The Anaconda standard. [volume] (Anaconda, Mont.) 1889-1970, 1898-12-10

lose much Of the nitroglycerine and be-
come weak; II In a damp place absorb
moisture n become weak.
Probably two-thirds of the fatal acci-
dents that nave happened with dyna-
mite have come from careless methods
OF thawing. Dynamite freezes about 45
+. In this condition II II stiff and hard
and should not be used for blasting, as
IL is i%nsensitive to the ordinary deto-
nator. The powder Is a poor conductor
of heat, and for this reason IL freezes
and thaws slowly. The time equire
to thaw IL thoroughly when II is once
solidly frozen In much greater than
most people think. Shut UP In the
boxes in a magazine. IL will remain
frozen even In summer for many
weeks.
The thawing Of dynamite is always
attended with danger IL II Is done rap
idly at a high temperature. The dan
ger is In direct proportion to the tenn
perature. No matter how urgent the
haste may be, the temperature used
should never exceed 100 +. A dry heat
should be used-that is. the powder
should not be brought in direct contact
with hot water or steam. Water tends
to make the nitroglycerine exude and
also attacks the chemical salts in the
composition. Where the object justifies
the expense Il is a good plan 10 keep
the interior of the magazine at a mod
crate temperature. say OV. WHICH VIII
prevent the powder from freezing.
Steam pipes should never be used in
side of a building where powder Is
stored. The best method Of heating is
the well-known hot water system used
for dwellings. In this the circulation
Is active and the arrangement such
that the water cannot be brought to
the steaming point or even be over
heated. 1t has been found that a maxi
mum temperature of 104 degrees in the
water gives an active circulation. The
heater Is located at a safe distance n
the water circulates through pipes in
the building and returns TO the heater.
The pipes outside the building are well
protected and covered to prevent less
OF heat and the building should be
made as impervious to heat as pos
sible.
Double walls. floors and ceiling with
a saw dust filling answer every pur-
pose. but the building must be made
absolutely tight. a crack under a door
or window will counterfeit the best
heating system hat can be made.
II steam Is available a very cheap
and efficient system of heating a small
building Is as follows: On the outside
of the building a sheet iron drum Is set
up and connected with another inside.
Two pipes pass through the wall, con-
Meeting the drums near the top and bot
tom. The outside drum is set n little
lower thai the other to provide for the
overflow of the water. The holes
through the walls are packed around
the pipes with waste or tow. Water I'm
the outside drum is heated by a small
steam pipe and circulates through the
drums. The room Is kept warm by the
radiation from the inside drum. III the
building Is tight and properly insulated
the amount OF steam necessary Is very
small. To prevent the vapor from max
ing the damp. the drums are
closed on top with wooden lids covered
on the under side with cloth soaked In
parafine. The sheet iron drum USED
for the transportation of glycerine or
| coal oil Is well suited to this work.
When dynamite is being used in win
ter on a large scale. as at a mine, IL
woul pay to build a small thawing
room OF this kind. say 12xl6. The pow
der needed for the days consumption
could be carried in and left for IL hours
or more-the boxes being simply opened
or the powder taken out n put on
shelves. depending on the time availa-
BILE. A temperature of as or so degrees
maintained during the night would suf-
flee TO thaw the powder. A thermome-
ter should always be consulted to reg
ulate the temperature of the room.
which should not exceed SIS degrees.
This particular arrangement for n
ina lIE Iooill 4 = CotlNtnltIAs bul II may
be varied to suit the case. m essential
feature Is a tight. heat-insulated room
kept at a moderate and regulated tenn
perature.
The plan of a thawing room is much
better than using thawing stoves. The
best OF these are liable to get out of or
der. IL not originally dangerous. The
thawing room has great capacity so
that the work need not be done in a
hurry. n has always this advantage
over small apparatus. Any excess OF
temperature brings discomfort to the
operator and so gives warning. A room
In which n nan can work without dis
tress Ii reasonably safe for thawing dy-
Mantle.
In no case should any apparatus for
thawing powder be used in a magazine
or building where a large quantity of
powder Is stored. The same warning
applies to the handling of caps i'm the
preparation OF primers.
Charging.
In charging a drill hole use a wooden
tamping rod. IL the hole is dry, cut
the cartridges into short lengths and
slit them along the sides. so that when
driven down with the rod the powder
will spread and MI the nequalization
of h hole. The primer with the cap
carefully attached should be put in last.
that is on top OF the charge. The hole
is then to be filled and tamped with
care. Earth or clay. mixed with grav-
ell. makes one OF the best tampings. In
n wet hole leave the cartridges intact
for the better protection OF the powder.
The water which surround the cart
ridges will transmit the blow to the
rock. but use tamping in every case.
Some miners do no think II necessary
but il Is the only way to get the best
results. The powder gases e n TO act
I'm the line OF least resistance. IL this
work is not properly done a part OF the
energy will he expended through the
open drill hole or in blowing out a weak
tamping before the gases have done
their work on the rock.
There are two reasons for putting the
cap at the top of the charge. III IL is
buried In the mass of the charge the
fuse In burning down to II may set
fire to the powder by side splitting and
burn up a part of II before the cap