Evening star. [volume] (Washington, D.C.) 1854-1972, 1907-06-01

plosiOn takes place, thus reducing the
shock and preventing destruction Of the
plant-a provision somewhat important.
Watching the Explosion.
That those witnessing the experiments
may see the flash Of the explosion, series
of port holes. covered with half-inch plates
of glass. will be arranged along the side OF
the big tube. These will be on a level with
a row Of horizontal Sits, covered with
heavy plate glass. in the fortified observa-
ton house, sixty feet to the side OF the
tube Through these Sits the flash Of the
explosion will be watched as it flashes down
the line of port holes or blaZes from them
all simultaneously. In order that operators
and miners at the peep holes may clearly
note the time of explosions the lid of one
of the safety valves will be opened, and
across the mouth will be stretched dia
phragm of oiled paper, which, when the
explosion occurs, will blow out and allow
a piece of guncotton, suspended upon
bracket above to ignite.
The fire damp will be fed to the big cylin-
der through a tube and gas meter. which
latter will measure the amount admitted
The fire damp will fall to the bottom of the
tube until thoroughly mixed with air This
will be effected by the electric fans. which
will suck both air and gas out Of one end of
the cylinder, and which. after energetically
churning them IN. will force the mixture
back into the other end. this circulate ton be-
ing repeated until the gas Is thoroughly dis
tributed. This entire explosive gallery"
will be modelled after-and a slight improve
ment upon-that Of the Belgian administra-
ton Of mines. at Frameries Mr. Clarence
Hall. the geological surveys explosive ex-
pert who lately returned from a tour Of
inspection of such stations abroad has
placed at the writer's disposal the accom-
panying picture of the Belgian plant 1t
gives some idea of how our own will ap-
pear.
Dynamite. black powder and the various
safety explosives including the ammonia
nitrate class. will be exploded in this great
tube OF course. any Of these, If used in
sufficient quantities. will ignite fire damp
or coal dust. But the tests will determine
the maximum charges which can be used in
mines without causing fire damp or coal
dust explosions. These will be listed by
the government permissible explosives"
and adoption of such standards will be
urged upon mine owners. AS a result of
such experiments in England Mr.. Hall
noted number of permissible explosives
which. and no others. must, by law be
used by the miners in blasting coal. Eng
land also preScribes limit charge"
which must not be exceeded on pain of
severe penalty.
The Rescue Room.
rescue room" resembling the interior
of a mine will be another adjunct of our
new station. There will be apparatus for
filling this with smoke and a course of in
struction in the art of rescuing miners will
be given. The efficiency of all sorts of in
yentions fer sustaining life after mine
blossoms will here be tested. After serious
explosions in our mines hundreds of lives
could be saved. they are abroad. were 1t
possible for the rescue parties to penetrate
The smoke or gas Immediately after the ac-
c,dents Under present conditions in this
country the deadly fire damp often holds
the rescuers back for hours while their