Now the article containing these statements was doubtless attributed

to Sir David Brewster in the hope that his name would be accepted as

a guarantee of its accuracy. Fortunately for all concerned, however,

Sir David Brewster had previously placed on record his opinion on

this question of the telegraph in a manner that put it beyond doubt.

Asked by a Committee of the House of Lords in 1851 whether Professor

Wheatstone was the undoubted inventor of the electric telegraph, Sir

David Brewster replied: “Undoubtedly he is.” Further asked whether

there was not a Swede who had paid great attention to the subject, Sir

David said Oersted was the discoverer of electromagnetism, but had

that not been discovered at all, ordinary magnetism was quite capable

of being the moving power in the electric telegraph. He added that

if electromagnetism had been the only means of working a telegraph,

then the merit, not of the telegraph, but of what was necessary to the

existence of the telegraph, would have belonged to Professor Oersted.

When, on the other hand, the same Committee pressed Sir I. K. Brunel

to say whom he considered the inventor of the telegraph, he replied:

“Messrs Cooke and Wheatstone derive a large sum of money from the

electric telegraph; but I believe you will find fifty people who will

say that they invented it also: I suppose it would be difficult to

trace the original inventor of anything.”

It has never been denied, though often overlooked, that Mr. Cooke

obtained his first idea of a telegraph from Professor Möncke of

Heidelberg--a circumstance which detracts from its originality. But the

matter did not rest there.

When Mr. (then Sir) W. F. Cooke died in 1879, Mr. Latimer Clark

published the portion of his private correspondence which related

to his first connection with Professor Wheatstone, and although

Mr. Latimer Clark endeavoured to put everything in the light most

favourable to Mr. Cooke, the letters of the latter in essential points

confirm the case of Professor Wheatstone. For example, after writing

numerous letters to his mother explaining that he was busy trying to

make a telegraph, Mr. Cooke wrote on February 27th, 1837: “Dissatisfied

with the results obtained, I this morning obtained Dr. Roget’s opinion,

which was favourable but uncertain; next Dr. Faraday’s, who, though

speaking positively as to the general results formerly, hesitated to

give an opinion as to the galvanic fluid action on a voltaic magnet

at a great distance when the question was put to him in that shape.

I next tried Clark, a practical mechanician, who spoke positively

in favour of my views, yet I felt less satisfied than ever, and

called upon a Mr. Wheatstone, Professor of Chemistry at the London

University, and repeated my inquiries. Imagine my satisfaction at

hearing from him that he had four miles of wire in readiness, and

imagine my dismay on hearing afterwards that he had been employed for

months in the construction of a telegraph, and had actually invented

two or three with the view of bringing them into practical use. We had

a long conference, and I am to see his arrangement of wire to-morrow

morning, &c.... The scientific men know little or nothing absolute on

the subject. Wheatstone is the only man near the mark.” Mr. Latimer

Clark accounts for the notice of Professor Wheatstone’s experiments

in the _Magazine of Popular Science_ for March, 1837, by saying that

it was “evidently inserted after the remainder of the articles had

been completed, and set in type,” and that Wheatstone supplied the

information after Mr. Cooke’s visit to him--a gratuitous assertion

which is not supported by any positive evidence. Then, again, Mr.

Latimer Clark, an eminent authority upon the laws of electricity,

says, concerning Mr. Cooke’s proposed telegraph, that “upon the whole

the instrument, the result of such long cogitation and experiment,

is disappointing, and one is not surprised at Wheatstone, with his

exquisite mechanical appreciation, criticising it as severely as he

did.” Moreover, he admits that the first telegraph instrument used

between Camden Town and Euston was Wheatstone’s.

Not less emphatic or explicit was the statement of the case given by

Professor Wheatstone himself, and moreover it contained some passages

of biographical interest. Addressing Mr. Cooke, he said: “You state

that you alone had succeeded in reducing to practical usefulness

the electric telegraph at the time you sought my assistance. This I

wholly deny. Your instrument had never been practically applied, and

was incapable of being so. Mine were all founded on principles which

I had previously proved by decisive experiments would produce the

required effects at great distances. Your statement that I employed

myself at your request in perfecting your invention in detail is

equally erroneous. My time, so far as it was devoted to telegraphic

researches, was exclusively occupied in perfecting my own instrument,

which had nothing in common with yours, and in which I was not only

known to be engaged by all my scientific friends, but which was even

announced in public print before I knew of your existence. I confined

myself to carrying out one of my own inventions for two reasons: First,

because my experiments led me to believe that the motions of a needle

could be produced at distances at which no effects of electro-magnetic

attraction could be obtained; and, secondly, I did not wish to

interfere with you. With regard to the subsequent development of my

first telegraph, the essential principles of which are the formation

of numerous circuits from a few wires and the indication of characters

by the convergence of needles, I am indebted to no person whatever; it

is in all its parts entirely and exclusively my own. The modifications

you introduced without consulting me in the instruments for the Great

Western Railway altered the simplicity and elegance of the arrangement

without the slightest advantage, and I certainly should not recognise

them in any published description.”

“The circumstances under which your name was allowed to take the lead

in the titles of the British patents have escaped your memory. I will

endeavour to recall them to you. When you first proposed partnership,

you know how strongly I opposed it, and on what grounds. I said I was

perfectly confident of being able to carry out my views to the end

I anticipated, that I fully intended doing so, and publishing the

results, then allowing any person to carry them into practical effect.

I told you that, while I admired the ingenuity of your contrivance

I deemed it inapplicable to the purpose proposed, and I urged that

in that case the association of my name with that of others would

diminish the credit I should obtain by separately publishing the result

of my researches. You replied that you were not seeking scientific

reputation, and therefore no difference could arise between us on

that account, and that your sole object was to carry the project into

profitable execution. A patent was arranged to be taken out in our

joint names which should include our two separate instruments. When

we met to settle the preliminaries for the English patent I was much

surprised to find your name inserted first, considering that, as we put

ourselves on an equality by each contributing an invention, to put my

well-known name after yours, then totally unknown, might be construed

into an admission of the superiority of your share. You urged that your

pecuniary obligations were the greater, and that as I intended to leave

negotiations with you, your authority might be less respected if your

name appeared second, and that your invention was the more valuable--an

assumption I did not admit, and the event proved I was right. But we

agreed that in subsequent patents the order should alternate. Some

time after we met to settle the Scotch patent draft, for which you

had prepared the declaration. I was again surprised to find the same

order of precedence repeated, and I objected to it as contrary to

our previous understanding. You said it had been done without your

knowledge, but objected to the alteration on the ground of delay. After

discussion we made a new arrangement, that on my allowing your name to

stand on the British patents, mine should take the lead in all foreign

ones. It was resolved afterwards that an American patent should be

obtained, and when I attended to sign the preliminary papers, I found

that again, without any notice to me, my name was made to follow yours.

I refused to sign the papers, and you then consented to keep your

word. The only reason you alleged was that your authority as manager

would be diminished if you appeared as second partner.

“When I had attained some complete results, I invited you to the

College to see them, and before describing or showing the new

experiments and instruments, I proposed conditions: That having, at

my own expense, undertaken a series of investigations which led to

important consequences greatly increasing the pecuniary value of the

patents, and having invented new instruments which, besides being

applicable to all the purposes for which the existing arrangements

could be applied, might also be profitably applied to other purposes to

which the previous instruments were not at all adapted, I required as a

compensation that I should retain the exclusive right of manufacturing

them and all instruments I should construct involving the same

principles, and also the privilege of employing them exclusively for

domestic and official purposes. To these conditions you assented, and

afterwards I showed you the completed instruments, and read to you a

list of the further experiments. You confirmed your assent. On this

occasion you breathed not a word respecting the claim since put forward

to be considered the joint inventor of my new instruments.

“You ask me to acknowledge that ‘I, having certain improvements on our

joint invention in progress depending fundamentally upon principles

first discovered and applied by you, had asked as a favour,’ &c. It

is unjust to urge such an acknowledgment upon me, and I state plainly

that nothing shall compel me to make it. My instruments are original

combinations involving a great number of points entirely new. With

equal justice Mr. Ronalds might call upon me to declare that he is

the joint inventor, because, like him, I use a revolving dial with

letters--or Professor Steinheil complain of my suppressing his name

because, in one of my most recent important modifications I employ,

as he has done, the magneto-electric machine--as you to put forth

that claim, because in some of my new instruments I have employed

magneto-electric attraction, which you had done before me in your

instrument; or with the same reason might Mr. Morse call upon me to

proclaim him to be joint inventor because he, independently of you, has

employed an electro-magnet to move machinery intended for a telegraph.

One of your complaints is, that in the notices of my experiments in

Belgium the employment of two wires for an electric telegraph was not

specifically mentioned as a discovery of yours. Such a claim on your

part has no foundation, for, without going further back, Ronalds’ two

telegraphs--two telegraphs on different principles, which I myself

proposed before I knew you,--and Steinheil’s telegraph, with which I

was acquainted before yours, had two wires. You forget that it is my

electric telegraph, and not yours, that is in daily use. And, lastly,

you forget that, had it not been for my exclusive attention to it since

I first conceived the idea, a practical telegraph might still have

remained an unaccomplished purpose.

“Do not, however, misunderstand me. Far be it from me to underrate your

exertions; they have been very great, and absolutely indispensable

to the success of our joint undertaking. Without your zeal and

perseverance and practical skill, what has been done would not have

been so readily effected; but on the other hand, I may say, that had

you entered the field without me, your zeal, perseverance, and money

would have been thrown away.”

His subsequent as well as his previous inventions afford the strongest

evidence of his originality. His inventions were not more distinguished

for ingenuity than for permanent usefulness, and they had this unusual

characteristic, that nearly every one of them became the parent of a

considerable offspring. These form his most enduring monument, and a

simple record of them forms his best vindication.

In 1840 he produced three inventions at one birth--his dial telegraph,

his printing telegraph, and his electric clock. Each of these

instruments was worked by utilising one of the great discoveries

previously made in electro-magnetism. It was known that when an

electric current is sent through a wire coiled round a piece of soft

iron, the iron becomes a magnet. If the current is stopped for a

moment, the iron instantly ceases to act as a magnet. When the piece

of iron is magnetic, it will attract another piece of iron, and as the

attraction ceases as soon as the current ceases, the iron can then by

means of a spring be made to resume its original position. Thus by

frequently interrupting an electric current, a piece of iron held in

its place by a small spring can be made to move to and fro as often as

it is attracted. Professor Wheatstone invented a method of regulating

the application of the current to such a magnet, and of converting the

to-and-fro motion of the iron into symbols. The piece of mechanism that

regulated the current was a wheel called a commutator or communicator;

around its circumference were twenty-four teeth; and each tooth was

made to act as a conductor of electricity in this way: Under the teeth

of the communicator there was a metallic circle which was connected

with the telegraph wire; and in this metallic circle twenty-four pieces

of wood were inserted at equal distances apart; so that the teeth of

the communicator, which was connected by wire with the battery, at one

moment touched the conducting metal of the circle underneath it, and

thus imparted a current to the telegraph wire, while at the next turn a

pace round they rested on the non-conducting wood, by which the current

was prevented from passing from the communicator wheel to the telegraph

wire. In a complete revolution of such a wheel the current would be

twenty-four times established and as often interrupted; and each of

these twenty-four alternations was made to indicate a letter of the

alphabet at the other end of the wire by means of a piece of mechanism

like a clock. When the current passed along the wire, it electrified

a magnet, which then drew towards it an armature (a piece of iron).

The movement of this armature (forward by electricity and backward

again by a spring) acted like a pendulum in moving a wheel, which in

turn moved a hand on a dial containing the letters of the alphabet.

Just as at each movement of the pendulum of a clock, a wheel moves

one tooth forward; so at each movement of the armature by an electric

current, a twenty-four toothed wheel was moved one tooth forward, and

at each such movement the hand on the dial moved from one letter of the

alphabet to the next one. If, for instance, the indicator hand stood at

A and it was desired to transmit E, this would be done by moving the

communicator wheel four teeth onward; in doing that four successive

currents would be transmitted to the indicator, the hand of which would

consequently move over B, C, D, and then reach E, where a pause would

indicate that this was the letter intended to be read. This was called

Wheatstone’s electro-magnetic telegraph, because it was worked by an

electric current from a battery electrifying a magnet.

In 1841 he invented a machine in which magnets produced electricity

sufficient to work the telegraph. Hence it was called a

magneto-electric machine, and the telegraph worked by it was

called a magneto-electric telegraph. In 1840 he explained that

magneto-electricity was of momentary duration as contrasted with the

continuous action of electro-magnetism. The magneto-electric machine

then in use consisted of a coil or coils of insulated wire being

made to revolve in the vicinity of a magnet, or the magnet revolving

in the vicinity of the insulated coils of wire, and this apparatus

only produced a series of shocks, or instantaneous as compared with

continuous currents. His new invention combined several of these

machines into one by so uniting their coils as to form one continuous

circuit, thereby producing the same effect as a perfectly continuous

current. He said this magneto-electric machine could be used for many

purposes for which a voltaic battery had been employed. The patent for

it was taken out in his own name.

Meanwhile another competitor had begun to challenge his originality.

On November 26, 1840, Professor Wheatstone read a paper before the

Royal Society describing his electro-magnetic telegraph clock as his

own invention. He also showed the clock in action in the library.

In January following he received notice from a Mr. Barwise, of St.

Martin’s Lane, that he claimed to be the inventor of the clock, and

shortly afterward it was stated in placards that Messrs. Barwise and

Bain were the joint inventors. At first Professor Wheatstone took

little notice of the attacks thus made upon his originality, but in

June, 1842, he was directly charged by Mr. Bain in the public press

with appropriating his inventions. In reply to that accusation,

Professor Wheatstone stated that Alexander Bain was a working mechanic

who had been employed by him between the months of August and December,

1840; and to the allegation that Bain communicated the invention

of the clock to him in August, 1840, he answered that there was no

essential difference between his telegraph clock and one of the forms

of his electro-magnetic telegraph, which he had patented in January,

1840; that the former was one of the numerous and obvious applications

which he had made of the principle of the telegraph, and that it only

required the idea of telegraphing time to present itself and any

workman of ordinary skill could put it in practice--in telegraphing

messages the wheel for making and breaking the circuit was turned

round by the finger of the operator, while in telegraphing time it

was carried round by the arbor of a clock. He also stated that, long

before the date specified, he mentioned to many of his friends how

the principle of his telegraph could be applied “to enable the time

of a single clock to be shown simultaneously in all the rooms of a

house, or in all the houses of a town connected together by wires.”

The accuracy of these statements was verified by Dr. W. A. Miller,

of King’s College, and by Mr. John Martin, the eminent artist. The

latter stated that Professor Wheatstone explained to him in May, 1840,

his proposed application of his electric telegraph for the purpose of

showing the time of a distant clock simultaneously in as many places

as might be required. Mr. Martin, on hearing the explanation, said to

him, “You propose to lay on time through the streets of London as we

now lay on water.” Mr. F. O. Ward, a former student of King’s College,

stated that Professor Wheatstone explained the matter to him on June

20, 1840. While watching the motions of the dial telegraph as he turned

the wheel that made and broke the circuit, Mr. Ward remarked that if

it were turned round at a uniform rate, the signals of the telegraph

would indicate time, to which Professor Wheatstone replied: “Of course

they would, and I have arranged a modification of the telegraphic

apparatus by which one clock may be made to show time in a great many

places simultaneously;” and the Professor showed him drawings of an

apparatus for that purpose, in which the making and breaking of the

circuit by the alternate motion of the pendulum of a clock, would

produce isochronous signals on any number of dials, provided they were

connected by wire. The electric clock in question has been repeatedly

tried, but has not answered expectations.

Mr. Alexander Bain also accused Professor Wheatstone of appropriating

his printing telegraph. He said he communicated the invention of

the electric clock, together with that of the electro-magnetic

printing telegraph, to Professor Wheatstone in August, 1840, before

ever Professor Wheatstone did anything in the matter. To that the

Professor replied that the printing apparatus was merely an addition

to the electro-magnetic telegraph, of which he was undoubtedly the

inventor. As to the way in which this telegraph printed the letters,

he explained that for the paper disc (or dial) of the telegraph, on

the circumference of which the letters were printed, he substituted

a thin disc of brass, cut from the circumference to the centre so as

to form twenty-four radiating arms on the extremities of which types

were fixed. This type-wheel could be brought to any desired position

by turning the commutator wheel. The additional parts consisted of a

mechanism which, when moved by an electro-magnet caused a hammer to

strike the desired type--brought opposite to it--against a cylinder,

round which were rolled several sheets of thin white paper along with

the alternate blackened paper used in manifold writing. By this means

he obtained at once several distinct printed copies of the message

transmitted. He maintained that the plan was begun and carried out

solely by himself; and Mr. Edward Cowper stated, as corroborative

evidence, that on June 10, 1840, he sent a note to Professor Wheatstone

(who had previously told him of the contrivance by which his telegraph

could be made to print), giving him information, which he had asked

for, respecting the mode of preparing manifold writing paper, and the

best form of type for printing on it.

It was also at the beginning of 1840 that he invented the

“chronoscope,” an instrument for measuring the duration of small

intervals of time. It was used for measuring the velocity of

projectiles, and consisted of a clock movement set free at the moment a

ball was discharged from a gun, and stopped when the ball reached the

target. For this purpose a wire in an electric circuit at the gun’s

mouth was broken at the instant the ball passed out of the gun; and the

circuit was completed when the ball reached the target, the circuit

acting on the clock movement by means of an electro-magnet. It was

publicly stated in 1841 by independent witnesses that the chronoscope

was capable of indicating the one 7300th part of a second; and the

inventor himself stated in 1845 that with it the law of accelerated

velocities had been obtained with mathematical rigour, that with it he

could measure the fall of a ball from the height of an inch, and that

by different arrangements which he had adopted to render the instrument

applicable to different series of experiments, he intended to employ it

for measuring the velocity of sound through air, water, and masses of

rock, with an approximation that had never been obtained before.

In 1843 he brought before the Royal Society several methods of

measuring the force of an electric current, and the paper he then read,

and the methods he described, were for many years unrivalled both for

simplicity and ingenuity. Speaking of electricity as an energetic

source of light, of heat, of chemical action, and of mechanical

power--prescient words in those days--he said it was only necessary

to know the conditions under which its various effects may be most

economically and energetically manifested to enable us to determine

whether the high expectations formed in many quarters of some of its

daily increasing practical applications are founded on reasonable

hope or on fallacious conjecture. He considered that they had ample

theory, but not enough of experiment to supply, except in a few cases,

the numerical value of the constants which enter into various voltaic

circuits; and without that knowledge accurate conclusions could not be

arrived at. He explained that electro-motive force (E.M.F.) meant the

cause which in a closed circuit originated an electric current; that

by resistance was signified the obstacle opposed to the passage of

the electric current by the bodies through which it passed; and that

resistance was the inverse of what is usually called their conducting

power. The principle of his methods was the use of variable instead

of constant resistances, bringing thereby the currents compared to

equality, and inferring from the amount of the resistances measured out

between two deviations of the needle the electro-motive force and the

resistances of a circuit, according to the particular conditions of

the experiment. If a needle be connected with two coils of wire, and

if a current be sent through one coil, the needle will be deflected

to one side. If at the same time a current of the same strength

be sent through the other coil, the currents will neutralize each

other and the needle will remain at rest. This is what is called a

differential galvanometer, and when two currents of different strength

are sent through it simultaneously the needle is only affected by

their difference. One form in which Professor Wheatstone used this

principle has ever since been known as “the Wheatstone bridge.” It is

a method by which pieces of wire of known resistance are interposed in

a circuit until the current in the wire to be tested counter-balances

that of the wire used as a standard of resistance; when that happens

the needle indicator stands still, the wire to be tested being now

of the same resistance as that of the known standard. Professor

Wheatstone perceived that it was of the highest importance to have a

correct standard of resistance, and one that could be easily reproduced

for the purpose of comparison. He therefore adopted as a unit of

resistance a copper wire one foot in length, 100 grains in weight, and

·071 of an inch in diameter. He was the first man who made a unit of

resistance, and who introduced into electrical science the name of a

unit and multiples of a unit; and when, nearly a quarter of a century

afterward, the British Association appointed a committee on electrical

standards, their reports describing about a dozen standards, paid a

tribute to the originality of Professor Wheatstone as the introducer

of the first unit. He was not, however, the first to use the method of

measuring electrical currents or the resistance of wires, since known

as the Wheatstone Bridge. In a note appended to his paper read before

the Royal Society in 1843 he stated that Mr. Christie had described

the same principle in the _Philosophical Transactions_ for 1833, and

added that “to Mr. Christie must therefore be attributed the first

idea of this useful and accurate method of measuring resistances.”

Mr. Christie, who was connected with the Royal Military Academy at

Woolwich, said in his paper that the arrangement he proposed possessed

many advantages; it afforded a very accurate measure of the difference

of intensities of two electric currents, whether they were from

the same source and were merely modified by circumstances, or had

different sources; and it afforded likewise a very accurate measure

of the conducting powers of different substances. Mr. Christie did

not, however, succeed in drawing attention to this method, and it lay

unheeded till Professor Wheatstone revived it and expounded it with

matchless clearness. He at the same time devised an instrument called

the Rheostat, in which a highly resisting wire was so wound round the

surface of a cylinder that any length of it could be connected with a

circuit by merely turning round the handle of the cylinder till the

needle or galvanometer connected with it showed that the resistance of

the wire on the cylinder was equal to that of the wire to be tested.

As the resistance of the wire on the cylinder was accurately known

beforehand, the length of it required to counterbalance the resistance

of the wire in course of being tested became the measure of the latter.

The wire on the cylinder may be compared to a winding measuring line;

only being of high resisting power, a short length of it suffices to

measure a long wire of low resistance.

Professor Wheatstone told the Royal Society in 1843 that he had

employed the Rheostat and differential resistance measurer (the

Wheatstone Bridge) for several years previously for the purpose of

investigating the nature of electrical currents--a statement which had

received a singularly generous corroboration; for in 1840 Professor

Jacobi told the British Association meeting in Glasgow that Professor

Wheatstone had shown him in London an instrument for regulating a

galvanic current, similar in principle to one that he had laid before

the St. Petersburg Academy of Sciences at the beginning of that

year. Professor Jacobi, in stating that it was quite impossible that

Professor Wheatstone could have had any knowledge of his similar

instrument, said he must add that while he had only used his instrument

for regulating the force of currents, Professor Wheatstone had founded

upon it a new method of measuring those currents and of determining the

different elements of them.

The Royal Society, which in 1840 had presented him with a royal medal

“for the ingenious method by which he had solved the difficult question

of binocular vision,” presented him with another medal in 1843, when

the President, the Marquis of Northampton, said: “I now present you

with this medal, one of those intrusted to the President and Council

of the Royal Society by Her Most Gracious Majesty, for your paper

entitled, ‘An account of several new Instruments and Processes for

determining the Constants of the Voltaic Circuit.’ This is not the

first time that I have had the pleasing task of acknowledging on the

part of the Royal Society the great ingenuity as well as knowledge that

you bring to the increase of science. You not only add to our store of

knowledge, but you give to others the means of doing so too. You not

only set the example of scientific pursuit, but you also facilitate it

in those who may become at once your followers and your rivals. In the

particular case before us you have introduced accuracy where even rough

numerical data were almost wholly wanting. The improvement of such

facilities in any branch of science can hardly be overstated.”

In 1845 a patent was taken out for a new form of needle telegraph,

respecting the origin of which Mr. Latimer Clark relates the following

incident as told to him by Mr. Greener some fifteen years after it

occurred. A very high tide which occurred in 1841 caused an inundation

of the Blackwall Railway, and injured the piping in which were inclosed

the seven or eight wires then in use--they were then using a wire to

each station; so that only one wire or two could be worked. Mr. Cooke,

who was the practical engineer of the telegraph, was much concerned

lest some accident might happen through the failure of the telegraph,

whereby they would, he feared, be unable to communicate with the

intermediate stations from the Blackwall end of the line. In view of

this contingency Mr. Greener and another clerk arranged a code of

signals which could be worked on one wire by simply deflecting the

needle alternately, once, twice, or thrice, to the right or left; and

in this way they managed to carry on communications respecting their

dinners and other private matters. “Mr. Cooke, on being informed that

it was still possible to telegraph, gladly availed himself of the new

means of communication by one wire, and from that moment our well-known

single and double-needle instrument was practically invented. If these

statements be accurate the first idea of the double-needle telegraph

did not originate either with Wheatstone or Cooke, but was suggested by

Mr. Greener and his partner, who was at this time engaged with him on

the Blackwall telegraph.”

In the popular accounts of great discoveries or inventions it is

generally the falling of an apple that is said to suggest to a Newton

the law of gravitation, or it is the boiling of a tea-kettle that

suggests to a Watt the mechanism of the steam-engine. This has become

the orthodox way of accounting for the triumphs of mind over matter in

order to make them acceptable to intellectual mediocrity. Indeed, the

Abbé Raynal says that the only difference between a genius and one of

common capacity is that the former anticipates and explores what the

latter accidentally hits upon. But, he adds, “even the man of genius

himself more frequently employs the advantages that chance presents

to him; it is the lapidary that gives value to the diamond which the

peasant has dug up without knowing its worth.” Now it is a curious

fact that while the needle telegraph was one of the few telegraphic

inventions of Professor Wheatstone that was undisputed during his

lifetime, the preceding account of its origin was never publicly

mentioned till after his death.

Facts, however, are against its accuracy. The high tide referred to

in the story occurred on November 18th, 1841, after the five-needle

telegraph had been in operation on the Great Western Railway more

than two years; and a few weeks’ experience of its working enabled a

clerk of ordinary intelligence to tell the letters transmitted by the

movement of the needles, even if the printed letters on the dial to

which the needles pointed were covered over or obliterated. A minute’s

examination of the five-needle instrument shows that a different

combination of movements is required to represent each letter, and if

these combinations be learned by a few weeks’ practice, or be written

down on paper, they constitute a complete alphabet of signs. And that

alphabet of signs which the five-needle instrument first taught could

obviously be produced by a single needle. Thus on the five-needle

instrument A is represented by the movement of the first needle to

the right, and the fourth from it to the left; but it would also

be represented by the movement of one needle first to the right and

then four times to the left. In like manner B is represented on the

five-needle instrument by the first needle moving to the right and

the third from it to the left. By means of a single needle it could

be represented by one movement to the right and three to the left;

and so on with the other letters. Experience has suggested that the

alphabet could be represented by fewer movements than those practically

exhibited by the five-needle instrument; but it is obvious that a few

weeks’ working of the five-needle instrument--and not a flood in the

Thames--was sufficient to show that the movements of needles, without

a dial or a printed alphabet, could be made to convey intelligence.

This is no mere speculation. More than this was in actual operation

on the Blackwall Railway; for in a contemporaneous account it is

stated that the wires run all along the line inclosed in a metal

tube, and the arrangement is such that whenever a particular index

deviates to the right or left at the Minories Station, an index

deviates to the right or left at all the other stations at the same

instant. “If then,” says the contemporary writer, “a preconcerted

alphabet, or key, or dictionary, or table of signals be agreed on, the

relative positions of two or more index-hands will serve to convey a

message. By the side of the telegraphic case a large chart is hung

up, containing about a hundred sentences, instructions or questions,

each of which is symbolled by a particular position of two or three

index hands. Thus one position, capable of being effected by two

movements of the handles, implies, ‘Will the next train wait for the

next steam-boat?’ Another implies, ‘Will the steam-boat wait for the

next train?’ And others: ‘How many passengers?’ ‘How many carriages?’

and various inquiries and directions relating to the engines, the

ropes, the telegraphs, and the steam-boats which start from and

arrive at Blackwall.” The writer added that by employing the combined

simultaneous motion of three or four needles, the five-wire telegraph

would afford nearly 200 signals, besides those appropriated to the

alphabetic characters.

It thus appears that the idea of making the deviations of a needle

represent messages or letters was not only obvious but in daily

use. Yet the erroneous traditions that already envelop the infancy

of this telegraph do not end here. The contemporaneous account just

quoted concludes with the remark that a telegraph like that used on

the Blackwall Railway and the Great Western Railway, if consisting

merely of three needles and giving only twelve signs, has a power

of combination fully equal to the semaphore then in use; and in

recent years it has been represented by persons of authority in

the telegraph world that the double-needle instrument formed the

transition stage from five needles to one. Hence the single-needle

instrument has generally been regarded as a gradual improvement of

the parent instrument of five needles. But the fact is that both the

single and double-needle instrument were minutely described in one and

the same patent taken out in 1845. In that description, which would

fill a chapter of this book, Professor Wheatstone was more careful

to explain the advantages of the single than of the double-needle

instrument. He expressly disclaimed any intention to lay down a

particular signification to the signals by which the alphabet could

be represented; he merely gave illustrations to show how easily a

sufficient variety of signals could be obtained. At the same time he

gave an alphabet of signs suitable for a single-needle instrument,

and although experience has suggested a more convenient combination

of signals, it is on record that within a year or two after the

patent for the single and double-needle telegraphs was taken out, the

single-needle instrument was tried on some of the railway lines, and

the alphabet of signals used was that which the five needle instrument

suggested, with slight modifications. The single needle, however, was

considered deficient in rapidity; and consequently to obtain greater

speed the double-needle instrument was preferred. One of the first

lines to adopt it was the South Western; it soon came to be regarded as

the most rapid means of telegraphing; and hence it came into general

use. It maintained its supremacy in England till more expeditious

instruments were invented, and then it was gradually superseded by

the single-needle instrument, which was found to be more accurate

and economical. Now the single-needle instrument may be seen at most

railway stations and rural post offices in the United Kingdom. In this

instrument the needle when moved by a current to the right hand or the

left, strikes against a projecting pin placed on each side to arrest

its motion; the sender by moving a handle can deflect the needle at

will either to the right or the left; one deflection to the left and

one to the right represents A; one to the right and three to the left

B; one to the right, one to the left, another one to the right and

another to the left C; one to the right and two to the left D; and so

on. None of the twenty-four letters of the alphabet has more than four

deflections. While E has one to the left, I has two, S three, and H

four. T has one to the right, M two, O three, and Ch. four.

It was calculated that about 15,000 of these instruments were in use in

Great Britain in 1885.

Meanwhile another improvement of a permanent nature had taken place.

The use of the earth instead of a special wire as the return circuit

was first adopted in England on the Blackwall Railway telegraph in

1841, and on the Manchester and Leeds line in 1843. The history of this

improvement is curious. In 1838 Professor Steinheil used the earth to

complete the circuit of an electric telegraph which he established at

Munich, and he has generally been regarded as the first electrician who

purposely did so. But William Watson discovered the same thing in 1747.

He erected a wire fully two miles long over Shooter’s Hill, supporting

it upon rods of wood. When electricity was communicated to the wire

at one end, the shock at the other end appeared to be instantaneous,

and the electricity was then communicated to the earth by means of a

rod of iron. It is also on record that in 1756 Kennersley, of Boston,

suggested to the celebrated Franklin that “as water is a conductor as

well as metals, it is to be considered whether a river or a lake, or

sea may not be made part of the circuit through which the electric fire

passes instead of a circuit all of wire.”

This expedient, though now considered essential to the successful

working of a telegraph, was not practically adopted till nearly a

century afterwards, when it was found that as soon as the electricity

had done its work the best thing to do with it was to convey it into

the earth, for just as the flow of rivers is accelerated by their

waters falling into the sea, so electric conduction is greatly improved

by establishing a good connection between the end of a telegraph

wire and the earth. Thus it was found in 1841 that by leading the

electricity to the earth, after it had done its work at the telegraphic

apparatus, the wire which had been previously used to bring it back,

or to complete the circuit, could be dispensed with, that by the earth

thus absorbing the electricity its transmission along the wire was

greatly facilitated, and that it could be transmitted to a greater

distance and through a smaller wire.

CHAPTER III.

“In conducting the petty affairs of life, common sense

is certainly a more useful quality than genius itself.

Genius, indeed, or that fine enthusiasm which carries the

mind into its highest sphere, is clogged and impeded in

its ascent by the ordinary occupations of the world, and

seldom regains its natural liberty and pristine vigour

except in solitude. Minds anxious to reach the regions

of philosophy and science have indeed no other means

of rescuing themselves from the burden and thraldom of

worldly affairs.”--ZIMMERMAN.

The invention of electrical apparatus had reached a stage of progress

in 1841 sufficiently advanced to make the telegraph a practical

success. What was next wanted was the general adoption of the telegraph

by the public, and this was the task which exercised the business

energy of Mr. Cooke. It was fortunate that the dispute between

Professor Wheatstone and Mr. Cooke as to the origin of the telegraph

did not interfere with their efforts to promote its extension. Like

most new inventions, it had to fight its way at first. In 1841 Mr.

Cooke wrote a small book on _Telegraphic Railways; or the Single Way_,

in which he contended that the whole system of double way, time tables,

and signals of railways was a vain attempt to attain indirectly and

very imperfectly, at any cost, that safety from collision which would

be perfectly and cheaply conferred by the electric telegraph. It was

well known, he said, that on the Blackwall Railway “the carriages on

each line are moved by what is called ‘a tail rope,’ to which they are

attached and which is almost incessantly being drawn along the line to

be wound up on a drum at one terminus or the other, by the alternate

action of the stationary engines. It is consequently necessary that

before the engineman applies the power of his engine to the rope for

the purpose of giving motion to a train, he should receive a specific

intimation from every other station that its carriage is attached to

the rope ready to start; otherwise an independent and uncontrolled

motive power acting from the terminus would frequently cause dreadful

collisions among carriages placed at stations so nearly adjacent as

those of Shadwell, Stepney, Limehouse, the West India Docks, and

Poplar.” But such a matter of fact illustration was not enough for Mr.

Cooke to give; so after dilating on the good the telegraph was likely

to do as the handmaid of the railway, he concluded by saying that

“as the basis of an essentially new system of railway communication,

at once safe, economical, and efficient, the electric telegraph may

diffuse its blessings of rapid intercourse to districts which could

never otherwise enjoy them. It may increase the revenues of the

greatest lines by adding to them fresh sources of lateral traffic; it

may permanently raise the price of shares by opening important lines

now destitute of the means of completion; and reduce indefinitely

the expense of travelling on lines yet to be made. Above all it may

accomplish the otherwise scarcely attainable union by railway between

England and Scotland, and perhaps realise the patriotic aspirations

of those who see in an extended system of railways employing her

population and developing her resources, a restoration of tranquillity

to Ireland.” No wonder that Professor Wheatstone appreciated Mr.

Cooke’s “zeal and perseverance,” not to speak of his imagination. But

all these were insufficient. Throughout the year 1842 a prominent

advertisement in the _Railway Times_ invited the attention of railway

companies, engineers, and other parties requiring a certain and

instantaneous mode of communicating intelligence between distant

points, to Messrs. Cooke and Wheatstone’s electric telegraph, an

invention which, “besides its superiority for general telegraphic

purposes, in point of expedition, secrecy, night action, and

preliminary warning, is peculiarly adapted to the use of railways,” and

“is also well adapted for mines, coal pits, docks, &c.”

At the same time the general public were being invited to witness

its performances as the latest and greatest sensation in London. One

announcement issued in 1842 stated that “under the special patronage

of Her Majesty and H. R. H. Prince Albert, the public are respectfully

informed that this interesting and extraordinary apparatus, by which

upwards of fifty signals can be transmitted 280,000 miles in one

minute, may be seen in operation daily (Sundays excepted) from 9 A.M.

till 8 P.M. at the telegraph office, Paddington, and telegraph cottage,

Slough. Admission 1_s._”

Those who were among the first to respond to this tempting invitation

must have marvelled at the littleness of the apparatus capable of doing

such wonderful work. It was inclosed in a mahogany case a little larger

than a hat-box, which stood upon a table; it was worked by pressing

small brass keys, similar to those on a keyed bugle, and spectators

were informed that these keys acting, by means of electric power, upon

various hands placed upon a dial plate at the other end of the line

made them point not only to each letter of the alphabet as each key

was struck or pressed, but when desired to numerals and to points of

punctuation, such as a comma, colon, &c. When any mistake was made in

transmitting a message, and a certain key was struck in consequence,

it made the hand point to an X, which indicated that an “erasure” was

intended.

Ere long its utility was shown to be greater than its novelty. As it

continued in good working order, events occurred which demonstrated

its value. For instance, it transmitted the following messages which

effected results that excited public interest at the time:--

Eton Montem, August 28th, 1844.--The Commissioners of Police have

issued orders that several officers of the detective force shall be

stationed at Paddington to watch the movements of suspicious persons

going by the down-train, and give notice by the electric telegraph to

the Slough station of the number of such suspected persons and dress,

their names if known, also the carriages in which they are.

Paddington, 10.20 A.M.--Mail train just started. It contains three

thieves, named Sparrow, Burrell, and Spurgeon, in the first compartment

of the fourth first-class carriage.

Slough, 10.48 A.M.--Mail train arrived. The officers have cautioned the

three thieves.

Paddington, 10.50 A.M.--Special train just left. It contained two

thieves: one named Oliver Martin, who is dressed in black, crape on his

hat. The other, named Fiddler Dick, in black trousers and light blouse.

Both in the third compartment of the first second-class carriage.

Slough, 11.16 A.M.--Special train arrived. Officers have taken the two

thieves into custody, a lady having lost her bag containing a purse

with two sovereigns and some silver in it; one of the sovereigns was

sworn to by the lady as having been her property. It was found in

Fiddler Dick’s watch-fob.

Slough, 11.51 A.M.--Several of the suspected persons who came by

the various down trains are lurking about Slough, uttering bitter

invectives against the telegraph. Not one of those cautioned has

ventured to proceed to the Montem.

It was afterwards reported that when the train arrived at Slough a

policeman, opening the door of the carriage described in the telegram,

asked if any passenger had missed anything. On search being made by the

astonished passengers, one of them, the lady, exclaimed that her purse

was gone. “Then you are wanted, Fiddler Dick,” said the constable to

the thief, who appeared thunderstruck at the supernatural discovery.

Fiddler Dick surrendered himself, and delivered up the stolen money. It

was said that after that the light-fingered gentry avoided “the wire.”

Another placard which was distributed all over London informed the

public that “the telegraph, Great Western Railway, may be seen in

constant operation daily, Sundays excepted; by this powerful agency

murderers have been apprehended, thieves detected, and, lastly (which

is of no little importance), the timely assistance of medical men has

been procured in cases which would otherwise have proved fatal.”

Yet something more than sensational placards was necessary to impress

upon the public mind the utility of the telegraph. “The genius of the

English people,” says Smollett, “is perhaps incompatible with a state

of perfect tranquillity: if it is not ruffled by foreign provocations

or agitated by unpopular measures of domestic administration, it will

undergo fermentations from the turbulent ingredients inherent in its

own constitution: tumults are excited and faction kindled into rage by

incidents of the most frivolous nature.” He goes on to say that in 1753

the metropolis of England was divided and discomposed in a surprising

manner by a dispute in itself of so little consequence to the community

that it did not deserve a place in a general history if it did not

serve to convey a characteristic idea of the English nation. In like

manner an incident occurred in 1845 which would not deserve a place

here, if it had not been the means of directing public attention to the

value of the telegraph. When the first telegraph was started in 1837,

England was absorbed in the turmoil of a general election; and all the

efforts made for the next eight years to excite public interest in its

favour were of little avail, till on the evening of January 2nd, 1845,

it played a notable part in effecting the apprehension of a notorious

murderer.

Between six and seven o’clock in the evening of that day, a woman named

Sarah Hart was murdered at Salt Hill, and a man was seen hurrying from

her house in a way that aroused suspicion. The police ascertained that

the murdered woman was kept by a Quaker named John Tawell, living at

Berkhampstead, who was in comfortable circumstances and respected in

the neighbourhood. He answered the description of the man seen near the

scene of the murder, and was believed to have hurried to Slough Station

and taken the train thence to Paddington. The police accordingly

telegraphed to Paddington as follows:

“A murder has just been committed at Salt Hill, and the suspected

murderer was seen to take a first-class ticket for London by the train

which left Slough at 7h. 42m. P.M. He is in the garb of a Quaker with a

brown coat on, which reaches nearly down to his feet; he is in the last

compartment of the second first-class carriage.”

The distance from Slough to Paddington being only seventeen miles,

there was not much time for telegraphing, and a circumstance occurred

which is said to have imperilled the transmission of the message. It

was transmitted on one of Wheatstone’s five-needle instruments, which

was afterwards preserved by the Post Office authorities on account of

the important part it played on this occasion. Among the letters of the

alphabet stamped on its diamond-shaped face, there was no “Q;” and when

the telegraph clerk at Paddington saw, in the middle of the message,

the needles pointing to the letters K-w-a he thought there must be

some mistake or fault, as no English word began with these letters.

He therefore asked the clerk at Slough to repeat the word, and again

came the letters K-w-a. Another repetition threw no fresh light on the

difficulty; and it is said that after several repetitions a sharp boy

suggested that the sender should be allowed to finish the word. This

being done the word came K-w-a-k-e-r, which the clerk recognised as

meaning Quaker. Notwithstanding the delay thus caused by the absence

of Q, the message was delivered in time, and after a short interval

the following reply to it was received: “The up train has arrived,

and the person answering in every respect the description given by

telegraph came out of the compartment mentioned. I pointed the man out

to Sergeant Williams. The man got into a New Road omnibus, and Sergeant

Williams into the same.” On arriving at Paddington, Tawell endeavoured

to elude observation, but unawares he was watched by the police as he

went to a coffee tavern in the City, where he was arrested next day

by order of the authorities. He was afterwards tried and convicted of

the murder, which was effected by administering prussic acid. In a

written confession left after his execution, Tawell said he had made

a previous unsuccessful attempt at murder, as he lived in perpetual

dread of his connection with Mrs. Hart becoming known to his wife. The

account given of his previous life also tended to increase the public

excitement. After a career of concealed profligacy, he was sentenced to

transportation in 1820 for forgery, but in Australia his intelligence

and good conduct induced the authorities to grant him first a ticket

of leave, and then emancipation. Eventually he became successful in

business as a chemist in Sydney, and at the end of fifteen years left

Sydney a rich man. Returning to England, he married as his second wife

a Quaker lady, who was thereupon expelled from the Society of Friends,

and who lived to see him executed for a crime which startled the whole

country, and for which the telegraph was accredited with effecting his

arrest.

Another instance of telegraphic speed created both astonishment and

amusement in 1845. In a contemporary publication it was reported that

“by the use of the telegraph has been accomplished the apparent paradox

of sending a message in the year 1845 and receiving it in 1844. Thus,

directly after the clock had struck twelve on the night of December 31,

the superintendent at Paddington signalled to his brother at Slough

that he wished him a happy new year. An answer was immediately returned

suggesting that the wish was premature, as the new year had not yet

arrived at Slough!”

In April following a passenger, while proceeding from Paddington by the

Great Western Railway, discovered that he had lost his purse containing

notes and cash to the amount of nearly 1000_l._ Alighting at Slough in

a state of great agitation, he telegraphed inquiries to Paddington, and

was quickly relieved of his load of distress by learning that he had

left his purse on the counter there, and that it was safe in the hands

of the clerk.

In 1845, too, it was thought a telegraphic achievement worth

proclaiming, that the entire report of a railway meeting was

transmitted in less than half an hour from Portsmouth to London; and

that in the spring of 1845 the Queen’s Speech, containing 3600 letters,

was transmitted from London to Southampton. This line of ninety miles

was then the longest in England. Prior to that the old semaphore system

was worked between London and Portsmouth. It consisted in the movement

in a preconcerted manner of elevated boards, fans, or shutters, in

a way that was visible from one station to another, it being agreed

that each particular movement should represent a letter, a word, or a

sentence. These semaphore stations had to be on elevated spots so as to

be visible to each other; but as the weather often obscured the view,

this means of communication was only available during one-fifth of the

year. Moreover, it cost 3,000_l._ a year to work it, and it was worked

for the last time on December 31, 1847. For the use of the new electric

telegraph to Portsmouth the Government paid 1,500_l._ a year; and to

preserve secrecy they had an alphabet of signals of their own, which

could only be read and worked by their own trusted servants.

As the line was also used for the transmission of public messages, it

may be noted that the charge for sending a message then was from 3_s._

to 9_s._ to Southampton, according to the number of words. By this

South Western telegraph a game of chess was played in April, 1845,

between Mr. Staunton and Captain Kennedy at the Portsmouth terminus,

and Mr. Walker and another gentleman at the Vauxhall terminus. Details

of the game were published in the press, and it was said that “the

electric messenger” had travelled 10,000 miles in course of the game.

Such were the infantine achievements of an agency which in less than

forty years was to transmit about 200 million messages per annum, and

was to connect the most distant parts of the civilised world.

Although the telegraph made little progress in England during the five

years that followed the construction of the line between Paddington and

Slough, the capture of Tawell, the Quaker murderer, followed by reports

of such incidents as those related above, gave such an impetus to its

extension that eighteen months after that event nearly 1000 miles

were constructed; and it was thought in those primitive times worth

recording that no less than 300 tons of wire, and 5000 loads of timber

had been used in telegraph works.

The year of 1847 was a time of great activity in telegraphic

construction. It was not till then that the London and North Western

Railway Company, on whose line the first working telegraph ever made

was tried, decisively adopted it--just ten years after the first

experiment. In 1847 the Company considered the commercial advantages

of the telegraph to be established beyond doubt, and they arranged for

its construction along their entire line. The Midland Company followed

their example.

The South Eastern Railway Company, which adopted the telegraph in 1845,

had a line 132 miles long in 1846, and that line was then the longest

in existence. On September 1, 1846, that railway company announced

that messages of twenty words would be sent for the public on payment

of 1½_d._ per mile. The minimum charge was 5_s._; and the cost of

sending a message from London to Ramsgate was 12_s._ 6_d._ Mr. C. V.

Walker, who had charge of the line, afterwards stated that the cost

of telegraphing was fixed at a Parliamentary fare and a half, because

it was suggested by “an authority” that it would not do to make the

telegraph rates too low, lest they might reduce the traffic receipts

of the Company by inducing passengers to use the wire instead of the

trains. That this was no mere fancy appears from a letter published in

a respectable weekly journal in September, 1846. The writer of that

letter complained that the directors had set such high prices upon

telegraphic communications as would entirely prevent their use, and

that they would thus by their covetousness defeat their own purpose

and interests. Five shillings for a message of less than twenty words

to Tonbridge; 7_s._ 6_d._ to Maidstone; 10_s._ 6_d._ to Canterbury

and Folkestone; 11_s._ to Dover, and 12_s._ 6_d._ to Ramsgate--who,

he asked, would pay “such a price for a few words’ conveyance when he

can send a sheet of foolscap fully written by the post for one penny;

or when for the amount they charge he can run there and back in the

Company’s own trains, and see his friends or correspond _vis à vis_,

with a ride into the bargain. How different is this from the charges on

the Continent! The telegraph on the Brussels and Antwerp line is open,

and the charge is 50 cents (about 5_d._).”

Events were already in progress which were destined to provide a

remedy for such primeval arrangements. On October 1, 1845, Mr. Cooke

was introduced to Mr. John Ricardo, M.P., who was so impressed with

the value of the telegraph that within three weeks he accepted the

terms upon which Mr. Cooke offered to sell it. Mr. Ricardo then

became chairman of the newly formed Electric Telegraph Company, which

obtained an Act of Parliament in June, 1846. The Company having been

thus empowered to acquire and work the telegraphs, gave £140,000 for

the patents of Messrs. Wheatstone and Cooke. Professor Wheatstone told

some of his friends that when the first patent was taken out for his

telegraph he had not the means to pay the cost of it, and hence he had

to get the support of others. Nine years afterwards when the patents

were sold for £140,000, only £30,000 of that sum went into his pocket,

though the original agreement was that he should be “on a footing of

equality” with Mr. Cooke as to participation in profits. It was Mr.

Cooke who negotiated the sale of the patents.

From a financial point of view the Company at the outset was not

prosperous, but under their management the telegraph was rapidly

extended; indeed its extension for a time appeared to exceed the public

requirements; and Mr. Ricardo had to advance money to pull them through

their difficulties. It was stated in 1847 that there were then twenty

lines of telegraph in England, while in Scotland, where in 1841 Sir

Charles Fox ordered a line to be made on the Glasgow and Cowlairs

Railway, there were now three lines. The total length of the lines laid

in 1847 was 1,250 miles; but as most of the lines had three or four

wires the total length of wire in operation was 6,017 miles. There were

253 stations, and nearly 400 instruments in use. In 1849 the Company

completed arrangements with the Post-master General and the different

lines of railway for further extensions of telegraphic lines from

their office at the General Post Office, St. Martin’s-le-Grand, to

most of the large towns in England and Scotland, to which messages of

twenty words could be sent for 1_d._ per mile for the first 50 miles,

½_d._ for the second 50 miles, and ¼_d._ for any distance beyond 100

miles. In course of their first five years’ operations, the receipts of

the Company increased nearly fivefold. In January, 1849, a message was

transmitted direct from London to Manchester for the first time.

The Electric Telegraph Company endeavoured to make telegraphic

communication a monopoly by buying up every new invention that seemed

likely to enable any other Company to compete with them. With reference

to the inventions made for improving the telegraph, Mr. Ricardo, the

chairman of the Company, stated some curious facts in 1851. He said,

“It has happened, not once, but I think twenty times, that a man has

brought to us an instrument of great ingenuity for sale; we have taken

him to a cupboard, and brought out some dusty old models, and said,

‘That is your invention, and there is wheel for wheel generally.’

Nevertheless he has, in fact, invented it. The ideas of several men

are set in motion by exactly the same circumstances. One invention was

brought for purchase to the Electric Telegraph Company; no model was

brought with it; there was simply a description of the apparatus. It

was on a principle which was received by electricians as impossible,

and the men of science connected with the Company declared it to be

impossible. Nevertheless the model was brought; and it was found that

the thing was practicable against all rules by which hitherto they

had been guided in the matter. We have bought a good many patented

improvements; in most cases they were valueless in themselves; but in

combination with others which we have, they may be made useful. We have

found, after every possible experiment, that the original system of

the needles is by far the best for all practical purposes. There is not

one invention which is not brought to the Company before it is started

against the Company, and we have expended nearly £200,000 in buying

patents and litigating them; but we find, after all, that the original

patent is by far the best and the most suitable for practical purposes.

There is one patent of Mr. Bain’s for which we gave £8000 or £9000;

although it did not quite come up to our expectations, it has proved

useful in combination with other patents.”

This testimony will appear all the more remarkable when it is added

that between 1837 and 1857 about forty different inventors took out

patents for telegraphic apparatus, and that some of these men took out

several patents. It is remarkable, moreover, that from the time of the

formation of the Company till 1858, Professor Wheatstone did not patent

any improvement of telegraphic apparatus. It has been said that during

these years he entirely ceased to be an inventor, and did not bring

his great electrical knowledge and inventive faculties into use. But

this is not strictly accurate, for circumstances had occurred which

for a time diverted his attention to another field for the application

of electricity in which he became a pioneer. About the year 1850 Sir

Charles Pasley was experimenting as to the explosion of submarine

mines, and being acquainted with Professor Wheatstone and Professor

Daniell, he informed them of his intention to use electricity for that

purpose, and sought their advice on the subject.

These eminent electricians took much interest in the proposal, and

under their superintendence the first arrangements for exploding

submarine charges were worked out in the laboratory of King’s College.

Acting on their advice Sir Charles Pasley used electricity to explode

the charges of gunpowder that blew up the wreck of the _Royal George_

at Spithead, which he was then engaged in removing. In 1853 Sir John

Burgoyne, Inspector General of Fortifications, requested Captain Ward,

R.E., to carry out some experiments for determining the best form of

voltaic battery for military purposes. That officer then made himself

fully acquainted with the labours of Professor Wheatstone and others;

and afterwards reported in favour of a small battery seven inches long

by four wide; but in 1855 Professor Wheatstone, who was then a member

of the Select Committee on Ordnance, advised Sir John Burgoyne to

institute a further experimental inquiry into the relative advantages

of different sources of electricity. This investigation was accordingly

carried out by Professor Wheatstone and Professor Abel; and in the

course of it Wheatstone invented the first efficient magneto-electric

machine for the explosion of mines. It was called the Wheatstone

exploder, and it weighed 32 pounds. In a report on their experiments,

presented to the Secretary for War in 1860, it was stated that by means

of “a magneto-electric apparatus similar to that used in the Chatham

experiments, and termed by Mr. Wheatstone the ‘Magnetic Exploder,’

the ignition at one time of phosphide of copper fuzes, varying in

number from two to twenty-five, is certain, provided these fuzes are

arranged in the branches of a divided circuit; to attain this result

it is only necessary to employ a single wire insulated by a coating of

gutta-percha or india-rubber and simple metallic connections of the

apparatus and the charge with the earth.” They stated that from twelve

to twenty-five charges could be exploded simultaneously on land at a

distance of 600 yards from the apparatus; but the number of submarine

charges which it could explode at one time was more limited. During the

next seven years this apparatus was much used in gunnery experiments as

well as in mining; and several modifications of it were devised on the

Continent and in America. In 1867-8 Professor Wheatstone constructed

a more powerful modification of his magnetic exploder, and Professor

Abel ever afterwards spoke in the highest terms of the ingenuity and

industry with which his former colleague had worked out the solution

of this problem. He said that Professor Wheatstone brought under the

notice of the Government the successful labours of Du Moncel, Savari,

von Ebner, and others on the applications of electricity to military

purposes; and if he had only done that service, he would have done an

important work. But he did more; he constructed the first practical

and thoroughly efficient magneto-electric machine for the explosion of

mines.

Let us now pass from submarine mines to submarine cables. There have

been several claimants to the honour of being the first to develop

the idea of submarine telegraphy; and among them Professor Wheatstone

is entitled to honourable mention. One of the first suggestions of a

sub-aqueous telegraph was made by him. In 1840 he was giving evidence

before a Select Committee of the House of Commons, and after he had

given an account of the short line of telegraph from Paddington to

Drayton, then the only line in existence, he was questioned as to

whether an electric telegraph could be worked over a distance of 100

miles. He replied in the affirmative. “Have you tried to pass the line

through water?” said Sir John Guest. “There would be no difficulty in

doing so,” replied Wheatstone; “but the experiment has not been made.”

“Could you communicate from Dover to Calais in that way?” “I think it

perfectly practicable,” replied the enthusiastic inventor. The subject

thus started for the first time in public was not new to Professor

Wheatstone; for it afterwards appeared from manuscripts in his

possession that he had given much consideration to it in 1837. Mr. John

Watkins Brett, who was also honourably connected with the initiation

of submarine telegraphy, stated in 1857 that he was ignorant until

three or four years previously that a line across the Channel had

been suggested years before by that talented philosopher, Professor

Wheatstone; and he exhibited at the Royal Institution the original

plans of Wheatstone drawn in 1840 for an electric telegraph between

Dover and Calais. The cable he then designed was to be insulated by

tarred yarn and protected by iron wire; and his plan of laying down and

picking up was also shown in the drawing. The man who made the drawing

for Wheatstone went to Australia in 1841, and did not return. But there

were other evidences of its genuineness. Professor Wheatstone showed

his plans to a number of visitors at King’s College, and a Brussels

paper records that in the same year (1840) he repeated his experiments

at the Brussels Observatory in the presence of several literary and

scientific men, for the purpose of showing them the feasibility of

making a cable between Dover and Calais. For carrying out his plans he

designed three new machines, and minutely worked out the other details

of the undertaking. In a manuscript written in 1840 on “a means of

establishing an electric cable between England and France,” he stated

that the wire should form the core of a wrought line well saturated

with boiled tar, and all the lines be made into a rope prepared in the

same manner. His correspondence shows that his plan became the subject

of communications with persons of authority during the next few years;

and in the month of September, 1844, he and Mr. J. D. Llewellyn made

experiments with submerged insulated wires in Swansea Bay. They went

out in a boat from which they laid a wire to Mumblehead Lighthouse,

and they tested various kinds of insulation. These experiments were so

successful that Wheatstone returned to his original Channel project.

His idea, says Mr. R. Sabine, was to inclose the wire, insulated

with worsted and marine glue, in a lead pipe; and for some time he

was engaged in making inquiries as to the nature of the bed of the

Channel and the action of the tides, as well as experiments with the

metals he proposed to use. There is also evidence to show that in 1845

he proposed to use gutta percha in the manufacture of his proposed

cable. It is said that gutta percha was first brought to England in the

previous year, and there was such a demand for the small quantity then

available that he could not get what he wanted of it.

In June 1846, the _Times_ announced, in reference to a statement

made “some time ago that a submarine telegraph was to be laid down

across the English Channel, by which an instantaneous communication

could be made from coast to coast,” that the Lords Commissioners

of the Admiralty, with a view of testing the practicability of

this undertaking had now approved of the projector’s laying down a

submarine telegraph across the harbour of Portsmouth, from the house

of the admiral in the dockyard to the railway terminus at Gosport.

“By this means there will be a direct communication from London to

the official residence of the Port-Admiral at Portsmouth, whereas

at present the telegraph does not extend beyond the terminus at

Gosport, the crossing of the harbour having been hitherto deemed an

insurmountable obstacle.... In a few days after the experiment has

been successfully tested at Portsmouth, the submarine telegraph will

be laid down across the Straits of Dover under the sanction of both

the English and French Governments.” There is evidence extant to show

that Professor Wheatstone was in the previous year in communication

with the Admiralty on the subject of a cable across the Channel. It was

on the twenty-fifth of the same month in which the above remarks were

published that the Corn Law Importation Bill was carried through the

House of Lords; and on the twenty-ninth the Duke of Wellington in the

House of Lords and Sir Robert Peel in the House of Commons announced

the resignation of the Government. Changes of Government, the famine

in Ireland, and the great commercial panic that followed were of more

absorbing interest than the laying of a submarine cable. At all events

the small cable across Portsmouth Harbour was not laid till 1847. It

was then stated that an offer made to the Admiralty to lay down a

telegraph inclosed in metallic pipes was found to be impracticable.

The successful cable had the appearance of an ordinary rope which was

coiled into one of the dockyard boats, and as the boat was pulled

across the telegraph rope was paid out over the stern, an operation

that occupied a quarter of an hour. It worked satisfactorily.

Professor Wheatstone, in an agreement which he made with Mr. Cooke

in April 1843, reserved to himself authority to establish “electric

telegraph communication between the coasts of England and France ...

for his own exclusive profit.” In a subsequent agreement dated October

1845, with reference to the sale of his patents, it was provided that

“Mr. Wheatstone will take the chair of a committee of three, to take

charge of the manufacture of the patent telegraphic instruments,

and the taking out and specifying future patents and matters of the

like nature, at a salary of 700_l._ a year, and shall devote to such

objects what time he shall think necessary. It is also understood that

a patent shall be applied for immediately to secure Mr. Wheatstone’s

improvements in the mode of transmitting electricity across the water;

that Mr. Wheatstone shall superintend the trial of his plans between

Gosport and Portsmouth; and if these experiments prove successful, then

in the practical application of the improvements to the purpose of

establishing a telegraph between England and France, the terms on which

such telegraph is to be held being a matter of arrangement between the

proprietors of the English and French patents.”

But something more than the ingenuity of Professor Wheatstone was

needed to carry the projected cable across the Channel. It required

all the energy and enthusiasm of Mr. J. W. Brett to make it an

accomplished fact. He did for the submarine telegraph what Mr. Cooke

did for Wheatstone’s land telegraph in England, and he always bore

generous testimony to the initiatory efforts of Professor Wheatstone.

Mr. Brett, who was an inventor as well as an _entrepreneur_, in 1845

offered to the Admiralty to connect Dublin Castle by telegraph with

Downing Street for a sum of £20,000, and the offer being refused,

he turned his attention to uniting together France and England by a

submarine line. In 1847 Louis Philippe granted the requisite permission

to land and work a cable on the French coast; but the British public

considered the scheme too hazardous to give it financial support. Three

years later he brought the subject before Louis Napoleon, who was

favourable to it. Accordingly in 1850, when 2000_l._ were subscribed

for the work, a cable was made and laid. On August 28th, 1850, the

paddle steamer _Goliath_, carrying in her centre a gigantic drum, with

thirty miles of telegraph wire in a covering of gutta percha wound

round it, started from Dover about ten o’clock, with a crew of thirty

men and provisions for the day. The track in a direct line to Cape

Grisnez had been previously marked by buoys and flags on staves. As the

steamer moved along that track at the rate of four miles an hour, the

cable was continuously paid out; leaden weights affixed to it at every

one-sixteenth of a mile sank it to the bottom; and about eight o’clock

in the evening the work was done.

Taking up an elevated position at the Dover Railway, Mr. Brett was able

by the aid of a glass to distinguish the lighthouse and cliff at Cape

Grisnez. The declining sun, he says, “enabled me to discern the moving

shadow of the steamer’s smoke on the white cliff, thus indicating

her progress. At length the shadow ceased to move. The vessel had

evidently come to an anchor. We gave them half an hour to convey the

end of the wire to shore, and attach the printing instrument, and

then I sent the first electric message across the Channel: this was

reserved for Louis Napoleon. I was afterwards informed that some French

soldiers, who saw the slip of printed paper running from the little

telegraph instrument, bearing a message from England, inquired how it

could possibly have crossed the Channel, and when it was explained that

it was the electricity which passed along the wire and performed the

printing operation, they were still incredulous. After several other

communications, the words ‘All well’ and ‘Good night’ were printed,

and closed the evening. In attempting to resume communication early

next morning, no response could be obtained.” The cable had broken.

“Knowing the incredulity expressed as to the success of the enterprise,

and that it was important to establish the fact that telegraphic

communication had taken place, I that night sent a trustworthy person

to Cape Grisnez, to procure the attestation of all who had witnessed

the receipt of the messages there; and the document was signed by some

ten persons, including an engineer of the French Government who was

present to watch the proceedings; this was forwarded to the Emperor of

the French, and a year of grace for another trial was granted.”

Near the rugged coast of Cape Grisnez the wire had been cut asunder

about 200 yards out to sea; but though of short duration the experiment

was considered so encouraging that it was determined to lay a much

stronger cable next year, and to land it at a more favourable part

of the French coast. When next year came the public were informed in

the newspapers that the manufacture of the submarine telegraph cable

afforded another instance in which rapidity of execution bordered

on the marvellous, for “though the telegraph-rope was not less than

twenty-four miles in length, it was completed in the short space of

three weeks--an undertaking which manual labour could scarcely effect

in as many years.” This cable was successfully laid, and on Thursday,

the 13th of November, 1851, communications passed between Dover and

Calais. The connections, however, with the land lines, giving direct

communication between London and Paris, were not completed till

the following November. It was remarked at the time as a singular

coincidence that the day chosen for the opening of the Submarine

Telegraph was that on which the Duke of Wellington attended in person

to close the Harbour sessions. It was accordingly resolved by the

promoters that his Grace on leaving Dover by the two o’clock train

for London should be saluted by a gun fired by the transmission of a

current from Calais. It was arranged that as the clock struck two at

Calais the requisite signal was to be passed; and, punctual to the

moment, a loud report reverberated on the water, and shook the ground

with some force. It was then evident that the current had fired a

22-pounder loaded with 10 lbs. of powder, and the report had scarcely

ceased ere it was taken up from the heights by the military who, as

usual, saluted the departure of the Duke with a round of artillery.

Guns were then fired successively on both coasts; Calais firing the

guns at Dover, and Dover returning the compliment to Calais.

Professor Wheatstone also did some useful work in connection with the

first Atlantic cables. In 1855 Professor Faraday was explaining the

subject of induction at the Royal Institution, when it was mentioned

to him that a current was obtained from a gutta percha covered wire,

300 miles long, half an hour after contact with the battery. “I

remember,” says Mr. J. W. Brett in 1857, “speaking to him on the

subject, and inquiring if he did not believe that this difficulty was

to be overcome, and I received from him every encouragement to hope

it might; but it at once became necessary that this point should be

cleared up, or it would be folly to pursue the subject of the union of

America with this country by electricity. I at once earnestly urged on

Mr. Whitehouse to take up this subject, and pursue it independently of

every other experiment, and a successful result was at last arrived

at on 1000 miles and upwards of a continuous line in the submarine

wires in the several cables, when lying in the docks. It did not rest

upon one, but many thousand experiments.” But these experiments did

not solve the problem, which exercised the ingenuity of the greatest

electricians of the age. Professor Wheatstone conducted several series

of experiments to aid in its solution. He showed that iron presented

eight times more resistance to the electric current than copper

did, and that differences in the size and quality of conductors and

insulators affected the transmission of signals.

In 1859 the Board of Trade selected Professor Wheatstone as a member

of the committee appointed to inquire into the subject of submarine

cables with special reference to the Atlantic cable. To that committee

he supplied an elaborate report which would fill fifty pages of this

volume, “On the circumstances which influence the inductive discharge

of submarine telegraph cables.” He was also a member of the scientific

committee appointed in 1864 to advise the Atlantic Telegraph Company as

to the manufacture, laying, and working of the cables of 1865 and 1866.

In 1848 Lord Palmerston made a remark about the telegraph that was

at the time regarded as a jest. He said the day would come when a

minister, if asked in Parliament whether war had broken out in India,

would reply, “Wait a minute, I’ll just telegraph to the Governor

General, and let you know.” At that time two or three months usually

elapsed between the sending of a message and the receipt of an answer

from Calcutta to London; and hence the remark of Lord Palmerston was

derided as a joke. But in 1855 the electric telegraph performed a feat

which astonished the nations of Europe. On the 2nd of March the Czar

Nicholas died at St. Petersburg at one o’clock; and the same afternoon

the Earl of Clarendon announced his death in the House of Lords--the

intelligence having been received by two different lines of telegraph.

Two years afterwards two different schemes were promoted for connecting

Europe with India by telegraph; but this was not successfully

accomplished till eight years afterwards. Three years before the

Palmerstonian jest of 1848 became an accomplished fact, Professor

Wheatstone communicated to Lord Palmerston the effects of a new

telegraphic invention which seemed nearly as incredible as the idea of

telegraphing to India appeared a few years previously. The noble lord

was at Oxford University receiving his honorary degree, and was watched

by Sir Henry Taylor at an evening party as the Professor gave him a

somewhat prolonged explanation of his new invention for facilitating

telegraphy. “The man of science,” says Sir Henry, “was slow, the man

of the world _seemed_ attentive; the man of science was copious, the

man of the world let nothing escape him; the man of science unfolded

the anticipated results--another and another, the man of the world

listened with all his ears: and I was saying to myself, ‘His patience

is exemplary, but will it last for ever?’ when I heard the issue:--‘God

bless my soul, you don’t say so! I _must_ get you to tell that to the

Lord Chancellor.’ And the man of the world took the man of science to

another part of the room, hooked him on to Lord Westbury, and bounded

away like a horse let loose in a pasture.”

If it be true that men of the world regarded with impatience the

ingenious devices of Professor Wheatstone, very different was the

reception accorded to them by the prince of modern scientists. In the

beginning of the following year (19th January, 1858) Professor Faraday

wrote the following letter to him: “While thinking of your beautiful

telegraphs it occured to me that perhaps you would not think ill of

my proposing to give an account of the magneto-electric telegraph

and the recording telegraph on a Friday evening after Easter--about

the end of May or June. I suppose all will be safe by that time. I

think that by the electric lamp and a proper lens, we might throw

the image of the face on to the wall, and so we may illustrate the

action to the whole audience.” The proposed lecture was delivered by

Professor Faraday in the Royal Institution on June 11th, 1858, and his

subject was “Wheatstone’s electric telegraph in relation to science

(being an argument in favour of the full recognition of science as a

branch of education).” That lecture was very interesting, not only as

indicating the progress made in the telegraph, but as showing his high

appreciation of the inventive ingenuity which had accelerated that

progress. So far from representing the telegraph as “no invention” he

spoke of it as a series of inventions. “It teaches us to be neglectful

of nothing,” he said; “not to despise the small beginnings, for they

precede of necessity all great things in the knowledge of science,

either pure or applied. It teaches a continual comparison of the _small

and great_, and that under differences almost approaching the infinite:

for the small as often comprehends the great in principle as the great

does the small.” As to the work done by Professor Wheatstone, he said:

“Without referring to what he had done previously, it may be observed

that in 1840 he took out patents for electric telegraphs, which

included, amongst other things, the use of the electricity from magnets

at the communicators--the dial face--the step-by-step motion--and the

electro-magnet at the indicator. At the present time, 1858, he has

taken out patents for instruments containing all these points; but

these instruments are so altered and varied in character above and

beyond the former, that an untaught person could not recognise them.

In the first instruments powerful magnets were used, and keepers[7]

with heavy coils associated with them. When magnetic electricity was

first discovered, the signs were feeble, and the mind of the student

was led to increase the results by increasing the force and size of

the instruments. When the object was to obtain a current sufficient to

give signals through long circuits, large apparatus were employed, but

these involved the inconveniences of inertia and momentum; the keeper

was not set in motion at once, nor instantly stopped; and if connected

directly with the reading indexes, these circumstances caused an

occasional uncertainty of action. Prepared by its previous education,

the mind could perceive the disadvantages of these influences, and

could proceed to their removal.... The alternations or successions of

currents produced by the movement of the keeper at the communicator,

pass along the wire to the indicator at a distance; there each one

for itself confers a magnetic condition on a piece of soft iron, and

renders it attractive or repulsive of small permanent magnets; and

these, acting in turn on a propelment, cause the index to pass at will

from one letter to another on the dial face. The first electro-magnets,

_i.e._, those made by the circulation of an electric current round a

piece of soft iron, were weak; they were quickly strengthened, and

it was only when they were strong that their laws and actions could

be successfully investigated. But now they are required small, yet

potential; and it was only by patient study that Wheatstone was able

so to refine the little electro-magnets at the indicator as that they

shall be small enough to consist with the fine work there employed,

able to do their appointed work when excited in contrary directions

by the brief currents flowing from the original common magnet, and

unobjectionable in respect of any resistance they might offer to these

tell-tale currents. These small transitory electro-magnets attract and

repel certain permanent magnetic needles, and the to-and-fro motion of

the latter is communicated by a propelment to the index, being there

converted into a step-by-step motion. Here everything is of the finest

workmanship; the propelment itself requires to be watched by a lens, if

its action is to be observed; the parts never leave hold of each other;

the holes of the axes are jewelled; the moving parts are most carefully

balanced, a consequence of which is that agitation of the whole does

not disturb the parts, and the telegraph works just as well when it is

twisted about in the hands, or placed on board a ship or in a railway

carriage, as when fixed immovably. All this delicacy of arrangement

and workmanship is introduced advisedly; for the inventor considers

that refined and perfect workmanship is more exact in its action, more

unchangeable by time and use, and more enduring in its existence, than

that which, being heavier, must be coarser in its workmanship, less

regular in its action, and less fitted for the application of force by

fine electric currents.... Now,” added Faraday, “there was no chance in

these developments;--if there were experiments, they were directed by

the previously acquired knowledge;--every part of the investigation was

made and guided by the instructed mind.... The beauty of electricity,

or of any other force, is not that the power is mysterious and

unexpected, but that it is under _law_, and that the taught intellect

can even now govern it largely.”

The instrument which Faraday described in such appreciative terms has

superseded the step-by-step instrument which was invented in 1840. The

new instrument, like the old one, has a dial with the letters of the

alphabet round the edge, and when in operation the indicating hand

or finger points successively to each letter forming the message,

which can thus be read by anyone. The sending instrument also has a

dial round which are the letters of the alphabet, and projecting from

each letter is a brass key or stud. The new mechanism inside this

instrument is so ingeniously designed that when the sender of a message

turns round a small handle which puts in motion the magneto-electric

apparatus so as to generate electric currents, the indicating finger

on the receiving dial moves round till it is stopped at the desired

letter. This stoppage is effected by the sender depressing the brass

stud which represents the desired letter. By this depression of

any particular stud, the currents of electricity are cut off just

when the indicating finger reaches the letter on the receiving dial

corresponding to that of the depressed stud at the sending instrument;

and the indicating finger remains at that letter till the stud of

another letter is depressed, whereupon the indicating finger moves

along the receiving dial till it reaches again the letter corresponding

to that of the depressed stud. No knowledge of electrical science or of

mechanics is needed to work this instrument, the hidden mechanism of

which cannot be easily described in popular language. Surely it is an

illustration of the classic adage that the highest art is to conceal

art.

The working of this instrument excelled all others in simplicity; and

at the same time Professor Wheatstone invented one which exceeded all

others in rapidity. The former became known as Wheatstone’s A, B, C

instrument, the latter as Wheatstone’s automatic fast speed printing

instrument. The latter is so constructed that the passage of the

current is regulated by means of a perforated strip of paper. The

apparatus consists of three parts--the perforator, the transmitter,

and the receiver. The perforator has keys which when pressed down by

an operator punch in a strip of paper combinations of holes, which

represent letters of the alphabet, thus

A B C

o o o o o o o o o o

o o o o o o o o o o

One person working a perforator can simultaneously punch duplicate

messages, but only one strip of perforated paper can be put into the

transmitter, which draws it forward with a continuous motion. Two

small pins, one on each side, are underneath the strip of paper, and

whenever one of these pins comes to a perforated hole it momentarily

rises through it, and imparts sufficient electricity from the battery

to the telegraph wire to move a pen at the other end of the wire, so

as to make a mark in ink on a clean strip of paper passing through

the receiving instrument. The ink marks thus produced in combinations

represent letters of the alphabet, namely,

A B C

__ ______ ____ __ __ __ ______ __ ______ __

The receiver is thus a recording instrument so exact and sensitive that

it mechanically and rapidly imprints on a strip of paper dots, dashes,

and spaces, which, in a sense, correspond with the holes perforated

in the tape passing through the transmitter, at the other end of the

wire. When this apparatus was invented it was represented as capable of

forwarding messages at the rate of 500 letters per minute, being five

times faster than any other system then in use.

In 1868 the inventor stated that although for rapidity of transmission

his automatic instrument had never been surpassed, he did not expect

that the existing instruments would in all cases be given up for it.

He believed it would be very useful on all “lines of great traffic,”

and particularly on those lines over which newspaper intelligence is

sent. In 1870 the telegraph lines of the United Kingdom were acquired

by the Government--a step which Professor Wheatstone advocated as

the best means of cheapening messages and extending the telegraph to

places unapproached by the Telegraph Companies. Let us see how his

expectations have been realised.

In 1872 Mr. Culley, the engineer-in-chief of the Telegraphic system

of the United Kingdom, stated that in order to increase the number

of messages which could be sent through the wires in a given time, a

very large use had to be made of the Wheatstone automatic instrument,

which was in use by the Electric Company before the transfer to

the Government. There were only four circuits then; but in the two

years following the transfer fifteen circuits were supplied with

that apparatus. In addition to these automatic circuits for ordinary

business, the Telegraph Department had also fitted up with that

system what they called the Western News circuit running from London

to Bristol, Gloucester, Cardiff, Newport, Exeter, and Plymouth, the

news being then sent to all these places simultaneously, and at the

rate of fifty to fifty-five words a minute. A very great improvement

had also been effected, at considerable expense, in the single-needle

instrument. A very large number of inventions had been brought before

the Department, and it might have been hoped that very considerable

advantage to the public would have arisen from the breaking up of the

monopoly of the Companies and the private interests which almost all

the officers had in perpetuating the form of some old instrument. But

Mr. Culley had to report that not in any one instance had any apparatus

or system of signalling of practical value been laid before him. One

system only had been of such a nature as could possibly have any value,

and he said that one would have required fully ten years to mature

before it could be brought out.

Professor Wheatstone lived to see 140 of his automatic instruments in

use. In 1872 he applied to the Judicial Committee of the Privy Council

for a prolongation of his patent; and it being then stated that he had

received £12,000 in 1870, when the transfer of the telegraphs took

place, the Government agreed to pay him an additional sum of £9,200 in

six yearly instalments as compensation for his patent rights.

In 1879 Mr. Preece, the electrician to the Post Office, said that the

automatic transmitter “is an instrument of great delicacy and great

power; it is now used to an enormous extent in this country, and it is

one that we are improving every day. For instance, while about this

time last year we were able to transmit all our news to Ireland at

the rate of 60 words a minute, we are now doing it with ease at the

rate of 150 words a minute; and with the improvements which we have

now in hand, we shall be able next year to transmit nearly 200 words a

minute.” This expectation was realised. Although experience suggested

improvements in nearly every part of the apparatus, the leading

principles remained the same. In 1885 Mr. Preece gave the following

account of the successive stages of the progress made: it was capable

of transmitting in 1877, 80 words per minute; in 1878, 100; in 1879,

130; in 1880, 170; in 1881, 190; in 1882, 200; in 1883, 250; in 1884,

350; in 1885, 420. It thus appears that if three men were speaking

at the same time, one of Wheatstone’s automatic instruments could

transmit the three speeches in the same time that they were spoken, the

instrument transmitting three times as fast as one man could speak.

Towards the close of the first half century of the existence of the

telegraph, the Wheatstone automatic transmitter achieved the great

feat of transmitting 1,500,000 words from London on the night when Mr.

Gladstone explained his plan for giving self-government to Ireland, On

that occasion (April 8, 1886) one hundred Wheatstone’s perforators

were used in the Central Telegraph Office in London to prepare the

messages. Thirty of these perforators punched six slips at once,

thirteen punched three slips at once, thirty-one punched two slips at

once, and twenty-six punched single slips. The largest number of words

previously transmitted in one night was 860,000; and to give some idea

of what 1,500,000 words represent, it may be added that if an average

quick speaker like Mr. Gladstone were to speak without any stoppage for

a week, night and day, that would just be about the number of words

that he would utter, or that another person could read aloud.

FOOTNOTES:

[7] The keeper or armature is the piece of iron which is

placed across the ends or poles of a horseshoe magnet.

CHAPTER IV.

“A name, even in the most commercial nation, is one of the

few things which cannot be bought. It is the free gift

of mankind, which must be deserved before it will be

granted, and is at last unwillingly bestowed. But this

unwillingness only increases desire in him who believes

his merit sufficient to overcome it.”--DR. JOHNSON.

From the two preceding chapters it appears that Professor Wheatstone

was not only the inventor of the first electric telegraph used in

England, but that he at last invented the most perfect transmitter of

telegraphic intelligence. He not only nursed it from its birth, but

reared it to maturity; and the period that elapsed between his first

and last invention of telegraphic apparatus was exactly twenty-one

years. But this was not enough for his versatile mind to accomplish.

He had worked successfully as an inventor for seventeen years before

his first telegraph was invented, and he continued to work at his

favourite subjects for seventeen years after his last great telegraphic

invention. Having confined our attention in the last two chapters

almost exclusively to the progress of the telegraph, it remains for

us to follow the inventor into the bye-paths which he now and then

delighted to tread, as well as to follow his course during his latter

years along the highway of electrical science in which his genius

appeared to find its most congenial exercise.

It has already been explained that in the early years of his electrical

researches, he was one of the first men in England to draw attention

to the thermo-electric pile originally constructed by Nobili and

Melloni in 1831; it consisted of a bundle or pile of small plates of

bismuth and antimony, which when heated converts heat into electricity.

By connecting this pile by coils of wire with a galvanometer (a

movable needle) it becomes a delicate means of indicating minute

changes of temperature, the electricity generated by heat moving the

needle. This instrument can be affected by the warmth of the hand

held several yards away from it; and it is believed that without it,

as a thermoscope, the important discoveries respecting radiant heat

made by Professor Tyndall and others would have been impossible. It

has even been found possible by means of this sensitive apparatus

to estimate the amount of radiant heat emitted by insects. In 1837

Professor Wheatstone predicted great results from the thermo-electric

pile as a source of electricity, and in 1865 he constructed a powerful

thermo-electric battery of that description. It was composed of

sixty pairs of small bars, and it was stated that by its action “a

brilliant spark was obtained, and about half an inch of fine platinum

wire when interposed was raised to incandescence and fused; water was

decomposed, and a penny electro-plated with silver in a few seconds;

whilst an electro-magnet was made to lift upwards of a hundredweight

and a half.” This thermo-electric battery may be said to have

electrified the imaginations of men of science, who saw visions and

dreamt dreams about its future. For instance, it was suggested that

“like windmills, thermo-electric batteries might be erected all over

the country for the purpose of converting into mechanical force, and

thus into money, gleams of sunshine which would be to them as wind to

the sails of a mill.” Many other attempts have been made to construct

a thermo-electric pile capable of being used as a generator of

electricity instead of the voltaic battery or the dynamo; and although

much progress was made in later years, the difficulty in the way, as

Lord Rayleigh observed in 1885, was the too free passage of heat by

ordinary conduction from the hot to the cold junction.

However, Professor Wheatstone, having once taken in hand the production

of electricity by an improved method, worked at the problem until he

solved it. The electrical invention that ranks next in importance to

the telegraph is the dynamo machine, and this also he had a share

in introducing and improving. Its first conception has been claimed

by different electricians. On the 4th of February, 1867, two papers

were read before the Royal Society, one by Sir William Siemens, “On

the conversion of dynamic into electrical force without the use of

permanent magnetism,” and the other by Professor Wheatstone, “On the

augmentation of the power of a magnet by the reaction thereon of

currents induced by the magnet itself.” Both papers described the same

discovery--the dynamo machine. The instrument described by Professor

Wheatstone was made of a strip of soft iron, the core, fifteen inches

long, bent in the form of a horse-shoe, and wound round in the

direction of its breadth by 640 feet of insulated copper wire (covered

with silk). The keeper or armature (the piece of iron extending across

the ends of the horse shoe magnet) was hollow at two sides for the

reception of eighty feet of insulated wire coiled lengthwise. The two

wires being connected so as to form a single circuit, and the armature

made to rotate in the opposite direction to that of the hands of a

watch, powerful electrical effects were produced. The electricity

generated by this motion of the armature soon made four inches of

platinum wire red-hot, and decomposed water. These effects were thus

explained by Professor Wheatstone: The electro-magnet always retains

a slight residual magnetism, so is always in the condition of a weak

permanent magnet; the motion of the armature occasions feeble currents

in its coils in alternate directions, which, brought into the same

direction, pass into the coil of the horse-shoe electro-magnet in such

a manner as to increase the magnetism of the iron core; the strength

of the magnet being thus increased, it produces in its turn stronger

currents in the coil of the armature; and this alternate increase goes

on until it reaches a maximum dependent on the rapidity of the motion

and the capacity of the magnet.

Sir William Siemens, whose paper was sent in ten days before

Professor Wheatstone’s, described a similar machine, but that they

were independent discoveries has never been questioned. It was

almost inevitable, however, that the question of priority should be

discussed. Mr. Robert Sabine, who defended the rights of Professor

Wheatstone, stated in 1877 that the time when “the idea of making a

machine which would work into itself occurred to Professor Wheatstone,

it is of course after his death impossible to determine, unless some

manuscript notes should turn out in evidence. I am also unable to

ascertain when the first experimental apparatus was made and tried. We

must therefore start from the later stage, viz., the finished machine

which was exhibited at the Royal Society in February, 1867.” It is

interesting, however, to go a few years further back, and to find

that the idea of producing powerful electrical effects by mechanical

means was present in the mind of Professor Wheatstone a quarter of a

century before it was announced as an accomplished fact. Early in 1843

he showed Professor A. De La Rive his new electro-magnetic telegraph;

and in publishing an account of it the French Professor said that

he (Wheatstone) “has endeavoured to apply the same principle to the

production of a useful mechanical force; but he does not seem to me to

have completely succeeded on this point; and I am convinced that a long

period must yet elapse before steam is in this respect dethroned by

electricity.”

Now it is a remarkable fact that at that very time there was a plan

of a dynamo in MS., which unfortunately did not attract attention

till thirty years afterwards. Dr. Gloesener, professor of physics at

Liège University, in an extant MS. which was dated 20th of April,

1842, and which remained in the custody of public bodies in Belgium

from that date, described electro-magneto oscillating and rotatory

motors which he designed, and which he spoke of “as destined to take

the place of steam and other motors.” In honour of this inventor, who

died unrewarded for his prescience, the Electrical Congress at Paris

admitted his daughter as their only lady member. However, Professor

Wheatstone did not announce the practical realisation of his idea

till February, 1867. “The machines then exhibited,” continues Mr. R.

Sabine, “were made for Professor Wheatstone by Mr. Stroh in the months

of July and August, 1866. When they were finished, tried, and approved

of, they were in the usual course of business charged for by Mr. Stroh

on the 12th of September, 1866. Mr. S. A. Varley says his machine (as

it was exhibited at the Loan Collection) was completed and tried at

the end of September or the beginning of October, 1866. Sir William

Siemens says that his brother tried his first experimental machine

in December, 1866. It is clear therefore that Professor Wheatstone’s

machines--those exhibited at the Royal Society--were completed, tried,

and charged for, before the first experimental machines of Sir W.

Siemens or Mr. Varley were finished or ready for trial. The date when

the undefined idea of making any machine first occurred to an inventor

is of very little comparative importance, unless the idea be productive

of some evidence of its existence, without which one would, I think,

be inclined to suspect that memory might after a lapse of years be a

little treacherous. Who had the first happy inspiration of a reaction

machine we can scarcely expect to know now. Of its fruits we have

better evidence, and I venture to think that the claims of the three

inventors in question stand thus:

“Professor Wheatstone was the first to complete and try the reaction

machine.

“Mr. S. A. Varley was the first to put the machine officially on record

in a provisional specification, dated 24th of December, 1866, which was

therefore not published till July, 1867.

“Dr. Werner Siemens was the first to call public attention to the

machine in a paper read before the Berlin Academy on the 17th of

January, 1867.”

In such cases the date of publication is generally regarded as the date

of discovery; but whoever was the first inventor of the dynamo, it is

now admitted that Professor Wheatstone’s machine was the most complete.

After explaining how the rotation of the armature generated currents of

electricity in the magnet, he stated that “a very remarkable increase

of all the effects, accompanied by a diminution in the resistance of

the machine, is observed when a cross wire is placed so as to divert a

great portion of the current from the electro-magnet. Four inches of

platinum wire, instead of flashing into redness and then disappearing,

remain permanently ignited; the inductorium wire, which before gave

no spark, now gave one of a quarter of an inch in length; and other

effects were similarly increased.” Strange to say this discovery,

announced in 1867, lay dormant till 1880, and then it was utilised by

Sir William Siemens so as to obviate the great fluctuations previously

experienced in electric-arc lighting. Till then the electric light

often flickered instead of shining steadily, and the cause of its

irregularity puzzled the electricians. In 1880 Sir William Siemens gave

Professor Wheatstone full credit for having suggested a remedy for this

defect in 1867.

Such an array of electrical inventions and discoveries was surely

enough for one man; but electricity was only one of the many subjects

that engaged his attention or exercised his ingenuity. Having traced

the progress of his electrical inventions over a period of forty

years, we must now collect some of the fruits of his labour in other

sciences during that period. After his initial success with the

electric telegraph in 1837, he began to publish in the following year

his _Contributions to the Physiology of Vision_, in which he gave the

results of experiments showing “that there is a seeming difference in

the appearance of objects when seen with two eyes, and when only one

eye is employed; and that the most vivid belief in the solidity of an

object of three dimensions arises from two perspective projections of

it being simultaneously presented to the mind.” At the same time he

gave a description of his newly-invented instrument for illustrating

these phenomena--the stereoscope, which was first announced in 1838,

and was improved in course of the next fourteen years.

When he described the stereoscope to the British Association in 1838

and explained the scientific principle which it illustrated, Sir David

Brewster said he was afraid that the members could scarcely judge--from

the very brief and modest account given by Professor Wheatstone of

the principle and of the instrument devised for illustrating it--of

its extreme beauty and generality. He (Sir David) considered it one

of the most valuable optical papers which had been presented to the

Association. He observed that when taken in conjunction with the law of

visible direction in binocular vision, it explained all those phenomena

of vision by which philosophers had been so long perplexed; and that

vision in three dimensions received the most complete explanation

from Professor Wheatstone’s researches. At the same time Sir John

Herschel characterised Professor Wheatstone’s discovery as one of the

most curious and beautiful for its simplicity in the entire range of

experimental optics.

At the date of the publication of his experiments on binocular vision,

said Professor Wheatstone, the brilliant photographic discoveries of

Talbot, Niepce, and Daguerre had not been announced to the world, as

illustrating the phenomena of the stereoscope. He could therefore at

that time only employ drawings made by the hands of the artists. “Mere

outline figures, or even shade perspective drawings of simple objects,

did not present much difficulty; but it is evidently impossible,” he

says, “for the most accurate and accomplished artist to delineate by

the sole aid of his eye the two projections necessary to form the

stereoscopic relief of objects as they exist in nature with their

delicate differences of outline, light, and shade. What the hand of

the artist was unable to accomplish, the chemical action of light,

directed by the camera, is enabled to effect. It was at the beginning

of 1839, about six months after the appearance of my memoir in the

_Philosophical Transactions_, that the photographic art became known,

and soon after, at my request, Mr. Talbot, the inventor, and Mr. Collen

(one of the first cultivators of the art) obligingly prepared for me

stereoscopic Talbotypes of full-sized statues, buildings, and even

portraits of living persons. M. Quetelet, to whom I communicated this

application and sent specimens, made mention of it in the _Bulletins_

of the Brussels Academy of October 1841. To M. Fizeau and M. Claudet I

was indebted for the first daguerreotypes executed for the stereoscope.”

As indicating the relations that continued to exist between him and Sir

David Brewster on the subject of vision, it is worthy of remark that

in 1844 Professor Wheatstone brought before the British Association

some singular effects produced by certain colours in juxtaposition.

Observing that a carpet of small pattern in green and red appeared in

the gas-light as if all the parts of the pattern were in motion, he

had several patterns worked in various contrasted colours in order to

verify and study the phenomena. Both he and Sir David Brewster brought

to York separate communications on this subject, and specimens of

coloured rugwork to illustrate it; but on seeing Professor Wheatstone’s

specimens, Sir David withheld both his paper and his illustrations, and

simply made a few remarks on Wheatstone’s paper, stating that when he

came to York he did not know that the phenomena were produced by any

other colours but red and green, and that he was indebted to Professor

Wheatstone for showing him that red and blue had the same effect.

The Professor accounted for it by saying that the eye retained its

sensibility for various colours during various lengths of time.

In the stereoscope designed by Professor Wheatstone mirrors were used

instead of lenses; and though the effect produced by mirrors was

similar to that which we now see by means of lenses, its startling

novelty did not excite popular interest. Indeed it was only used by

two or three Professors to illustrate optical phenomena; and with that

exception it might be said to have been unhonoured and unused for

several years. It was Sir David Brewster who proposed to use lenses

instead of mirrors, and thus gave to it the form in which it eventually

became popular; but even then its popularity might be described as of

foreign origin. In addressing the British Association in 1848 on the

theory of vision, Sir David Brewster said that the solution of some

problems that had long baffled opticians was greatly facilitated by

that beautiful instrument, the stereoscope of Professor Wheatstone.

Next year Sir David exhibited his new form of the stereoscope before

the British Association at Birmingham, and in 1850 he exhibited it at

Paris, and explained it to M. Duboscq Soleil, an optician of that city,

who was so impressed with its advantages that he began to manufacture

it, and to call public attention to its powers. One was also exhibited

before the French Academy of Sciences, who appointed a committee to

examine it.

In 1849 Sir David Brewster offered his improvement in the stereoscope

gratuitously to opticians in Birmingham and London; but they did

not accept it; and it was only after it became an object of wonder

in France that it began to be appreciated in England. At the Great

Exhibition of 1851 M. Duboscq Soleil showed a beautiful instrument

together with a fine set of binocular daguerreotypes; and another

instrument by the same maker was presented by Sir David Brewster to the

Queen. In the same year some were exhibited at one of the _soirées_ of

Lord Rosse, where they excited much interest. The attention of English

photographers being then directed to it, photographic pictures and

portraits began to be executed for it in abundance. The stereoscope

soon came to be in demand; it was manufactured by English as well as

French makers; and thus became a favourite ornament or scientific

curiosity. During the next five years 500,000 stereoscopes were sold.

While Sir David Brewster did so much to make the stereoscope popular,

Professor Wheatstone was generally accredited with the original

invention. In 1849 the eminent French philosophers, MM. L. Foucault

and J. Regnault, stated in the _Comptes Rendus_ that “in a beautiful

investigation on the vision of objects of three dimensions, Professor

Wheatstone states that when two visual fields, or the corresponding

elements of the two retinæ, simultaneously receive impressions from

rays of different refrangibility, no perception of mixed colours is

produced. The assertion of this able philosopher being opposed to

the opinion of the majority of those who have attended to the same

subject, we have thought it useful to repeat, modify, and extend these

experiments; and the stereoscope of Professor Wheatstone offered a

simple means of disentangling these delicate observations of all

complication capable of injuriously affecting the accuracy of the

physiological results.”

In an account of it published in London in 1851 it was truly stated

that the phenomena of vision had engaged the attention of the most

acute philosophers; and that the researches of Professor Wheatstone

had done more than those of any other man to explain the result of

single vision with a pair of eyes while under the influence of two

impressions; for in his stereoscope two images drawn perspectively upon

plane surfaces, when viewed at the angle of reflection appear to be

converted into a solid body, and to convey to the mind an impression of

length, breadth, and thickness. At the same time it was explained that

Sir David Brewster modified the instrument and imitated the mechanical

conditions of the eye by cutting a lens into halves, and placing each

half so as to represent an eye with a distance of two and a half

inches between them. Although it was this use of lenses that made the

stereoscope fashionable, Professor Wheatstone continued to recommend

his original reflecting instrument as the most efficient form, not

only for investigating the phenomena of binocular vision, but also for

exhibiting the greatest variety of stereoscopic effects, “as it admits

of every required adjustment, and pictures of any size may be placed in

it.”

But in 1856 the chorus of unanimity as to the original invention of

the stereoscope was broken. Detraction then began. A book, which was

published in that year, not only disputed the scientific accuracy

of the principles of vision enunciated by Professor Wheatstone,

but endeavoured to divest him of all credit in connection with the

invention of the stereoscope. Who ever could have written such a book?

Sir David Brewster! Nor did a book suffice. In 1860 he read a paper

before the Photographic Society of Scotland “respecting the invention

of the stereoscope in the sixteenth century and of binocular drawings

by Jacopo da Empoli, a Florentine artist.” He stated that inquiry into

the history of the stereoscope showed that its fundamental principle

was known even to Euclid; that it was distinctly described by Galen

1500 years ago; and that Baptista Porta had, in 1599, given such a

complete drawing of the two separate pictures as seen by each eye,

and of the combined picture placed between them, that in it might

be recognised not only the principle, but the construction of the

stereoscope.

It is noteworthy that Sir David Brewster first gave Professor

Wheatstone the credit of being the inventor of the telegraph, and

afterwards ridiculed his claims.

As to the principle of the stereoscope, it was at the meeting of the

British Association in 1848 that Sir David Brewster definitely disputed

the theory of vision which ascribes to experience instead of intuition

the correct perception of objects and of distances with two eyes as

well as with one. He observed that an infant obtained his first glances

of the external world by opening on it both eyes which evidently

conveyed single vision to the mind; and in like manner he contended

that young animals saw distances correctly almost at the instant of

their birth. The duckling ran to the water almost as soon as it broke

the shell; the young boa constrictor would involve and bite an object

presented to it; and on the other hand no person ever saw a child use

such motions as proved it to perceive objects at its eye, to grasp at

the sun or moon or other inaccessible objects, but quite the contrary.

Dr. Whewell entirely dissented from the views of Sir David Brewster,

which were not new; and in confirmation of Dr. Whewell’s contention

that experience was a necessary guide in the use of the senses, a

Bristol oculist gave several instances of persons who on being restored

to sight from total blindness could not at first form any idea of the

distances, or directions, or shapes of bodies; in one instance the

patient, for a length of time, was in the habit of shutting her eyes

entirely and feeling the objects, in order to get rid of the confusion

which vision gave rise to; and it was only as her experience grew more

perfect that she saw with increasing correctness and pleasure, until

at length her sight became perfect. The controversy on this subject

has engaged the attention of many philosophers and has not yet been

settled. In later years Helmholtz, who preferred the mirror stereoscope

of Wheatstone to the lenticular one of Brewster on the ground that the

former gave more sharply-defined effects, stated that the hypotheses

successively formed by the various supporters of the intuitive theories

of vision were quite unnecessary, as no fact had been discovered

inconsistent with the empirical theory, which supposes nothing more

than the well-known association between the impressions we receive and

the conclusions we draw from them, according to the fundamental laws of

daily experience.

In 1851 Professor Wheatstone invented the pseudoscope, an instrument

which conveys to the mind false perceptions of all external objects,

called conversions of relief, because the illusive appearance had the

same relation to that of the real object as a cast to a mould or a

mould to a cast. Thus a china vase ornamented with flowers in relief

showed in the pseudoscope a vertical section of the interior with

painted hollow impressions of the flowers. In like manner a bust became

a deep hollow mask. When two objects at different distances were viewed

through it, the most remote object appeared the nearest, while the

nearest became the most remote. A flowering shrub in front of a hedge

appeared in the pseudoscope as behind the hedge, and a tree standing

outside a window was transferred to the inside of the room.

This instrument has been useful in illustrating mental phenomena

according to the impressions it produces on observers. It is found

that with most persons the inverted appearance that an object presents

when seen through the instrument is alone seen at first; but after the

real form of the object becomes known, their visual perception is so

much under the control of their matter-of-fact experience that they are

unable again to see the inversion of the object. With other observers

the real appearance of the object lasts a shorter or longer time, after

which their visual impressions predominate to such an extent that it

again appears inverted.

Nor did his fertility in illustrating visual effects end here. Mr. J.

Plateau stated in the journal of the Belgian Royal Academy for 1851

that Professor Wheatstone had communicated to him a plan for combining

the principle of the stereoscope with that of the Phenakisticope,

whereby figures simply painted upon paper would be seen both in relief

and in motion, thus presenting all the appearances of life.

In 1851 he supplied the scientific world with a mechanical illustration

of the earth’s rotatory motion which was much admired, and which set at

rest some disputed points. Questions had been raised at that time as

to the effect which the rotation of the earth had upon bodies which,

like the pendulum, oscillated from fixed points; and M. Foucault

designed mechanical means of showing such effects which were said

to make the rotation of the earth as evident to the sight as that

of a spinning-top. His original experiment was shown in Paris to M.

Arago and other scientific men, and was described as follows:--To

the centre of the dome of the Pantheon (272 feet high) a fine wire

was attached, from which a sphere of metal, four or five inches in

diameter, was suspended so as to hang near the floor of the building.

This apparatus was put in vibration after the manner of a pendulum.

Under, and concentrical with it, was placed a circular table, some

twenty feet in diameter, the circumference of which was divided into

degrees, minutes, &c., and the divisions were numbered. The elementary

principles of mechanics showed that, supposing the earth to have the

diurnal motion upon its axis which explains the phenomena of day and

night, the plane in which the pendulum vibrated would not be affected

by this diurnal motion, but would maintain strictly the same direction

during twenty-four hours. In this interval, however, the table over

which the pendulum was suspended would continually change its position

in virtue of the diurnal motion, so as to make a complete revolution in

about 30h. 40m. Since, then, the table thus revolved, and the pendulum

which vibrated over it did not revolve, a line traced upon the table

by a point or pencil projecting from the bottom of the ball would

change its direction relatively to the table from minute to minute, and

from hour to hour; so that when paper was spread upon the table, the

pencil formed a system of lines radiating from the centre of the table;

and the two lines thus drawn after the interval of one hour always

formed an angle with each other of about eleven and a half degrees,

being the twenty-fourth part of the circumference. This was actually

shown to crowds who daily flocked to the Pantheon to witness this

remarkable experiment. The practised eye of a correct observer, aided

by a magnifying glass, could actually see the motion which the table

had in common with the earth under the pendulum between two successive

vibrations, it being apparent that the ball did not return precisely to

the same point of the circumference of the table after two successive

vibrations.