Fig. 6.
Mr. Horkheimer, a former pupil of Reis, informs me that a much larger model of the ear was also constructed by Reis. No trace of this is, however, known.
Second Form.—Tin Tube.
The second form, a tube constructed by Reis himself, of tin, is still to be seen in the Physical cabinet of Garnier’s Institute, at Friedrichsdorf, and is shown in [Fig. 7]. It consists of an auditory tube a, with an embouchure representing the pinna or flap of the ear. This second apparatus shows also a great similarity with the arrangement of the ear, having the pinna or ear-flap, the auditory passage, and the drum-skin (a, b, c). Upon the bladder c there still remains some sealing-wax, by means of which a little strip of platinum, for the all-essential loose-contact that controlled the current, had formerly been cemented to the apparatus.
Fig. 7.
Third Form.—The Collar-box.
