The two West Shafts were located in the streets and
were supplied with short timber trestles similar to those at the
Intermediate Shafts. One telpher was taken from each of the Intermediate
Shafts to operate at each of the West Shafts. In addition, a number of
stiff-leg derricks were set up along the open-cut section, and were
operated by Lidgerwood or Lambert air hoisting engines, or by electric
motors, as circumstances dictated. A 15-ton Bay City locomotive crane
was also used along part of the open-cut work on 32d Street.
Several concrete plants were installed at points along the open-cut
section, and were moved from place to place, the same general
arrangement being adopted as at the plants already described. No. 3 and
No. 4 Ransome mixers were used, and were generally set up at about the
level of the top of the arch. The sand and stone storage bins were made
of scantlings spiked together, and were necessarily rather shallow on
account of the proximity of the tunnels to the street surface.
_Thirty-fifth Street Pier._--For the receipt and disposal of materials
at the 35th Street pier, four stiff-leg derricks, operated by electric
hoisting engines, were installed. Two were used in lifting the muck
buckets from the wagons and dumping their contents on the scows for
final disposal (Fig.
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