Wood County reporter. [volume] (Grand Rapids [i.e. Wisconsin Rapids], Wis.) 1857-1923, 1883-06-07

Iouuuaelous LOT Ine Two huge stone
towers on which the bridge was to swing.
1t was necessary of course, to rest the
foundation on bed rock, and to do this
1t was required liz Brooklyn to exca-
vate to depth of forty-five feet below
the water line, and in New York to a
depth OF seventy-eight feet. Of course.
ordinary methods of evcavating were
impossible, as it was necessary to excs-
vate the bed OF the river. To do this
the water at the bottom of the river Is
driven out from under vessel or Gals
son OF the size of the contem plated
foundation by means of compressed
air, thus enabling the men to work, as
ltiwere, in large diving. bell. Tnese
great inverted boxes were made of
tough southern pine, fastened by bolts
and Joists. O: top of each caisson the
huge foundation was built by a scien-
tlic laying of massive granite blocks
whose weight gradually sunk the Gals
son to Its resting place on the bottom
OF the river. When the work had reach
ed this stage the water in each caisson
was pumped out, compressed air being
turned in at the same time to keep
were admitted inside the caissOn to dig
out the bottom of the river, the soil
being taken out of the caisson as the
work progressed. The work of exca "a
ton and masonry on top of the caisson
kept sinking it until solid foundation
was reached, and then each caisson
was filled with solid masonry and con-
crete, and the foundations. after wears
work, were completed. Never before
were piers built of such vast dimen-
slOns and with more care and caution
than these two monuments of Ameri-.
can skill. Now, after the entire weight
Is placed upon them, the total settle
ment has been no more than what is
due to the natural shrinkage of the ma
terlal-about one inch from the time of
reaching high water.
Ga these good foundations the towers
were built They are mainly of granite,
but there Is some limestone in them.
There are probably, ever, thing con-
sidered, the finest specimens Of stone
building In the world. The interior
stones wer@ all laid In level courses and
squar> d. Only 8 per cent. of the bulk
joints, which were carefully filed with
concrete. At important points all stones
were tied with iron cramps. The overs
are 2768 feet Ugh. At the height of lis
feet above high-water mark each tower
Is di, ided into three sub towers by two
avenues 81 feet wide. These rise to s.
height of 1903 feet, above which the
full towers rise so feet higher to point
where huge iron plates rest as kind of
saddle for the play of the cables sup
porting the bridge and running back 10
toe anchorage 'on either side. Tue
Brooklyn tower was finished in Nav,
1875. and the New York tower in July,
1876. The masonry in the towers
measures UP to the enormous amount
of $4,000 cubic yards, and that in the
anchorage to 66 600 cubic yards.
THE BRIDGE
may be said to begin at Chatha "a
square in New York and end at tie
corner of Sands and Washington streets
IN Brooklyn, but the bridge proper, the
single span which stretches FROM tower
10 tower, is 5954 feet between the
towers, and 3 46O feet from anchorage
to anchorage At the towers the bridge
Is lis feet above high water mark, and
in the center 135 feet. Clearly the first
thing to be done before stretching q
wire across was the establishment Of
an anchorage on each side of the river
These apchorsges hold the wires, and
are located $50 feet inland from the
towers on each side. They stand, vast
aggregations Of stone, 119 feet by 1872
feet at the base, and weighing 60 600
tons each. Al the bottom are four huge
cast-iron rlates, one for each cable, 164
feet by III feet in size, q feet thick,
and weighing 46 900 pounds each. In
this cast iron anchor plate are fastened
parallel iron bars, which run up through
the solid masonry and through the face
of the anchorage walls some twenty
the cable. The bridge is held up by
cables-four huge punches of wires,
laid parallel and bound together by an
unbrOken wrapping, also of wire. Each
wire is an eight of an inch thick, and,
as there are 5000 of them in each
cable, making bunch or bundle about
sixteen inches thick, the physical diff
Guilty Of binding them together mey be
imag ned. To do this it was Necessary
TO arrange tie wires in small parcels.
,l9 to q cable, and each holding 278
single wires. These parcels or bundles
formed 3 c0ntiauous wire rope 200
miles long, which was carried from
anchorage to anchorage, back and forth,
278 times. The ropes when laid were
bound together, and then the several
ropes were tightly wound into one huge
cable. In this way four cables were
made.
1t was no easy task to send the arst
wire rope across from tower to tower.
1t was first coiled on a scow. One end
was raised to the tower top, dropped on
the other side, taken back to the an
chorage, and made fast. The scow was
then towed across the river, the wire
rope running from the coil as 1t went.
Once there it was hoisted to the top of
the second tower, and in turn fastened
at the anchorage. when second rope
moo ID tho