1054 



Voltaic Electricity. Section 11 : Telephony and Microphony. 



No. 63360 



53 587 B. 1:4. 



53 587 A. 1 = 4. 



63 360. 1 : 7. 



63362. 1:4. 



63 369. 1 : 4. 



Section 11: Telephony and Microphony. 



53,587. Telephone after Ph. Beis, consisting of transmitter, Fig. 53.587 A, and Eeceiver, 

 Fig. 53,587B 



Between transmitter and receiver called by Reis himself the reproducing apparatus a bat in y 

 is so connected up that the two are traversed in series by the current. The latter should be of such 

 strength that the armature of the small magnet on the transmitter is attracted; for this purpose 

 3 4 Bunsen cells or storage cells should suffice, according to the distance between both stations. 



63.360. Apparatus for Explaining the Working of the Telephone, Figure (Ztschr. f. d. 

 phys. u. chem. IT. 2, p. 133; Kolbe, Einf. i. d. Elektrizitatslehre, Vol. 2, Fig. 78 A) 



The apparatus consists of two powerful bar magnets on to which two wire coils are slipped; the 

 coils are connected with each other. In front of one of the magnets a small iron piece is suspended 

 so as to be capable of oscillation. If the thick iron plate given in with the apparatus is brought up 

 to the other magnet at regular intervals (say, to the beat of the pendulum oscillation) until it makes 

 contact, and is then removed, the small iron piece in front of the first magnet is set into oscillatory 

 motion, which can be increased until the iron piece is finally attracted by the magnet. 



63.361. Telephone in Glass Case. Figure, with ebonite mountings; all internal parts quite 

 visible ' 



63.362. Telephone after Bell, Figure, in ebonite sheath with double flexible 



63,367. Round Pattern Telephone, F i g u r e, double-pole, with niekelled cap, ebonite mouth- 

 niece and twin flexible 



63.369. Receiver with lateral ear-piece, F i g u i e, with horse-shoe magnet, niekelled di.i- 

 plintgm case, ebonite piece and twin flexible 



63.370. Precision Telephone, Figure, thoroughly well constructed 



63.373. 20 metres Twin Flexible, with wire ends for connecting up two telephones . . 



63.374. Microphone after Weiuho'd, simple, Figure (W. I). Fig. 600 [549J) 



63.375. Microphone after Hughes. Figure (M. P., <l lh Kdn., Ill, Fig. 800) 



s. d. 

 4. 0.0 



2. 2.0 



0.16.0 

 0.12.0 



0. 8.0 



(). 16.0 



1. 0.0 

 0. 6. 

 0. 6.0 



Cl. 1178, 3066 

 1177, 

 3500, 3067 



0. 8. 



3068, 



3069. 



