The daily dispatch. [volume] (Richmond [Va.]) 1850-1884, 1876-09-22
The IHell.Gato Explosion.

Gnsp % AuluHtSht, Or. /
The Hell.Gate Explosion.
GENERAL NEwToN's REASONS FOR EXPECTING
NO SERIOUS DAMAGE TO PROPERTY-RESULT
OF EXPERIMENTS MADE-How THE ExPLo-
SIvEs ARE DIVIDED UP--A P0STPoNEMEET
FOR FEW DAYS.
from the New York TribUne.I
A Tribune reporter called upon General
Newton ut his residence, in Brooklyn, last
evening, to make inquiries as to the truth
OF the reports that great damage would be
done to property when the Halletts-Point
explosion takes place. General Newton
said: a.
81 have seen published q statement this
evening. purporting to come from Mr..
Campbell, to the effect that he saw a IL
pound charge OF glycerine lift . rock weigh
ing ton and half over thirty feet out OF
the water, and that when the cartridge was
sixteen feet under water I wish to declare
this statement absurd and false, no matter
whom it comes from. That amount OF gly-
cerine has not the power to perform any
such work. We have fired upon Coenties
Reef 1,10O pounds Of glycerine simulta-
neously, in charges Of from fifty to
eighty pounds, and on that occasion one
rock weighing about ton was thrown
twenty feet in the air. That l saw myself.
1t has been proved by experiments at Hal.
lett's Point that it takes from one and half
to two pounds of nitro-glycerine to break
up one cubic yard of rock, and we have not
at that place, and will not have, more than
three iourths Of u pound of dynamite and
other explosives used-all Of which are of a
lower grade than nitro-glycerine-to every
or,h nd fo ho hrnI-an Vheca PynI0-
sives, when fired, are not to be exposed
openly in heaps on the floors Of the gale
ries, but are to be packed away in nearly
1000 small holes drilled in the rock and
separated from each other. 1t must be
borne in mind that the dam is to be pierced,
and that the whole work will be flooded
with water to the level Of the tides. The
charges, being tamped with water confined
in the galleries, will be compelled to per-
form their full work upon the rock, which
will leave no opportunity for the explosives
to escape and perform any eccentricitleS.
The quantity of work to be done by the
charge in each hole in breaking up the rock
is fully equal to the power OF the dynamite.
This is not theory. We know it from
practical experiments on that rock.
. snow, it is principle that work and
heat are convertible terms. The heat, there
fore, due to each blast-hole will be expended
in overcoming the resistance OF the rock,
and hence the gas which does escape, being
deprived Of heat, loses its tension, and con-
sequently its destructive properties, and
when it finally emerges in the atmosphere it
will have little or no dispersive action. But
in addition, this gas has not only to pass
through the rock through multitude OF
cracks and ruptures which it causes, but in
this divided state it has likewise to pass
through the water. parting thereby with
any heat that may be left in it. In addition
to this the gases formed by the explosion OF
nitro-glycerine contain in themselves great
quantity Of watery yapor, which will be
condensed by the cold rock and by the
water. 1t follows from these facts, which
cannot be contr0verted, that the effect on
the atmosphere will be nothing; or, on
the other hand, the only external effect pro-
duced will be caused by a few isolated
charges here and there partially escaping
through a seam and making harmless Jets OF
water. 1t is further made plain by
these facts that this casewill be entirely DIFF
ferent from the explosion Of a powder-mill,
or Of nitro-glycerine in the open air. In
these instances the whole energy OF the eX-
plosive is eXerted upon the atmosphere, the
waves Of which, propelled with disastrous
velocity, would destroy O neighborhood.
Hence it is very plain that the buildings in
Astoria will not be shaken by atmospheric
conclusion, such as certain critics seem to
be alone familiar with. A barrel of gun
powder in mass, exploded either in the air,
or embedded in the earth, would produce O
much greater effect than il it were distri-
buted over larger area in say fve-pound
charges. In other words, large quantity Of
explosives, distributed over large area, and
in small charges, would produce effects tri-
fling in comparison with the same amount
concentrated in one spot or divided into large
charges. This is precisely. the principle that
has been pursued at Hallett's Point. The
explosives are divided into comparatively
small charges over an area OF three acres OF
rock, each charge having its full amount OF
work to do in the rock. The conclusion
upon the rock will be that due to small
charges, and only to few OF those charges. !;
in other words, the conclusion In the rock
which will be propagated along the line OF
reef will be due only to the charges when
lie on the line OF separation between the
rock to be demolished and the part OF the
reef which remains. Finally, as q matter OF
course, the Government cannot be stopped
from prosecuting its public works by the
possible ehects-even If critics are cor
rect-which an explosion may have
1,pon property alone in the neighbor-
hood. Government officers are bound
to protect human life, and to do as little
damage to property as possible-that is all.
Further than this citizens must look to the
Government itself for damages, as the break
ing Of papes Of glass, the falling OF plaster
inc, or even the cracking OF walls in resi-
dences near by, should not and cannot stop
works OF national Importance. But also
wish to say that after giving to critics the
benefit Of all their assertions, am quite de-
cided in my opinion that the amout OF dam
age will be very trifi1ng."
In regard to the time for the explosion,
General Newton said he had not liked the
day. He would have been ready for tue
goth had the contractors been prompt in de-
liyering the explosives, but they We're SO
far behind thatit would be difficult to say
when everything would be In readiness. IL
was scarcely possible that the explosion
would take place this week.
[By telegraph.3
NEW York, September 21.--At nine min
utes to 8 O'Clock on Sunday afternoon, Sep
tember Oath, 90, 600 pounds, OF explosives.
packed in the mine beneath the rocks OF
Hell Gate will be fired. The tide Will at that
moment be at its highest, and It is thought
the river will be less crowded by vessels on
their way out into the Sound than at any
other time. II fstt s.8
There will be perceptible shaking OF the
windows of the houses IN Astoria ut the
time OF thsIexploaion. After the finishing
OF the prsming on Saturday orning sthe
shaft and galleries viii be flooded quietly Tby