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, nobody 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 twang, 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 assisting 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, Massachusetts, 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 passed 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 passage 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.
