electricity resulting from the discharge of the cells; moreover, the
battery can be carried from one place to another without injury. A
battery was lately charged in Paris, then taken to Brussels, where it
was used the next day without recharging. The cost is also said to be
very low. A quantity of electricity equal to one horse power during an
hour can be produced, stored, and delivered at any distance within 3
miles of the works for 11/2d. Therefore these batteries may become useful
in producing the electric light in private houses. A 1,250 horsepower
engine, working dynamo-machines giving a continuous current, will in one
hour produce 1,000 horse-power of effective electricity, that is to
say 80 per cent. of the initial force. The cost of the machines,
establishment, and construction will not be more than L40,000, and the
quantity of coal burnt will be 2 lb. per hour per effective horse-power,
which will cost (say) 1/2d. The apparatus necessary to store up the force
of 1,000 horses for twenty-four hours will cost L48,000, and will weigh
1,500 tons. This price and these weights may become much less after a
time. The expense for wages and repairs will be less than 1/4d. per hour
per horse-power, which would be L24 a day, or L8,800 a year; thus the
total cost of one horse-power for an hour stored up at the works is
3/4d. Allowing that the carriage will cost as much as the production and
storing, we have what is stated above, viz., that the total cost within
3 miles of the works is 11/2d. per horse-power per hour. This quantity of
electricity will produce a light, according to the amount of division,
equivalent to from 5 to 30 gas burners, which is much cheaper than
gas.--_Chemical News_.

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