736 REPORT—1885. 
And all this is exactly borne out by the above scheme: for one notes that 
3 atoms of acid make their appearance in the anode vessel and 1 atom 
in the cathode vessel; that 4 an atom of O is transferred one way, and 
4 an atom of H, the other way; that } atoms of Cu travel from anode 
vessel to cathode vessel, but that 4 are deposited, making the net loss 
in this vessel 4 — 15 = 2}; and so on. 
Modification of the above table by the introduction of Kohlrausch’s 
hypothesis that each ion has its own rate of travel. 
Consider now what will happen if, instead of assuming that opposite 
corresponding ions must go at the same pace, we assume that each has its 
own pace ; and that the sharing of the current between the ingredients 
of the fluid depends on these intrinsic ionic velocities and on the propor- 
tion of each substance present. 
Of the two compounds AC and A/C’, we must affix a mass-velocity to 
each ion—say, a, y, a’, y’, respectively ; so that 
a + y is what we formerly called A, 
and a’ + y! 9 » Nv; 
but no longer does a = 43. So the above table becomes :— 
Results of Double Electrolysis, §c. 
Loss in cathode 
Substance socal Loss in anode vessel Total loss 
A a —@ 0 
Al a’ l—a 1 
Cc cy Y 1 
Cc’ hy 7’ 0 
AC 1-y y 1 
A'C! a! a" 1 
AC’ —(a’ +7) —(a+7) —] 
This gives the relative formation ¢ free acid in the two vessels exactly 
he ae 
nae 
It is a trifle more general than the former hypothesis, in the non- 
equality of a and y, and of uw’ and y’, and this fact may furnish a method 
of distinguishing between the two hypotheses. 
From the table we see a way to find these values, thus: 
the same as before—viz. 
y = loss of AC in the anode vessel, 
a’ = loss of A’C’ in the cathode vessel, 
a + y = gain of AC’ in the anode vessel, 
‘and atyta+y=l1. 
In Kohlrausch’s theory, indeed, ionic velocities are supposed to be 
pretty well known, and accordingly we may seek to compare the relative 
quantity of free acid, found in the two vessels, with the ratio At Y 
see y, 
But then Kohlrausch’s velocity-numbers are founded on a strictly Hit- 
torfian view of migration, and do not depend on the assumed conductivity 
of all the ingredients present in a fluid: they are intended to stand for 
