The engraving presented below (Fig. 12) has been engraved with the utmost fidelity by Mr. J. D. Cooper, from a photograph lent to the author by Ernest Horkheimer, Esq., of Manchester, a former pupil of Reis. The original photograph was taken in 1862, having been sent by Reis in June of that year to Mr. Horkheimer, who had left for England. The photograph was taken by Reis himself with his own camera, the exposure being managed by a slight movement of the foot, actuating a pneumatic contrivance of Reis’s own invention, which was originally designed to turn over the pages of a music book at the piano. Reis is here represented as holding in his hand the telephone with which he had a few days preceding (May 11, 1862) achieved such success at his lecture before the Freies Deutsches Hochstift (Free German Institute) in Frankfort (see p. 66). This instrument was constructed by Reis, young Horkheimer assisting him in the construction. Mr. Horkheimer has very obligingly indicated from memory the form of the instrument--but dimly seen in the photograph--in a sketch from which Fig. 13 has been prepared. Mr. Horkheimer adds that the cone was a wooden one; and that the square patch behind at the back was, he thinks, a box to contain an electro-magnet. [Illustration: Fig. 13.] _Eighth Form._--LEVER FORM. [Illustration: Fig. 14.] The Transmitter described with so much minuteness by Inspector von Legat in his Report on Reis’s Telephone in 1862 (see p. 70), differs from the earliest and latest forms, so much so that some have doubted whether this form was really invented by Reis. It is not described anywhere else than in Legat’s Report (in the “Zeitschrift” of the Austro-German Telegraph Union, reprinted also in Dingler’s Journal), except in Kuhn’s Handbook, where, however, the description is taken from Legat. Nevertheless a comparison of this instrument (Fig. 14) with the original model of the ear, from which Reis started, will show that it embodies no new point. There is, first, a conical tube to receive the sound, closed at its end with a tympanum of membrane. There is next a curved lever, _c d_, the lower end of which rests against the centre of the membrane. Thirdly, there is a vertical spring, _g_, which makes contact lightly against the upper end of the curved lever. Lastly, there is an adjusting screw. It may be further pointed out that in each case the current enters (or leaves, as the case may be) the lever at its middle point. This form of transmitter is so closely allied indeed to the primitive “ear” as to be alike in every feature save the external form of the sound-gathering funnel. The only reasonable doubt is not whether it be, as Legat asserts, Reis’s transmitter, but whether it ought not in chronological order to rank second. Legat’s paper was not published, however, till 1862, whilst the fourth form was described by Reis in 1861. No trace of any instrument corresponding in form to Fig.