The battery shown, in Lombard Street consisted of fifteen cells arranged
in three boxes of five cells each. Each box measured about 18 in. by
12 in. by 10 in., and weighed from 75 lb. to 100 lb. The electromotive
force of each cell was 1.8 volts and its internal resistance from 1/40
to 1/50 of an ohm, consequently the battery exhibited had, under the
must favorable circumstances, a difference of potential of 27 volts at
its poles, and a resistance of 0.3 ohm.

When connected to a group of ten Swan lamps of five candle power,
requiring a difference of potential of 20 volts, it raised them to vivid
incandescence, considerably above their nominal capacity, but it failed
to supply eighteen lamps of the same kind satisfactorily, showing that
its working capacity lay somewhere between the two. A more powerful lamp
is used in the railway carriages, but as there was only one erected it
was impossible to judge of the number that a battery of the size shown
would feed. _Engineering_ says the trial, however, demonstrated that
great quantities of current were being continuously evolved, and if,
as we understood, the production can be maintained constant for about
twenty-four hours without attention, the new battery marks a distinct
step in this kind of electric lighting. Of the construction of the
battery we unfortunately can say but little, as the patents are not yet
completed, but we may state that the solid elements are zinc and
carbon, and that the novelty lies in the liquid, and in the ingenious
arrangement for supplying and withdrawing it.

Ordinarily one charge of liquid will serve for twenty-four hours
working, but this, of course, is entirely determined by the space
provided for it. It is sold at sevenpence a gallon, and each gallon is
sufficient, we are informed, to drive a cell while it generates 800
ampere hours of current, or, taking the electromotive force at 1.8