More comprehensive, so far as the scientific descriptions enable us to judge, is Bell's _telephone_, for the transmission of talk and sing-song as well as of instrumental sounds. If present indications should be really justified by future results, the imagination can scarcely picture the number of practical applications that may ensue. The inventor, Mr Graham Bell, went to America in 1871. He is the son of Mr Alexander Melville Bell, whose system of 'Visible Speech' has attracted a good deal of notice on both sides of the Atlantic. Both father and son have been practically engaged in perfecting a system for teaching the dumb to speak; and Mr Graham Bell set himself the task of accomplishing something which would justify him in saying: 'If I can make a deaf-mute talk, so can I make iron talk.'[A] Mr Bell, when at Salem in Massachusetts, began to turn his attention to this subject, the telegraphy of sound, or _telephony_, in 1872; but three years elapsed before the matter assumed such a form as to enable him to send a little musical message through a two-mile wire. Securing his invention by a patent, he gave his first public exhibition of the system in the autumn of 1876. The talk or speaking of an operator at Cambridge, Massachusetts, was heard at Boston, in the ordinary conversational tones. It does not appear that the actual quality or _timbre_ of the voice was distinguishable, but only a voice, speaking certain words. Early in the present year, however, further improvements were made in the apparatus which enabled it to shew even this kind of delicacy; that is, it transmitted not merely the words in sound, but also the tones and inflections of different voices. Singing being, in regard to acoustics, only one variety of speaking, it follows almost as a matter of course that if the apparatus can talk it can also sing. Accordingly, a lady sang _The Last Rose of Summer_, and was distinctly heard at the distant station; the sounds 'had about the same effect as if the listeners were at the rear of a concert-hall, say a hundred feet from the singer.' The sounds of laughter and applause were similarly transmitted, with the proper rhythm and key or musical pitch. In instrumental music a violin could be distinguished from a violoncello; a test more delicate than would be supposed by many persons.