The Superior times. [volume] (Superior, Wis.) 1870-1912, 1885-02-28

published an article descriptive OF the
new railroad bridge across the st Louis
bay. We take from the article the
following points of general interest:
THE CONSTRUCTION.
The curves in the bridge were made
in order to cross the channel at right
angles, saving considerable expense in
The building of the span near the draw.
Ia the first place pilling has been
driven with four in each bent, four
feet apart, and to make them solid 1t
has been necessary 10 put some of them
down forty feet below the water The I.
piles are about II inches in diamete'
at the lower end and IS inches at the .
top. After the piles are driven and
squared at the top, cap 12x12 and /
Is feet long will be placed upon them +
and bolted fast with 1x25 drift bolts. I
Two sway braces 4x10 and Is feet /
long running in a horizontal direction,
besides 2 sway braces 4Xl0 and p feet T.
long RAINING diagonally are firmly /
bolted oil the piliug to strengthen the
bents. From one to another of these
bents, 10 feet, are placed four string
ers 9x16, Is feet long and on one side
one stringer 6x6, Is feet long. On
this framework will be placed the ties
and iron. On the side of the bridge
is to be built foot walk Of two inch
plank, 40 inches wide and guarded on
/ the outside by a railing.
THE DRAW.
The draw is located $50 feet from
the Minnesota shore, ana will lee 246
feet long, giving 100 feet clear water
wav on each side. 1t is to be built of
wrought iron and rests in the center
on 4 round stone pier, q feet in diam
eter at the top, and ut the ends two
piers, s feet bread and % feet long
These piers are built Of Mankate lime
stone, except the center pier which IS
surmounted with top of st. Cloud
dressed granite. The lower and upper
tiers of stone are deweled together
with fine bowels in each stone making
it impossible for them to slip from
their places. The first step in build
ing these piers is to drive pilling and
cut them off below the surface of the
water. Then a grillage, made Of
square timber, is placed upon this,
and upon the latter is laid the stone,
which sinks down to solid level The
central pier rests upon 100 piles cut
oil 16l feet below the surface Of the
water and the grilIages are 32x32 feet
ana II feet high. The others are
13x33 feet and II and II feet high,
on 10 piles each On the side Of the
draw iarlhest from shore Is one span
153 feet long, of wood and iron com
biuvd. The timber il contains IS from
saw mill in northern Wisconsin and
Is said to be some Of the finest ever
used. The outer end Of this span rests
ga 4 pier similar 10 those at each end
of the draw. The space IS high enough
to permit the passage d tugs without
opening the draw, which will need TO
be opened only en- the approach OF
; large vessels.
PROGRESS OF THE WORK.
On account Of the cold weather
werI, could not be pushed as fast as
the contractors wished; nevertheless
the men have worked whenever pos
: sibIe and have been out on the bay
: when the mercury stood from 26 to q
E below zero. The work was to have
been completed February ], but the
:" stone work could not be commenced
as soon as desired and the whole
d structure will probably be finished b,
e the middle Of March.
II THE MAGNITUDE OF TIE WORK
Is something remarkable for pill
n bridge and there are few larger one
Is in the Northwest. 1t is 500 fee
4 from shore to shore, or a little NOR
Is than a mile, and the approaches a
each end 400 feet long. The high
' averages about seventeen feet abov
+ water. The timber used amounts t
4 almost at 100000 feet, board mea:
'. ure, and there are about $50 yard c
4 stone used in the construction of til
', piers. There are about 10 men a
ID work and twelve teams, besides tn
IN engineer corps. -Four steam pile driy
er ers are kept at work most Of the time
re The handling Of stone at the piers
done by a steam derrick.