The Pulaski citizen. [volume] (Pulaski, Tenn.) 1866-current, 1873-11-20

4
last tor an unlimited time, and are uset
for the foundations of brick and stone
edifces; and the practice of docking
timber, by immersing it for some timG
in sea water, after it has been seasoned
is generally admitted to promote its du.
rability. There are some experiments
which appear to show that, after the dry
rot has commenced, immersion in salt
water effectual1y checks It's progress and
preserve the remainder of the timber.
If care be taken to renew the coat of
paint as often as it decays, wood on the
outside of the buildings may be made
to last for centuries paint, however, is
no preservative against the internal or
dry rot, notwithstanding the opinion so
generally prevalent to the contrary.
THE INTERNATIONAL BRIDGE.
Completion OF the Great work across the
Niagara river, Connecting the United
States with Canada.
The great international bridge across
Niagara river from Buffalo to Fort
Erie, In Canada, has been completed,
although it has not yet been formally
thrown open to travel. Of the work
the Buffalo Commercial Advertiser fur
nishes a complete account, from which
we quote the following interesting de-
scription
To state the fact roughly but plainly,
the entire length of the bridge is about
three-quarters of a mile. But more in
detail the length is as follows In the
main river, 1900 feet; over Squaw is
land, 1900 feet Ctrestle work., and over
Black Rock harbor, $50 feet. The en-
tire length of the superstructure in the
main river is ], $3.50 feet; in Black Rock
harbor, 40 feet. There are nine spans
in the portion on the main river and
three in the Black Rock harbor four
of 100 feet in the clear, and three of
24O in the clear. Over the main river
also are two draw openings of 100 feet
each total length of draw girder, 362
feet. In Black Rock harbor are two
draw openings of 80 feet each, and one
fixed span 900 feet in length. In the
main river are eight piers and two abut-
ments and In the harbor two piers and
two abutments. The abutments are 40
feet long by 80 wide, at the bridge-seat
level. Over the bridge is laid a track
for railroads, and a common sidewalk
for foot passengers. The piers and
abutments are built of sandstone from
Georgetown and Acton, Canada, and
Berea, near Cleveland, Ohio. The iron
of the superstructuro was from the
Phenixville Iron company's works.
Phenixville, Penn. The first caisson
was launched on the 18th of July, 1870,
and the work progressed steadily up to
the time of completion. 1t must be re-
membered that the current of the river,
at the point where the bridge is loca-
ted, runs from five miles and a half to
ten miles an hour, according to the state
of the wind. This was throughout one
of the greatest difficulties encountered,
and frequently retarded progress.
Then, too, the depth of water varies
from twelve to forty-fve feet. The
ice in winter, some may think, would
damage the bridge in course of time,
but the ice-breakers afforded ample pro-
lection, and cut to pieces blue ice two
feet thick with comparative ease. Au-
other remarkable thing connected with
the history of the bridge is that during
the whole course of the work not sim
gle life has been lost. The workmen
have, many of them, often been exposed
to dangers. but always have escaped.
The respective weights ofthe different
spans over the river are as follows 100
feet, 130 tons; 24O feet2O8 tons; 362 feet
draw, 353 tons and the quantity
of iron used in the whole bridge
amounts to upward of 1000 tons. At
the request of Capt. Tyler, the English
government inspector of railways, who
visited the bridge in November, 1871,
on behalf of the English shareholders,
one of the spans of 100 feet was loaded
with 210 tons of iron rails, equally dis
tributed over the floor beams "a weight
greater than that of a continuous train
of locomotives covering the SPAN, and
left in that condition for three DAYS.
The test was highly satisfactory, the de-
Election being found to be only about
one inch, and the truss returning ex-
actly to its former condition on the re-
moval of the rails.
The bridge has been leased to the vari.
GUS roads whish will cross it for twenty
years. The roads are the Crank Trunk,
the Great Western, the Canada South
ern, the New York Central, the Erie,
and the New York West Shore and Chi
cago. Most of these railroads have al
ready constructed their approaches to
the bridge, and will commence sending
trains across at as early day as posi-
BILE. The original plan contemplated
carriage-way, but this was abandoned
for the reason that, as the bridge was
three-quarters of a mile long, and so
many trains were to cross It, there would
very seldom be a chance for carriages
to cross without interfering with the
trains.
The entire cost of the bridge, in
round numbers, is not less than g, ,5OO,-
COO. OF its practical benefits we leave
the reader to Judge, merely stating in
conclusion that it supplies a want long
felt by the different railroads which have
for 50 many years been obliged TO cross
the Niagara river on the steamer Inter
national.