MR. DANIELL ON VOLTAIC COMBINATIONS. 
143 
was then filled with water at 120°. When the temperature of the interior cell had 
reached 100° a slow action commenced, which became steady at 0'6 cubic inches per 
five minutes. The voltameter itself being now also heated to 1 15°, the following re- 
sults were obtained : 
Time. 
h m 
11 21 
Interval. 
Voltameter. 
Cubic inches. 
5 min. rate. 
Cubic inches. 
11 26 
5 
0*8 
0-8 
11 31 
10 
1*6 
0-8 
11 51 
30 
5*0 
0-8 
At the expiration of the experiment the rods were found to be only slightly tarnished, 
and no copper had penetrated to the interior cells. 
The next charge which I made trial of was a solution of muriate of ammonia, in 
the proportion of two pounds of the salt to a gallon of water for the interior cells, 
and aqueous solution of sulphate of copper for the exterior. The results were as 
follow : 
per 5 min. 
0 Cubic inches. 
At 74 out of water 5-5 
At 94 in water 8 - 8 
At 124 in water 125 
Upon this occasion I first observed that a portion of the current was discharged by 
the water in which the battery was immersed. 
The battery plunged in water of the atmospheric temperature of 74° had been 
working steadily for twenty minutes at the rate of 3T cubic inches per five minutes : 
when the water was drawn off from the tub the rate immediately rose, and was 
maintained at 4*2 cubic inches per five minutes. 
That a discharge may take place from the copper of one cell to the copper of the 
next, when the regular circuit is interrupted between the two, I had many opportu- 
nities of observing in the powerful currents with which I had been experimenting ; 
for I have frequently seen it pass in the form of a spark when the cells had been too 
much approximated in the air ; and when in water it was indicated by the frothing 
between the two from the disengagement of gas. In such a case there is no doubt 
that one of the zinc rods is thrown out of action, and the copper of that cell merely 
acts as an electrode to the antecedent zinc. I shall hereafter point out to you how 
readily a portion of a current may be diverted from its principal course to by-paths, 
if I may so express myself, which may be open to it. 
The decomposition of the secondary electrolytes, and the course of the ions in this 
combination, are worthy of some remark. In several instances when the battery had 
been in action for a considerable period, the zinc rods were found thickly studded 
with beautiful, large, transparent crystals of sulphate of zinc. The solution of this 
