In the electric tram-car the haulage was effected by means of accumulators.  The car was of the ordinary type with two platforms.  It was said to have been running as an ordinary tram-car since 1876.  It had been altered in 1884 by raising the body about six inches, so as to lift it clear of the wheels, in order to allow the space under the seats to be available for receiving the accumulators, which consisted of Faure batteries of a modified construction.  The accumulators employed were of an improved kind, devised by M. Julien, the under manager of the Compagnie l’Electrique, which undertook the work.

The principal modification consists in the substitution, for the lead core of the plates, of one composed of a new unalterable metal.  By this change the resistance is considerably diminished, the electromotive force rises to 2.40 volts, the return is greater, the output more constant, and the weight is considerably reduced.  The plates being no longer subject to deformation have the prospect of lasting indefinitely.  The accumulators used were constructed in August, 1884.

The car, as altered, had been running as an electric tram-car on the Brussels tramways since October, 1884, till it was transferred to the experimental tramway at Antwerp.  The accumulators had been in use upon the car during the whole of this period, and they were in good order at the end of the experiments, that is to say, when the exhibition closed at the end of October, 1885.

The accumulator had forty elements, divided into four series, each series communicating, by means of wires fixed to the floor of the car, with commutators which connected them with the dynamo used as a motor.

There were two sets of these batteries or accumulators, one of which was being charged in the shed while the other was in use.  The exchange required ten minutes, including the time for the car to go off the tramway into the shed and return to the tramway.  This exchange took place after every seven journeys.  Therefore, the two batteries would have sufficed for working the car over a distance of about forty-two miles during sixteen hours.

It may be observed that the first service in the morning would be performed by means of the accumulators charged during the afternoon and evening of the previous day.

Each element of a battery was composed of nineteen plates, of which nine were positive, four millimeters thick, and ten negative, three millimeters thick.  Each positive plate weighed 1.44 lb., of which about twenty-five per cent. consisted of active material.  Each negative plate weighed nearly 1 lb., of which one-third consisted of active matter.  The weight of the metallic part of the battery amounted, therefore, to 1,846 lb.; and the whole battery, including the case and the liquid, amounted to 2,464 lb., which contained 499 lb. of active matter, or about 20.25 per cent.  The four cases in which the battery was contained were so arranged as to divide the weight equally between the wheels.