The Billings gazette. [volume] (Billings, Mont.) 1896-1919, 1902-08-08
KEEPS WATER OUT OF MINE.
New Process Used in. Sinking Shaft
In England.

-L TH .EEE
Following is the Scientific Alneri-
cans illustration of an English game
OF f%reezeput that might be used to adj.
tage in the sinking of mine shafts in
parts Of this country where there is
quicksand with which to contend.
An interesting experiment with the
freezing system of shaft sinking is
being carried out at the Washington
colliery in the north of England. This
process, the patent Of Messrs. Gebhart
4 koenig -cf Nordhausen, has been
found indispensable for sinking a
shaft where the peculiar conditions Of
the soil, such as sand or sliding clay.
prevent the shaft being sunk in the
ordinary way. At this Washington
colliery, when operations were com
menced for sinking the shaft, it was
discovered after the surface earth had
been removed, that the next geologi-
cal stratum consisted Of wet and
quick" sand. Had attempts been
made to bore the shaft through such
a stratum as this by conventional
means, the water would have pene.
trated into the hole, and the sides
would have fallen in, endangering the
lives of the artisans below. Also, if
pumping had been tried, the pumps
would have brought away sand as we'll
as water, and thus have caused a still
greater collapse. The bed of sand is
80 feet in thickness, and is followed by
80 feet of bcwlder clay.
The freezing process consists in
freezing the sand around the shaft
ring until 1t becomes perfectly solid.
When the site of the Shaft was decid-
ed upon. a ring pierced with % holes
was bored in the ground, the diameter
Of the ring being 22k feet. Into each
OF these holes an iron pipe was plac-
ed, having within it a copper tube.
with a perforated bottom. A freezing
mixture comprising brine of chloride
of magnesium 26 per cent, cooled by
means of the liquefaction of ammonia.
"so AuAA w CA4O NOppCl CuOCS, pdSS0u
through the perforated bottoms into
the iron tubes-which we're closed
at the ends-and passed back to the
tanks, So that a constant circulation
was kept up. The temperature of the
brine was 20 degrees below zero, and
had the effect of freezing the
ground around the pipes so solid that
the result was a circular wall of froz-
en- sand as hard as rock. The exca-
vators then removed the soft sand
inclosed by the frozen wall, Clipped
the wall into the form Of Al perfect
circle, put up a temporary "tubbing,"
and so proceeded downward. The
ground took seven weeks to freeze
The wall was approximately 10 feet
thick at the end of seven weeks
freezing, and four feet of this is be-
ing Clipped away, leaving six feet re-
manning. AS the hole deepens, the
pipes are carried down with it, and
the wall, once frozen, is t. be main
tanned in this condition until the
head is reached. Then it will
be- replaced by a brick wall, or rather
by two brick walls, with a bine mix
ture between them. BY the employ
ment of this method, pumping is dis
pensed with. No water can get
the frozen area, and it is as
safe from collapse as if it were solid
rock. The opening of the shaft is
covered up, and trap.doors
are provided for the passage of the ex-
earth and workmen. The in
terror OF the shaft at the working
is Illuminated with electric
light, and the cold is intense.