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Scientific American Supplement, No. 324, March 18, 1882 by Various
page 37 of 143 (25%)
our reporter, simply caused a slight perturbation of the lights in the
tunnel, but did not extinguish them. Five minutes later the work of
disconnection and reconnection began, but only two of the six charges
were ready for the pressure of the button when the last flash
interrupted the proceedings. The fact that the time of the explosion
corresponded to the second with that of the aerial electrical discharge
furnishes indubitable evidence that the accident was not caused by any
carelessness on the part the electrician in charge, and exonerates
all parties from blame. At the same time it should be remembered by
engineers in of such work that atmospheric electricity cannot be
altogether disregarded in such cases, and that as a source of accident
it may at any time prove dangerous. The concurrence of circumstances on
Tuesday was particularly fortunate. In the first instance only two of
the six charges had been connected with the firing battery, and in the
second the rock in which the charges were inserted was so peculiarly
soft and porous as to deaden the force of the eight pounds of giant
powder thus prematurely set off. Had the cartridges been set in the
harder and more solid rock of the east heading, instead of the west, and
the explosion taken place there, probably not a man in the shaft would
have escaped destruction. The lesson to engineers is one of no less
importance than if the whole number of men had been killed, and should
lead to the exercise of great care and precaution at times when the air
is charged with electrical energy.--_New York Times_.

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