MR. DANIELL ON VOLTAIC COMBINATIONS. 
145 
them in their proper positions ; the perforated copper plates, or colanders, for the 
reception of the solid sulphate of copper, pass over their upper ends. The tubes can 
be easily removed and instantly replaced ; and the facility of emptying- and refilling 
them renders the addition of syphon tubes unnecessary, except in very particular cir- 
cumstances. Previously to their use they require to be thoroughly soaked in dilute 
acid ; and I have not found them liable to injury, provided the sulphate of zinc be 
not allowed to crystallize within them ; in which case they become disintegrated 
from the expansive force of crystallization. When the battery is out of action they 
may always be removed and emptied, and preserved in a state for immediate use by 
immersing them in very dilute acid. Liquid conduction is not carried on quite so 
perfectly through their substance as through the membranes, on account of the less 
perfect communication between the liquids on their opposite sides ; but when the 
acid sulphate of copper is used the amount of action at ordinary temperatures is 
from 7 to 8 cubic inches per five minutes, which is quite sufficient for all ordinary 
purposes, and is moreover perfectly constant and steady. 
Having thus prepared the battery, I caused a circular steam vessel to be made of 
tin plate, round which the cells could be placed upon blocks of wood, and closed in 
with a cover, in which there was a socket which could at pleasure be connected with 
the steam pipe of a boiler. Two other sockets were also conveniently placed, which 
were stopped with corks, through which the electrodes of the battery could pass, 
when the proper connections were made. I intended to have experimented with a 
series of ten cells, but owing to a mistake only nine could be conveniently arranged 
in the steamer. 
The general result of numerous experiments was, that, the working rate of the 
battery having been ascertained at the ordinary atmospheric temperature, when 
steam was admitted it immediately began to rise; and at the full temperature of 212° 
was more than doubled, provided no secondary action interfered with it. The fol- 
lowing series will be sufficient to illustrate the progress of the current : the tempera- 
tures were taken by a thermometer immersed in the steam. 
Time, 
h m 
10 0 
Interval. 
/ 
Voltameter. 
Cubic inches. 
5 min. rate. 
Cubic inches. 
Temperature. 
O 
10 5 
5 
7-5 
7-5 
58 
10 10 
10 
15- 
7-5 
58 
10 25 
Steam admitted 
. . . . 
. 110 
10 30 
5 
9- 
9- 
170 
10 35 
10 
205 
11-5 
195 
10 40 
15 
37' 
165 
200 
10 41 
10 46 
5 
19- 
19- 
205 
10 51 
10 
39* 
20- 
206 
MDCCCXXXVII. 
u 
