FAST AND HEAVY RAILWAY SERVICE. 243
By far the most interesting line of advance in electric
railway work is toward long distances at very high speeds.
The idea of clipping the wings of T'ime by doubling our
present railway speeds is a very attractive one, not lightly
to be cast aside as chimerical.
The problem naturally divides itself into three queries:
Can it be done? How can it be done? Will it pay? As re-
gards the first question we are now in a position to give a
definitely affirmative answer. Suppose we set for our goal
a schedule speed of one hundred miles per hour. Under
the conditions which may be expected to obtain with ex-
press service, the corresponding maximum speed would not
have to be very high, probably not over 120 miles per hour.
Obviously the attainment of such speed depends on
only two things—the delivery of sufficient power to the
moving locomotive, and the mechanical security of track
and rolling stock. In our present express service both
here and abroad trains have within the past few years re-
peatedly run on nearly level track at the rate of one hun-
dred miles per hour and its immediate neighborhood.
This speed has not been maintained for more than a few
miles at a time, but it has been accompanied by *no special
phenomena in the way of vibration, strain on track and
rolling stock or rapid increase of resistances. In fact the
motion at these high speeds seems to be smooth and the
track resistances, if anything, are less than at more moder-
ate speeds. Air resistance, once much dreaded, is not very
serious, for indicator cards from locomotives drawing trains
at ninety miles per hour or thereabouts show a total tractive
effort so low (even below ten pounds per ton in some
cases) as to leave very little room for atmospheric resist-
ance.
Perhaps the easiest way to appreciate the facts is to
calculate from the best attainable data the power required
to drive a given train at one hundred miles per hour. We
shall have to exterpolate with respect to some of our data,
but so short a distance as to involve very little uncer-
tainty.