Fig. 42.
After the first cut has been completed, the pit track, A 1, [Fig. 36], becomes the temporary main and loading track; the main track is taken up from C to H, and the steam shovel run back to C to begin the second cut, [Fig. 42], excavating it in the same way as the first, and loading on the temporary main track. This track again is taken up after the second cut, the machine begins at D and ends at G for the third cut and loads on the pit track in the second cut; the fourth cut is made in a similar way, the machine beginning at E and ending at F, [Fig. 36]. The fifth and last cut is merely a widening cut, made by loading on the track in the pit of the fourth cut. The material of each cut after the first is loaded on the track laid in the preceding cut. After the completion of the last cut, the permanent subgrade having been reached, the main track is laid on the permanent line, and the small quantity of material obtained from cutting the ditches loaded on cars by hand and taken away for unloading. The most frequent depth of cut made at the summit of grades is about 10 ft. (two cuts), [Figs. 38] and [39].
Fig. 42½.
Fig. 43.
