Omaha daily bee., 1903-03-15

have no business in q caisson, but the best
OF men in the best Of condition are often
times overtaken. 1t is paralysis that kills
them. A man stricken with caisson-
paralysis never RECEIVERS. Another Afiic-
ton, which seldom is fatal, is caisson-
fever, or what the men call tho bends
This causes them to become perfectly limp
and helpless. In either case the trouble Is
caused by noncirculation OF the blood and
In paralysis by the bursting OF blood ves-
sells"
There is always n lot OF water in the
caisson chamber and the men slOp about
In high boots, and when they come out they
need the clean clothing and a chance 10
wash that which they take of In the trough
OF warm water that is provided. Their work
is lighted by electric bulbs and they are
made as comfortable as possible. At pres
ent thirty men are working in the caisson
in the center of the river. They labor in
equal squads in three-hour shifts.
AS they go deeper the hours Of work
will be lessened, accordingly as the air
pressure increases. They are paid $3.50 n
day for the work at present. When they
were down seventy feet in the old caisson
they were getting SO a day for four hours
WIN WV " a. - ~ bOIuV
places it has been necessary to pay enor-
nous wages to induce men to work in the
caissons, but there have been plenty Of
laborers willing to risk their lives for little
more than ordinary pay 80 far at Omaha
Most Of the caisson men make a business
OF IL and none belongs to this city.
When they have completed their work
the ingress cylinder will be filled up tight
with concrete and the cofferdam founda-
ton will be ready for the sandstone ma
sonry in ponderOus blocks above. 1t is a
fact not generally known that these sec
tions Of stone are carefully numbered and
cut, each to I'LL a separate niche In the
design of the whole pier. The blocks range
from two to three and one-half feet in
thickness, and are from three to Ave feet
long, weighing several tons apiece. Each
has been cut carefully and a place marked
for 1t in the plan. The masonry above
the water is not solid sandstone. Only the
outer walls are of this material, and this
is to resist the disintegrating action Of tho
elements. Inside the inevitable concrete
is resorted to, the whole being welded to-
gether by 1t. The men who are putting
in the superstructure for the new bridge
say that 1t will last forever, even the
hard pine sheathing of the cofferdam never
rotting as long as 1t is covered by water,
or is in the ground under the water.
For the pivots an entirely different
method Of inserting the piers is to be
employed. The huge steel cylinders. tho
outer one forty feet in diameter and tho
inner twenty feet through. will be built at
the waters edge. The two are united by
a conical diaphgram at the bottom. They
will be braced by steel struts and the
space between the inner and outer cylin-
Aarg vrgII h. AHA "a -. 4
as built. There is a cutting edge at the
bottom, and with the weight on top, which
will be immense, the thing will sink, as
big dredges scoop out the river bed in
the center. In case additional excavating
powers should be required, the hydraulic
system will be used, provision being made
for a series OF water jets around the
cutting edge. The present pivot pier was
sunk in this way. There is no chance
for loss OF life and the method is quick
and satisfactory. The big cylinders will go
down 120 feet below the water when 1t IL
at low mark, and will contain approx
mately II, 900 tons OF metal, valued at
about S35, 900. On this will go the slightly
blocks OF sandstone and the concrete FILL
ing.
Sixty-hOrse power electric motors, maxi
ing $50 revolutions per minute, will operate