96 Mr. Napier on the- unequal Decomposition of Electrolytes, 



1 and 2 pairs of large and small plates ; but two porous 

 vessels were used, put into a vessel charged with the same 

 liquid as the positive, the negative in this, as in the last, being 

 charged with sulphate of copper, the electrodes being 2 by 

 2\ inches in all the experiments. 



1st. Positive solution, sulphuric acid ] to 24 water. 



1 pair small plates deposited 9 grains, dissolved 1 1 grains ; 

 equivalent 7 grains. 



1 pair large plates deposited 9 grains, dissolved 12 grains* 

 equivalent 10*6 grains. 



2 pairs small plates deposited 16 grains, dissolved 18 grains ; 

 equivalent 4 grains. 



2 pairs large plates deposited 19 grains, dissolved 22 grains ; 

 equivalent 5 grains. 



2nd. Positive solution, muriatic acid 1 to 24 water. 



1 pair small plates deposited 5 grains, dissolved 6 grains ; 

 equivalent 6*3 grains, 



1 pair large plates deposited 7 grains, dissolved 9 grains • 

 equivalent 9'1 grains. 



2 pairs small plates deposited 9 grains, dissolved 12 grains; 

 equivalent 9 '4 grains. 



2 pairs large plates deposited 1 1 grains, dissolved 16 grains ; 

 equivalent 14'5 grains. 



3rd. Positive solution, nitric acid 1 to 24 water. 

 1 pair small plates deposited 8 grains, dissolved 9 grains ; 

 equivalent 4 grains. 



1 pair large plates deposited 8 grains, dissolved 10 grains; 

 equivalent 8 grains. 



2 pairs small plates deposited 14 grains, dissolved 15 grains ; 

 equivalent 2*3 grains. 



2 pairs large plates deposited 19 grains, dissolved 21 grains ; 

 equivalent 3*3 grains. 



I now took three separate pairs of small plates excited by 

 1 sulphuric acid to 24 water, and to each attached copper 

 electrodes, which were placed in a solution of sulphate of 

 copper : the electrodes of one were one-half size of the battery 

 plates, of the other equal size, and of the third twice the size 

 of the battery plates. The current passed sixteen hours, the 

 results were as follows : — 



Small negative electrode gained 25*4 grains, positive lost 

 29*3 grains ; equivalent 4*9 grains. 



Equal-sized negative electrode gained 33 grains, positive 

 lost 37 grains ; equivalent 3*8 grains. 



