ELECTRIC DISCHARGE WITH THE CHLORIDE OP SILVER BATTERY. 107 
On one occasion, with coil 815, in connexion with coil C of 350 yards, 0*028 microfarad, 
as a condenser, and 3240 powder cells, which evolved 0\3 cub. centim. mixed gases 
per minute in the voltameter, 3-inch sparks were obtained, with a moderate rotation 
of the contact breaker. 
Apps’s No. 821 coil, either with its own condenser or -fths of Ladd’s condenser, D 2 
= 0*1807 microfarad, produces a rapid succession of 6-inch spai-ks when worked with. 
6 cells in series of a zinc-carbon battery, charged with a solution of bichromate of 
potash and sulphuric acid, the plates being 12 inches by 5 inches, and each zinc 
between two carbon plates ; the make-and-break being effected automatically by the 
usual hammer- and- anvil arrangement. This battery evolved 152 cub. centims. of mixed 
gases per minute, when the current passed through a voltameter having a resistance of 
17 ohms, and containing a mixture of 1 part sulphuric acid and 10 of water. The 
chloride of silver battery evolved only 0*5 cub, centim. of mixed gases under the 
same circumstances, consequently only -g-g-yth part ; nevertheless, as great or even 
greater effects were obtained with it than those with the zinc-carbon battery. 
With 1080 cells and the Ladd condenser D 2, 0‘4518 microfarad, connected per- 
manently with the battery, a dense spark, 3 '5 inches long, was obtained on making 
contact with the key, so as to send the accumulated charge through the primary of 
the coil, but only a feeble spark on breaking contact. 
With 2280 oells and condenser D 2, under the same circumstances, a full 6 -inch 
spark was obtained, and a rapid succession of such sparks, when the break-wheel made 
44 contacts in a second. 
With 3480 cells, on making contact, the same effects, and a rapid succession of such 
sparks when the break- wheel made 62 makes-and-breaks in a second. 
It seemed probable that the battery could charge up larger condensers with sufficient 
rapidity, and this was shown to be the case by the following experiments : — - 
With 3480 cells and condensers D 2 and D 3, 0 - 9222 microfarad, dense sparks not 
only passed between the terminals of the secondary coil, but other sparks, longer than 
6 inches, jumped from every part of the coil when the. break-wheel made 212 contacts 
in a second. 
With the same number of cells and condensers D 1, 2, 3, 4, 1*4887 microfarads and 
352 breaks in a second, the sparks were as long, but denser, than in the last-named 
case. 
It appears from the foregoing experiments that a high potential is very favourable 
to the production of induction effects when used in connexion with accumulators of 
suitable capacity. The accumulated high-tension charge passes at each make contact, 
and produces effects partly dependent on the potential and partly on the quantity of 
current, which must be, however, considerably less in a given time than that when a 
battery of large plates is employed (6 zinc-carbon cells, 12X5 inches). 
Although it was not anticipated that the production of these exalted effects in 
comparison with the current was due to any effect with regard to the induced magnetism 
p 2 
