\fdO'^ - Old Forge Coal Mines

RAILROAD CONSTRUCTION.
(813)
(814)
See Art. 1454.
See Art. 1455.
(QUESTIONS 8:i3-«72 )
(815) The slope given to embankment is 1^ horizontal
to 1 vertical, and the slope usually given to cuttings is
1 horizontal to 1 vertical. (See Art. 1457 and Figs. 380
and 381.)
(816) The height of the instrument being 127.4 feet
and the elevation of the grade 140 feet, the instrument is
below grade to an amount equal to the difference between
140 and 127.4 feet, which is 12.6 feet. The rod reading for
the right slope being 9.2 feet, the surface of the ground is
9.2 feet below the instrument, which we have already shown
to be 12.6 feet below grade. Hence, the distance which the
surface of the ground is below grade is the sum of 12.6 and
9.2 which is 21.8 feet, which we describe as a fill of 21.8
feet. Ans. The side distance, i. e., the distance at which we
must place the slope stake from the center line, is 1^ times
21.8 feet, the amount of the fill, plus \ the width of the
3 X 21 8
roadway, or 8 feet. Therefore, side distance '
=
-{-8 =
A
40.7 feet. Ans.
(817) The height of instrument H. I. being 96.4 feet,
and the rod reading at the surface of the ground 4.7 feet,
the elevation of the surface of the ground is 96.4 — 4.7 =
91.7 feet. As the elevation of grade is 78.0 feet, the amount
of cutting is the difference between 91.7 and 78.0 = 13.7
feet. Ans.