第56章

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 mass 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, retarded 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 document; 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 Institution, 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 passes 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.'