The New York herald., 1876-09-16

know it is they will all be Disguised and go away do
claring the work big humbug. Why change
In the water level will be than from one to
two feet after tho explosion People In general have
nm IDEA that, as We have made cavern lfteen or
twenty feet deep under the bed OF the river the
superintendent roof OF rock seven feet thick,
will fall into the hole and leave hteen of clear
gain in the depth OF the river. That is great
take Tho pillars and root when shattered pieces
will occupy at least twice the space they I'll in solid
form, that the real gain in depth OF will
perhaps not more than a foot until after the broken
rock has been dredscd up" The OF graphing Tor
and removing tho debris OF the reef after blast VIII
occupy at least one year, with plenty Of funds,
and Il very doubtful at present whether money
will be forthcoming. Congress appropriated So 400 O0a
for harbor improvements tho present year and the
President signed the bill in due course Within few
weeks, however, he has declared that not
81 OF the appropriation shall be expended,
that the officials at He'll Gate VIII get put two-iths of
the amount they expected General Newton, when
questioned on this subject very reticent
and turned the subject by revcrtng TO tho expected
''show" on Thursday next, when the mine is TO bc
fred When asked II there would not be very severe
earth felt along Manhattan Island ho replied in
the negative The shock, he thinks Will not be felt
down either by concussi, Of air earth
Localities along the line of tho reef may he thinks,
experience slight shock at distance OF half mile,
but il will not be enough to do more than rattle
shaky easements There now about 80, 600 pounds
OF explosives the nine, and the entire amount 10 be
used VIII be between ~, 900 and 5ooOo pounds How
alarming these hgures may seem when one re-
members tho dire effects produced by the explosion OF
a few ounces of the dreaded compound the effect will
not be terrible as would seem on the nrst appear
Many persons expect an earthquake because they
fancy that dynamte exerts all It's force downward in
an explosion, differing in that respect from gnnpowder,
which they think 'explodes upward" This Is
great mistake IL s true that If small quantity OF
gunpowdcr be placed upon table and touched with q
lighted match 1t Will burst upward and leave the
table unharmed, except, perhaps, that II may be
slightly he'd by the heat generated and that dyna-
mite exploded under tho same circumstances
will go down through tho table Both COM
POUNDS, however, explode spherically--that Is.
with equal force In every direction from the centre;
tho explanation Of their different action In tho
mentioned is due to the fact that gunpowder can
hardly bo said to explode at all under such cIrcum-
stances slow is its combustion 1t generates gases
slowly that the latter have time TO force aside tho
atmosphere and as that oilers ess resistance than tho
the tablo all its expansion takes place and
all its force is exerted in that direction Dynamite, on
the other hand generates gases SO fast that the air
cannot possibly be crowded out OF the way quickly
enougiynto make room Tor them, less resistance il
offered by the table, and consequently, through the
GENERAL sEwroS's THEORY
is that all the charges in the pillars and roof will havc
Immediately surrounded and that they Will produce
little no effect beyond that He excepts The
charges that are located At the base Of
the pillars from the floor. These are the
ones which VIII produce whatever slight trembling OF
the earth may occur when tho mine is blown up
and the General thinks that there would be greater
shock felt If thrice the quantity of explosives were
packed in tho stone above the points where
the pillars join the floor. On the whole no is afraid
that In be cautious and prepare the residents
reef for the shock, he has actually made tho
blowing up appear Of much more Importance than II
really is. Many wseacres OF the vicinity, however,
snase
force crush continent, land where, they ask. ia
In IA holo, tho rIvc al the
steadily olling, and had tho contractors furnished
the material on time the wholc nine would now DO
charged ready tor the prners Owing 10 their delay
however The charging will hardly be completed
day The primers, or explodcnt cartridges, are almost
ready for use, and should fresh supply OF dynamite
arrive this evening the work OF prmng the mine will
probably begin at once and be completed morrow;
lor although tho officials TO laboring tho
Sabbath they viii consento u In view OF the fact that
tho labor OF hundreds OF for nve long years. not
to mention the mint OF money expended, may bo
destroyed In the wink OF an eye By some accident
which would at the same time pow der INTO dust every
body within half mile OF the place; when they con-
slider that TACT they are anxious to have
tho whole business over as soon as possi-
BILE. When the primers arc all attached tho
cavern will be slowly Hooded by means of syphon up
the level OF the river Tho syphon Is now In posi-
uon and II Of heavy IRON pipe twelve inches
In diameter. A bend at the lower end throws about
four feet OF It horizontally along the floor OF the shaft
while the elbow projects horizontally out into
the river snort distance below the surface The water
will be admitted by ling a valve at the top, and
flowing through the ply nd along the bottom Of tho
headings will rise so slowly as not to displace any Of
the charges sweep away the wires. About one day
will suffice for the flooding, and the mino VIII bo fired
soon after that event possible
Every possible prccauion has becn taken IN guard
against accident at every stage In case oil thunder
arising after tho primers are in place, and which
might perchanoe dart along tho wires and cause
mature explosion, the ends OF each pair OF wires viii
ioncd together complete the circuits, and then
all the ends will be thrown into the river, 80 that II
tho electric fluid should strike any portion OF them
will be dlsspated by the waters establishing an cquh
lbrium.
On tho day OF the bast-probably on Wednesday OF
Thursday nextnmost the entire police force OF Lona
Island City viii be drawn up IN GORDON around thl
mouth OF the SHAFT az little distance. 10 keep back
the crowd the river police of New York VIII be on
hand in their boats to keep at distance the hundreds
OF small boats whose eight seeing occupants wsuld
permit their curiosity overcome their discretion.