Heroes of the Telegraph Part 9

Before he left Scotland Mr. Graham Bell had turned his attention to telephony, and in Canada he designed a piano which could transmit its music to a distance by means of electricity. At Boston he continued his researches in the same field, and endeavoured to produce a telephone which would not only send musical notes, but articulate speech.

If it be interesting to trace the evolution of an animal from its rudimentary germ through the lower phases to the perfect organism, it is almost as interesting to follow an invention from the original model through the faultier types to the finished apparatus.

In 1860 Philipp Reis, as we have seen, produced a telephone which could transmit musical notes, and even a lisping word or two; and some ten years later Mr. Cromwell Fleetwood Varley, F.R.S., a well-known English electrician, patented a number of ingenious devices for applying the musical telephone to transmit messages by dividing the notes into short or long signals, after the Morse code, which could be interpreted by the ear or by the eye in causing them to mark a moving paper. These inventions were not put in practice; but four years afterwards Herr Paul la Cour, a Danish inventor, experimented with a similar appliance on a line of telegraph between Copenhagen and Fredericia in Jutland. In this a vibrating tuning-fork interrupted the current, which, after traversing the line, pa.s.sed through an electro-magnet, and attracted the limbs of another fork, making it strike a note like the transmitting fork. By breaking up the note at the sending station with a signalling key, the message was heard as a series of long and short hums. Moreover, the hums were made to record themselves on paper by turning the electro-magnetic receiver into a relay, which actuated a Morse printer by means of a local battery.

Mr. Elisha Gray, of Chicago, also devised a tone telegraph of this kind about the same time as Herr La Cour. In this apparatus a vibrating steel tongue interrupted the current, which at the other end of the line pa.s.sed through the electro-magnet and vibrated a band or tongue of iron near its poles. Gray's 'harmonic telegraph,' with the vibrating tongues or reeds, was afterwards introduced on the lines of the Western Union Telegraph Company in America. As more than one set of vibrations--that is to say, more than one note--can be sent over the same wire simultaneously, it is utilised as a 'multiplex' or many-ply telegraph, conveying several messages through the same wire at once; and these can either be interpreted by the sound, or the marks drawn on a ribbon of travelling paper by a Morse recorder.

Gray also invented a 'physiological receiver,' which has a curious history. Early in 1874 his nephew was playing with a small induction coil, and, having connected one end of the secondary circuit to the zinc lining of a bath, which was dry, he was holding the other end in his left hand. While he rubbed the zinc with his right hand Gray noticed that a sound proceeded from it, which had the pitch and quality of the note emitted by the vibrating contact or electrotome of the coil. 'I immediately took the electrode in my hand,' he writes, 'and, repeating the operation, found to my astonishment that by rubbing hard and rapidly I could make a much louder sound than the electrotome. I then changed the pitch of the vibration, and found that the pitch of the sound under my hand was also changed, agreeing with that of the vibration.'

Gray lost no time in applying this chance discovery by designing the physiological receiver, which consists of a sounding-box having a zinc face and mounted on an axle, so that it can be revolved by a handle. One wire of the circuit is connected to the revolving zinc, and the other wire is connected to the finger which rubs on the zinc. The sounds are quite distinct, and would seem to be produced by a microphonic action between the skin and the metal.

All these apparatus follow in the track of Reis and Bourseul--that is to say, the interruption of the current by a vibrating contact. It was fortunate for Bell that in working with his musical telephone an accident drove him into a new path, which ultimately brought him to the invention of a speaking telephone. He began his researches in 1874 with a musical telephone, in which he employed the interrupted current to vibrate the receiver, which consisted of an electro-magnet causing an iron reed or tongue to vibrate; but, while trying it one day with his a.s.sistant, Mr. Thomas A. Watson, it was found that a reed failed to respond to the intermittent current. Mr. Bell desired his a.s.sistant, who was at the other end of the line, to pluck the reed, thinking it had stuck to the pole of the magnet. Mr. Watson complied, and to his astonishment Bell observed that the corresponding reed at his end of the line thereupon began to vibrate and emit the same note, although there was no interrupted current to make it. A few experiments soon showed that his reed had been set in vibration by the magneto-electric currents induced in the line by the mere motion of the distant reed in the neighbourhood of its magnet. This discovery led him to discard the battery current altogether and rely upon the magneto-induction currents of the reeds themselves. Moreover, it occurred to him that, since the circuit was never broken, all the complex vibrations of speech might be converted into sympathetic currents, which in turn would reproduce the speech at a distance.

Reis had seen that an undulatory current was needed to transmit sounds in perfection, especially vocal sounds; but his mode of producing the undulations was defective from a mechanical and electrical point of view. By forming 'waves' of magnetic disturbance near a coil of wire, Professor Bell could generate corresponding waves of electricity in the line so delicate and continuous that all the modulations of sound could be reproduced at a distance.

As Professor of Vocal Physiology in the University of Boston, he was engaged in training teachers in the art of instructing deaf mutes how to speak, and experimented with the Leon Scott phonautograph in recording the vibrations of speech. This apparatus consists essentially of a thin membrane vibrated by the voice and carrying a light stylus, which traces an undulatory line on a plate of smoked gla.s.s. The line is a graphic representation of the vibrations of the membrane and the waves of sound in the air.

On the suggestion of Dr. Clarence J. Blake, an eminent Boston aurist, Professor Bell abandoned the phonautograph for the human ear, which it resembled; and, having removed the stapes bone, moistened the drum with glycerine and water, attached a stylus of hay to the nicus or anvil, and obtained a beautiful series of curves in imitation of the vocal sounds.

The disproportion between the slight ma.s.s of the drum and the bones it actuated, is said to have suggested to him the employment of goldbeater's skin as membrane in his speaking telephone. Be this as it may, he devised a receiver, consisting of a stretched diaphragm or drum of this material having an armature of magnetised iron attached to its middle, and free to vibrate in front of the pole of an electro-magnet in circuit with the line.

This apparatus was completed on June 2, 1875, and the same day he succeeded in transmitting SOUNDS and audible signals by magneto-electric currents and without the aid of a battery. On July 1, 1875, he instructed his a.s.sistant to make a second membrane-receiver which could be used with the first, and a few days later they were tried together, one at each end of the line, which ran from a room in the inventor's house at Boston to the cellar underneath. Bell, in the room, held one instrument in his hands, while Watson in the cellar listened at the other. The inventor spoke into his instrument, 'Do you understand what I say?' and we can imagine his delight when Mr. Watson rushed into the room, under the influence of his excitement, and answered,'Yes.'

A finished instrument was then made, having a transmitter formed of a double electro-magnet, in front of which a membrane, stretched on a ring, carried an oblong piece of soft iron cemented to its middle. A mouthpiece before the diaphragm directed the sounds upon it, and as it vibrated with them, the soft iron 'armature' induced corresponding currents in the cells of the electro-magnet. These currents after traversing the line were pa.s.sed through the receiver, which consisted of a tubular electro-magnet, having one end partially closed by a thin circular disc of soft iron fixed at one point to the end of the tube.

This receiver bore a resemblance to a cylindrical metal box with thick sides, having a thin iron lid fastened to its mouth by a single screw.

When the undulatory current pa.s.sed through the coil of this magnet, the disc, or armature-lid, was put into vibration and the sounds evolved from it.

The apparatus was exhibited at the Centennial Exhibition, Philadelphia, in 1876, and at the meeting of the British a.s.sociation in Glasgow, during the autumn of that year, Sir William Thomson revealed its existence to the European public. In describing his visit to the Exhibition, he went on to say: 'In the Canadian department I heard, "To be or not to be... there's the rub," through an electric wire; but, scorning monosyllables, the electric articulation rose to higher flights, and gave me pa.s.sages taken at random from the New York newspapers: "s.s. c.o.x has arrived" (I failed to make out the s.s. c.o.x); "The City of New York," "Senator Morton," "The Senate has resolved to print a thousand extra copies," "The Americans in London have resolved to celebrate the coming Fourth of July!" All this my own ears heard spoken to me with unmistakable distinctness by the then circular disc armature of just such another little electro-magnet as this I hold in my hand.'

To hear the immortal words of Shakespeare uttered by the small inanimate voice which had been given to the world must indeed have been a rare delight to the ardent soul of the great electrician.

The surprise created among the public at large by this unexpected communication will be readily remembered. Except one or two inventors, n.o.body had ever dreamed of a telegraph that could actually speak, any more than they had ever fancied one that could see or feel; and imagination grew busy in picturing the outcome of it. Since it was practically equivalent to a limitless extension of the vocal powers, the ingenious journalist soon conjured up an infinity of uses for the telephone, and hailed the approaching time when ocean-parted friends would be able to whisper to one another under the roaring billows of the Atlantic. Curiosity, however, was not fully satisfied until Professor Bell, the inventor of the instrument, himself showed it to British audiences, and received the enthusiastic applause of his admiring countrymen.

The primitive telephone has been greatly improved, the double electro-magnet being replaced by a single bar magnet having a small coil or bobbin of fine wire surrounding one pole, in front of which a thin disc of ferrotype is fixed in a circular mouthpiece, and serves as a combined membrane and armature. On speaking into the mouthpiece, the iron diaphragm vibrates with the voice in the magnetic field of the pole, and thereby excites the undulatory currents in the coil, which, after travelling through the wire to the distant place, are received in an identical apparatus. [This form was patented January 30, 1877.] In traversing the coil of the latter they reinforce or weaken the magnetism of the pole, and thus make the disc armature vibrate so as to give out a mimesis of the original voice. The sounds are small and elfin, a minim of speech, and only to be heard when the ear is close to the mouthpiece, but they are remarkably distinct, and, in spite of a disguising tw.a.n.g, due to the fundamental note of the disc itself, it is easy to recognise the speaker.

This later form was publicly exhibited on May 4, 1877 at a lecture given by Professor Bell in the Boston Music Hall. 'Going to the small telephone box with its slender wire attachments,' says a report, 'Mr.

Bell coolly asked, as though addressing some one in an adjoining room, "Mr. Watson, are you ready!" Mr. Watson, five miles away in Somerville, promptly answered in the affirmative, and soon was heard a voice singing "America."....Going to another instrument, connected by wire with Providence, forty-three miles distant, Mr. Bell listened a moment, and said, "Signor Brignolli, who is a.s.sisting at a concert in Providence Music Hall, will now sing for us." In a moment the cadence of the tenor's voice rose and fell, the sound being faint, sometimes lost, and then again audible. Later, a cornet solo played in Somerville was very distinctly heard. Still later, a three-part song floated over the wire from the Somerville terminus, and Mr. Bell amused his audience exceedingly by exclaiming, "I will switch off the song from one part of the room to another, so that all can hear." At a subsequent lecture in Salem, Ma.s.sachusetts, communication was established with Boston, eighteen miles distant, and Mr. Watson at the latter place sang "Auld Lang Syne," the National Anthem, and "Hail Columbia," while the audience at Salem joined in the chorus.'

Bell had overcome the difficulty which baffled Reis, and succeeded in making the undulations of the current fit the vibrations of the voice as a glove will fit the hand. But the articulation, though distinct, was feeble, and it remained for Edison, by inventing the carbon transmitter, and Hughes, by discovering the microphone, to render the telephone the useful and widespread apparatus which we see it now.

Bell patented his speaking telephone in the United States at the beginning of 1876, and by a strange coincidence, Mr. Elisha Gray applied on the same day for another patent of a similar kind. Gray's transmitter is supposed to have been suggested by the very old device known as the 'lovers' telephone,' in which two diaphragms are joined by a taut string, and in speaking against one the voice is conveyed through the string, solely by mechanical vibration, to the other. Gray employed electricity, and varied the strength of the current in conformity with the voice by causing the diaphragm in vibrating to dip a metal probe attached to its centre more or less deep into a well of conducting liquid in circuit with the line. As the current pa.s.sed from the probe through the liquid to the line a greater or less thickness of liquid intervened as the probe vibrated up and down, and thus the strength of the current was regulated by the resistance offered to the pa.s.sage of the current. His receiver was an electro-magnet having an iron plate as an armature capable of vibrating under the attractions of the varying current. But Gray allowed his idea to slumber, whereas Bell continued to perfect his apparatus. However, when Bell achieved an unmistakable success, Gray brought a suit against him, which resulted in a compromise, one public company acquiring both patents.

Bell's invention has been contested over and over again, and more than one claimant for the honour and reward of being the original inventor of the telephone have appeared. The most interesting case was that of Signor Antonio Meucci, an Italian emigrant, who produced a ma.s.s of evidence to show that in 1849, while in Havanna, Cuba, he experimented with the view of transmitting speech by the electric current. He continued his researches in 1852-3, and subsequently at Staten Island, U.S.; and in 1860 deputed a friend visiting Europe to interest people in his invention. In 1871 he filed a caveat in the United States Patent Office, and tried to get Mr. Grant, President of the New York District Telegraph Company, to give the apparatus a trial. Ill-health and poverty, consequent on an injury due to an explosion on board the Staten Island ferry boat Westfield, r.e.t.a.r.ded his experiments, and prevented him from completing his patent. Meucci's experimental apparatus was exhibited at the Philadelphia Exhibition of 1884, and attracted much attention. But the evidence he adduces in support of His early claims is that of persons ignorant of electrical science, and the model shown was not complete. The caveat of 1871 is indeed a reliable doc.u.ment; but unfortunately for him it is not quite clear from it whether he employed a 'lovers' telephone,' with a wire instead of a string, and joined a battery to it in the hope of enhancing the effect. 'I employ,' he says, 'the well known conducting effect of continuous metallic conductors as a medium for sound, and increase the effect by electrically insulating both the conductor and the parties who are communicating. It forms a speaking telegraph without the necessity of any hollow tube.' In connection with the telephone he used an electric alarm. It is by no means evident from this description that Meucci had devised a practicable speaking telephone; but he may have been the first to employ electricity in connection with the transmission of speech. [Meucci is dead.]

'This crowning marvel of the electric telegraph,' as Sir William Thomson happily expressed it, was followed by another invention in some respects even more remarkable. During the winter of 1878 Professor Bell was in England, and while lecturing at the Royal Inst.i.tution, London, he conceived the idea of the photophone. It was known that crystalline selenium is a substance peculiarly sensitive to light, for when a ray strikes it an electric current pa.s.ses far more easily through it than if it were kept in the dark. It therefore occurred to Professor Bell that if a telephone were connected in circuit with the current, and the ray of light falling on the selenium was eclipsed by means of the vibrations of sound, the current would undulate in keeping with the light, and the telephone would emit a corresponding note. In this way it might be literally possible 'to hear a shadow fall athwart the stillness.'

He was not the first to entertain the idea, for in the summer of 1878, one 'L. F. W.,' writing from Kew on June 3 to the scientific journal NATURE describes an arrangement of the kind. To Professor Bell, in conjunction with Mr. Summer Tainter, belongs the honour of having, by dint of patient thought and labour, brought the photophone into material existence. By constructing sensitive selenium cells through which the current pa.s.sed, then directing a powerful beam of light upon them, and occulting it by a rotary screen, he was able to vary the strength of the current in such a manner as to elicit musical tones from the telephone in circuit with the cells. Moreover, by reflecting the beam from a mirror upon the cells, and vibrating the mirror by the action of the voice, he was able to reproduce the spoken words in the telephone. In both cases the only connecting line between the transmitting screen or mirror and the receiving cells and telephone was the ray of light. With this apparatus, which reminds us of the invocation to Apollo in the MARTYR OF ANTIOCH--

'Lord of the speaking lyre, That with a touch of fire Strik'st music which delays the charmed spheres.'

Professor Bell has accomplished the curious feat of speaking along a beam of suns.h.i.+ne 830 feet long. The apparatus consisted of a transmitter with a mouthpiece, conveying the sound of the voice to a silvered diaphragm or mirror, which reflected the vibratory beam through a lens towards the selenium receiver, which was simply a parabolic reflector, in the focus of which was placed the selenium cells connected in circuit with a battery and a pair of telephones, one for each ear.

The transmitter was placed in the top of the Franklin schoolhouse, at Was.h.i.+ngton, and the receiver in the window of Professor Bell's laboratory in L Street. 'It was impossible,' says the inventor, 'to converse by word of mouth across that distance; and while I was observing Mr. Tainter, on the top of the schoolhouse, almost blinded by the light which was coming in at the window of my laboratory, and vainly trying to understand the gestures he was making to me at that great distance, the thought occurred to me to listen to the telephones connected with the selenium receiver. Mr. Tainter saw me disappear from the window, and at once spoke to the transmitter. I heard him distinctly say, "Mr. Bell, if you hear what I say, come to the window and wave your hat!" It is needless to say with what gusto I obeyed.'

The spectroscope has demonstrated the truth of the poet, who said that 'light is the voice of the stars,' and we have it on the authority of Professor Bell and M. Janssen, the celebrated astronomer, that the changing brightness of the photosphere, as produced by solar hurricanes, has produced a feeble echo in the photophone.

Pursuing these researches, Professor Bell discovered that not only the selenium cell, but simple discs of wood, gla.s.s, metal, ivory, india-rubber, and so on, yielded a distinct note when the intermittent ray of light fell upon them. Crystals of sulphate of copper, chips of pine, and even tobacco-smoke, in a test-tube held before the beam, emitted a musical tone. With a thin disc of vulcanite as receiver, the dark heat rays which pa.s.s through an opaque screen were found to yield a note. Even the outer ear is itself a receiver, for when the intermittent beam is focussed in the cavity a faint musical tone is heard.

Another research of Professor Bell was that in which he undertook to localise the a.s.sa.s.sin's bullet in the body of the lamented President Garfield. In 1879 Professor Hughes brought out his beautiful induction balance, and the following year Professor Bell, who had already worked in the same field, consulted him by telegraph as to the best mode of applying the balance to determining the place of the bullet, which had hitherto escaped the probes of the President's physicians. Professor Hughes advised him by telegraph, and with this and other a.s.sistance an apparatus was devised which indicated the locality of the ball. A full account of his experiments was given in a paper read before the American a.s.sociation for the Advancement of Science in August, 1882.

Professor Bell continues to reside in the United States, of which he is a naturalised citizen. He is married to a daughter of Mr. Gardiner G.

Hubbard, who in 1860, when she was four years of age, lost her hearing by an illness, but has learned to converse by the Horace-Mann system of watching the lips. Both he and his father-in-law (who had a pecuniary interest in his patents) have made princely fortunes by the introduction of the telephone.

CHAPTER IX. THOMAS ALVA EDISON.

Thomas Alva Edison, the most famous inventor of his time and country, was born at Milan, Erie County, Ohio, in the United States, on February 11, 1847. His pedigree has been traced for two centuries to a family of prosperous millers in Holland, some of whom emigrated to America in 1730. Thomas, his great-grandfather, was an officer of a bank in Manhattan Island during the Revolution, and his signature is extant on the old notes of the American currency. Longevity seems a characteristic of the strain, for Thomas lived to the patriarchal term of 102, his son to 103, and Samuel, the father of the inventor, is, we understand, a brisk and hale old man of eighty-six.

Born at Digby, in the county of Annapolis, Nova Scotia, on August 16, 1804, Samuel was apprenticed to a tailor, but in his manhood he forsook the needle to engage in the lumber trade, and afterwards in grain. He resided for a time in Canada, where, at Vienna, he was married to Miss Nancy Elliott, a popular teacher in the high school. She was of Scotch descent, and born in Chenango County, New York, on January 10, 1810.

After his marriage he removed, in 1837, to Detroit, Michigan, and the following year settled in Milan.

In his younger days Samuel Edison was a man of fine appearance. He stood 6 feet 2 inches in his stockings, and even at the age of sixty-four he was known to outjump 260 soldiers of a regiment quartered at Fort Gratiot, in Michigan. His wife was a fine-looking woman, intelligent, well-educated, and a social favourite. The inventor probably draws his physical endurance from his father, and his intellect from his mother.

Milan is situated on the Huron River, about ten miles from the lake, and was then a rising town of 3,000 inhabitants, mostly occupied with the grain and timber trade. Mr. Edison dwelt in a plain cottage with a low fence in front, which stood beside the roadway under the shade of one or two trees.

The child was neither pale nor prematurely thoughtful; he was rosy-cheeked, laughing, and chubby. He liked to ramble in the woods, or play on the banks of the river, and could repeat the songs of the boatmen ere he was five years old. Still he was fond of building little roads with planks, and scooping out ca.n.a.ls or caverns in the sand.

An amusing anecdote is imputed to his sister, Mrs. Homer Page, of Milan.

Having been told one day that a goose hatches her goslings by the warmth of her body, the child was missed, and subsequently found in the barn curled up in a nest beside a quant.i.ty of eggs!

The Lake Sh.o.r.e Railway having injured the trade of Milan, the family removed to Port Huron, in Michigan, when Edison was about seven years old. Here they lived in an old-fas.h.i.+oned white frame-house, surrounded by a grove, and commanding a fine view of the broad river, with the Canadian hills beyond. His mother undertook his education, and with the exception of two months he never went to school. She directed his opening mind to the acquisition of knowledge, and often read aloud to the family in the evening. She and her son were a loving pair, and it is pleasant to know that although she died on April 9, 1871, before he finally emerged from his difficulties, her end was brightened by the first rays of his coming glory.

Mr. Edison tells us that his son never had any boyhood in the ordinary sense, his early playthings being steam-engines and the mechanical powers. But it is like enough that he trapped a wood-chuck now and then, or caught a white-fish with the rest.

He was greedy of knowledge, and by the age of ten had read the PENNY ENCYCLOPAEDIA; Hume's HISTORY OF ENGLAND; Dubigne's HISTORY OF THE REFORMATION; Gibbon's DECLINE AND FALL OF THE ROMAN EMPIRE, and Sears'

HISTORY OF THE WORLD. His father, we are told, encouraged his love of study by making him a small present for every book he read.

At the age of twelve he became a train-boy, or vendor of candy, fruit, and journals to the pa.s.sengers on the Grand Trunk Railway, between Port Huron and Detroit. The post enabled him to sleep at home, and to extend his reading by the public library at Detroit. Like the boy Ampere, he proposed, it is said, to master the whole collection, shelf by shelf, and worked his way through fifteen feet of the bottom one before he began to select his fare.

Even the PRINCIPIA of Newton never daunted him; and if he did not understand the problems which have puzzled some of the greatest minds, he read them religiously, and pressed on. Burton's ANATOMY OF MELANCHOLY, Ure's DICTIONARY OF CHEMISTRY, did not come amiss; but in Victor Hugo's LES MISERABLES and THE TOILERS OF THE SEA he found a treasure after his own heart. Like Ampere, too, he was noted for a memory which retained many of the facts thus impressed upon it, as the sounds are printed on a phonogram.

The boy student was also a keen man of business, and his pursuit of knowledge in the evening did not sap his enterprises of the day. He soon acquired a virtual monopoly for the sale of newspapers on the line, and employed four boy a.s.sistants. His annual profits amounted to about 500 dollars, which were a substantial aid to his parents. To increase the sale of his papers, he telegraphed the headings of the war news to the stations in advance of the trains, and placarded them to tempt the pa.s.sengers. Ere long he conceived the plan of publis.h.i.+ng a newspaper of his own. Having bought a quant.i.ty of old type at the office of the DETROIT FREE PRESS, he installed it in a spingless car, or 'caboose' of the train meant for a smoking-room, but too uninviting to be much used by the pa.s.sengers. Here he set the type, and printed a smallsheet about a foot square by pressing it with his hand. The GRAND TRUNK HERALD, as he called it, was a weekly organ, price three cents, containing a variety of local news, and gossip of the line. It was probably the only journal ever published on a railway train; at all events with a boy for editor and staff, printer and 'devil,' publisher and hawker. Mr. Robert Stephenson, then building the tubular bridge at Montreal, was taken with the venture, and ordered an extra edition for his own use. The London TIMES correspondent also noticed the paper as a curiosity of journalism.

This was a foretaste of notoriety.

Unluckily, however, the boy did not keep his scientific and literary work apart, and the smoking-car was transformed into a laboratory as well as a printing house.

Having procured a copy of Fresenius' QUALITIVE a.n.a.lYSIS and some old chemical gear; he proceeded to improve his leisure by making experiments. One day, through an extra jolt of the car, a bottle of phosphorus broke on the floor, and the car took fire. The incensed conductor of the train, after boxing his ears, evicted him with all his chattels.

Finding an asylum in the bas.e.m.e.nt of his father's house (where he took the precaution to label all his bottles 'poison'), he began the publication of a new and better journal, ent.i.tled the PAUL PRY. It boasted of several contributors and a list of regular subscribers.

One of these (Mr. J.H.B.), while smarting under what he considered a malicious libel, met the editor one day on the brink of the St. Clair, and taking the law into his own hands, soused him in the river. The editor avenged his insulted dignity by excluding the subscriber's name from the pages of the PAUL PRY.