The Chemistry of Powder and Explosives - Sciencemadness Dot Org

NITROGLYCERIN 213
material in safety in the frozen condition. 29 He described an
explosion which occurred in December, 1870, in which the life of
a foreman was lost, and another in March, 1871, in which a large
amount of frozen nitroglycerin failed to explode.
The new magazine had hardly been completed, and stored
with nitroglycerine, when, on Sunday morning, at half past
six o'clock, March twelfth, 1871, the neighborhood was startled
by another explosion of sixteen hundred pounds of
nitroglycerine. The cause of this last explosion was continuous
overheating of the magazine. . . . The watchman con-
29 During the severe winter of 1867 and 1868, the Deerfield dam became
obstructed with ice, and it was important that it should be cleared
out without delay. W. P. Granger, Es»q., engineer in charge, determined
to attempt its removal by a blast of nitroglycerine. In order to appreciate
the following details, it must be borne in mind that the current literature
of this explosive distinctly asserted that, when congealed, the slightest
touch or jar was sufficient to explode nitroglycerine. Mr. Granger
desired me to prepare for him ten cartridges, and, as he had to cany
them in his sleigh from the west end of the tunnel to the east end or
Deerfield dam, a distance of nine miles over the mountain, he requested
them to be packed in such a way that they would not be affected by
the inclement weather. I therefore caused the nitroglycerine to be
warmed up to ninety degrees, warmed the cartridges, and, after charging
them, packed them in a box with sawdust that had been heated to the
same temperature; the box was tied to the back of the sleigh, with a
buffalo robe thrown over it. In floundering across the divide where banks,
road, hedge and water courses were indistinguishable beneath the drifted
snow, horse, sleigh and rider were upset, the box of cartridges got loose,
and were spread indiscriminately over the snow. After rectifying this
mishap, picking up the various contents of the sleigh, and getting ready
to start again, it occurred to Mr. Granger to examine his cartridges; his
feelings may be imagined when he discovered the nitroglycerine frozen
solid. To have left them behind and proceeded to the dam, where miners,
engineers and laborers were waiting to see this then much dreaded explosive,
would never do; so accepting the situation, he replaced them in
the case, and, laying it between his feet, proceeded on hi,-* way, thinking
a heap but saying nothing. Arrived, he forthwith attached fuse, exploder,
powder and some guncotton, and inserted the cartridge in the ice. Lighting
the fuse, he retired to a proper distance to watch the exi)lo;;ion.
Presently a sharp crack indicated that the fuse had done its work, and,
on proceeding to the hole drilled in the ice, it was found that fragments
of the copper cap were imbedded in the solid cylinder of congealed
nitroglycerine, which was driven through and out of the tin cartridge
into the anchor ice beneath, but not exploded. A second attempt was
attended with like results. Foiled in attempting to explode the frozen
nitroglycerine, Mr. Granger thawed the contents of another cartridge,
attached the fuse and exploder as before; this time the explosion was
entirely successful. From that day I have never transported nitroglycerine
excej.1 in a frozen condition, and to that lesson are we indebted for the
safp transmission of more than two hundred and fifty thousand pounds
of this explosive, over the roughest roads of New Hampshire, Vermont,
Massachusetts, New York, and the coal and oil regions of Pennsylvania,
in spring wagons with our own teams!.
Mowbray, op. cit., pp. 45-46.