Reis’s first instrument was (see p. 16) nothing else than a model of the mechanism of the human ear. Why did he choose this fundamental type which runs through all his instruments from first to last? The reason is given in his own first memoir (p. 51), “_How could a single instrument reproduce at once the total actions of all the organs operated in human speech? This was ever the cardinal question._” Reis constructed his instrument therefore with intent to reproduce human speech. For this reason he borrowed from the ear the suggestion of a _tympanum_. Of the operation of the tympanum he had the most exact and perfect conception. He says (p. 54), “_Every tone, and every combination of tones_”--and this includes articulate tones, of course, and is just as true of them as of any other kind--“_evokes in our ear, if it enters it, vibrations of the drum-skin, the motions of which may be represented by a curve_.” And further: “_As soon, therefore, as it shall become possible, at any place and in any prescribed manner, to set up vibrations whose curves are like those of any given tone, or combination of tones, we shall then receive the same impression as that tone or combination of tones would have produced upon us._” Again, it is clear that his study of acoustics led him to employ the tympanum, because of its special value in responding to all the complex vibrations of human speech. It is no less significant that when a decade later Varley, Gray, and Bell, set themselves to invent tone-telephones for the purpose of multiple telegraphy, they abandoned tympanums as being _unsuitable_ for tone-telephones, and in lieu thereof employed vibrating tongues like those of tuning-forks. Reis’s use of the tympanum had a very definite meaning then; it meant nothing less than this: I intend my instrument to transmit any sound that a human ear can hear. That it was explicitly within his intention to transmit speech is confirmed by another passage of his first memoir (p. 58), wherein he remarks with a shade of disappointment that though “the consonants are for the most part tolerably distinctly reproduced, the vowels are not yet to an equal degree.” To his own pupils and co-workers he communicated his ideas. One of the former, Mr. E. Horkheimer, now of Manchester, expressly says (see p. 117) that Reis’s intention was to transmit speech, and that the transmission of music was an afterthought adopted for the convenience of public exhibition, just as was the case with the public exhibitions of Bell’s Telephone fifteen years later.