The sun. [volume] (New York [N.Y.]) 1833-1916, 1915-09-26

had to take conditions as he found
them. A populous section of the
Bronx had to ne traversed. and of
curse at a height nat could not in
terfere with street traffic. A bascule
left bridge had to be provided for the
Bronx Kill, which will be deepened
by the Government for navigation;
another type OF bridge for Little Hell
Gate. and steadily rising piers in be-
tween that would insure an elevation
at the Fast River sufficient to give a
clearance above mean tide of quite
1876 feet. Physical conditions were
anything but favorable to low cost
of construction; and it is safe to say
that this connecting line, In all ten
miles long, represents economy at "A
prospective total outlay of $50, 600, 900.
OF course the major part of this sun
is involved in the building of the He'll
Gate span.
There were two places in approach
ing the Fast River from the north
where we encountered difficulties. AT
the Bronx Kill we found troublesome
subsurfaCe conditions that obliged us
to go down from ninety to ninety-fve
feet in order To get a stable foundation
for the supporting piers. and the ma
ture OF the soil was such that the
caisson workers had to labor under
pretty high pressure. Again. when
we came to the western bank of the
East River II was necessary to bur
row beneath the surface to depths
ranging from nfty-eight to 40 feet
| to reach the rock and to get q firm
footing there.
Under the bridge tower on Wards
Island Sc used t~wenty-one' great con-
crete caissons. Some of them were
cylindrical and eighteen feet in diane
ter. while others were rectangular.
with dimensions Of 30 by 10 feet. These
We're much larger than the caissons
required for the building Of any Of
New NorL's skvscrapers and went
deeper too.
I'm order to SIM these
We months of work was required.
because during the operations "A very
troublesome assure was encountered
which ran d|iaconally across the foun-
cation space chosen for the western
tower of the Hell Gate span. We had
to max. absolutely sure of the rigid
ity of the footing. for the thrust from
the enormous load of the arch would
have 20 he borne 10y the foundation.
Ne could not risk ANY subsrquen;
settlement. This particular arch. the
longest and heaviest Of it's kind. is
designed to sustain four tracks. two
for passenger and two for freight
trains. ami must he equal To the max
imum burden such service might i'm
pose.
The upper and lower curved mem
hers uf the arch aIe technically known
~ chords. and the lower one is by
far the Yet, as you look
al these members from midstream
they seem comparatively light until
YOU catch sight Of "A moving work
man, appearing about the size of an
ant. and then ones sense of proper
ton is aroused. The bottom chord
IL hoXliEe in cross section and is big
gost where il rises from its slanting
foundation of stone at the base Of the
other tower. At thai point il is about
ny feet deep. up and down, and :
feet across between its thanking YER
lltsl N'illN u llll'N ia NV INV
, die there is a dividing bulkhead or
diaphragm. and from time 10 time
men must travel from end 10 end of
each member OF the chord for the
purpose Of painting the inner sur
faces and watching for the least sign
Of corrosion or deterioration. AT its
highest point. or crown. each OF the
two lower chord members will have
a vertical and n horizontal dimension
OF nearly : feet.
Put figures of this sort don't tell
the whole story Of the M ~ssiveness by
any means. Section by section the
two lower chord members have been
raised into place and Joined, and the
frs, unit section of each weighed
when pinned to its ponderous hinge
n matter of 1875 tons This was in
!, dependent of the connecting vertical