Although the accident in the tunnel in process of construction at Union
Hill by the New York, Ontario, and Western Railroad Company, which took
place on Tuesday afternoon, was happily attended with no loss of life or
serious injuries to the men employed in the shaft, it reads a new lesson
as to the firing of charges of powder by electricity, and one that
should be carefully noted by railway and civil engineers, and even
by the torpedo service of the United States. The exact cause of the
explosion has scarcely been fully and accurately set forth by the
various reports of the affair.
It appears that the wires usually employed lo supply the electric lamps
in the excavation were used for the purpose of firing the charges, being
disconnected from the electric light system for the moment and connected
with the explosives. As a rule, six charges were fired together, those
of the afternoon relay of men being exploded at very regular hours--the
last usually at 5:45 P.M. There were only sixteen men in the shaft,
and the work of connecting the wires had commenced, when the flash of
lightning that occurred at 5:42 P.M., suddenly charged the conductors
and produced the explosion.
There were two flashes of lightning between the hours of 5 and 6 o'clock
Tuesday afternoon, the first taking place at 5:23, and the second
nineteen minutes later. The former, according to testimony elicited by
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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