_East End._
_Deerfield Dam._--This structure is completed. Flashboards to be used in
low stages of water may have to be occasionally renewed.
The canal is finished as far as wheelpit No. 3. The machine-shop is
about 72 feet long, and 36 feet wide. It has three turbine wheels. A
fourth wheel is designed, but is not required at the present time, and
the pit to receive it is not completed.
In the basement of the machine-shop are two compressors. The first was
put in January, 1866. It has four cylinders 13 inches in diameter, and
20 inches stroke. This compressor is used to drive the drills, and
furnish air for the blacksmith shop. The second compressor was put in
some time in October. It has four cylinders 25 inches in diameter, and
24 inches stroke, and is used for ventilation one-fourth of the time,
two hours after each blast, viz., from 8 to 10, A. M., from 4 to 6, P.
M., and from 12 to 2, A. M. The compressors work satisfactorily. The
loss of power in the transmission of air from the machine-shop to the
drills, a distance of 4,500 feet, being hardly perceptible.
In addition to the compressors, there is in the machine-shop the
following machinery, viz.: three lathes, one of them worked by hand; a
drilling machine; a planer; a bolt-cutting machine and a saw-table.
Sixty horse-power is required to carry the machine-drills, the machines
in the shop, and to furnish air for the blacksmith shop. When the large
compressor is used, 75 additional horse-power is required. A circular
saw at the east end of the machine shop, is occasionally used, driven by
power derived from the turbine wheels.
The blacksmith shop, near the entrance of the tunnel, contains three
forges. The hand-drills are made, and, together with the machine drills,
sharpened at this shop. The ordinary repairs of the drilling machines
are done in the machine shop. New parts of the same are furnished from
Fitchburg.
The heading in the tunnel at this end when driven by hand was about 15
feet wide by 6 feet high. When driven by the machines it is 16 feet wide
and 8 feet high. Its location is in the centre of the tunnel, 4-1/2 feet
above subgrade, and 1-1/2 feet above the road bed.