The retaining-wall plant was identical with that described for the first period, with the addition of two Ransome 1-cu. yd., concrete mixers, with vertical engines mounted on the same frame, using compressed air.
3.—Pit-Excavating Plant.
The pit-excavating plant included that listed for the first period and, in addition, the following:
One Vulcan, 30-ton, steam shovel, with 1-cu. yd. dipper and a vertical boiler.
One Ohio, 30-ton, steam shovel, with 1-cu. yd. dipper and a vertical boiler.
Four guy derricks (50 to 80-ft. masts and 45 to 60-ft. booms), operated by Lambert 7 by 10-in. engines, with two drums and swinging gear, mounted with 25-h.p. vertical boilers, but driven by compressed air.
Seventy Ingersoll-Rand rock drills, Nos. 1, 3¼, and 4.
Two Rand quarry bars, cutting 10 ft. in length at one set-up, and mounted with No. 4 drill using a Z-bit.
4.—Transportation Plant.
Twenty-one H. K. Porter locomotives, 10 by 16-in., and 36-in. gauge.