ J, 7, “ A, S, “ “ 2.
“ K, 7, “ B, T, “ “ 3.
“ M, 7, “ B, S, “ “ 4.
“ O, 7, “ C, T, “ “ 5.
“ U, 7, “ C, S, “ “ 6.
[Illustration: FIG. 75.
BIRMINGHAM.—_Receiving Station._]
In the following table, the first column represents the keys, which
when depressed, produce a deflection of the needles, (represented in
the columns, second, third and fourth,) by means of their batteries,
and thus closing the circuit of the wires, ̈1, ̈2, ̈3, ̈4, ̈5 and ̈6,
by which the fluid, is made to pass through the prepared fabric, and
mark upon its space, or spaces, numbered 1, 2, 3, 4, 5 and 6, in the
fifth column. In the sixth column are the letters which the marks upon
the fabric are intended to represent.
Keys. Needles. Needles. Needles. Spaces on Fabric. Letters.
H, 7, A, T, - - 1, A.
J, 7, A, S, - - 2, B.
K, 7, B, T, - - 3, C.
M, 7, B, S, - - 4, D.
O, 7, C, T, - - 5, E.
U, 7, C, S, - - 6, F.
H, K, 7, A, T, B, T, - 1, 3, G.
J, M, 7, A, S, B, S, - 2, 4, H.
K, O, 7, B, T, C, T, - 3, 5, I.
M, U, 7, B, S, C, S, - 4, 6, J.
H, O, 7, A, T, C, T, - 1, 5, K.
J, U, 7, A, S, C, S, - 2, 6, L.
H, M, A, T, B, S, - 1, 4, M.
J, K, A, S, B, T, - 2, 3, N.
K, U, B, T, C, S, - 3, 6, O.
M, O, B, S, C, T, - 4, 5, P.
H, U, A, T, C, S, - 1, 6, Q.
J, O, A, S, C, T, - 2, 5, R.
H, K, O, 7, A, T, B, T, C, T, 1, 3, 5, S.
J, M, U, 7, A, S, B, S, C, S, 2, 4, 6, T.
H, K, U, A, T, B, T, C, S, 1, 3, 6, U.
J, M, O, A, S, B, S, C, T, 2, 4, 5, V.
H, M, U, A, T, B, S, C, S, 1, 4, 6, W.
J, K, U, A, S, B, T, C, S, 2, 3, 6, X.
H, M, O, A, T, B, S, C, T, 1, 4, 5, Y.
J, K, O, A, S, B, T, C, T, 2, 3, 5, Z.
_Telegraphic Letters._
1 · · · · · · · · ·
2 · · · · · · · · ·
3 · · · · · · · · ·
4 · · · · · · · · ·
5 · · · · · · · · ·
6 · · · · · · · · ·
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
The above represents the telegraphic characters marked upon the
prepared fabric. The spaces are numbered from the top.
The first six of the telegraphic letters require each a signal wire,
and the common wire, D, with one battery.
The next six require each two signal wires, with two batteries, whose
joint currents pass in the same direction on the common wire, D.
The next six require each two signal wires only, with two batteries,
joined together so as to form a compound battery. The negative pole of
one, connected with the positive pole of the other.
The next two require each three signal wires, with three batteries,
whose joint currents pass in the same direction along the common wire,
D.
The next six require each, three _signal_ wires only, with three
batteries. One of the signal wires with its battery is used as a common
wire for the other two. Hence the current of the two batteries of the
two signal wires unite in one, and are connected with the battery of
the common wire as a compound battery.
With what rapidity these letters may be formed, does not appear, or to
what extent the plan has been carried out.
_Bain’s Printing Telegraph._
The following description of Mr. Bain’s plan of what he calls an
_electro magnetic_ printing telegraph, is taken from a work entitled,
“An account of some remarkable applications of the electric fluid to
the useful arts, by Alexander Bain. Edited by John Finlaison, Esq.
London, 1843.”
It appears from this work that Mr. Bain’s plan was invented in 1840,
and the following certificate is given in reference to the date of its
first operation.
PERCEIVAL STREET, CLERKENWELL, _Aug. 28, 1842_.
DEAR SIR—In reference to your application,
I recollect visiting you at your apartments in Wigmore
street, early in July, 1840, when you showed me the model
of your _electro magnetic_ printing telegraph, with which
you printed my name at the time. You also showed me a model
of your electro magnetic clock, and explained to me the
principles and utility of them.
I remain, dear sir, yours, respectfully,
ROBERT C. PINKERTON.
To MR. ALEXANDER BAIN.
[Illustration: FIG. 76. PORTSMOUTH.]
[Illustration: FIG. 77. LONDON.]
Figures 76 and 77 exhibit the arrangements of Mr. Bain’s telegraph.
Both figures are the same, representing one as being at _Portsmouth_,
and the other at _London_. The same letters will refer to either
instrument: _d_, _i_ and _h_, represent the signal dials, insulated
from the machine. X is a hand or pointer. The small dots represent
twelve holes in the dial, corresponding with the twelve signals, and
two blanks, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0. U is a similar hole over the
starting point of the hand, X. R is a coil of wire, freely suspended
on centres. K and K, is a compound permanent magnet, placed within the
coil, and immovably fixed upon the frame of the machine. J and J are
sections of similar permanent magnets. S is a spiral spring, (and there
is another on the opposite side,) which conveys the electric current
to the wire coil, and at the same time leaves the coil free to move
in obedience to the magnetic influence. So long as the electricity
is passing, the wire coil continues to be deflected, but the instant
the electric current is broken, the springs, S, bring back the coil
to its _natural position_.[36] L is an arm fixed to, and carried by
the wire coil, R and R, to stop the rotation of the machinery. B is a
main spring barrel, acting on the train of wheels, G, H and I, which
communicate motion to the governor, W, and the hand, X. On the arbor
of the wheel, H, is fixed a type wheel, C, at a little distance from
the paper cylinder, A, on which the messages are to be imprinted. P
is a second main spring barrel, with its train of wheels, M, O. Q, is
a fly, or vane. On the arbor of the wheel, _o_, there is a crank, V,
and two pallets, _a_ and _b_, which prevent the train of wheels from
rotating, by coming in contact with the lever, Z. When the telegraph is
not at work, a current of electricity is constantly passing from the
_Portsmouth plate_, buried in the ground, through the moisture of the
earth, to the plate in the ground at the _London_ station. From the
copper plate of that station the electric current passes up through
the freely suspended multiplying coil, R and R, (which it deflects to
the horizontal position,) into the machinery, and thence to the dial,
by means of a metal pin, inserted in the hole, U; from the dial it
passes by a single insulated conducting wire, 1, suspended in the air,
back to the first machine; traversing which, it passes through the
freely suspended multiplied coil, R and R, which it deflects, also, to
the horizontal position to the plate from whence it started, and thus
completes the circuit.
[36] Mr. Bain means, by the _deflected position_ of the coil, (when the
current is passing,) its _horizontal_ position, as shown in the figure.
Its _natural_ position, (when the current is broken,) is the elevation
of the left hand end of the coil, in the direction of the arrow,
carried up by the power of the spring, at the centre of the coil.
This action of the spring is overcome, when the current is passing,
to such a degree, as to bring the coil to the horizontal position as
represented in the figure.
“When a communication is to be transmitted from either end of the line
(one station only being able to transmit at a time,) the operator draws
out the metal pin from the hole, U, in the dial of his machine; the
electric circuit is then broken, and the ends of the multiplying coils,
R and R, at both stations are carried upwards, in the direction of the
arrow, by the force of the spiral springs. The arms, L, attached to
the two coils, moving to the right, release the lever, Y, which leaves
the machinery free to rotate, and as the moving and regulating powers
are the same at both places,[37] the machines go accurately together;
that is, the hands of both machines pass over similar signals at the
same _instant_ of time, and similar types are continually brought
opposite to the printing cylinders at the same moment. An inspection
of the wheel work will show, that this movement will have caused the
governor, W, to make several revolutions, and the divergence of the
balls, in obedience to centrifugal force, will have raised one end of
the lever, Z, and depressed the other, which allows the pallet, _a_,
to escape; but the rotation of the arbor is still opposed by contact
with the second pallet, _b_. The operator having inserted the metal
pin in the hole, under the signal which he wishes to communicate, the
moment the hand of the dial comes in contact with it, the circuit is
again completed, and both machines are stopped instantly. The governor
balls, collapsing, depress the left hand end of the lever, Z, clear
the pallet, _b_, and this allows the crank spindle, V, to make one
revolution.
[37] It is absolutely necessary to the certain and accurate performance
of the two machines, that their movements should be synchronical, or
else a different figure, or signal, from that intended by the operator
at the transmitting station, may be given at the receiving station.
“The motion of the crank by means of the crank rod, T, acting on the
lever, E, presses the type against the paper cylinder, A, and leaves an
impress upon the paper; at the same time, a spring, _e_, attached to
an arm of the lever, E, takes into a tooth of the small ratchet wheel,
D, on the spindle of the long pinion, F, which takes into and drives
the cylinder wheel; so that the crank apparatus, going back to its
former position, after impressing a letter, moves the signal cylinder
forward, and presents a fresh surface to the action of the next type.
As the cylinder moves round, it has also a spiral motion upward, which
causes the message to be printed in a continuous spiral line until the
cylinder is filled.[38] In order to mark, in a distinct and legible
manner, the letters printed by the apparatus, two thicknesses of
riband, saturated with printing ink and dyed, are supported by two
rollers so as to interpose between the type wheel and the cylinder;
(the rollers are not shown in the figure, to prevent confusion.) If a
second copy of the message, thus simultaneously printed at two distant
places, is desired at either, a slip of white paper is placed between
the ribands to receive the imprint at the same time as the cylinder.”
[38] This contrivance for moving the paper is exactly similar to that
in Prof. Morse’s _first model_ of his telegraph, made in 1837, for the
Patent Office.
[Illustration: FIG. 78.]
Figure 78 represents a top view of the coil and magnets of Mr. Bain’s
machine. B is the compound permanent magnet, with six bars. N is the
north pole, and S the south pole. A, A are the sides of the brass frame
containing the coils; C, C are the spiral springs on each side: _a_ and
_a_ is the axis of the coil: _o, o_, is a part of the frame containing
the clock work, (not shown in this figure,) supporting one centre of
the coil, and I and I a support for the other centre. N and P are the
wires, one of which is in connection with the ground, and the other
with the extended wire. When the circuit is closed, and the current
from P pole of the battery is in the direction of the arrow above, and
then through the coil to the other pole, N, in the direction of the
arrow below; the end, D, of the coil, will be depressed, and the end,
U, will rise; reverse the current and the effect is the elevation of
the end, D, of the coil, and the depression of the end, U.
_Wheatstone’s Rotating Disc Telegraph, invented, 1841._
Figure 79 represents that portion of the instrument which belongs to
the _transmitting_ station, of which, K, is a circular disc, with the
alphabet and numerals, marked in two concentric circles upon it: _a_
are handles projecting from its rim, one to every letter, by means of
which, the disc is turned upon its axis, and brought to that position,
_b_, required for signalizing a letter. O is a side view of the disc,
K: _t_ is the rim of the disc, with its holders: _h_ is a portion of
the axis of the disc, shown as broken off: _c_ represents a silver
band surrounding a pulley, or hub, upon the axis, and directly behind
the disc. Upon the hub are metallic ribs, _b_, parallel with its axis,
corresponding in number to the letters on the dial. Each rib forms a
metallic contact with the silver band, _c_, and are separated from each
other by pieces of ivory, fastened to the hub. Both the ribs and ivory
pieces are made perfectly smooth and even upon their surface: _e_ is
a metallic spring with a portion of it pressing against that portion
of the hub between the silver band, _c_, and the disc, _t_, in such a
manner that when the disc is turned, the metallic ribs and ivory pieces
shall alternately come in contact with it. To this spring is soldered
a wire connected with one pole of the battery, _g_, and from the other
pole proceeds the wire, _n_: _d_ is another metallic spring, similar to
_e_, but pressing _only_ upon the silver band, with which it is always
in contact, and to which a wire, _p_, is soldered. Whenever the spring,
_e_, is in contact with any of the metallic ribs, there is a continuous
connection from _n_ to _p_, viz. from _p_, to the spring in contact
with the silver band, _c_, thence to the rib with which the spring,
_e_, is in contact; then to the spring, _e_, then to the battery, _g_,
and then to the wire, _n_. If, however, the disc, O, should be turned,
so that the spring, _e_, is in contact with the ivory, then the circuit
is broken at that point, and in this manner the circuit is alternately
broken and closed as the wheel, O, is turned from one letter to another
by means of the handles at _t_.
[Illustration: FIG. 79.]
[Illustration: FIG. 80.]
Figure 80 represents a side elevation of the dial and clock work of the
_receiving station_. A represents an edge view of the electro magnet,
from which proceed the two wires, _v_ and _i_, which connect with the
wires, _n_ and _p_, of figure 79. J and J is the brass frame containing
the wheel work, C and E; the pin wheel, D; the dial plate, I; and the
barrel, B, which is driven by a weight and cord. In the side of the
wheel, D, are pins projecting from the rim, parallel with the axis, and
are equal in number to the divisions, or letters, upon the dial, I.
They are, however, placed alternately on each side of the rim. F is the
armature of the magnet, fastened upon a horizontal rod, sliding freely
through the standards, 1 and 2. G represents a spring, fastened to the
frame, J, and which carries back the armature, F, when the magnet has
ceased to attract it. From the armature there extends downward an arm,
K, which, as it approaches the pin wheel, D, presents two arms, or
pallets, one on each side of the wheel. These pallets are so arranged
with regard to the pins, that if one pallet releases a pin on one side
of the wheel, the same movement will cause the other pallet on the
other side, to arrest the motion of the wheel by its striking against
the next alternate pin. H and I is an edge view of the circular dial,
enclosed in a case, with a single opening at O, so that only one letter
at a time can be seen. This dial, I, is in every respect marked as the
disc in figure 79.
Figure 81 represents the two instruments. O the _transmitting_
instrument, and the right hand figure the _receiving_ instrument. The
wires, _v_ and _i_, are respectively connected with _p_ and _n_. It
will be observed, that the armature, F, is not attracted, and that
the right hand pallet is checking the pin wheel, so that the dial is
stationary. If, however, the disc, _t_, is turned so that the circuit
is completed, by the contact of the spring, _e_, with one of the ribs,
instantly the armature is attracted by the electro magnet, which will
carry the right hand pallet away from the pin wheel, and which will
then move by the action of the weight upon the barrel, B, until it is
checked by the left hand pallet, which had advanced to the wheel at
the same time the other receded. This single operation has moved the
disc one division and the armature is still attracted. Now let the
disc, _o_, be turned until the spring, _e_, has been passed by the rib,
and is in contact with the ivory only, instantly the current ceases;
the armature, F, recedes from the magnet by the action of the spring,
G; this has taken the left hand pallet from the pin wheel, which is
permitted to move until the next pin strikes against the right hand
pallet. This has now brought another letter in front of the aperture at
H. Thus it will be seen, that the design of this instrument is to bring
into view, at the aperture such letters as are required in transmitting
a message.
[Illustration: FIG. 81.]
Suppose letter A, is at the point, _b_, of the _disc_; and letter A
of the _dial_ is opposite the opening; the instrument is now ready
to transmit, and let the letter, I, be the first of the message. The
operator gently turns the disc round in the direction of the arrow,
so that each time the circuit is broken a new letter appears at the
dial, and each time it is closed by the operation of the pallets, in
checking and releasing the pin wheel. This is its operation until the
letter, I, has reached the point, _b_, when a short pause is made. The
next letter, H, requires but one movement of the disc, then follows, A;
then, V; and then, E.
In relation to this instrument, Professor Daniell says: “We can only
further briefly allude to two of the most important modifications of
this invention, which Prof. Wheatstone has made for specific purposes.
By substituting for the paper disc, on the circumference of which the
letters are printed, a thin disc of brass, cut from the circumference
to the centre, so as to form 24 springs, on the extremities of which,
types, or punches, are placed, and adding a mechanism the detent of
which, acted on by an electro magnet, causes a hammer to strike the
punch against a cylinder, round which are rolled, alternately, several
sheets of white paper, and of the blackened paper used in the manifold
writing apparatus, he has been enabled to obtain, without presenting
any resistance to the type wheel, several distinct printed copies at
the same time of the message transmitted.”[39]
[39] Daniell’s Introduction to Chemical Philosophy, page 580, 2d
Edition, London, 1843
Mr. Wheatstone has recently so modified his telegraph as to use two
needles, or galvanometers, and two extended wires, with the ground as
half the circuit for the two wires. He has thus adopted PROF. MORSE’S
_plan_ of using the ground as a common conductor for two or more wires.
He, however, still requires two wires for _one_ independent line of
communication; one station only being able to communicate at a same
time. He has no mode of recording his message, but depends upon the
watchful eye of the attendant. His code of signals are based upon
Schilling’s plan, heretofore described, page 155, and also Gauss and
Weber’s, page 156, from whom he seems to have obtained his idea.
The two needles, or galvanometers, stand side by side, one of which is
called the _left_ needle and the other the _right_ needle. These two
needles are placed directly in front of the person who transmits. There
are, also, in front, two handles, one for each hand, with which the
operator transmits a message, closing and breaking the circuit of the
two wires. His signals are made thus: The upper half of the left hand
needle moving to the left twice, gives, _a_; three times, _b_; once to
the right and once to the left, _c_; once to the left and once to the
right, _d_; and, in like manner, for the other letters of the alphabet,
as shown in the table which follows.
Left Hand Needle. Right Hand Needle.
ll, A. r, E. | l, H. lr, M.
lll, B. rr, F. | ll, I. r, N.
rl, C. rrr, G. | lll, K. rr, O.
lr, D. | rl, L. rrr, P.
Joint Action of Both Needles.
l, l, R.
ll, ll, S.
lll, lll, T.
rl, rl, U.
r, r, W.
rr, rr, X.
rrr, rrr, Y.
r, completed.
ll, rr, I understand, or yes.
rl, rl, I do not understand, or no.
rl, rl, 1.
lr, lr, 2.
r, r, 3.
l, l, 4.
rl, rl, 5.
lr, lr, 6.
r, r, 7.
l, l, l, l, 8.
ll, ll, ll, ll, 9.
r, r, r, r, 0.
Mr. Wheatstone does not appear to be aware of all the advantages of
this, his latest plan of using two needles and two wires, since some
of his signals for the _numerals_, are repetitions of his _letter_
signals, and require four deflections of a single needle, with a pause
between the two first deflections, and the two last, and for _some_
other signals he requires as many as three deflections of a signal
needle. He has likewise, apparently, for want of simple signals,
omitted the letters, J, Q, V, Z. He could with perfect ease, obtain
from his two wires and two needles, sixty-four different signals,
requiring the time of only two deflections, each, and using but one
hand for manipulating four keys, instead of both hands, as in his
present plan. The author has demonstrated it by actual experiment.
*** End of this LibraryBlog Digital Book "The American Electro Magnetic Telegraph - With the Reports of Congress, and a Description of All - Telegraphs Known, Employing Electricity or Galvanism" ***
Copyright 2023 LibraryBlog. All rights reserved.