On the afternoon of June 2, 1875, two young men bent over work benches in the hot and stifling garret of a five-story brick building occupied by the electrical workshops of Charles Williams, at 109 Court Street, Boston. They did not speak to one another, for they were in separate rooms some sixty feet apart, at opposite ends of the floor. Between the rooms ran a length of wire.

The younger of the two men was Thomas A. Watson, twenty-one years old, a native of Salem who had left school at the age of thirteen but had become, during several years of employment at the workshop, an able and imaginative technician. His skill had been tested in the construction of virtually all the devices required by Williams’ clients—call bells, telegraph keys, galvanometers, annunciators, relays, sounders. He had, moreover, read nearly all of the few books on electricity then available, in the morning of the electrical age. His fingers were deft, his intelligence keen.

The man at the other end of the wire was a tall, rather pale, dark-haired, brown-bearded amateur inventor named Alexander Graham Bell. He was twenty-eight years and three months old. Unlike his collaborator, he had no connection with the Williams workshop. He was, in fact, a teacher of the deaf and a specialist in training teachers of the deaf. He held the title of professor of vocal physiology at Boston University. But for more than a year he had been working with Watson on an invention that he called a “harmonic telegraph.” And he had been thinking about it for more than a decade.

The purpose of Bell’s harmonic telegraph was to make possible the transmission of several messages over a single telegraph wire at the same time without interference. Thirty-one years had elapsed since Samuel F. B. Morse sent his famous message, “What hath God wrought,” over the world’s first telegraph circuit, between Washington and Baltimore. During that interval wires had spread like spider webs across the face of the land, and in 1866 the first successful submarine cable spanned the Atlantic Ocean. But as the demand for telegraph service soared, the capacity of each wire remained precisely the same: one message per wire per unit of time. Bell was well aware of the need for multiple telegraphy, and he had formed a notion as to how it could be achieved.

The germ of his idea had first incubated in his mind when, at the age of nineteen, he was teaching elocution and music at Weston House, a boys’ school near his native Edinburgh, Scotland. As the son and grandson of teachers of elocution, Bell had already acquired a great deal of knowledge about acoustics and the anatomy of the human vocal apparatus. One day when he was alone it occurred to him to attempt some informal experiments to determine how vowel sounds are produced. Shaping his mouth and tongue into position to pronounce a given vowel, he tapped his teeth or cheeks with his fingernail or a pencil. His trained ear easily distinguished the varying resonance pitches of his mouth cavities as they changed form in the production of different vowel sounds. He concluded that every vowel sound is the product of resonances from the changing cavities of the mouth.

Believing that his findings were original, he set them down in an enthusiastic forty-page letter to his father, Alexander Melville Hell, who was then teaching elocution in London. Bell senior passed them on to a friend and professional colleague, Alexander James Ellis, a leader in British philological circles. Regretfully Ellis informed young Bell that his work had been anticipated three years earlier by the great German physicist and physiologist Hermann von Helmholtz, who had reached similar conclusions and described them in a work that has since become a classic, On the Sensations of Tone. Helmholtz’s experiments had been vastly more elaborate than Bell’s, for he had produced vowel sounds not with the human mouth but through combinations of electrically operated tuning forks and resonators. Owing to his limited knowledge of German, Bell could not follow the intricacies of Helmholt’s exposition. But from his study of the accompanying pictures and diagrams of apparatus he concluded that the German scientist had succeeded in transmitting vowel sounds from one point to another over a wire. His assumption was completely wrong; and Ellis, who was then at work translating Hemholtz’s treatise into English, corrected him, explaining that the German had simply used electromagnets to keep his tuning forks in continuous vibration.
This episode left several important residuals in Bell’s mind. First was his discovery that tuning forks could be made to vibrate continuously by the intermittent attraction of electromagnets. Second was the concept that had grown out of his misreading of the Helmholtz text. For even though he had leapt to an inaccurate conclusion and knew he had done so, his original error began leading a life of its own in his private meditations. If one imagined that vowel sounds could somehow be transmitted over a wire, why not the entire spectrum of the human voice? And finally, he had come to realize that he lacked the knowledge of electricity required to undertake the experiments that now began to clamor in his mind for execution. He resolved to repair this deficiency, and in the following year, 1867, while engaged in teaching elocution in the city of Bath, he started experimenting in his leisure moments with telegraph apparatus, electromagnets, and tuning forks. Hc continued his investigations in London, where, from 1868 until the spring of 1870, he assisted his father with elocution classes and completed his own education at University College.

Then tragedy struck the Bell family. Three years earlier, Graham’s younger brother, Edward Charles, had died of tuberculosis. Now, in May of 1870, his older brother, Melville, who had been carrying on the original Bell elocution classes in Edinburgh since his father’s move to London, died of the same disease. And Graham himself disclosed symptoms that led doctors to warn that he too was gravely threatened. His father did not delay. Determining to get his surviving son out of London into cleaner, drier air, he abandoned his career at its most prosperous peak, sold his house, and with his wile and Graham sailed for Canada in July. A lew weeks later they moved into their new home, a modest, painted brick house perched on a height of land above the Grand River at Branlford, Ontario. [Since Bell evolved many of his fundamental concepts there, the house at Brantford is today maintained as a national monument by the government of Canada.]

Here young Bell quickly regained his health, and spent long days continuing to ponder the mysteries of electricity and sound. He also studied the language of the Mohawk Indians, which he mastered so fluently that the Mohawks, pleased, initiated him into their tribe with full ceremonial rites. Sometimes he reclined thoughtfully in a hammock strung between two birch trees on the bluff above the winding river. Sometimes he worked indoors with his tuning forks and electrical circuits, or experimented with the piano. Although he was an accomplished pianist, during this period he was less likely to play music than to strike single notes and listen intently as their harmonics rippled away in the quiet country air.

Gradually it dawned on him, ever more compellingly, that if a tuning fork could be made to vibrate by the intermittent attraction of an electromagnet, the process could be reversed— i.e., a tuning fork vibrating at a certain frequency could, when connected to a circuit with make-and-break points like those of an electric bell, impose its frequency on an electric current. Then if the intermittent current so created were transmitted along a wire to a second tuning fork, the second fork would vibrate in resonance with the transmitting fork. And thus—in accordance with the physical principle of sympathetic vibration—a given note or tone could be sent from one point to another over a telegraph wire.

Extrapolating further, Bell reasoned that if the transmitting fork were also connected to a telegrapher’s key that could open and close the circuit, the fork would then become in effect a telegraphic sender, capable of transmitting a series of Morse code signals–dots and dashes–at its own particular frequency. Now suppose further that instead of just one sending fork, you had perhaps six, each with a different pitch, or frequency, and each one paired with a receiving fork of exactly the same frequency at the other end of the line. Then if all six forks began transmitting Morse signals along the same wire at the same time, a complex electrical current carrying six different frequencies would flow through the wire to the receiving end. There each of the six receiving forks, each with its electomagnet and each tuned exclusively to the pitch of its sending partner, would vibrate in resonance with its partner—and only with its partner. The complex signal would thus be unscrambled and each of the six messages sent simultaneously over the same wire would be clearly received. This train of thought led Bell to his conception of the harmonic telegraph.

It was this conception that Bell carried with him from Brantford to Boston in the spring of 1871 when, fully recovered from his illness, he resumed his career as a teacher. He had been offered a fee of five hundred dollars by the Boston school board for a series of lectures on “Visible Speech”—a code of written symbols indicating the position and action of the vocal organs in the production of various sounds, which had been devised by his father as a valuable aid in teaching the deaf to speak. Apart from the money involved, the prospect appealed to Bell enormously for several reasons. He was anxious to return to active professional life, he enjoyed teaching, and he had always been profoundly interested in the problems of the deaf. His mother was deaf.

During the ensuing months Bell made up his mind to remain permanently in the United States, and in October, 1872, he opened a school of vocal physiology and the mechanics of speech in Boston, where he demonstrated his father’s methods before teachers of the deaf. A year later he received an appointment as professor of vocal physiology at Boston University, and transferred his students there. Through his work with the deaf, Bell met two men who would prove tremendously important to him in the years that lay just ahead. One was Gardiner Greene Hubbard, a Boston lawyer and president of Clarke Institute for Deaf-Mutes in Northampton, Massachusetts; Hubbard’s daughter Mabel had lost her hearing through an attack of scarlet fever when she was barely four years old. The other was Thomas Sanders, a prosperous leather merchant of Salem, whose five-year-old son George, born deaf, became one of Bell’s private students. Grateful to Bell for his interest in their children, both men became his close friends and within a year of their first meeting, upon learning of his electrical experiments, offered to cover his expenses in return for a share in future patent rights.

Despite his crowded daily teaching schedule, Bell continued his experiments, working far into the night in an effort to perfect the harmonic telegraph. Sometime during the winter of 1873-74 he conceived the idea of improving his device by substituting flexible strips of metal—like organ reeds or flattened clock springs—for the tuning forks. As he envisaged the new apparatus, one end of each reed would be clamped firmly to one pole of an electromagnet; the other end, extended horizontally, would be free to vibrate over the other pole. Each reed would be provided with a tuning mechanism.

Lacking the time and mechanical skill to construct the necessary parts, Bell sought help at Williams’ workshop in Court Street. At that time the electrical industry was still in its infancy, and the Williams establishment with its thirty-odd employees ranked as one of the best-equipped shops in the country. Among its employees was Thomas A. Watson, and it was he who came to assist Bell in the modification of his harmonic telegraph. From their initial encounter grew a long and rewarding professional association.

In a memoir written years afterward, Watson recalled: “I made half a dozen pairs of the harmonic instruments for Bell. He was surprised, when he tried them, to find that they didn’t work as well as he expected.” The failures, however, were blessings in disguise. For, as Watson pointed out, “Had his harmonic telegraph been a well-behaved apparatus that always did what its parent wanted it to do, the speaking telephone might never have emerged from a certain marvellous conception that had even then been surging back of Bell’s high forehead for two or three years.”

That marvellous conception had slowly flowered through a synthesis of ideas and observations made in the course of his work on the harmonic telegraph. After he had given up on the tuning forks and had started to think in terms of organ reeds, he began to contemplate larger numbers of transmitting units. He knew from his musical experience that if he put his head inside a piano and sang or spoke, a number of strings would respond. Hence if he constructed a “harp transmitter” with enough strings or reeds to pick up every frequency of the human voice, their combined vibrations could be converted into a complex electric current that would vary in intensity with the varying sounds of the voice. And a receiver harp at the other end of the circuit would reproduce those sounds. Although Bell suspected that his theoretical harp transmitter was too big, too complicated, and probably too expensive to be practical, he nevertheless felt that the underlying principles were sound, and the conception persisted in his mind.

Meanwhile, his work with the deaf had taken him one day to the physics laboratory at the Massachusetts Institute of Technology to inspect a remarkable new instrument called the phonautograph. This contrivance was a kind of speaking trumpet, closed at the far end by a stretched membrane. Attached to the membrane was a stylus. When words were spoken into the mouthpiece the membrane vibrated, causing the stylus to trace an oscillating wave pattern on a piece of smoked glass. Bell thought that the instrument might be useful in teaching articulation to the deaf by revealing to them visually the relationship between the sounds they articulated, or tried to articulate, and the patterns traced by the stylus on the smoked glass.

Unfortunately the phonautograph did not work satisfactorily for Bell’s purposes. He was struck, however, by a similarity between its mechanism and that of the human ear, and it occurred to him that the phonautograph might be improved were it modelled more closely upon the structure of the ear. Seeking more accurate anatomical information, he consulted a famous Boston ear specialist, Dr. Clarence J. Blake. Somewhat to Bell’s surprise, Blake suggested that instead of constructing a phonautograph around a model of the ear, he should use an actual human ear, excised from some donor in the morgue. What was more, the Doctor would provide one. And he did, properly preserved and prepared for scientific study. The experiment proved highly successful. Bell constructed a new phonautograph, using the ear as a component, and found that its tracings of sound patterns on the smoked glass were vastly more accurate than those of the instrument at M.I.T. But what stirred Bell more deeply than this hope of a new device for teaching the deaf was the opening of a new avenue of thought provided by his glimpse into the secret corridors of the inner ear.

Bell carried his apparatus home with him to Brantford in July, 1874, and continued his experiments with it during his summer vacation. He continued to marvel over the mechanisms of the ear, and especially the ability of the tiny diaphragm—the ear drum—to move the relatively heavy bones of the ear. Then suddenly, on July 26, 1874, one of those amazing cross-circuits of thought that happen without premeditation produced a blinding scintillation in his mind. For several hours he had been brooding over the problems inherent in his harp transmitter, wondering if he could not find a less cumbersome device than one involving a whole choir of strings or reeds—and some simpler way to pick up the sounds of the human voice and generate a current that would vary in intensity as the air varied in density during the production of those sounds.

Years later Bell described the exact moment at which he suddenly perceived the solution he had sought: “I do not think that the membrane of the ear could have been half an inch in diameter and it appeared to be as thin as tissue paper. . . . It occurred to me that if such a thin and delicate membrane could move bones that were, relatively to it, very massive indeed, why should not a larger and stouter membrane be able to move a piece of steel in the manner I desired?”

Bell knew now he could discard all the capricious and multitudinous reeds in his harp transmitter. A single diaphragm could take their place. And a single magnetized reed, attached to the center of the diaphragm and vibrating with the sound of the human voice, could generate a current that would vary in intensity precisely as the air varied in density during the production of that sound.

“At once the conception of a membrane speaking telephone became complete in my mind,” Bell related, “for I saw that a similar instrument to that used as a transmitter could also be employed as a receiver.”

The vision was there, clear and correct. But many problems of many kinds remained. A technical question that still loomed large concerned the matter of electrical induction. Both Michael Faraday in England and Joseph Henry in America had shown almost concurrently, a few decades earlier, that when a magnetized object is moved toward an electromagnet, a current is induced (generated) in the electromagnet’s coil; and when it is moved away from the electromagnet a current of the opposite kind is induced. (See “Professor Henry and His Philosophical Toys” in the December, 1963, AMERICAN HERITAGE.) It was this principle that Bell had invoked. But he wondered now if the current induced by his magnetized reed, vibrating over an electromagnet’s pole, would be strong enough to activate the receiver.

A problem of quite another variety now appeared. His financial backers in Boston, Hubbard and Sanders, were sponsoring his experiments in multiple telegraphy, and not his visionary notion of transmitting human speech by wire. Both men were convinced that success for all of them hinged on Bell’s ability to perfect and patent the harmonic telegraph with all possible speed. Western Union was stringing lines across the entire continent; it was overwhelmed with more messages than it could transmit; and, most alarming of all, other inventors were aware of the principle of the harmonic telegraph and were competing to win the race. Yet when Bell returned to Boston at summer’s end his thoughts were still dominated by the revelations of July. Moreover, he and Watson appeared to be making little progress toward their objective of evolving a workable harmonic telegraph. It continued to balk their best efforts. Night after night they labored vainly to persuade transmitters and receivers to vibrate in monogamistic resonance with their respective mates —and with no others. It seemed that however carefully they adjusted the tuning mechanisms, the pulses that cascaded along the wire overlapped each other in turbulent disarray.

One evening, as they sat down on a bench for a brief recess, Bell decided to take Watson into his confidence and inform him of his summer speculations. As Watson recalled the conversation in later years,
Bell said to me, “Watson, I want to tell you of another idea I have which I think will surprise you!” I listened, I suspect, somewhat languidly, for I must have been working that day about sixteen hours, with only a short nutritive interval . . . but when he went on to say that he had an idea by which he believed it would be possible to talk by telegraph, my nervous system got such a shock that the tired feeling vanished. I have never forgotten his exact words; they have run in my mind ever since like a mathematical formula. If,” he said, I could make a current of electricity vary in intensity, precisely as the air varies in density during the production of a sound, I should be able to transmit speech telegraphically.

Bell then took a piece of paper and made a sketch of his telephone transmitter as he envisaged it. They discussed it for a while and then went back to their labors on the harmonic telegraph. As Watson remembered later, they agreed that “the chances of its working were too uncertain to impress his financial backers . . . who were insisting that the wisest thing for Bell to do was to perfect the harmonic telegraph; then he would have money and leisure enough to build air castles like the telephone.”

Nevertheless Bell did muster up his courage a few days later. He approached Hubbard and Sanders and asked if they would care to sponsor his new conception. The answer was no. They saw no immediate need for such an instrument, while on the other hand there was a great demand for the harmonic telegraph and every urgent reason for bringing it to practical completion. Indeed, they exhorted Bell to hurry to Washington and register his specifications with the Patent Office.

Bell’s trip to Washington in February, 1875, proved a fateful one, for while he was in the capital he called upon Joseph Henry, dean of American physicists, inventor of the electric motor, and secretary of the Smithsonian Institution. In later years Bell spoke of this interview as a turning point in his career. For although the great physicist, then nearly eighty years old, listened with courteous interest while Bell described his harmonic telegraph, his interest turned to excitement when the young inventor went on to discuss his hopes of transmitting human speech over a wire. He told Bell that he had “the germ of a great invention” and urged him to forge ahead with his experiments. When Bell expressed fear that he lacked the electrical knowledge necessary to overcome the difficulties, Henry said laconically, “Get it!”

Four months elapsed between Bell’s conversation with Henry and the moment of enlightenment that forever afterward Bell and Watson would remember as the crucial episode of their collaboration. Those final months were not easy ones. Watson wrote later:

But this spring of 1875 was the dark hour just before the dawn. . . . The date when the conception of the undulatory or speech-transmitting current took its perfect form in Bell’s mind [was] the greatest day in the history of the telephone, but certainly June 2, 1875, must always rank next; for on that day the mocking fiend inhabiting that demonic telegraph apparatus . . . opened the curtain that hides from man great Nature’s secrets and gave us a glimpse into that treasury of things not yet discovered. . . . [Watson’s literary style is hardly what one would expect from a man who left school at the age of thirteen. However, when he was forty, he entered M.I.T. and took courses in literature, geology, and biology—subjects which dominated his interest in later years. He left the American Bell Telephone Company in 1881 and spent a year in Europe. On his return he went into shipbuilding and founded the Fore River Ship and Engine Company in East Braintree, Massachusetts, which had a large share in building the U.S. fleet that fought the Spanish-American War. In 1904, aged fifty, he retired from business and spent the remaining years of his life in travel. He died in 1934.]

In the course of their experiments on the harmonic telegraph, Bell had found the source of their difficulties. The trouble lay in their inability to tune transmitters and receivers into precise and perfect congruence. Since Bell had a musical ear (and Watson did not), it was he who undertook the finicky and seemingly endless job of adjusting the tuning screws. His method was to hold the vibrating spring, or reed, of a receiver close to his ear while the corresponding transmitter in the other room was sending its intermittent current through the electromagnet. He would then manipulate the tuning screw until the vibratory whine emitted by the spring of the receiver appeared to coincide with the whine coming—through the air—from the transmitter.

On the afternoon of June 2, 1875 [Watson continued], we were hard at work on the same old job, testing some modification of the instruments. Things were badly out of tune that afternoon in that hot garret, not only the instruments, but, I fancy, my enthusiasm and my temper, though Bell was as energetic as ever. I had charge of the transmitters as usual, setting them squealing one after the other, while Bell was retuning the receiver springs one by one, pressing them against his ear as I have described.

One of the transmitter springs I was attending to stopped vibrating and I plucked it to start it again. It didn’t start and I kept on plucking it, when suddenly I heard a shout from Bell in the next room, and then out he came with a rush, demanding, “What did you do then? Don’t change anything. Let me see!”

Bell, at the other end of the line, had heard in his receiver a startling, unbelievable sound, a sound quite different from the familiar whine of the vibrating transmitter. Instead he had heard the distinctive metallic twang-g! of a plucked spring, a sound with tones and overtones, a sound that made his heart stand still.

Watson showed him what had happened. The contact screw had been set down so far that it had made permanent contact with the spring. Hence when Watson plucked the spring the circuit remained unbroken. And instead of producing an intermittent current, the spring had acted as a diaphragm and sent an induced, undulating current over the line. In Watson’s words,

That strip of magnetized steel by its vibration over the pole of its magnet was generating that marvellous conception of Bell’s—a current of electricity that varied in intensity precisely as the air was varying in density within hearing distance of that spring. That undulatory current had passed through the connecting wire to the distant receiver which, fortunately, was a mechanism that could transform that current back into an extremely faint echo of the sound of the vibrating spring that had generated it.

What was still more fortunate, the right man had that mechanism at his ear during that fleeting moment, and instantly recognized the transcendent importance of that faint sound thus electrically transmitted. The shout I heard and his excited rush into my room were the result of that recognition.

The speaking telephone was born at that moment. Bell knew perfectly well that the mechanism that could transmit all the complex vibrations of one sound could do the same for any sound, even that of speech. … All the experimenting that followed that discovery, up to the time the telephone was put into practical use, was largely a matter of working out the details.

For several hours after the unforgettable twang, Bell and Watson repeated the experiment, changing places, changing the circuits, testing each pair of transmitters and receivers, and cross-checking each other’s observations. On through the afternoon and into the night, “there was little done but plucking reeds and observing the effect”—this time the words are Bell’s. But faintly as the signals came through, they were there and they were true. And Bell now knew that his invention could be made to work, for his major and most persistent fear had been resolved. As he expressed it some thirty years afterward, “These experiments at once removed the doubt that had been in my mind since the summer of 1874, that magneto-electric currents generated by the vibration of an armature in front of an electromagnet would be too feeble to produce audible effects that could be practically utilized.”

Before they parted company for the night, Bell gave Watson instructions for making the first speaking telephone. The specifications were simply those of the membrane telephone which he had envisaged at his home in Brantford the summer before. Watson promised to have it ready the next day. Bell walked the streets for some time and when he returned to his lodgings found he could not sleep. Though elated, he felt guilty at having invented the telephone when his sponsors expected him to be hard at work on the harmonic telegraph. Before he went to bed he wrote a letter to Hubbard.

“Dear Mr. Hubbard,” he began. “I have accidentally made a discovery of the very greatest importance. . . . ”

On the next day, June 3, 1875, Watson constructed the first Bell telephone. As a mouthpiece, he arranged a small hollow cylinder, closed at one end by a tautly stretched parchment membrane. To the center of the membrane he attached the free end of a transmitter spring. It was a beautifully simple mechanism. When a person spoke into the mouthpiece, sound waves from his voice caused the membrane to vibrate. The membrane then caused the attached transmitter spring to vibrate. And the transmitter spring, vibrating over one pole of its electromagnet, induced an undulatory current that varied in intensity as the air varied in density during the production of vocal sounds.

That evening Bell and Watson met at the shop, after the workmen had gone home, for the initial tests. Surmising that the signal would be faint at best, and that both he and Bell would doubtless be shouting at the top of their lungs, Watson had taken the precaution of running the wire—the world’s first telephone line–from their fifth-floor garret down to the third floor, to lessen the chance of hearing each other directly through the air. On the first test the new telephone was placed on Watson’s workbench, while Bell stationed himself at a receiver in the garret. Watson shouted; but Bell, straining his ears, could hear nothing. They then exchanged places, with Bell at the transmitter below and Watson upstairs. This time the results were more encouraging.

“I could unmistakably hear the tones of his voice,” Watson recalled later, “and almost catch a word now and then. I rushed downstairs and told him what I had heard. … It was enough to show him that he was on the right track, and before he left that night he gave me directions for several improvements in the telephones I was to have ready for the next trial.”

Watson attributed the one-way transmission that night not to any defect in the system but to Bell’s lifelong training in elocution: “The reason why I heard Bell in that first trial of the telephone and he did not hear me, was the vast superiority of his strong vibratory tones over any sound my undeveloped voice was then able to utter.” He then added dryly, “My sense of hearing, however, has always been unusually acute, and that might have helped to determine this result.”

In any event, the business of what Watson had called “working out the details” continued to be a somewhat sticky one. The experiments went on all summer as Bell and Watson juggled components in an attempt to improve reception. They could hear each other’s voices, but only rarely could they distinguish fragments of sentences, isolated phrases, or scattered words. Day after fruitless day they found themselves at a loss as to what to try next. Bell’s problems, moreover, were aggravated by other factors. He was deeply involved in drafting specifications and claims for patent rights, foreign and domestic, on both the harmonic telegraph and the telephone[Bell's basic U.S. Patent No. 174,465, covering the telephone–"The method of, and apparatus for, transmitting vocal or other sounds telegraphically, as herein described, by causing electrical undulations similar in form to the vibrations of the air accompanying the said vocal or other sounds, substantially as set forth"–was granted on March 7, 1876.]; hence much of his time was consumed in paper work. Then too, his health took a turn for the worse during the hot summer months. And finally, he was beset by financial difficulties. In his zeal to perfect the telephone he had abandoned all his teaching engagements, and now his funds were running low. While his sponsors had agreed to cover his laboratory expenses, no provision had been made for personal expenses. Bell was reluctant to request further assistance, for although both men now saw the potential of the telephone, Sanders had already invested large sums in Bell’s work without return, and Bell’s relationship with Hubbard was even more sensitive. For he hoped, when he became more solvent, to marry Hubbard’s daughter, Mabel.

Seeing no other solution to his predicament, Bell returned briefly to his work with the deaf, lecturing to student teachers and building up a new clientele of private pupils. Toward the end of 1875 his circumstances improved. He was able to move his apparatus from the Williams shop, where it had been eyed by increasing numbers of inquisitive strangers, to private quarters of his own in 5 Exeter Place, Boston. There, through the winter and early spring, Bell continued his experiments and evolved a new and modified transmitter, abetted by a variable battery current. On the night of March 10, 1876, just nine months after Bell’s harmonic telegraph receiver gave out its promising twang, his telephone pronounced its first complete and intelligible sentence. Watson, who had continued to assist Bell faithfully, constructing his apparatus and working with him night after night no less assiduously than at the workshop in Court Street, was on the receiving end this time, and he recorded the event:

It made such an impression upon me that I wrote that first sentence in a book I have always preserved. The occasion had not been arranged and rehearsed as I suspect the sending of the first message over the Morse telegraph had been years before, for instead of that noble first telegraphic message—“What hath God wrought?”—the first message of the telephone was: “Mr. Watson, come here, I want you.” Perhaps if Mr. Bell had realized that he was about to make a bit of history, he would have been prepared with a more sounding and interesting sentence.

Thereafter events moved swiftly. In June, 1876, Bell exhibited his apparatus at the Centennial Exposition in Philadelphia, where he won prizes for both the telephone and his harmonic telegraph. Among the judges were Joseph Henry; the Emperor Dom Pedro of Brazil, who exclaimed, “My God, it talks”; and Sir William Thomson (Baron Kelvin), who later called the telephone “the most wonderful thing [he had seen] in America.” There followed a series of demonstrations in both the United States and Canada, with lectures by Bell and gradually lengthening lines of communication. The demonstration circuits began with two miles of wire between Bell’s home in Brantford and the neighboring town of Mount Pleasant; by the spring of 1877 a line had been set up from New Brunswick, New Jersey, to New York City, a distance of more than thirty miles. (The wires were leased, for these occasions, from Western Union.) The reactions of audiences ranged from incredulity, through enthusiasm, to skepticism. Some saw in the telephone only an ingenious novelty. Shortly after the Philadelphia Centennial Exposition, the New York Tribune commented editorially in this vein:

Of what use is such an invention? Well, there may be occasions of state when it is necessary for officials who are far apart to talk with each other, without the interferences of an operator. Or some lover may wish to pop the question directly into the ear of a lady and hear for himself her reply, though miles away; it is not for us to guess how courtships will be conducted in the twentieth century. It is said that the human voice has been conveyed by this contrivance over a circuit of sixty miles. Music can be readily transmitted. Think of serenading by telegraph!

During this period, when Bell was beginning to win great acclaim but still languished in financial distress, Gardiner Hubbard decided to execute a coup. He approached the Western Union Company and offered to sell them all the Bell patents for a lump sum of $100,000. He added that Bell would be willing to put on a private demonstration for officers of the company. The president of Western Union spurned the offer of a demonstration and refused the patents, explaining that they “could not make use of an electrical toy.” Commenting wryly on this rude rejection, Watson, who was now devoting his full time to the telephone in return for an interest in the Bell patents, observed: “It was an especially hard blow to me, for . . .  I had had visions of a sumptuous office in the Western Union Building in New York, which I was expecting to occupy as Superintendent of the Telephone Department of the great telegraph company. However, we recovered even from that. … Two years later the Western Union would gladly have bought those patents for $25,000,000.”

Undismayed, Bell and Watson continued with their experiments. They made telephones with every modification and combination of components that they could imagine. They tested all kinds of materials, all kinds of diaphragms, and all kinds of magnets. In the end, after hundreds of experiments, they dispensed with the membrane diaphragm in favor of a thin iron one. They found too that telephones with permanent magnets working without any battery gave better results at a distance than telephones containing electromagnets operated by a battery current. Thus two outstanding characteristics of the later telephone—permanent magnets and metallic diaphragms—had already been added in that early day.

In July, 1877, Bell married Mabel Hubbard and shortly thereafter sailed with his bride to England to introduce the telephone there. He delivered many lectures and gave many demonstrations, most notably one for Queen Victoria at Osborne on the Isle of Wight. But Bell’s trip was most memorable for an amazingly prophetic document which he composed on the night of March 15, 1878, at his rented house in Kensington. It was in the form of a prospectus designed to awaken the interest of English investors in the Electric Telephone Company. In view of the fact that the telephone was still in its infancy, the vision embodied in these paragraphs discloses a depth and scope of imagination that matched Bell’s inventive genius.

At the present time we have a perfect network of gas-pipes and water-pipes throughout our larger cities. We have main pipes laid under the streets communicating by side pipes with the various dwellings, enabling the members to draw their supplies of gas and water from a common source.

In a similar manner, it is conceivable that cables of Telephone wires could be laid underground or suspended overhead communicating by branch wires with private dwellings, counting houses, ships, manufactories, etc., etc., uniting them through the main cable with a central office where the wires could be connected as desired, establishing direct communication between any two places in the city. Such a plan as this, though impracticable at the present moment, will, I firmly believe, be the outcome of the introduction of the Telephone to the public. Not only so, but I believe that in the future wires will unite the head offices of the Telephone Company in different cities and a man in one part of the country may communicate by word of mouth with another in a distant place.

Thus in the spring of 1878 Bell foresaw clearly how his invention would alter the whole tapestry of human existence. He knew exactly what he had brought into being, and he entertained not the slightest doubt that before very long every home and place of business would possess a telephone, and that through its sorcery the human voice, transcending all barriers of time and distance, would be heard around the world. It is noteworthy too that Bell’s prospectus of 1878 introduced some terminology that has remained a basic and permanent part of the lexicon of the telephone. From his concept of a “central office” came the salutation “Hello, Central,” which, until the advent of the dial system, was uttered by more people every hour of every day than any other phrase in the English tongue.

By the time Bell and his wife returned to the United States at the end of 1878 the telephone was well on its way to becoming a big business. Never before had a revolutionary invention entered into commercial use so swiftly. The first central switchboard had been established in Boston (with boys as operators, until some inspired but forgotten genius discovered that girls were more polite). The first private line had been strung between Williams’ electrical workshop in Court Street and his home in Somerville, Massachusetts. Thereafter, with amazing rapidity wires wove steel traceries across the New England landscape and telephone poles sprouted like autumn weeds. Businessmen, lawyers, doctors, quickly discovered that, quite apart from efficiency and convenience, there was an element of status in owning a telephone. The first directory appeared in New Haven, with a list of fifty subscribers—among them the police department and the post office. And in Boston, Bell’s canny business managers, Hubbard and Sanders, supervised the manufacture and rental of telephone instruments, and girded up their loins for the first of an interminable series of legal battles in which the Bell associates would have to defend their basic patents against an army of predators. For it was becoming clear to electrical and telegraph companies that Bell Patent No. 174,465 was a valuable one. As events subsequently showed, it turned out to be the most valuable patent ever issued in the history of the U.S. Patent Office. By December of 1879, stock in the New England Telephone Company was selling at $995 a share.

Meanwhile Watson—chief technician in Bell’s absence—found himself confronted with the problem of devising a method of summoning people to the telephone. For some reason Bell had not thought of a bell.

It began to dawn on us [Watson recalled] that people engaged in getting their living in the ordinary walks of life couldn’t be expected to keep the telephone at their ear all the time waiting for a call, especially as it weighed ten pounds then and was as big as a small packing case, so it devolved on me to get up some sort of a call signal. Williams, on his line, used to call by thumping the diaphragm through the mouthpiece with the butt of a lead pencil. If there was someone close to the telephone at the other end, and it was very still, this worked pretty well, but it seriously damaged the vitals of the machine and therefore I decided it wasn’t really practical for the general public; besides, we might have to supply a pencil with every telephone . . . 

Then I rigged a little hammer inside the box with a button on the outside. When the button was thumped the hammer would hit the side of the diaphragm where it could not be damaged, the usual electrical transformation took place, and a much more modest but still unmistakable thump would issue from the telephone at the other end. . . .

But the exacting public wanted something better, and I devised the Watson “Buzzer”—the only practical use we ever made of the harmonic telegraph relics. Many of these were sent out. It was a vast improvement on the Watson “Thumper,” but it still didn’t take the popular fancy. It made a sound quite like the horseradish-grater automobile signal . . . and aroused just the same feeling of resentment. It brought me only a fleeting fame for I soon superseded it by a magneto-electric call bell that solved the problem, and was destined to make a long-suffering public turn cranks for the next fifteen years or so, as it never had before or ever will hereafter.

Watson solved another problem at this time which proved important in the future development of the telephone system. In his first version of the magneto call bell he had incorporated a manual switch that had to be thrown one way by hand when the telephone was being used, and then thrown back by hand when the call was terminated in order to put the bell back in circuit again.

But, Watson soon discovered, “the average man or woman wouldn’t do this more than half the time, and I was obliged to try a series of devices, which culminated in that remarkable achievement of the human brain—the automatic switch—that only demanded of the public that it should hang up the telephone after it got through talking. This the public learned to do quite well after a few years of practice.”

For the next three years after Bell’s return from England, both he and Watson were compelled to spend most of their time either testifying in court or preparing to testify. Again and again Watson found himself building reproductions of the original telephone instrument in order to prove to judges and juries that it actually had worked right from the start. The litigation went on for decades, and in time virtually every big electrical and telegraph company in the United States mobilized its technical and legal resources in all-out battles to break the bulwarks of Patent No. 174,465. When Western Union tardily recognized the potential of Bell’s invention, just two years after they had haughtily spurned Hubbard’s offer to sell it to them for $100,000, they engaged Thomas Edison and Elisha Gray to evolve instruments that would work as well as the Bell telephone and yet evade the restrictions of the basic patent. Edison did, indeed, evolve a carbonbutton transmitter that proved superior to Bell’s magneto transmitter, as Watson rather ruefully admitted afterward.

“Our transmitter was doing much to develop the American voice and lungs,” he observed, “making them powerful but not melodious. This was the telephone epoch when, they used to say, all the farmers waiting in a country grocery would rush out and hold their horses when they saw anyone preparing to use the telephone.”

The basic principles involved in Patent No. 174,465 were, however, unique, inimitable, and not subject to disguise or variation. The patent withstood all assaults, and one by one the various adversaries were struck down by the courts—and on several occasions by the U.S. Supreme Court.

Both Bell and Watson separated themselves from the telephone company in the same year, 1881, and turned their restless minds to other interests. By now both young men were financially secure for life; they were, indeed, rich, and they were bored by such matters as law suits and corporate expansion. “Bell was a pure scientist,” Watson explained. “Making money out of his idea never seemed to concern him particularly.” When the Bell Telephone Company of Canada was incorporated, Bell gave three quarters of his interest to his father and generously dispensed smaller fractions to many others who had helped him. To his wife he gave his entire holdings in the American company as a wedding gift, along with complete control of his financial affairs. Once, while at home in Brantford on vacation, he was asked to return to the States to testify in another patent suit. Throwing up his hands in exasperation, he declared that he would rather surrender all interest in the telephone and devote the rest of his life to teaching the deaf than participate in one more piece of litigation.

As for Watson, he resigned his position as General Inspector of the New England Telephone Company, partly because the incessant pressures of the embattled and swiftly expanding firm had given him chronic insomnia, and partly because “the telephone business had become, I thought, merely a matter of routine, with nothing more to do except pay dividends and fight infringers.” In this latter assumption, events were to prove him incorrect. For the telephone system, from the day it was born, was a living organism that immediately began a process of expansion and technical development that has accelerated with each passing year. The process involved vastly more than the bare necessities of festooning additional miles of wires or manufacturing thousands of new phones. Other original minds, other gifted technicians, took up where Bell and Watson left off. By 1900, less than a quarter century after Bell filed his original patent, more than three thousand patents had been filed in Washington by the second generation of Bell inventors.

Bell’s creation of the telephone overshadowed later achievements that by themselves would have insured a degree of immortality to a lesser man. He made important advances toward the development of the photoelectric cell, the phonograph, the iron lung, and the desalination of ocean water. Working with the aviation pioneer S. P. Langley, he contributed valuably to aeronautical theory, in which he was intensely interested; on a practical level, he was the co-inventor of the aileron as a device to control the lateral balance of an airplane.

Yet through all his years of international fame and glory, until his death in 1922, Bell never lost his interest in the problems of the deaf. With $300,000 of his own money he founded the American Association to Promote the Teaching of Speech to the Deaf, and he developed a lifetime friendship with Helen Keller, whom he first knew in 1886 as a six-year-old still almost completely mute. He was always tenderly considerate of his deaf wife, and repeatedly, from the time of his first triumphs in Boston, he declared that he would rather be remembered by posterity as one who had helped the deaf than as the inventor of the telephone.