THE BIRTH OF THE TELEPHONE

Alexander Graham Bell had not resided at the Sanderses’ home very long before he had fitted the basement up as a workshop. For three years he haunted it, spending all of his leisure time in his experiments. Here he had his apparatus, and the basement was littered with a curious combination of electrical and acoustical devices magnets, batteries, coils of wire, tuning-forks, speaking-trumpets, etc. Bell had a great horror that his ideas might be stolen and was very nervous over any possible intrusion into his precious workshop. Only the members of the Sanders family were allowed to enter the basement. He was equally cautious in purchasing supplies and equipment lest his very purchases reveal the nature of his experiments. He would go to a half-dozen different stores for as many articles. He usually selected the night for his experiments, and pounded and scraped away indefatigably, oblivious of the fact that the family, as well as himself, was sorely in need of rest.

“Bell would often awaken me in the middle of the night,” says Mr. Sanders, “his black eyes blazing with excitement. Leaving me to go down to the cellar, he would rush wildly to the barn and begin to send me signals along his experimental wires. If I noticed any improvement in his apparatus he would be delighted. He would leap and whirl around in one of his ‘war-dances,’ and then go contentedly to bed. But if the experiment was a failure he would go back to his work-bench to try some different plan.”

In common with other experimenters who were searching for the telephone, Bell was experimenting with a sort of musical telegraph. Eagerly and persistently he sought the means that would replace the telegraph with its cumbersome signals by a new device which would enable the human voice itself to be transmitted. The longer he worked the greater did the difficulties appear. His work with the deaf and dumb was alluring, and on many occasions he seriously considered giving over his other experiments and devoting himself entirely to the instruction of the deaf and dumb and to the development of his system of making speech visible by making the sound-vibrations visible to the eye. But as he mused over the difficulties in enabling a deaf mute to achieve speech nothing else seemed impossible. “If I can make a deaf mute talk,” said Bell, “I can make iron talk.”

One of his early ideas was to install a harp at one end of the wire and a speaking-trumpet at the other. His plan was to transmit the vibrations over the wire and have the voice reproduced by the vibrations of the strings of the harp. By attaching a light pencil or marker to a cord or membrane and causing the latter to vibrate by talking against it, he could secure tracings of the sound-vibrations. Different tracings were secured from different sounds. He thus sought to teach the deaf to speak by sight.

At this time Bell enjoyed the friendship of Dr. Clarence J. Blake, an eminent Boston aurist, who suggested that the experiments be conducted with a human ear instead of with a mechanical apparatus in imitation of the ear. Bell eagerly accepted the idea, and Doctor Blake provided him with an ear and connecting organs cut from a dead man’s head. Bell soon had the ghastly specimen set up in his workshop. He moistened the drum with glycerine and water and, substituting a stylus of hay for the stapes bone, he obtained a wonderful series of curves which showed the vibrations of the human voice as recorded by the ear. One can scarce imagine a stranger picture than Bell must have presented in the conduct of those experiments. We can almost see him with his face the paler in contrast with his black hair and flashing black eyes as he shouted and whispered by turns into the ghastly ear. Surely he must have looked the madman, and it is perhaps fortunate that he was not observed by impressionable members of the public else they would have been convinced that the witches had again visited old Salem town to ply their magic anew. But it was a new and very real and practical sort of magic which was being worked there.

His experiments with the dead man’s ear brought to Bell at least one important idea. He noted that, though the ear-drum was thin and light, it was capable of sending vibrations through the heavy bones that lay back of it. And so he thought of using iron disks or membranes to serve the purpose of the drum in the ear and arrange them so that they would vibrate an iron rod. He thought of connecting two such instruments with an electrified wire, one of which would receive the sound-vibrations and the other of which would reproduce them after they had been transmitted along the wire. At last the experimenter was on the right track, with a conception of a practicable method of transmitting sound. He now possessed a theoretical knowledge of what the telephone he sought should be, but there yet remained before him the enormous task of devising and constructing the apparatus which would carry out the idea, and find the best way of utilizing the electrical current for this work.

Bell was now at a critical point in his career and was confronted by the same difficulty which assails so many inventors. In his constant efforts to achieve a telephone he had entirely neglected his school of vocal physiology, which was now abandoned. Georgie Sanders and Mabel Hubbard were his only pupils. Though Sanders and Hubbard were genuinely interested in Bell and his work, they felt that he was impractical, and were especially convinced that his experiments with the ear and its imitations were entirely useless. They believed that the electrical telegraph alone presented possibilities, and they told Bell that unless he would devote himself entirely to the improvement of this instrument and cease wasting time and money over ear toys that had no commercial value they would no longer give him financial support. Hubbard went even further, and insisted that if Bell did not abandon his foolish notions he could not marry his daughter.

Bell was almost without funds, his closest friends now seemed to turn upon him, and altogether he was in a sorry plight. Of course Sanders and Hubbard meant the best, yet in reality they were seeking to drive their protege in exactly the wrong direction. As far back as 1860 a German scientist named Philipp Reis produced a musical telephone that even transmitted a few imperfect words. But it would not talk successfully. Others had followed in his footsteps, using the musical telephone to transmit messages with the Morse code by means of long and short hums. Elisha Gray, of Chicago, also experimented with the musical telegraph. At the transmitting end a vibrating steel tongue served to interrupt the electric current which passed over the wire in waves, and, passing through the coils of an electro-magnet at the receiving end, caused another strip of steel located near the magnet to vibrate and so produce a tone which varied with the current.

All of these developments depended upon the interruption of the current by some kind of a vibrating contact. The limitations which Sanders and Hubbard sought to impose upon Bell, had they been obeyed to the letter, must have prevented his ultimate success. In a letter to his mother at this time, he said:

I am now beginning to realize the cares and anxieties of being an inventor. I have had to put off all pupils and classes, for flesh and blood could not stand much longer such a strain as I have had upon me.

But good fortune was destined to come to Bell along with the bad. On an enforced trip to Washington to consult his patent attorney a trip he could scarce raise funds to make Bell met Prof. Joseph Henry. We have seen the part which this eminent scientist had played in the development of the telegraph. Now he was destined to aid Bell, as he had aided Morse a generation earlier. The two men spent a day over the apparatus which Bell had with him. Though Professor Henry was fifty years his senior and the leading scientist in America, the youth was able to demonstrate that he had made a real discovery.

“You are in possession of the germ of a great invention,” said Henry, “and I would advise you to work at it until you have made it complete.”

“But,” replied Bell, “I have not got the electrical knowledge that is necessary.”

“Get it,” was Henry’s reply.

This proved just the stimulus Bell needed, and he returned to Boston with a new determination to perfect his great idea.

Bell was no longer experimenting in the Sanderses’ cellar, having rented a room in Boston in which to carry on his work. He had also secured the services of an assistant, one Thomas Watson, who received nine dollars a week for his services in Bell’s behalf. The funds for this work were supplied by Sanders and Hubbard jointly, but they insisted that Bell should continue his experiments with the musical telegraph. Though he was convinced that the opportunities lay in the field of telephony, Bell labored faithfully for regular periods with the devices in which his patrons were interested. The remainder of his time and energy he put upon the telephone. The basis of his telephone was still the disk or diaphragm which would vibrate when the sound-waves of the voice were thrown against it. Behind this were mounted various kinds of electro-magnets in series with the electrified wire over which the inventor hoped to send his messages. For three years they labored with this apparatus, trying every conceivable sort of disk. It is easy to pass over those three years, filled as they were with unceasing toil and patient effort, because they were drab years when little of interest occurred. But these were the years when Bell and Watson were “going to school,” learning how to apply electricity to this new use, striving to make their apparatus talk. How dreary and trying these years must have been for the experimenters we may well imagine. It requires no slight force of will to hold oneself to such a task in the face of failure after failure.

By June of 1875 Bell had completed a new Instrument. In this the diaphragm was a piece of gold-beater’s skin, which Bell had selected as most closely resembling the drum in the human ear. This was stretched tight to form a sort of drum, and an armature of magnetized iron was fastened to its middle. Thus the bit of iron was free to vibrate, and opposite it was an electro-magnet through which flowed the current that passed over the line. This acted as the receiver. At the other end of the wire was a sort of crude harmonica with a clock spring, reed, and magnet. Bell and Watson had been working upon their crude apparatus for months, and finally, on June 2d, sounds were actually transmitted. Bell was afire with enthusiasm; the first great step had been taken. The electric current had carried sound-vibrations along the wire and had reproduced them. If this could be done a telephone which would reproduce whole words and sentences could be attained.

So great was Bell’s enthusiasm over this achievement that he succeeded in convincing Sanders and Hubbard that his idea was practical, and they at last agreed to finance him in his further experiments with the telephone. A second membrane receiver was constructed, and for many more weeks the experiments continued. It was found that sounds were carried from instrument to instrument, but as a telephone they were still far from perfection. It was not until March of 1876 that Bell, speaking into the instrument in the workroom, was heard and understood by Watson at the other instrument in the basement. The telephone had carried and delivered an intelligible message.

The telephone which Bell had invented, and on which he received a patent on his twenty-ninth birthday, consisted of two instruments similar in principle to what we would now call receivers. If you will experiment with the receiver of a modern telephone you will find that it will transmit as well as receive sound. The heart of the transmitter was an electro-magnet in front of which was a drum-like membrane with a piece of iron cemented to its center opposite the magnet. A mouthpiece was arranged to throw the sounds of the voice against the diaphragm, and as the membrane vibrated the bit of iron upon it acting as an armature induced currents corresponding to the sound-waves, in the coils of the electro-magnet.

Passing over the line the current entered the coils of the tubular electro-magnet in the receiver. A thin disk of soft iron was fastened at the end of this. When the current-waves passed through the coils of the magnet the iron disk was thrown into vibration, thus producing sound. As it vibrated with the current produced by the iron on the vibrating membrane in the transmitter acting as an armature, transmitter and receiver vibrated in unison and so the same sound was given off by the receiver and made audible to the human ear as was thrown against the membrane of the transmitter by the voice.

The patent issued to Bell has been described as “the most valuable single patent ever issued.” Certainly it was destined to be of tremendous service to civilization. It was so entirely new and original that Bell found difficulty in finding terms in which to describe his invention to the patent officials. He called it “an improvement on the telegraph,” in order that it might be identified as an improvement in transmitting intelligence by electricity. In reality the telephone was very far from being a telegraph or anything in the nature of a telegraph.

As Bell himself stated, his success was in large part due to the fact that he had approached the problem from the viewpoint of an expert in sound rather than as an electrician. “Had I known more about electricity and less about sound,” he said, “I would never have invented the telephone.” As we have seen, those electricians who worked from the viewpoint of the telegraph never got beyond the limitations of the instrument and found that with it they could transmit signals but not sounds. Bell, with his knowledge of the laws of speech and sound, started with the principles of the transmission of sound as a basis and set electricity to carrying the sound-vibrations.