THE ELECTROLYSIS OF WATER. gg 
ments of Mr. Grove very nearly represent the 
affinity of the positive metals for oxygen which is 
not in the gaseous state. For the separation of 
the hydrogen from the oxygen of the water is 
simultaneous with the union of hydrogen with 
the oxygen which may almost be regarded as free 
at the platinum. And these actions neutralizing 
each other, it follows, that the intensity of the 
current very nearly represents the affinity of the 
positive metals for oxygen. 
But with the pairs on Mr. Smee’s arrangement, 
there are two things opposed to this affinity. One 
of them is the separation of the elements of water 
from each other, whilst the other is the giving 
hydrogen the gaseous form. Hence we have 
1°732—0°731=1:001, and 1:14—0°149=0-991. 
We shall take 1, (which is very nearly the mean 
of these,) for the intensity necessary to take 
hydrogen from oxygen, and to give it the gaseous 
form. 
Again, I placed platinum wires in a solution of 
sulphate of oxide of zinc, and, connecting them 
with the long wired galvanometer, I found the 
currents which passed when 3 and 4 pairs of 
Daniell were used, to be in the ratio of 160 to 
