Iowa County democrat. [volume] (Mineral Point, Wis.) 1877-1938, 1883-06-01

O6lnE taken OUT OF the c&lSSO0 as tl6
work progressed. The work of exca "a
ton and masonry Oh tep of the caissou
kept sinking it until solid foundation
was reached, and then each caisson
was filed with solid masonry and con-
crete, and the foundations, after years
work, were completed Never before
were piers built of such vast dimen-
siops and with more care and caution
than these two monume ents 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 tine ma
teriar-about one inch from the time of
reaching high water.
Ga these good foundations the towers
were built. They are msinlF 7 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
squsr d. Ouly per cent of the bulk
of the towers was taken up by the
joints, which were carefully filed with
con rete. At Atimportantp points ali stones
were tied with iron cramps. The w RS
are 276a fest Ugh. At the height Cf 115
feet aoove high-water mark each tower
is di ided into three sub towers by two
avenues 81 feet wide. These rise to q
height OF 1903 feet, ab.ve which the
| full towers rise so feet higher 10 a point
where huge iron plates rest as kind of
q saddle for the play Of the cables sup
porting the bridge and running back to
tne anchorage 'on either side. Tue
Brooklyn tower was finished in May,
1875, and the New York tower in July,
1876. The masonry in tho towers
measures UP to the enormous amount
of So 900 cubic yards, and that ia the
anchorage to &C 900 cubic yards.
THE BRIDGE
may be said to begin at Chatha4a n
| square il New York and end at e
corner of Sands and Washington streets
in Brooklyn, but the bridge proper, the
single span which stretches from tower
TO tower, is | 5953 feet between the
towers, and 3 46O feet from anchorage
to anchorage At tbs 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 a
wire across was the establishment of |
an anchorage on each side of the river. |
these auchoragPs hold the wires, and |
| are located $50 feet inland from the !
towers on each side. They stand, vast
aggregations of sto-e, 119 feet hv 1872 |
feet at the base, and weighing 60 900 |
tons each. At the bottom are four huge |
ctst-iron rlates, one for each cable, 161 |
feet by III feet in size, q feet thick, |
I'D if 0nn T..
this cast,lron anchor plate are fastened |
parallel iron bars, which run up through |
the solid masonry and through tie face |
of the anchorage walls some TIVE -nty |
five feet, where they meet the end of |
the cable. The bridge is held up by |
cables-four huge bunches of wires, |
laid parall>. and bound together by an |
unbr0ken wrapping, also If wire. Each |
wire is an eight of an inch thick, and, |
as there are 5000 OF them in each |
cable, making bunch or bundle abont |
sixteen inches thick, the physical diff
Guilty Of binding them together mey be |
imag ned. To do this it was necessary
to arrange t. wires in small parcels. |
- to cable, and each holding 27S |
single wires. These parcels or bundles
formed 8 continuous wire rope 200 |
miles long, which was carried from |
anchorage to anchorage, back and forth,
2I0 times. The ropes when laid We're |
bound together, and then the several
ropes were tightly wound into one huge |
cable. In this way four cables were
made.
1t Has no easy task to send the first |
wire rope across from tower to tower |
1t was first coiled on scow. One end |
was raised to the tower top, dropped on
the other side, taken back to the an
chorage, aud made fast. The Sow was |
then towed across the liver, 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 a second rope |
was carried over In the same way the |
two were Joined over windlass, and |
an endless wire rope or belt was then |
workable through the entire distance,
by means OF which the rest of the wires |
were pulled across from tower to tower |
After the first wire ropes were success
fully carried the experimental part was
over; the rest was simply q matter OF !
routine and careful duty. They began |
to run and regulate the cable wires in |
June, 1877, and flushed the work in
October, 1873. The wire is of steel, and |
Its manufacture was carefully inspected. |
The cable making was done probably |
with more care than ever before, in or
der to obtain perfectly uniform strain |
throughout. To guard against cOrro-
sion, each wire was galvanized with ENC |
and coated with oil, and the cables were |
painted with white lead.
Toe roadway is So feet wide. SIX
trusses extend along the entire bridge, |
giving it increased strength and stiff |
ness, and dividing it into five sections.
The two outer ones are each sufficiently |
wide TO allow for two lines of vehicles |
The next two are reserved for cars, and |
the center section Is the footHay. The |
latter measures 10 feet seven inches In |
! ), 18th, and is elevated so that an unob- |
structed view is obtained, while tele-
graph wires and pipes for various pur
poses occupy the space beneath. The
Cars are TO run across the bridge on the
principle recently applied to the trao-
tlon of city passenger cars in Chicago
and Pnlladel lphia-namely, that of at
tachlng them at will to 4 continuously
moving wire rope. The speed of this
rope will be maintained at about ten
miles an hour. 1t is intended to run
cars at intervals OF one to two minutes
Tne estimated time of crossing the
bridge on the cars Is FIVE minutes. The
open spaces in the anchorages and
under the many arches of the ap.
proaches leading to them will be utilized
as warehouses. Tue distance between
the termini is 8, ,9s9 feet. The approach
es fIou the street level to the anchor
ages are built Of masonry, and the
grade is comparatively eight, being.only
st feet in 1U0 feet, or somewhat less
than that on Wall street between
Broadway and Nassau street. At each |
erminus Is large and rnsnental de-
cot. built of iron, through which the
foot passengers get access to the bridge, |
and in which the cars will receive and
discharge their passengers. The toll |
| for foot passengers will he one cent. |
For the present, cent fares will be |
charged in the cars, except during GER
tain hours of the night and morning,
when the fare will be cents.
The weight of the central span IS
6 40 tons, and the estimated weight of |
q crowded bridge, carts, people and |
| all Is $50 tons. These suuportiup ca