October 5, IS&J.) 



SCIENCE. 



473 



and impartial record of liistoric verities. His 

 book is throughout a labored special pleading, 

 with the attempt to prove that Reis's invention 

 not only anticipated, but actually embodied, the 

 essential features of the present telephonic ap- 

 paratus. Space will not permit the considera- 

 tion of all the points which miglit be criticised, 

 nor is it necessary. A few of the most impor- 

 tant are sufficient to illustrate the spirit which 

 pervades the work, and to show how the facts 

 of history- are perverted in the endeavor to 

 maintain a false and illogical position. 



It has been generally accepted as true, that 

 Reis designed his transmitter to act as a con- 

 tact-breaker, which should open and close the 

 circuit once for each vibration produced bj- the 

 sound to be transmitted. The support for this 

 view is found not only in the repeated state- 

 ments of Keis himself, but also in the con- 

 struction of the apparatus. Reis saj-s, in his 

 own description of his transmitter (p. 56), 

 " each sound-wave effects an opening and a 

 closing of the current ; " and again, in his let- 

 ter to Mr. Ladd (p. 84), " If a person sing at 

 the station A, in the tube (x) the vibrations 

 of air will pass into the bos and move the mem- 

 brane above ; thereby the platina foot (c) of the 

 movable angle will be lifted up and will thus 

 open the stream at ever^' condensation of air in 

 the box. The stream will be re-established at 

 ever^' rarefaction. For this manner the steel 

 axis at station B will be magnetic once for 

 everj- full vibration." 



With these and other most distinct state- 

 ments of Reis, as to the intention and action 

 of his apparatus, before him. Professor Thomp- 

 son, nevertheless, asserts that it was never 

 designed to break the circuit. Thus, on p. 14 

 he says, " Theoreticallj', the last was no more 

 perfect than the first, and they all embody the 

 same fundamental idea : they only differ in the 

 mechanical means of carr3ing out to a greater 

 or less degree of perfection tlie one common 

 principle of imitating the mechariism of the 

 human ear, and applying that mechanism to 

 affect or control a current of electricit}' by vary- 

 ing the degree of contact at a loose joint in the 

 circuit." And again (p. Ki'J), "Now this 

 operation of varying the degree of pressure in 

 order to vary the resistance of the intcrruptor 

 or contact-regulator, was distiuctl}' contem- 

 plated by Reis." Further, the author main- 

 tains that the combination of an adjusting-screw 

 with a spring shows that Reis intended the 

 platinum contact-jiiece to have a following 

 motion, so as to make a contact with varying 

 pressure. He says on p. 1;13, "By eraplo}'- 

 ing these following-springs, he introduced, in 



fact the element of elasticity into his intcr- 

 ruptor ; and clearly he introduced it for the very 

 purpose of avoiding abrupt breaking of the 

 contact." If we examine the illustrations of 

 the different forms 

 of the transmitting 

 apparatus, we shall 

 see that this device 

 was employed for a 

 vcr}- different pur- 

 pose. In the ear- 

 liest form, repre- 

 sented in fig. 1, the 

 screw presses the 

 spring aivay from 

 the membrane, and, 

 when the latter re- 

 cedes in its vibra- 

 tion, the spring 

 carrying the plati- 

 num point is pre- 

 vented by the screw 

 from following it, 

 — an arrangement 

 that tends to pre- ~"^v^ 



vent, and was de- f,g. i. ~ 



signed to prevent, 



a following contact, and insures a breaking of 

 the circuit when the distance of the point is 

 properlj- adjusted. The same is the case with 

 the form of transmitter illustrated in fig. 2. 

 In the form represented in fig. 3, the screw 

 is present, and works against a spring ; but 

 the screw passes through a stout and firm piece 

 of metal, and presses the spring which carries 

 the contact-piece forward, that is, toward the 

 membrane, thus giving it a rigid support. The 

 spring serves merely to push back the con- 



tact-piece wlien the screw is reversed, a very 

 simple and common mechanical dcvicJ for giv- 

 ing motion in opi)osition to the thrust of a screw. 

 In the lever form, seen in figs. 4 and 5, the 



