Voltaic Circles produced by Acid and Alkaline Fluids. 489 



Transactions (continued). 



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" On the Voltaic Circles producible by the mutual Neutrali- 

 sation of Acid and Alkaline Fluids, and on various related 

 Forms of Electromotors." By C. R. Alder Wright, D.Sc, 

 F,R.S., Lecturer on Chemistry and Physics, and C. Thomp- 

 son, F.I.C., F.C.S., Demonstrator of Chemistry, in St. 

 Mary's Hospital Medical School. Received January 18, 

 —Read February 2, 1888. 



(Abstract.) 



The authors have examined a variety of cells analogous to 

 Becquerel's " pile aoxygene; " i.e., containing two platinum or other 

 non-oxidisable plates, one immersed in an acid fluid, the other in an 

 alkaline one, the two fluids being connected by a wet wick or siphon, 

 and either some oxidising agent being also contained in the acid or 

 some reducing substance in the alkali. In the first case continuous 

 evolution of oxygen was brought about from the surface of the 

 plate immersed in the alkali ; in the second the converse phe- 

 nomenon was observed, i.e., hydrogen was continuously evolved 

 from the plate in the acid ; in each case the quantity of gas liberated 

 was equivalent to the current passing as measured by a small silver 

 voltameter. Thus the following figures were obtained in various 

 experiments, the measurements being made after sufficient amounts 



