206 POWER DISTRIBUTION FOR ELECTRIC RAILROADS.
It is advisable, however, to use a larger trolley wire than
usual, not at all to secure larger area of contact with the
trolley, for this is needless, but to simplify the feeding
system. The larger the trolley wire, the easier it is to
equalize the voltage along the line. Nothing smaller than
No. oo should be used and No. ooo or No. oooo may often
be useful. These larger sizes require special precautions
in suspension. but sometimes are worth the trouble. In
most interurban work the bracket suspension can be freely
used and is advisable, being cheaper and easier to keep up
than the crosswire suspension.
HIG L ETO;
The supply of power to an interurban line can best
be illustrated by working out the details of a concrete
case. We may take for thisthe hypothetical line discussed
at the end of the last chapter, selecting for discussion the
first case, using two stations for the line.
Fig. 1111s a diagram of the system. Here A and B are
the termini, C and D intermediate towns which may have an
influence on the distribution of the power and E and F the
points selected for the power stations in Chap. VII. ‘The
track is, as will usually be the case in such roads, a single
track with turnouts. The distance from A to B is thirty
miles, from A to C about five miles and from D to B twelve
&