If the grade of the ground is too steep to operate a track laid on it, one of the three methods may be adopted to obtain a grade for this track:
1. The steam shovel is made to cut a trench between the points A and B, Fig. 53, where the slope of the ground is too steep to permit operating a track laid on its surface, and varying in depth from 5 to 10 ft. as may be necessary to attain the desired grade. The excavated material is dumped at D, Fig. 54, to be removed with the next cut. The length of the crane will not permit dumping at E a sufficient distance (20 ft. or more) to obtain a berme and prevent the material washing back into the new cut in the course of time; it must, therefore, be dumped at D and removed as described, unless the slope of the ground is away from the cut, as indicated by the line D F, Fig. 54; in such a case the excavated material can be dumped at F.
2. By excavating the trench with teams and scrapers.
3. By through-cutting a trench with the steam shovel, loading the material on small dump cars or wagons, and wasting it at the nearest available place.
After the first loading track has been laid in this trench, the cuts are made as indicated in Fig. 54.
When the slope of the ground is too steep to permit a track to be laid on it which can be operated, or to cut a trench for it, as frequently occurs when the excavation passes through a high spur or knoll, Figs. 55, 56 and 57, the steam shovel mounted on standard gage railway tracks cannot be used, and a machine independent of a railway track for transportation must be employed. It is started at A, Figs. 56 and 57, loading small dump cars drawn by horses, and dumping at the nearest available place outside of the lines of the new cut, as at D, Figs. 56 and 57. Sometimes wagons are used if the cuts near the top are short and not very deep, so that a temporary standard gage track can soon be run through the cut, and the material loaded on cars. The dumping track at D is changed to E F, etc., Fig. 57, as the machine cuts lower, maintaining a descending grade from the steam shovel.
In cases of this kind it is often necessary to run the steam shovel up a very steep grade to reach the point where it is to begin work. This can readily be done by attaching one end of a one and a half inch rope to a strong tree and winding the other end around the driving axle. Then starting the running gear the machine can be drawn up grades where it could not otherwise propel itself. As a precautionary measure, it is advisable to use at least two ropes.