284 



M. G. Quincke on Electrolysis, and the 



in water and alcohol, Hittorf*, Wiedemannfj and WeiskeJ de- 

 termined the composition of the liquid near the electrodes, both 

 before and after the passage of the electrical current; and at the 

 same time, assuming Faraday's electrolytical law, they deter- 

 mined the intensity of the current by means of the quantity of 

 silver or copper liberated in a voltameter by the same current. 



With very few exceptions, to which 1 shall presently return, 

 the passage of the electrical current produced a decrease of the 

 concentration of the solution at both electrodes. Therefore the 

 relation 11« (§ 54) holds, 



M<m, W<m'-, 



or e end e' have opposite signs, and the two partial molecules 

 move in the electrolyzed thread of liquid in opposite directions. 

 In Wiedemann's ^ Galvanism,^ vol. i. pp. 356-361 and p. 383, 

 there is a tabulated collection of the results obtained by the 

 above-named observers. If the number of equivalents of partial 

 molecules which accumulate on the cathode for 1 equivalent of 

 the metal separated in the voltameter be denoted by n, on the 

 anode by ti', then the experiments, in agreement with the theo- 

 retical considerations of § 54, give 



and n and n^ independent of the density of the current. 



The following Table contains a collection of the results ob- 

 tained by the different observers : n and n' have the meaning 

 just indicated, but P denotes the weight of water which was con- 

 tained in the solution for 1 part by weight of salt. 



Salt. 



Hittorf. 



Wiedemann. 



P. 



n'. 



P. 



n\ 



AgNO^I 



5415 



23-36 

 14-50 

 49-44 



0174 



0-177 

 0-525 



0-526 



1306 

 21-12 

 19-73 

 52-58 



0177 

 0-163 

 0-494 

 0-507 



1 





P. 



n. 



P. 



i 

 n. 



CuSO^ - 



18-08 

 39-67 

 76-88 



0-325 

 0-355 

 0-349 



26-37 

 3207 

 44-19 



0333 

 0-323 

 0-363 



* Pogg. Ann. vol. Ixxxix. pp. 177-211 (1853); vol. xcviii. pp. 1-33 

 (1856); vol. ciii. pp. 1-56 (1858); vol. cri. pp. 337-411, pp. 513-586 

 (1859). 



t Ibid. vol. xcix. pp. 177-215 (1856). 



X Ibid. vol. ciii. pp. 466-486 (1858). 



