The sun. [volume] (New York [N.Y.]) 1833-1916, 1903-07-26
TUNNELLINGLOWER BROADWAY
NEARLY All THE WORK WILL
BE DONE AT NIGHT.


GavatlOn VIII PrOceed--NOrk 10 Begin
I'm August ON Trinity Church Block.
The excavating work on the Broadway
section Of the underground railroad ex-
tension to Brooklyn will be begun in the
first week Of August Engineering diff
culties are anticipated because the subway
will he run near the foundations OF some
OF the largest and tallest buildings in the
city. Chief Engineer Parsons of the Rapid
Transit Commission says that the work
will be done without weakening the founda-
tions of any OF the skyscrapers.
The contract provides that the cont ractor
must maintain the surface of Broadway
In such a condition as will permit traffic
from 8 o'clock In the morning to Q o'clock
in the afternoon every day.
A. A. Brewster, the assistant engineer
who will he in charge of the work for the
Degnon-McLean Company, the sub-con-
tractors, said yesterday that on the lower
Broadway section there will have to be
encountered the hardest problems of any
on the route below Twenty-third street.
1t is possible that on the part Of the route
nearest the Battery the floor level Of the
tunnel will be below high-water mark and
caisson foundation may have to be con-
structed for the tracks. Under the contract
the work must be done in sub-sections of
$50 feet; one subsection may not be begun
until its predecessor ia completed.
The actual work will be begun on the
Trinity Church block just south Of Pine
street. Nearly all of the work will be done
at night. The beginning will be made
by sinking shaft. One Of the sidewalks
will have to be blocked in order to strip
the street surface. Except that the side
street will be open for vehicles and pedes-
TRANS all the time. As soon as the order
is given gang of men will begin to strip
the surface paving OF the designated block.
All the paving and earth removed will be
carted away and stored.
As soon as the paving is removed holes
will be dug for the reception OF uprights
to hold temporary beams, which will be laid
lengthwise with the street. Supported by
these uprights longitudinal beams will hold
cross planking to form new street surface
and the work OF excavation will go on
beneath. A shaft from the sidewalk will
give an outlet for excavated material. The
longitudinal beams-s-inch eye beams. it is
calculated, with a single support to each
thirty feet OF length, will bear all the weight
that can be put upon them by the regular
traffic. AS the excavation proceeds and
the radius or strain changes, room Will
be made for other supports. Each support
rests on solid earth foundation until a
second floor or surface is constructed below
1t and so on until the subway level Is reached.
A like process will sustain the railroad
tracks without in any way disturbing the
solidity Of their foundations
Instead of the foundation walls Of the
skyscrapers on lower Broadway being a
detriment the engineers calculate that they
will helm in the work of cOnBt rIctiOn by
have to sink for the removal of debris. A
sheeting of timbers on the roadway side
Of the sidewalks and those walls on the
building line will serve as the sides Of the
tunnel shaft.