The Sauk Centre herald. (Sauk Centre, Stearns County, Minn.) 1886-current, 1924-03-13
LIQUID OXYGEN
CHEAP EXPLOSIVE
U. S. Bureau of Mines Recon-
mends 1t for Use in Nom
Gaseous Mines.

Washington.-The use Of liquid oxy-
gen as an excellent and cheap explo-
sive in salt, metal and other nongas-
eous mines and in quarry and other
outside blasting, is recommended by
the United States bureau Of mines
after a series Of tests. Preliminary
experiments in this novel explosive,
conducted at the bureaus experiment
tai station at Pittsburgh, Pa. indicate
that it may be used to advantage
where dusts and gases are not pres
ent, but is especially useful elsewhere
In lessening the cost of blasting.
While liquid oxygen has not been
used in this country so far for this
purpose, it is already widely used in
Mexican mines; has been employed in
large quantities in the Upper Silesian
mines Of Germany since the war, and
has been adapted to tunnel work, iron
mining, subway and excavation work
in cities in that country. It was used
not only in Germany but in the French
iron mines Of Lorraine after the Ger
man seizure, and applied by them also
to the destruction Of French steel
plants. French officials Of the Briey
iron district believe the explosive has
come to stay, and the bureau is con-
Quoting negotiations with Alaskan
companies for its adoption there.
Production Cost Low.
An advantage is that it can be pre-
pared on the job at low cost after the
erection of COMPRISING plants, which
will make it Of especial value In
Alaska. AS liquid oxygen can be made
at the place Of consumption, dangers
common to the transportation of other
explosives can be done away with. Low
production cost, lessen!ng the cost per
unit Of material blasted, is another
advantage.
In the use of liquid oxygen explo.
sives there is practically no danger OF
premature ignition, it was found. The
danger Of misfires, too, is eliminated
by wait of 80 or 40 minutes after the
fuse is lighted, when practically all of
the oxygen will have evaporated. An
other advantage is the elimination of
the danger of unexploded sticks in
shoveling and subsequent handling of
coal or ore going out of the mine.
Other sources of danger avoided are
the handling and thawing processes
such as are necessary with frozen dy.
Mantle, and the hazard from lightning
or fire when stored.
More Power Than Dynamite.
But there are certain disadvantages
In the use Of this explosive, the blu.
reau says. Because of its rapid evap-
grafton liquid oxygen must be used
quickly and within a definite time
after the hole is charged, thus limit.
ing the number of holes that can be
fired simultaneously, although in Ger.
many as many as % have been fired al
once. It's use virtually requires the
installation Of liquidating plant at
considerable first cost, and this plant
must be kept running regularly to OBJ.
tain low cost explosive, as the main
cost is in the power used.
That the power Of liquid oxygen as
an explosive is favorably comparable
with other explosives is shown in the
fact that 100000 pounds of liquid
oxygen are equal to 100000 pounds
Of dynamite.
One of the interesting features Of
the high development Of this explosive
in Germany has been the designing OF
small portable liquid oxygen-making
plants to produce three liters an hour
Such plants have been constructed to
move about on trucks, making the ma.
terial much more available for small
operators.