The loss of energy from standing about is probably nothing. If a
battery were to stand charged for three months in a dry case, the loss
of energy might be in three months 10 per cent. I purposely had a set
of cells standing for two years charged and never used them. After two
years there was still a small amount of energy left. So as regards
the loss of energy in a battery standing idle, it is practically
nothing, because no one would think of charging a battery and letting
it stand for three months or a year.

I have had them stand three or four months and I could hardly
appreciate the loss going on, provided always that the cells are
standing on a dry floor. If the exterior of the box be moist, or if it
stands on a moist floor, there will naturally be a surface leakage
going on: but where there is no surface leakage the mere local action
between the oxides and metallic lead will not discharge the battery
for a very considerable time.

I have made experiments in London with a loaded car pulled by two
horses. I put a dynamometer between the attachment of the horse and
the car, so as to ascertain exactly the amount of pull, measured in
pounds multiplied by the distance traversed in a minute. You will be
surprised to know that two horses, when doing their easiest work,
drawing a loaded car on a perfectly level road, exert from two to
three horse power. I have mentioned a car in Philadelphia where we use
between two and twelve horse power. A horse is capable of exerting
eight horse power for a few minutes, and when a car is being driven up
grades, such as I see in Boston, for instance, pulling a load of
passengers up these grades, the horses must be exerting from 12 to 16
horse power, mechanical horse power. That is the reason that street
car horses cannot run more than three or four hours out of the