n extent, an
estimate; because the engine which furnished the electricity to the motor
also supplied electricity for electric lights, as well as for an
experimental electric motor which was running on the lines of tramway,
but was not brought into competition.

20. Minimum consumption of oil, of grease, tallow, etc. (the same
conditions as in No. 19).

TABLE V.

Total Consumption
Total consumption of oil, tallow,
Description of number of of etc.,
motor. miles run. oil, tallow, per train mile
etc. run.

lb.
Electric 2,358.9 99.0 0.038
Rowan, steam 2,616.9 106.7 0.038
Krauss, steam 2,457.8 188.5 0.073
Wilkinson, steam 2,473.3 255.4 0.101
Compressed air 2,259.1 585.2 0.255

In addition to these considerations, it was thought useful to investigate
the quantity of water consumed in the case of those engines which used
steam. The experiments made on this point showed as the consumption of
water:

Gallons per mile.
Rowan 0.75
Compressed air 1.06
Wilkinson 5.89
Krauss 6.52

Thus, owing to the large proportion of water returned from the condenser
to the tanks, the Rowan actually used less water than the compressed air
engine.

CONCLUSION.

The general conclusion to which these experiments bring us is that,
undoubtedly, if it could certainly be relied upon, the electric car would
be the preferable form of tramway motor in towns, because it is simply a
self-contained ordinary tram-car, and in a town the service requires a
number of separate cars, occupying as small a space each as is compatible
with accommodating the passengers, and which follow each other at rapid
intervals.

But the practicability and the economy of a system of electric tram-cars
has yet to be proved; for the experiments at Antwerp, while they show the
perfection of the electric car as a means of conveyance, have not yet
finally determined all the questions which arise in the consideration of
the subject. For instance, with regard to economy, the engine employed to
generate the electricity was not in thoroughly good order, and from its