The Canton mail. [volume] (Canton, Miss.) 18??-1882, 1876-04-01
HE'LL GATE.
Forty Thousand Pounds of Nitro Giycefinc
TO be Exploded at one Pop.

eHao tCh ycdis hSo tuc Wal ocPdhthCh
> directed General John Newton, of tn
United States engineer corps, to max
estimates for the removal of the obstrue
tions in the East river, at Hallett's point
familiarity known as "Hell Gate"
The survey for the work was made il
: 1869. The work itself involved the re
D moval of the Middle Reef, Gridiron, Hei
and Chickens, and Negroes Head, virtu
ally the complete demolition of Hallett'
Point. In September, 1869, the frs
machinery was erected, and the work o
burrowing into the heart of the sub
merged rocks progressed slowly but sure
ly. The unwise delay of congress in ap
prOpriating the necessary funds, ana the
niggardly and paltry allowances made
hampered the advancemento of the scheme
At last, however, it is announced rs neal
completion, by the bulletin, that the
chamber prepared for the great charge
which is TO rend the stony mass to splint-
ers, and make He'll Gate terror of the
past, is as large as it is required to be.
By this explosion the eastern entrance to
New York will be opened to vessels OF
twenty-six feet draught. The cost of the
affair in money has been, so far, $3.50, 900.
The work has been under direction of
General Newton, and deserves special
record in the annals of American engi-
neering. At the extremity of Hallett's
Point, which is laid bare at low water,
a central shaft was SUM-, and the ledge
of rocks into which it descended was sur
rounded by a Golfer dam to guard the
workings from the high tides. From the
main shaft ten large headings radiated,
like the spokes of wheel, running out
into the river bed and under the reefs
which it was necessary to remove. From
these twenty-eight smaller drifts were
driven. The larger shafts, the chief of
which was two hundred feet long, were
named after various United States Off
GERS, as the Grant, Mcclellan, Meade,
ETC., galleries, and were connected at reg
ular distances by lateral galleries, circu-
lar in form and concentric with the CEN
ter of the shaft. Twenty-Five and halt
acres were undermined in this way, ard
mile and a half of tunneling made.
The great danger attendant on the work
was, of course, that likely to result from
the caving of the roof rock. To fully
guard against this soundings were made
all over the work at regular intervals Of
one foot. In ordinary cases the lead was
sunk, but where shale was met with the
patent sounding instrument was driven
through the bed rock by boring. But
few short of thirty thousand of these
measurements were required to establish
the necessary knowledge of the ground.
The best comment on the correctness of
the measurements arrived at is in the
fact that no serious case of caving in the
galleries has occurred since the work was
commenced. An enormous quantity of
blasting material was used; at first nitro
glycerine, but later an agent composed
of thirty parts of nitro-glycerine to sew
enty of gunpowder. This compound,
called vulcan powder, answered the re-
quirement better than any other, pro-
ducing the short, quick blast required,
to a marvel. Explosives, equivalent on
the whole to one hundred and fifty thou
sand pounds of nitro-glycerine, have been
consumed in bringing the work to its
present state. To-day the mine is ready |
to receive the final charge; in the pit or
chamber. which is thirty-five feet deep
and two hundred in diameter, ten thou
sand small holes, two and half inches
in diameter, and from seven to twelve |
feet deep, are being drilled in the roof
and sides of the passages for further blasts,
and are to be charged with the explosives
inclosed in iron tubes. In the matter of |
that explosive the engineers are at pres
ent in doubt. From the entire list of
blasting material at their command they
desire to select that which can most GER
tainly be relied on for effective work.
The choice has go far narrowed dewn to
two, respectively known as Kendrock and
pound, an especial favorite in the extern
sive workings of the Prussian mines.
The charges are to be simultaneously
ignited by percussion, with caps similar
in principle to those of a gun.
Forty thousand pounds of nltro-gycer-
inc are to form the grand charge. The
discharge of the various blasts is to be
effected by electricity, and, in order to
avoid the possibility of an irregular Sc
ries of explosions, General Newton pro- |
poses to connect the mines by means of
an electric wire inclosed in iron tubing
and carried about the entire workings,
directly with each blast.
A hundred and twenty men are at pres
ent employed drilling the holes for the
minor blasts, and twenty-one of them are
driven each dav. The effect of the dis
charge of this enormous magazine can
easily be imagined, and if, as the super
intsndent of the work hopes, its final
can be reached by then,
New York will hail her centennial fourth
of July with a right royal fire-cracker
indeed. The utility of the proposed ex-
plosion extends beyond the addition it
will make to our noisy national holiday,
and when the stately ships sail down the
sound, and New Workers, passing through
the East river, look in vain for the
seething eddies of old He'll Gate, the toll
of the long years will have its own re-
ward in the new gateway to our match
less harbor, which it has thrown open to
the world.
D1RWINI4N.
Discovery Of Fish that Thrires Only in
Harm Water.
Recently the workmen in one of the
California mines struck stream of water
at the depth of 1900 feet. 1t rose with
great rapidity until it reached the height