NTERURBAN AND CROSS COUNTRY WORK. 2IQ
A twenty-four inch gauge track, laid with thirty
pound rails, can be put down under favorable circum-
stances for about $3500 per mile. Then comes the bond-
ing and the erection of the overhead structure. The
amount of wire required for such a line is comparatively
small, for the power also is small.
For a line ten miles in length, two trains in steady
service, each consisting of a light motor car and a freight
skip, would meet all ordinary requirements. The total
weight, loaded, should not often exceed ten tons. To drag
this load on a level track at eight miles per hour requires
about seven horse power at the car wheels. As grades
would naturally be taken at a somewhat lower speed, the
power required would not increase very greatly, and an
expenditure of fifteen horse power at the wheels would
seldom have to be exceeded.
B D Street Ry.Journal
RO 11
In reckoning the copper we should have to allow for
the delivery of about thirty amperes to the train. With
600 volts initial pressure, and allowing one hundred volts
drop at the end of the line, it appears that the copper re-
quired is trifling. Using 13 as the constant in our stock
formula, the wire, supposing the station to be at the cen-
ter of the line, comes out No. o, which may conveniently
be suspended as the trolley wire.
For economy bracket construction should be used,
unless circumstances require cross suspension, in which
case the very neat diagonal suspension, due to J. C. Henry,
is the cheapest and most convenient method for light
work. ‘Thisis showninFig.113. Here A, B, C, D, E, etc.,
are the poles set in the usual way, 100 to 125 ft. apart, but
alternately on either side of the track. The suspension
wire is strung from pole to pole, as shown, and the trolley