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Prof. A. Schuster and Mr. A. W. Crossley. [Jan. 21, 



V. "On the Electrolysis of Silver Nitrate in Vacuo." By 

 ARTHUR SCHUSTER. F.R.S., and ARTHUR W. CROSSLEY, 

 B.Sc. Eeceived January 5, 1892. 



The following investigation was undertaken in order to clear up 

 some minor irregularities which occur when the intensity of an 

 electric current is measured by means of a silver voltameter. 



The electrolysis of silver nitrate yields with moderate precautions 

 such very consistent results that it seemed of interest to follow up 

 the small apparent deviations from Faraday's laws which are found 

 to exist. One of these irregularities has been noticed by Lord Ray- 

 leigh, who found that the deposit of silver from a hot solution was 

 about one part in two thousand heavier than the deposit from a cold 

 solution. A second anomaly lies in a small but regular discrepancy 

 in the deposits when these are taken simultaneously in platinum 

 bowls of different sizes ; the difference, according to our experiments, 

 seems to depend on the current density at the anode. But the chief 

 part of this paper will deal with the fact discovered by us, that the 

 deposits are slightly larger when the electrolysis is conducted in 

 vacuo than when, as usual, the voltameters are exposed to air at the 

 ordinary pressure. This difference we trace to the effects of dissolved 



FJG.I. 



