252 POWER DISTRIBUTION FOR ELECTRIC RAILROADS.
Intramural line during the Columbian Ixposition, and
subsequent results on the Metropolitan and Lake Street
elevated roads in Chicago, have shown, what theoretical
investigation had indicated, that for such service electric
power is the cheapest available means of propulsion.
Elevated serviceis of a rather trying nature on account
of the frequent stops—generally about every quarter of a
mile—and the large amount of power that has to be used
MAP OF
THE METROPOLITAN
WEST SIDE ELEVATED R. R.
Chicago, lllinois
ND A AVE.
54 LAWNDALE
o]
W.48TH.ST.
CRAWFORD J|| AVE.
Douglas Park
Street Ry Journal
FIG. 128.
in acceleration. The experimentsof Mr. Sprague made on
the Third Avenue elevated road in New York established
the facts very clearly. It was found that for .the ordinary
train, weighing from eighty to ninety tons, with a speed
reaching, between stations, twenty to twenty-five miles per
hour, the average indicated horse power of the locomotives
during service was 70.3 reaching an occasional maximum
of 185. 'These great inequalities almost vanished when the
whole power for the line was considered. Sixty-three
trains were in ordinary use and the mean power, smoothed
out by the large number of units, varied little from 4500 in-
L T T LA RN (L PO R TR TR 7O T e
S
TR TR e