=========================================+==========+==========+=======
|Manhattan.|Weehawken.| Total.
-----------------------------------------+----------+----------+-------
Duct feet | 115,962 | 35,155 |151,117
-----------------------------------------+----------+----------+-------
Average Cost per Duct Foot.
-----------------------------------------+----------+----------+-------
Labor | $0.035 | $0.032 | $0.034
Material | 0.043 | 0.052 | 0.045
-----------------------------------------+----------+----------+-------
Total field charges | 0.078 | 0.084 | 0.079
-----------------------------------------+----------+----------+-------
Chief office and plant depreciation | 0.005 | 0.008 | 0.006
-----------------------------------------+----------+----------+-------
Total average cost | $0.083 | $0.092 | $0.085
=========================================+==========+==========+=======
When the haulage was up grade, 6 by 6-in. Lidgerwood hoisting engines,
with 10-in. single friction drums, and driven by compressed air from the
high-pressure lines, were used. Down grade, cars were moved and
controlled by hand.
The muck which came through the shaft at Manhattan was dumped into
hopper bins on the surface and thence loaded into trucks at convenience.
At the open cut, the muck was dumped into trucks direct. The trucking
was sublet by the contractor to a sub-contractor, who provided trucks,
teams, and trimmers at the pier. At Weehawken, arrangements were made
with the Erie Railroad which undertook to take muck which was needed as
fill. The tunnel cars, therefore, were dumped directly on flat cars
which were brought up to a roughly made platform near the shaft.
The hoisting at Manhattan was by derrick at Tenth Avenue and the open
cut, and by the elevator at the Manhattan Shaft. At Weehawken, all
hoisting was done by the elevator in the shaft.
The sand and stone were received at the wharves by scows. At Manhattan,
these materials were unloaded on trucks by an overhead traveler, and
teamed to the shaft, where they were unloaded by derricks into the bins.
At Weehawken, they were unloaded by an orange-peel grab bucket, loaded
into cars on the overhead trestle, transported in these to the top of
the shaft, and discharged into the bins.
The cement at Manhattan was trucked from the Company's warehouse, at
Eleventh Avenue and 38th Street, to the shaft, where it was put into a
supplementary storage shed at the top of the shaft, whence it was
removed to the mixer by the elevator when needed. At Weehawken, it was
taken on flat cars directly from the warehouse to the mixer.
Lighting.
Temporarily and for a short time at the start, kerosene flares were used
for light until replaced by electric lights, the current for which was
furnished by the contractor's generators, which have been described
under the head of "Power Plant."
The lamps used along the track were of 16 c.p., and were protected by
wire screens; these were single, but, wherever work was going on, groups
of four or five, provided with reflectors, were used.
Pumping.
Two pumps were installed at the Manhattan Shaft. They had to handle the
water, not only from the rock tunnels, but also from those under the
river. One was a Deane compound duplex pump, having a capacity of 500
gal. per min., the other, a Blake pump, of 150 gal. per min. They were
first driven by steam direct from the power-house, but compressed
air was used later. When the power-house was shut down, an
electrically-driven centrifugal pump was used. This was driven by a
General Electric shunt-wound motor, Type C-07½, with a speed of 1,250
rev. per min. at 250 volts and 37.5 amperes (10 h.p.) when open, and
22.9 amperes (6 h.p.) when closed, and had a capacity of 450 gal. per
min. To send the water to the shaft sump during the construction, small
compressed-air Cameron pumps, of about 140 gal. per min., were used.
At the Weehawken shaft two pumps were used; these dealt with the water
from the Bergen Hill Tunnels as well as that from the Weehawken Tunnels.
At first a Worthington duplex pump having a capacity of about 500 gal.
per min. was used. Later, this was replaced by a General Electric
shunt-wound motor, Type O-15, with a speed of 925 rev. per min. at 230
volts and 74 amperes (20 h.p.) when open, and 38.5 amperes (10 h.p.)
when closed. Its capacity was 240 gal. per min. During the progress of
the construction, the water was pumped from the working face to the
shaft by small Cameron pumps similar to those used at Manhattan. When
the work was finished, a subgrade reversed-grade drain carried the
water to the shaft sump by gravity.
The work in the Manhattan Land Tunnels was practically finished by May
1st, 1908, though the ventilating arrangements and overhead platform in
the intercepting arch were not put in until after the River Tunnel
concrete was completed, so that the work was not finished until
September, 1909.
The Weehawken Land Tunnels work was finished in July, 1907, but the
benches and ventilating arrangements in the Weehawken Shaft were not put
in until after the completion of the Bergen Hill Tunnels, and so were
not finished until August, 1909.
The reinforced concrete wall around the Weehawken Shaft, together with
the stairs from the bench level of the shaft to the surface, was let as
a separate contract; the work was started on September 15th, 1909, and
finished by the end of December, 1909.