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After a side cut about 20 ft. deep had been made, the side holes were drilled 20 ft. deep, and the holes were loaded and tamped for the full 20-ft. cut. Under the terms of the specifications, the contractor was required to complete the excavation on the sides by drilling broaching holes.
It was found that a derrick operating at the top of a 20-ft. cut would handle about 40 cu. yd. per shift, whereas, if operating at the bottom of the cut, it would handle about 60 cu. yd. per shift. The elevator derricks at Tenth Avenue were very efficient, and each could take care of the material from four derricks at the bottom, hoisting 250 cu. yd. per shift a height of 60 ft.
They were formed by drilling a 20-ft. hole and exploding at the bottom of it, without tamping, two or three sticks of dynamite, and repeating this process with heavier charges until there had been formed at the bottom of the hole a large cavity which would hold from 100 to 200 lb. of dynamite.
The decision made, I walked through the blizzard with Worsley and Wild to examine the 'James Caird'. The 20-ft. boat had never looked big; she appeared to have shrunk in some mysterious way when I viewed her in the light of our new undertaking.
In the early morning of April 1 we listened again for the wireless signals from Port Stanley. The crew had lashed three 20-ft. rickers to the mast-heads in order to increase the spread of our aerials, but still we failed to hear anything. The rickers had to come down subsequently, since we found that the gear could not carry the accumulating weight of rime.
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