movement united the four series in quantity, coupling
them on each other, and putting the dynamo out of circuit, thus restoring
equilibrium. When in a state of repose, the handle was so arranged as to
keep this latter switch turned on. The accumulators were arranged for
charging in two series united in quantity, each containing twenty double
elements. The charge was effected by a Gramme machine, worked by a
portable engine. Each of these series received its charge during seven
hours for the ordinary service of the car, and during nine hours for the
accelerated service.

The accumulators on the car actuated a Siemens dynamo, acting as a motor,
such as is used for lighting, having a normal speed of 1,000 revolutions,
fixed on the frame of the carriage. The motion was conveyed from the
pulley on the dynamo by means of a belt passing round a shaft fixed on
movable bearings to regulate its tension, and thence to the axles by
means of a flat chain of phosphor bronze. The chain was adopted as the
means of moving the axle, on account of its simplicity and facility of
repair by unskilled labor.

The speed was fixed at 4 meters per second (which corresponds with a
speed of nearly 9 miles per hour) for 1,000 revolutions of the dynamo;
and it was regulated by cutting a certain number of the accumulators out
of circuit, instead of by the device of inserting resistances, which
cause a waste of energy. By breaking the circuit entirely the motive
power ceased, and the vehicle might either be stopped by the brakes or
allowed to run forward by gravity, if the road were sufficiently
inclined. The reversal of the motor was effected by means of a lever
which reversed the position of the brushes of the dynamo.

The dynamo could be set in motion, and the carriage worked from either
end, as desired. The handle to effect this was movable, and as there was
only one handle, and this one was in charge of the conductor, he used it
at either end as required.

It should be mentioned that the car was lighted at night by two
incandescent lamps, which absorbed 1.5 amperes each; and the brakes also
were worked by the accumulators.

The weight of the tram-car was 5,654 lb.; the weight of the accumulators
was 2,460 lb.; the weight of the machinery, including dynamo, 1,232 lb.
The car contained room for fourteen persons inside and twenty outside.
Under the conditions of the competition the car was required to draw a
second car occasionally.

The jury