Daily Kennebec journal., 1876-09-23
TIE EXPLOSION AT NEIL GATk

The tremendous and entirely nuexampled ey-
plosion in that part of East River, below New
York now known as He'll Gate, which event is
fixed for next Sunday, will certainly be very i'm.
portant in a scientific point of view. and it is
hoped win result In great practical benefits to com
merce. The area Of the reef which is to be oper-
ated upon is about three acres; two and three
quarters of which have been honeycombed and
packed at suitable intervals with explosive agents
The depth of water over the rock ranges from
zero to twenty six feet. The work of undermn
ing has been going on for seven years. and has
resulted in series Of excavations quite complica
ted as well as extensive. First, there is shaft
OF irregular five sided shape, III feet in one d.
rection by 62 feet transversely, and having a
depth of 80 feet below water mark. From this
shaft ten main tunnels radiate the tunnels vary
ing in length from 1855 feet to 300 feet--the aver.
age length being 30 feet The width of the tun.
nes is about IA feet, and their height varies from
II feet at the opening to feet at the end. The
excavation in all direcons-for we make no men
tlon Of the elaborate system of galleries. cross
tunnels. etc.-maintains at the roof general av-
erage Of ten feet Of solid rock between it and the
water above.
The work to be done therefore, in q moment,
on Sunday will be apparent at glance. 1t is to
blow up two and three quarter acres of rock ten
feet thick, lying under water to a depth of over
twenty feet. Now boats are passing over the lo-
cality, fishes are swimming in security, birds are
resting on the nelghborlng trees, aud all is peace
IN a few hours hence, commotion, as If BY the
bursting out of a volcano from the bowels Of the
earth, will IN an instant work a mighty change.
The agency which is relied upon to accomplish
the work is the threc-fol modification of nitro.
gyceriue known as dynamite rend-rock and yul-
can powder, employed according to their differ
ept explosive energies for the several varieties of
rock as they differ in hardness that there will
be sort of uniformity in the effect of the explo.
sion in its several parts. When we remember the
terrible effect OF a small quantity of dynamite be-
ing hred as by the villain Thomassen we can be-
gin merely to conjecture the enormous force of
such aR explosion as this which is to take place in
the East river. There are knownIto beat least $3.50
distinct charges arranged, comprising about 3S-
O0O pounds OF dynamite, rend-rock and vulcan
powder, and II is believed that several thousand
pounds more of the latter explosive are to be ad-
ded. For some reason those having charge of
the work are not disposed to be communicative on
the point. The explosive force of these nitro
glyceflne compounds is usually reckoned at thil-
teen times that of good gunpowder Being also,
er proportonate distention of gasses, and are,
therefore, more powerful on that score.
A peculiar feature of the explosion will be its
occurrence in, as well as under water for the
whole series Of excavations is to be flooded first.
The dynamite compounds are insoluble in water
so that Cromwelrs famous injunction about keep
ing your powder dry" docs not apply to them
and they can be- fred under water Just as well as
In ury ar, by means of fuse filed with prepa-
tlon Ike that Of percussion caps. These fuses,
communicating with all the batteries will unite
act 1t Is sand, will sbe performed by the daughter
OF Gen. Newton, who has charge of the work
HOW the explosion will manifest Itself to the spec.
tators passes all conjecture for there has been ma
instance OF a like process on sufficient scale ia
fern criterion. At the blowing up of a rock in
San Francisco haIbor in 1870, when Al, 900 pound.
OF ordinary powder were employed, a column OF
water 200 feet in diameter was thrown into tn,
air to hight variously estimated between two
hundred aud thee hundred feet. Around thi
column was an outer ling of water of enormou
bulk, about seventy feet high, and gradually rol
ling away. il remains TO be seen what will hap
pen at Hell Gate.-Bostoa Journal.