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Finally, after some weeks delay, it was decided to introduce what has become the most familiar feature of the landscape of civilization, and string the wires on poles. There is little need to follow the enterprise further. Morse stayed with one instrument in the Capitol at Was.h.i.+ngton, and Vail carried another with him at the end of the line. Already the type-and-rule and all the symbols and dictionaries had been discarded, and the dot-and-dash alphabet was subst.i.tuted. On April 23d, 1844, Vail subst.i.tuted the earth for the metallic circuit as an experiment, and that great step both in knowledge and in practice was taken.
Within an incredibly brief s.p.a.ce the Morse Electric Telegraph had spread all over the world. No man's triumph was ever more complete. He pa.s.sed to those riches and honors that must have been to him almost as a fulfilled dream. In Europe his progresses were like those of a monarch.
He was made a member of almost all of the learned societies of the world, and on his breast glittered the medals and orders that are the insignia of human greatness. A congress of representatives of ten of the governments of Europe met in Paris in 1858, and it was unanimously decided that the sum of four hundred thousand francs--about a hundred thousand dollars--should be presented to him. He died in New York in 1872.
[Ill.u.s.tration: PROF. HENRY'S ELECTROMAGNET AND ARMATURE]
Yet not a single feature of the invention of Morse, as formulated in his caveat and described in his original patent, is to be found among the essentials of modern telegraphy. They had mostly been abandoned before the first line had been completed, and the arrangements of his a.s.sociate, Vail, were subst.i.tuted. Professor Joseph Henry had, in 1832, constructed an electromagnetic telegraph whose signals were made by sound, as all signals now are in the so-called Morse system. He hung a bar-magnet on a pivot in its center as a compa.s.s-needle is hung. He wound a U-shaped piece of soft iron with insulated wire, and made it an electro-magnet, and placed the north end of the magnetized bar between the two legs of this electro-magnet. When the latter was made a magnet by the current the end of the bar thus placed was attracted by one leg of the magnet and repelled by the other, and was thus caused to swing in a horizontal plane so that the opposite end of it struck a bell. Thus was an electric telegraph made as an experimental toy, and fulfilling all the conditions of such an one giving the signals by sound, as the modern telegraph does. It lacked one thing--the essential. [Footnote: The details of the construction of the modern telegraph line are not here stated. There are none that change, in principle, the outline above given.]
The Vail telegraphic alphabet had not been thought of. Had such an idea been conceived previously a message could have been read as it is read now, and with the toy of Professor Henry which he abandoned without an idea of its utility or of the possibilities of any telegraph as we have long known them. Morse knew these possibilities. He was one of the innumerable eccentrics who have been right, one of the prophets who have been in the beginning without honor, not only in respect to their own country, but in respect to their times.
[Ill.u.s.tration: DIAGRAM OF TELEGRAPH SYSTEM.]
CHAPTER II.
THE OCEAN CABLE.--The remaining department of Telegraphy is embodied in the startling departure from ancient ideas of the possible which we know as cable telegraphy, the messages by such means being _cablegrams_.
About these ocean systems there are many features not applying to lines on land, though they are intended to perform the same functions in the same way, with the same object of conveying intelligence in language, instantly and certainly, but under the sea.
The marine cables are not simple wires. There is in the center a strand of usually seven small copper wires, intended as the conductor of the current. These, twisted loosely into a small cable, are surrounded by repeated layers of gutta-percha, which is, in turn, covered with jute.
Outside of all there is an armor of wires, and the entire cable appears much like any other of the wire cables now in common use with elevators, bridges, and for many purposes. In the shallow waters of bays and harbors, where anchors drag and the like occurrences take place, the armor of a submarine cable is sometimes so heavy as to weigh more than twenty tons to the mile.
There are peculiar difficulties encountered in sending messages by an ocean cable, and some of these grow out of the same induction whose laws are indispensable in other cases. The inner copper core sets up induction in the strands of the outer armor, and that again with the surrounding water. There is, again, a species of re-induction affecting the core, so that faint impulses may be received at the terminals that were never sent by the operators. All of these difficulties combined result in what electricians term "r.e.t.a.r.dation." It is one of the departments of telegraphy that, like the unavoidable difficulties in all machines and devices, educates men to their special care, and keeps them thinking. It is one of the natural features of all the mechanical sciences that results in the continual making of improvements.
The first impression in regard to ocean cables would be that very strong currents are used in sending impulses so far. The opposite is true. The receiving instrument is not the noisy "sounder" of the land lines. There was, until recently, a delicate needle which swung to and fro with the impulses, and reflected beams of light which, according to their number and the s.p.a.ce between them spelled out the message according to the Vail dot-and-dash alphabet. Now, however, a means still more delicate has been devised, resulting in a faint wavy ink-line on a long, unwinding slip of paper, made by a fountain pen. This strange ma.n.u.script may be regarded as the latest system of writing in the world, having no relations.h.i.+p to the art of Cadmus, and requiring an expert and a special education to decipher it. Those faint pulsations, from a hand three thousand miles away across the sea, are the realization of a magic incredible. The necromancy and black art of all antiquity are childish by comparison. They give but faint indications of what they often are--the messages of love and death; the dictations of statesmans.h.i.+p; the heralds of peace or war; the orders for the disposition of millions of dollars.
The story of the laying of the first ocean cable is worthy of the telling in any language, but should be especially interesting to the American boy and girl. It is a story of native enterprise and persistence; perhaps the most remarkable of them all.
The earliest ocean telegraph was that laid by two men named Brett, across the English Channel. For this cable, a pioneer though crossing only a narrow water, the conservative officials of the British government refused a charter. In August, 1850, they laid a single copper wire covered with gutta-percha from Dover in England to the coast of France. The first wire was soon broken, and a second was made consisting of several strands, and this last was soon imitated in various short reaches of water in Europe.
But the Atlantic had always been considered unfathomable. No line had ever sounded its depths, and its strong currents had invariably swept away the heaviest weights before they reached its bed. Its great feature, so far as known, was that strange ocean river first noted and described by Franklin, and known to us as the Gulf Stream. In 1853 a circ.u.mstance occurred which again turned the attention of a few men to the question of an Atlantic cable. Lieutenant Berryman, of the Navy, made a survey of the bottom of the Atlantic from Newfoundland to Ireland, and the wonderful discovery was made that the floor of the ocean was a vast plain, not more than two miles below the surface, extending from one continent to the other. This plain is about four hundred miles wide and sixteen hundred long, and there are no currents to disturb the ma.s.s of broken sh.e.l.ls and unknown fishes that lie on its oozy surface. It was named the "Telegraphic Plateau," with a view to its future use. At either edge of this plateau huge mountains, from four to seven thousand feet high, rise out of the depths. There are precipices of sheer descent down which the cable now hangs. The Azores and Bermudas are peaks of ocean mountains. The warm river known as the Gulf Stream, coming northward meets the ice-bergs and melts them, and deposits the sh.e.l.ls, rocks and sand they carry on this plain. When it was discovered the difficulty in the way of an Atlantic cable seemed no longer to exist, and those who had been anxious to engage in the enterprise began to bestir themselves.
Of these the most active was the American, Cyrus W. Field. He began life as a clerk in New York City. When thirty-five years old he became engaged in the building of a land line of telegraph across Newfoundland, the purpose of which was to transmit news brought by a fast line of steamers intended to be established, and the idea is said to have occurred to him of making a line not only so far, but across the sea. In November, 1856, he had succeeded in forming a company, and the entire capital, amounting to 350,000 pounds, was subscribed. The governments of England and the United States promised a subsidy to the stockholders.
The cable was made in England. The _Niagara_ was a.s.signed by the United States, and the _Agamemnon_ by England, each attended by smaller vessels, to lay the cable. In August, 1857, the Niagara left the coast of Ireland, dropping her cable into the sea. Even when it dropped suddenly down the steep escarpment to the great plateau the current still flowed. But through the carelessness of an a.s.sistant the cable parted. That was the beginning of mishaps. The task was not to be so easily done, and the enterprise was postponed until the following year.
That next year was still more memorable for triumph and disappointment.
It was now designed that the two vessels should meet in mid-ocean, unite the ends of the cable, and sail slowly to opposite sh.o.r.es. There were fearful storms. The huge _Agamemnon_, overloaded with her half of the cable, was almost lost. But finally the spot in the waste and middle of the Atlantic was reached, the sea was still, and the vessels steamed away from each other slowly uncoiling into the sea their two halves of the second cable. It parted again, and the two s.h.i.+ps returned to Ireland.
In July they again met in mid-ocean. Europe and America were both charitably deriding the splendid enterprise. All faith was lost. It was known, to journalism especially, that the cable would never be laid and that the enterprise was absurd. But it was like the laying of the first land line. There was a way to do it, existing in the brains and faith of men, though at first that way was not known. From this third meeting the two s.h.i.+ps again sailed away, the _Niagara_ for America, the _Agamemnon_ for Valencia Bay. This time the wire did not part, and on August 29th, 1858, the old world and the new were bound together for the first time, and each could read almost the thoughts of the other.
The queen saluted America, and the president replied. There were salutes of cannon and the ringing of bells. But the messages by the cable grew indistinct day by day, and finally ceased. The Atlantic cable had been laid, and--had failed.
Eight years followed, and the cable lay forgotten at the bottom of the sea. The reign of peace on earth and good will to men had so far failed to come and they were years of tumult and bitterness. The Union of the United States was called upon to defend its integrity in a great war. A bitter enmity grew up between us and England. The telegraph, and all its persevering projectors, were almost absolutely forgotten. Electricians declared the project utterly impracticable, and it began, finally, to be denied that any messages had ever crossed the Atlantic at all, and Field and his a.s.sociates were discredited. It was said that the current could not be made to pa.s.s through so long a circuit. New routes were spoken of--across Bering's Strait, and overland by way of Siberia--and measures began to be taken to carry this scheme into effect.
Amid these discouragements, Field and his a.s.sociates revived their company, made a new cable, and provided everything that science could then suggest to aid final success. This new cable was more perfect than any of the former ones, and there was a mammoth side-wheel steamer known as the _Great Eastern_, unavailable as it proved for the ordinary uses of commerce, and this vessel was large enough to carry the entire cable in her hold. In July, 1865, the huge steamer left Ireland, dropping the endless coil into the sea. The same men were engaged in this last attempt that had failed in all the previous ones. It is one of the most memorable instances of perseverance on record. But on August 6th a flaw occurred, and the cable was being drawn up for repairs. The sound of the wheel suddenly stopped; the cable broke and sunk into the depths. The _Great Eastern_ returned unsuccessful to her port.
Field was present on board on this occasion, and had been present on several similar ones. There was, so far as known, no record made by him of his thoughts. There were now five cables in the bed of the Atlantic, and each one had carried down with it a large sum of money, and a still larger sum of hopes. Yet the Great Eastern sailed again in July, 1866, her tanks filled with new cable and Field once more on her decks. It was the last, and the successful attempt. The cable sank steadily and noiselessly into the sea, and on July 26th the steamer sailed into Trinity Bay. The connection was made at Heart's Content, a little New Foundland fis.h.i.+ng village, and one for this occasion admirably named.
Then the lost cable of 1865 was found, raised and spliced.
In these later times, if a flaw should occur, science would locate it, and go and repair it. Even if this were not true, the fact remains that this last cable, and that of 1865, have been carrying their messages under the sea for nearly thirty years. The lesson is that repeated failures do not mean _final_ failure. There is often said to be a malice, a spirit of rebellion, in inanimate things. They refuse to become slaves until they are once and for all utterly subdued, and then they are docile forever. Yet the malice truly lies in the inapt.i.tude and inexperience of men. Had Field and his a.s.sociates known how to make and lay an Atlantic cable in the beginning as well as they did in the end, the first one laid would have been successful. The years were pa.s.sed in the invention of machinery for laying, and in improving the construction of each successive cable. Many have been laid since then, certainly and without failure. Men have learned how. [Footnote: At present the total mileage of submarine cables is about 152,000 miles, costing altogether $200,000,000. The length of land wires throughout the world is over 2,000,000 miles, costing $225,000,000. The capital invested in all lines, land and sea, is about $530,000,000.]
Thirteen years were pa.s.sed in this succession of toils, expenditures, trials and failures. Field crossed the Atlantic more than fifty times in these years, in pursuit of his great idea. At last, like Morse, he was crowned with wealth, success, medals and honors. He was acquainted with all the difficulties. It is now known that he knew through them all that an ocean cable could finally be laid.
THE TELEPHONE.--The telegraph had become old. All nations had become accustomed to its use. More than thirty years had elapsed--a long time in the last half of the nineteenth century--before mankind awoke to a new and startling surprise; the telegraph had been made to transmit not only language, but the human voice in articulate speech. [Footnote: It has been noted that Morse's idea was a _recording_ telegraph, that being in his mind its most valuable point, and that this idea has long been obsolete. In like manner, when the Telephone was invented there was a general business opinion that it was perhaps an instrument useful in colleges for demonstrating the wonders of electricity, but not useful for commercial purposes _because it made no record_. "Business will always be done in black and white" was the oracular verdict of prominent and experienced business men. It may be true, but a little conversation across s.p.a.ce has been found indispensable. The telephone is a remarkable business success.] The fact first became known in 1873, and was the invention of Alexander G. Bell, of Chicago.
[Ill.u.s.tration: DIAGRAM OF TELEPHONE.--THE BLAKE TRANSMITTER.]
There were several, no one knows how many, attempts to accomplish this remarkable feat previous to the success of Professor Bell. One of these was by Reis, of Frankfort, in 1860. It did not embrace any of the most valuable principles involved in what we know as the telephone, since it could not transmit _speech_. Professor Bell's first operative apparatus was accompanied by simultaneous inventions by Gray, Edison, and others. This remarkable instance of several of the great electricians of the country evolving at nearly the same time the same princ.i.p.al details of a revolutionary invention, has never been fully explained. The first rather crude and ineffective arrangements were rapidly improved by these men, and by others, prominent among whom is Blake, whose remarkable transmitter will be described presently. The best devices of these inventors were finally embodied, and in the resulting instrument we have one of the chiefest of those modern wonders whose first appearance taxed the credulity of mankind. [Footnote: There were, until a recent period, a line of statements, alleged facts and reasonings, that were incredible in proportion to intelligence. The occurrences of recent times have reversed this rule with regard to all things in the domain of applied science. It is the ignorant and narrow only who are incredulous, and the ears of intelligence are open to every sound. All that is not absurd is possible, and all that is possible is sure to be accomplished. The telephone, as a statement, _was_ absurd, but not to the men who worked for its accomplishment and finally succeeded. The lines grow narrow. It requires now a high intelligence to decide even upon the fact of absurdity within the domain of natural law.]
In reality the telephone is simple in construction. Workmen who are not accomplished electricians constantly erect, correct and repair the lines and instruments. The machine is not liable to derangement. Any person may use it the first time of trying, and this use is almost universal.
Yet it is, from the view of any hour in all the past, an incomprehensible mystery. A moment of reflection drifts the mind backward and renders it almost incredible in the present. The human voice, recognizable, in articulate words, is apparently borne for miles, now even for some hundreds of miles, upon an attenuated wire which hangs silent in the air carrying absolutely nothing more than thousands of little varying impulses of electricity. Not a word that is spoken at one end of it is ever heard at the other, and the conclusion inevitable to the reason of even twenty years ago would be that if one person does not actually hear the other talk there is a miracle. Probably this idea that the voice is actually carried is not very uncommon. The facts seem incomprehensible otherwise, and it is not considered that if that idea were correct it _would_ be a miracle.
The entire explanation of the magic of the telephone lies in electrical induction. To the brief explanation of that phenomenon previously given the reader is again referred for a better understanding of what now follows.
But, first, a moment's consideration may be given to the results produced by the use of this appliance, which, as an ill.u.s.tration of the way of the world was an innovation that, had it remained uninvented or impossible, would never have been even desired. One third more business is said now to be transacted in the average day than was possible previously. Since many things can now go on together which previously waited for direction, authority and personal arrangement, a man's business life is lengthened one-third, while his business may mostly be done, to his great convenience, from one place. It has given employment to a large number of persons, a large proportion of whom are young women. The status of woman in the business world has been, fortunately or unfortunately, by so much changed. It has introduced a new necessity, never again to be dispensed with. It has changed the ancient habits, and with them, unconsciously, _the habit of thought_. Contact not personal between man and man has increased. The _thought_ of others is quickly arrived at. It has caused us to become more appreciative of the absolute meanings and values of words, without a.s.sistance from face, manner or gesture. Laughter may be heard, but tears are unseen. It has induced caution in speech and enforces brevity. While none of its conveniences are now noted, and all that it gives is expected, the telephone, with all its effects, has entered--into the sum of life.
On the wall or table there is a box, and beside this box projects a metal arm. In a fork of this arm hangs a round, black, trumpet-shaped, hard rubber tube. This last is the receiving instrument. It is taken from its arm and held close to the ear. The answers are heard in it as though the person speaking were there concealed in an impish embodiment of himself. Meantime the talking is done into a hole in the side of the box, while the receiver is held to the ear. This is all that appears superficially. An operation incredible has its entire machinery concealed in these simplicities. It is difficult to explain the mystery of the telephone in words--though it has been said to be simple--and it is almost impossible unless the reader comprehends, or will now undertake to comprehend, what has been previously said on the subject of the production of magnetism by a current of electricity, as in the case of the electro-magnet, and on the subject of induction and its laws.
It has been shown that electricity produces magnetism; that the current, properly managed as described, creates instantly a powerful magnet out of a piece of soft iron, and leaves it again a mere piece of iron at the will of the operator. This process also will work backwards. An electric current produces a magnet, and _a magnet also may be made to produce an electric current_. It is one more of the innumerable, almost universal, cases where scientific and mechanical processes may be reversed. When the dynamo is examined this process is still further exemplified, and when we examine the dynamo and the motor together we have a striking example of the two processes going on together.
The application of this making of a current, or changing its intensity, in the telephone, is apparently totally unlike the continuous manufacture of the induced current for daily use by means of the steam engine and dynamo. But it is in exact accord with the same laws. It will, perhaps, be more readily understood by recalling the results of the experiment of the two wires, where it was found that an _approach to_, or a _receding from_, a wire carrying a current, produces an impulse over the wire that has by itself no current at all. Now, it must be added to that explanation that if the battery were detached from that conducting wire, and if, instead of its being a wire for the carrying of a battery current _it were itself a permanent magnet_, the same results would happen in the other wire if it were rapidly moved toward and away from this permanent magnet. If the reader should stretch a wire tightly between two pegs on a table, and should then hold the arms of a common horseshoe magnet very near it, and should tw.a.n.g the stretched wire with his finger, as he would a guitar string, the electrometer would show an induced alternate current in the wire. Since this is an ill.u.s.tration of the principle of the dynamo, stated in its simplest form, it may be well to remember that in this manner--with the means multiplied and in all respects made the most of--a very strong current of electricity may be evolved without any battery or other source of electricity except a magnet. In connection with this subst.i.tution of a magnet for a current-carrying wire, it must be remembered that moving the magnet toward or from the wire has the same result as moving the wire instead. It does not matter which piece is moved.
In addition to the above, it should be stated that not only will an induced current be set up in the wire, but also _the magnetism in the magnet will be increased or diminished as the tremblings of the wire cause it to approach or recede from it_. Therefore if a wire be led away from each pole of a permanent magnet, and the ends united to form a circuit, an induced current will appear in this wire if a piece of soft iron is pa.s.sed quickly near the magnet.
There is an essential part of the telephone that it is necessary to go outside of the field of electricity to describe. It is undoubtedly understood by the reader that all sound is produced by vibrations, or rapid undulations, of the surrounding air. If a membrane of any kind is stretched across a hoop, and one talks against it, so to speak, the diaphragm or membrane will be shaken, will vibrate, with the movement of the air produced by the voice. If a cannon be fired all the windows rattle, and are often broken. A peal of thunder will cause the same jar and rattle of window panes, manifestly by what we call "sound"--vibrations of the air. The window frame is a "diaphragm." The ear is constructed on the same principle, its diaphragm being actually moved by the vibrations of air, being what we call hearing. With these facts about sound understood in connection with those given in connection with the subst.i.tution of a magnet for a battery current, it is entirely possible for any non-expert to understand the theory of the construction of the telephone.
In the Bell telephone, now used with the Blake transmitter [which differs somewhat from the arrangement I shall now describe] a bar magnet has a portion of its length wound with very fine insulated wire. Across the opposite end of this polarized [Footnote: "Polarized" means magnetized; having the two poles of a permanent magnet. The term is frequently used in descriptions of electrical appliances. Instead of using the terms _positive_ and _negative_, it is also customary to speak of the "North" or the "South" of a magnet, battery or circuit.] magnet, crosswise to it, and very close, there is placed a diaphragm of thin sheet iron. This is held only around its edge, and its center is free to vibrate toward and from the end of this polarized magnet. This thin disc of iron, therefore, follows the movements, the "soundwaves," of the air against it, which are caused by the human voice. We have an instance of apiece of soft iron moving toward, and away from, a magnet. It moves with a rapidity and violence precisely proportioned to the tones and inflections of the voice. Those movements are almost microscopic, not perceptible to the eye, but sufficient.
The approaching and receding have made a difference, in the quality of the magnet. Its magnetism has been increased and diminished, and the little coil of insulated wire around it has felt these changes, and carried them as impulses over the circuit of which it is a part. In that circuit, at the other end, there is a precisely similar little insulated coil, upon a precisely similar polarized magnet. These impulses pa.s.s through this second coil, and increase or diminish the magnetism in the magnet round which it is coiled. That, in turn, affects by magnetic attraction the diaphragm that is arranged in relation to its magnet precisely as described for the first. The first being controlled as to the extent and rapidity of its movements by the loudness and other modifications of the voice, the impulses sent over the circuit vary accordingly. As a consequence, so does the strength of the magnet whose coil is also in the circuit. So, therefore, does its power of attraction over its diaphragm vary. The result is that the movements that are caused in the first diaphragm by the voice, are caused in the second by an _attraction_ that varies in strength in proportion to the vibrations of the voice speaking against the first diaphragm.
This is the theory of the telephone. The sounds are not carried, but _mechanically produced_ again by the rattle of a thin piece of iron close to the listener's ear. The voice is full, audible, distinct, as we hear it naturally, and as it impinges upon the transmitting diaphragm.
In reproduction at the receiving instrument it is small in volume; almost microscopic, if the phrase may be applied to sound. We hear it only by placing the ear close to the diaphragm. It will be seen that this is necessarily so. No attempts to remedy the difficulty have so far been successful. There is no means of reproducing the volume of the voice with the minute vibrations of a little iron disc.
In actual service an electro-magnet is used instead of, or in addition to, the bar magnets described above. A steady flow from a battery is pa.s.sed through an instrument which throws this current into proper vibrations by stopping the flow of the current at each interval between impulses. There is a piece of carbon between the diaphragm and its support. The wires are connected with the diaphragm and its support, and the current pa.s.ses through the carbon. When the diaphragm vibrates, the carbon is slightly compressed by it. Pressure reduces its resistance, and a greater current pa.s.ses through it and over the wires of the circuit for the instant during which the touch remains. This is the Blake transmitter. It should be explained that carbon stands low on the list of conductors of electricity. The more dense it is, the better conductor. The varying pressures of the diaphragm serve to produce this varying density and the consequent varying impulses of the current which effect the receiving diaphragm.
The transmitter, as above described, is in the square box, and its round black diaphragm may be seen behind the round hole into which one talks.
[Footnote: Shouting into a telephone doubtless comes of the idea, unconscious, that one is speaking to a person at a distance. To speak distinctly is better, and in an ordinary tone.] The receiver is the trumpet-shaped tube which hangs on its side, and is taken from its hook to be used. The call-bell has nothing to do with the telephone. It is operated by a small magneto-generator,--a very near relative of the dynamo-the current from which is sent over the telephone circuit (the same wires) when the small crank is turned. Sometimes the question occurs: "Why ring one's own bell when one desires to ring only that at the central office?" The answer is that both bells are in the same circuit. If the circuit is uninterrupted your bell will ring when you ring the other, and a bell at each end of your circuit is necessary in any case, else you could not yourself be called.
When the receiving instrument is on its hook its weight depresses the lever slightly. This slight movement _connects_ the bell circuit and _disconnects_ the telephone circuit. Take it off the hook and the reverse is effected.
The long-distance telephone differs from the ordinary only in larger conductors, improved instruments, and a metallic circuit--two wires instead of the ordinary single wire and ground connections.
[Ill.u.s.tration: TELEAUTOGRAPH TRANSMITTING INSTRUMENT.]
THE TELAUTOGRAPH.--This, the latest of modern miracles in the field of electricity, comes naturally after the telegraph and telephone, since it supplements them as a means of communication between individuals. It also is the invention of Prof. Elisha Gray, who seems to be as well the author of the name of his extraordinary achievement. It is not the first instrument of the kind attempted. The desire to find a means of writing at a distance is old. Bain, of Edinburgh, made a machine partially successful fifty years ago. Like the telegraph as intended by Morse, there was the interposition of typesetting before a message could be sent. It did not write, or follow the hand of the operator in writing, though it did reproduce at the other end of the circuit in facsimile the faces of the types that had been set by the sender. It was a process by electrolysis, well understood by all electricians. Several of this variety of writing telegraphs have been made, some of them almost successful, but all lacking the vital essential. [Footnote: The lack of _one vital essential_ has been fatal to hundreds of inventions.
Inventors unconsciously follow paths made by predecessors. The entire cla.s.s of transmitting instruments must dispense with tedious preliminaries, and must use _words_. Vail accomplished this in telegraphy. Bell and others in the telephone, and Gray has borne the same fact in mind in the present development of the telautograph.] In 1856 Ca.s.selli, of Florence, made a writing telegraph which had a pendulum arrangement weighing fourteen pounds. Only one was ever made, but it resulted in many new ideas all pertaining to the facsimile systems--the following of the faces of types--and all were finally abandoned.