XI. APPLICATIONS. 367 



1576u. Polarised Morse with Wheatstone's System 

 of Adjustment and Inking. 



The British Telegraph Manufactory, Limited. 



1576v. Translating Morse with Wheatstone's System 

 of Inking. The British Telegraph Manufactory, Limited. 



1576w. Resistance Box. 



The British Telegraph Manufactory, Limited. 



1576x. Resistance Box. 



The British Telegrdph Manufactory, Limited. 



1576y. Large Standard Resistance Box. 



The British Telegraph Manufactory, Limited. 



1576z. Commutator. 



The British Telegraph Manufactory, Limited. 



1582. Meidinger's Galvanic Element. 



Prof. Dr. Meidinger, Carlsruhe. 



1583. Meidinger's Galvanic Element (larger size). 



Prof. Dr. Meidinger, Carlsruhe. 



For working telegraphs, electric clocks, and bell apparatus, also for electro- 

 plating in silver or gold. 



1584. Box, containing a battery of 21 elements for pro- 

 ducing constant currents for medical use. Entirely new con- 

 struction of the exhibitor. Prof. Meidinger, Carlsruhe. 



The glasses are filled with a solution of bichromate of potash and 

 sulphuric' acid in water. The gutta-percha covered rods are introduced into 

 the wide glass, and the wires into the mercury tube, with which is connected a 

 platinum wire, leading to the platinum sheets, After working the metal con- 

 nexions are taken out of the glasses. The liquid is allowed to remain in the 

 glass till it is exhausted; it may serve for 100 one-hour operations. In 

 transport, the liquid does not escape, even in violent shaking. The stoppers 

 with inserted glasses are never taken out. Filling is accomplished .by pouring 

 the liquid through the wide tube ; emptying by inverting the glass, when the 

 liquid flows out through the fine air passages. The gutta-percha under the 

 zinc is gradually worn away in proportion as the (amalgamated) zinc is dis- 

 solved; only about a millimetre of free surface of zinc is necessary. The 

 narrow trough is filled with very dilute zinc vitriol, and serves for regulating 

 the strength of current by displacement of the zinc pole. On drawing out a 

 peg, the liquid escapes below into a central vessel. 



1585. Colour-writer (Morse), North German pattern. 



L. E. Schwerd, Carlsruhe. 



This is furnished with contact-arrangement for translation, and with 

 commutator for sending the current through both electro-magnet coils either 

 successively or simultaneously ; in the latter case the resistance of the coils 

 should be only ^. 



1586. Box Relay, N. German pattern. 



L. E. Schwerd, Carlsruhe. 



