railroads have been built, and aside from extensions and relocations, this kind of work is no
longer a major concern. Your endeavors, then, should be directed not toward learning how to
locate a railroad but rather toward an understanding of construction elements and why railroads
were built as they were. Only then will you have a proper appreciation of a sound program of
maintenance.
a. Path of the railroad. Plane geometry teaches that a straight line is the shortest
distance between two points. For the distances traversed by railroads from one city or station to
another, the surface of the earth can be satisfactorily simulated by a plane. Obviously, then, the
most desirable path for a railroad is a straight line. However, the limitations mentioned earlier,
arising from smooth rails and wheels, coupled with the irregularities of the earth's surface,
generally prohibit such a route. If a railroad line were laid straight from one city to another, such
a line would usually involve grades of such steepness that trains, as we know them, could not
pass over it.
Once it was believed that smooth-wheeled trains operating on smooth tracks
could climb only the lightest grades. This erroneous opinion resulted in the use of rack railways
and inclined planes.
(1) Rack railways. To eliminate the slippage of a locomotive's driving wheels on
steep grades, a rack (rack rail) was placed between the rails. This rack in turn meshed with a
gear wheel or pinion of the locomotive. A locomotive so equipped was also referred to as a
cogwheel locomotive.
(2) Inclined planes. To overcome steep slopes, engineers built inclined planes
requiring stationary engines at the top of each grade. Trains traveled over level tracks as far as
possible and were then pulled up extremely steep grades by cables attached to the stationary
engines. Afterward the trains proceeded to the next incline where they were either let down or
pulled up the succeeding hill. This operation may be compared to that of a canal and locks, the
planes corresponding roughly to the locks.
In a few places, inclined planes are in use today. Notable are the triple Ashley
planes of the Jersey Central at Wilkes-Barre, Pennsylvania. But for the most part, they have long
been gone from the railroad scene.
b. The "George Washington." In 1836, one of the important events in railroad
history took place. The locomotive "George Washington' climbed the Belmont plane at
Philadelphia hauling a
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