SCIENCE AND INDUSTRY. 
But its industrial use is new and almost untried, and because of the — 
name of terror it acquired during the war, many who would handle the 
familiar dynamite of the mine, the blast, the quarry, the tree stump, 
the log split, or the ditch-digging operation fearlessly, shrink from 
T.N.T. That they shrink without real cause has been demonsirated — 
by careful and exhaustive tests conducted by the Bureau of Minés, _ 
which has shown that it may not only be employed with greater safety i 
but with greater effect than the familiar explosives of industrial use. 
Without going very deeply into the chemistry of the substance, it 
may yet be interesting to consider it for a moment as a substance rather 
_ than as an explosive. T.N.T. is produced by the action of nitrie acid 
upon toluene in the presence of sulphuric acid, ‘Toluene is a_ soft- 
coal product, obtained as a by-product in the manufacturing of coke, 
coal gas, and coal tar. There are many nitro-toluenes, hence the dis- 
tinguishing of this particular one by the “tri” which indicates its 
chemical composition. 
It appears as a pale, yellow crystalline substance, which darkens to 
a deeper yellow and a brown under the action of light. It is very 
slightly soluble in water, melts at about 177.9 degrees Fahrenheit, and 
can be cast, like any molten metal, when so melted, or dropped into 
water and solidified in globules or pellets. The T.N.T. allotted to the 
Interior Department by the War Department from its large war- 
provided store, for allocation to peace uses by various Government 
activities, such as the Office of Public Roads, the Reclamation Service, 
the Indian Office, &c., is in three grades, differing in the temperature 
at which it solidifies, and in purity. Pure T.N.T. thas a faint odour, 
tastes bitter, something like quinine without the permeability of that 
chemical on the mucous membrane, and is to some cxtent peisonous, 
though not fatally so without large quantities or great exposure. 
Nitro-glycerine is so powerful a heart stimulant as to find a place in 
materia medica, and, as is well known, produces severe headaches when 
allowed to come in contact with the person. T.N.T. requires a much 
longer exposure to produce its characteristic effect—a rash or skin 
breaking out—and can be handled without danger if gloves are worn, 
and it is not allowed to touch mouth, nose, or eves. 
T.N.T. needs a more powerful detonator than either nitro-glycerine 
or dynamite. The statement that the extra powerful detonation re- 
quired for T.N.T. means increased expense for use is hardly borne out 
by the facts. A couple of pennies covers the extra charge (no pun is 
intended) with something to spare. : 
T.N.T. is not so sensitive to friction as 40 per cent. straight dynamite 
(the familiar explosive of blasting operations), gelatine dynamite, or 
even picric acid. It is less sensitive to percussion than the dynamite 
and several other well-known explosives. . It may be fired and burn 
peacefully, but it may be fired and iurn its flame to a detonation, so it 
cannot be said to be fireproof. The results of the explosion of T.N.T. 
are six different gases: carbon-dioxide, oxygen, carbon-monoxide, 
hydrogen, methane, and nitrogen. The proportion of the poisonous 
gases produced is about forty-six to fifty-four of the non-poisonous. 
Forty-six per cent. of poisonous gas as a result of an explosion is too 
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