The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1885-10-10
OPENING HE'LL GATE.
Everything in Readiness for the Great Ex-
plosion-A Visit to the Rock.

New YORK, Oct 19.-The great explosion of
nearly 100000 pounds of dynamite which is
pected to SILVER Flood Rock and clear He'll Gate
channel, is set for tomorrow morning, about II
o'clock. The work of clearing away the machin
cry, buildings and other valuable property was
completed tonight, and all that remains are the
elevator timbers over the main shaft and the
little tool shantes, which have been cleaned out
and fitted up with shelves that hold the great
battery that will cause the explosion. The
thirtysix wires that communicate with
the detonaters hang in bunch.
Since early this morning, two eighteen-inch
syphons have been running water into the mine,
and it is expected that the whole will be flooded
by 6 A. NJ. tomorrow 1t has been decided to
| locate the land battery and instrument on the
old Astoria dock, and the wires to complete
the circuit will be run across the charnel to-
morrow. Cordons of police will keep the crowds
at respectful and safe distance, and owners of
buildings in the immediate neighborhood have
been notified to stand from under. Steam
launches from government vessels will patrol
the river and prevent vessels from passing
Immediately after successfully removing the
Halletts Point reef. in 1876, the engineers began
work on Flood Rock where shaft sixty feet
deep was sunk. from the bottom of which gal
leries were driven in all directions. All the
passages are twenty five feet apart; but
while some of them are twenty
feet or more in height others so low that in
walking through them man must bend his
head in order to avoid hitting it against the roof
The height of the galleries depends upon the
depth OF water in the river above them, and the
thickness of the roof depends upon the character
of the rock of which it is formed that varies
from fifteen to twenty feet. In this roof and in
the walls and pillars supporting it nearly $4,000
holes have been drilled and filled with copper
cartridges. containing dynamite and rackarock
powder The holes in the roof were drilled by
threes, one directly upward in the center of the
gallery, and one at each side, but inclined out
ward at an angle of 45o. Each is ten feet deep.
and thus every pair of side holes in adjacent gal
leries approach each other. The weight of the
explosive material with which these holes are
charged is 275, 600 pounds, nearly six times
much as was used in blowing up the reef at Hal
let's Point; and the result of its discharge will be
an upheaval grander and more terribly destruct-
tive than anything of the kind ever before con-
ceived and effected by men, Of the immense
number of cartridges used to produce this explo
sion only two or three thousand connected
with each other and with the firing battery by
insulated copper wire the suppositlon being that
the conclusion produced by the firing of these
will explode the rest The placing of the cart
| ridges was finished about the last of September.
writer who visited the work few days since
just across the reef from Flood Rock, was large
sign that read, Nitro glycerine-Don't Land"
Beyond it was rough shed, in which men were
carefully mixing chlorate of potash and black
Oil that they called dinitro-benzole. These harm
less ingredients when combined, formed the ter
ribly destructive rackarock, which is the prnci-
pal explosive to be used in destroying the reef.
1t looked like wet and inferior grade of brown
sugar, as it was being mixed in leaden trough
by two men, who used wooden hoes Only fifty
mi a a nd wa
put into the copper cartridge cases, rammed
down with a wooden hammer, and the tops of
the cartridges were soldered in place by means
of steam heated soldering-irons
The prepared cartridges were set in parttioned
wooden boxes. each of which held dozen, and
a dozen or SO of these boxes were taken on
board the tug and carried over to Flood Rock,
where. with the utmost care, they were landed
| and lowered down the shaft into the mine.
Here the scene was the same and yet very
different, from what it had been while the ex-
| cavation was in progress. The ominous silence
was unbroken save by the rush, splash or steady
drip OF the encroachlng waters, and the throb of
| the great pumps that worked increasingly to the
| very end to keep the mine from being flooded
there was noise of busy steam drills nor rattle
of stone-laden cars. The men who handled the
cartridges were grave, sober lot, who worked
In silence, with Iull consciousness of the awful
| hazard they were running, and a knowledge of
| the terrible consequences that might follow
| single misstep or careless motion Some of
| Them mounted on ladders rude platforms, re-
ceived the cartridges as they were handed up to
Them and carefully inserted them in the holes
! that had been drilled for their reception push
| ing them home with wooden hammers. In
| every few inches of the last cartridge
were allowed to project beyond the hole, in
which. if they were loose, they We're held in po-
sition by little brass spurs projecting from their
rims. Over fifty thousand of these cartridges
were thus placed before the mine was pro-
nounced wholly charged and ready to be ex-
ploded.