The Chemistry of Powder and Explosives - Sciencemadness Dot Org

368 DYNAMITE AND OTHER HIGH EXPLOSIVES
nitrate, varying from about 6700 meters per second for TNT to
about 4500 meters per second for 80/20 amatol. The greater the
proportion of ammonium nitrate the less the brisance and the
greater the heaving power of the amatol. 50/50 Amatol does not
contain oxygen enough for the complete combustion of its trinitrotoluene,
and gives a smoke which is dark colored but less
black than the smoke from straight TNT. 80/20 Amatol is less
brisant than TNT. It gives an insignificant white smoke. Smoke
boxes are usually loaded with 80/20 amatol in order that the
artilleryman may observe the bursting of his shells. The best
smoke compositions for this purpose contain a large proportion
of aluminum and provide smoke by day and a brilliant flash of
light by night.
The name of ammonal is applied both to certain blasting explosives
which contain aluminum and to military explosives, based
upon ammonium nitrate, which contain this metal. Military ammonals
are brisant and powerful explosives which explode with
a bright flash. They are hygroscopic, but the flake aluminum
which they contain behaves somewhat in the manner of the
shingles on a roof and helps materially to exclude moisture. At
the beginning of the first World War the Germans were using
in major caliber shells an ammonal having the first of the compositions
listed below. After the War had advanced and TNT
Ammonium nitrate
Trinitrotoluene
Aluminum flakes
Steanc acid
GERMAN AMMONAL FRENCH
I
54
30
16
II
72
12
16
AMMONAL
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had become more scarce, ammonal of the second formula wad
adopted. The French also used ammonal in major caliber shells
during the first World War. All three of the above-listed explosives
were loaded by compression. Experiments have been tried
with an ammonal containing ammonium thiocyanate; the mixture
was melted, and loaded by pouring but was found to be
unsatisfactory because of its rapid decomposition. Ammonal
yields a flame which is particularly hot, and consequently gives
an unduly high result in the Trauzl lead block test.
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