The New York herald., 1876-09-18
SURFACE DRILLING AND BLASTING.
The Grand Excavation-How It
Was Accomplished.
PRIMERS AND CARTRIDGES.
Final Destruction Of the Reef in a
Few Days.

completion under most trying circumstances "nen
the undertaking was first commenced the engineers
found vast reef, extending many hundred feet into
boiling caldron OF ioaming water, glance ut which
enough inspire fear the breast Of the bodest
navigator Only small portion, close to the shore,
Of this rocky projection visible at low
water, the remainder being hidden beneath the
angry waters that whirlod over u, causing
hundred eddies, each Of which seemed
TO mark the hiding place OF some submerged monster
whose hungry NAV gaped Tor victims. Sometimes
whea the tide had reached It's full height de-
sctul calm would rest the face OF tho water
rho floating weeds and other buoyant objects pass
slowly by with sluggish notion as II in mockery Of
.he turmoil that Ia 10 follow. Gradually this
movement grows swifter the disturbance Of lcvel
between the basins OF the Sound and New York
Bay becomes greater and tremuous rip
plc appears on the surface OF the water, as II
gust of wind had struck It aud agitated nttuy. But
although profound calm may prevail and the swa
lows skim gracefully the broad stretch Of water
that extends toward Harlem and Wards Island, tho
mysterious movement Of the water continues to grow
In orce and the lately PLACID surface is broken into
that umpy which indicates that change In
It's condition is at hand
Soon a streaky appearance takes the place Of the
strong ripple and the stream attains velocity which
can only be occasioned by a considerable head. Here
and there fierce, gu.py motion If i'm
mense FISH suddenly 10 the surface to seixe its
prey Tho streaky lines develop into distinct outlines
OF currents which converge and diverge again with
surprising swiftness These observed to be de-
aec,cd by hidden obstruction to their direct
and turn sharply back on those adjoining,
causing piling up of the water into dark
green hilocks which break at their bases into foam
and seem to bury themselves in the depths beneath
A floating log comes along borne rapidly toward the
rho Il odyo h;rlc n
round as II in sport with the Suddenly 1t is
saught by another and violently away
hurried back tho centre of tho river whore
rolled and under the waves, and disappears for
at time in the dark recesscs OF the river bed
Meantime the foaming and whirng outside increases
the dark, rugged heads Of rocks liftod for
moment OF the rushing river and again plunged
beneath It's surface These to be gifted with hfc
Tor they an imaginary motion which causes the
doubt that they only the solid pinnaclcs
Of rocky structure beneath and not the upturned
Jaws OF h!deous leviathans that guard the dreadful
passage Masses of water rise II lifted bodily by
eome unseen power beneath and plunge again into
depths created beside them.
All now is changed from the placid smoothness 80
atcy bened into of violence that fairly battles
descriptions The force Of tho currents that dash
ady over sunkcn reefs dnd chase each other
violent rushes around the rocky is immense
Il seems impossible that any effort OF human skA
compete with their tremendous energy. They
howl and roar and surge along II in
litter defiance of man and all his boasted
power New rocky monsters thrust their heads
water every moment to add TO the general uprosr
pf tho waters They appear make efforts stay
whrlpoos to grasp At The waves that rush past them
with shrek If Of fear and hurry away from tho
horrid jaws that would cngult them such is the way
the waters come down at He'll Gate II Is daily
~" hs viii on rs ond
bosom the commerce Of New York II will float
10 our wharves tho great ships that cross tho ocean
greightcd with the wealth OF distant countries. IL |,
becomes a highway along which thousands hurry |
daily pursuit of wealth and pleasure and therefore
assist the river IN IT'S battle with the rocks Tho
latter are ike wolves that menace the traveller In /
bis journeyings They lie in wait for tho ship 1
as she gracefully advances with her sails filed /
BY avorng winds. They mcrcilcss In their !
savage assaults her trail sides and weave net |
works Of currents entangc the navigator their
meshcs before they dcvour him. Such being the case
regard the rocks our enemies and We organize
campaign against them as against human ioek wo
,ly steel and undermine their stronghoids, and /
Ihen shattcr their entrenchmcnts ana themselves |
Snh enormous charges Of the most powerful explo-
How this is accomplished in the case Of the great
Jcct Hacts Point the special subject OF the pres
ent article.
This immense mass Of sralned gnciss rs dangerous |
10 the navigator OF the East River passage to
The sound as the tabled Charybds the wander
ng Ulysses and his companions has already been fully
described in the llEnALp articles Its influence on tho
sbb current through He'll Gate Is decided that |
Improvement could be said 10 have been !
made that difficult chsnnel unless II m
rolved tho destruction OF this reef Not only |
does the projecting rock represent local danger
navigation which would warrant large expenditure
On destruction, but It also compcaes the difficulty
experienced by ships avoiding other obstructons.
rhe set OF the ebb current may be said to be controlled
entirely by IIactt's Point, which presents sharp
Salient around which the waters whirl with immense
vcocy. Although the rock slopes gradually downward |
ind outward from the point Of land. u causes the |
to accumulate slopes and creates tall IN
hc direction OF the current Vessels that cntanglod
the counter currents are liable TO be drawn high up
han NIL upl ltaup I'd
Eed slope, striking violently as they move. and rc-
aucnty thrown completely on their beam ends toward
Al accident OF this kind occurred only few days
sgo while a small vesse being ,owed around the
point She seemed TO have been lifted bodily the
rock by rush Of the water and then
10 much render her position extremely pcrilous
Fortunately, however, the assistance OF another lug
was procured in 10 prevent disaster. and the
vessel was dragged or tho rock into deep wpcr.
Tho accompanying cut, NO. !, shows the character
OF the excavations by General Newton The contour
lines marked the sketch show how the ridge pro-
ccts into tho channel The outline Is that on the
line OF thirtytwo foot soundpgs. 1t VIII be readily |
how important Is to cut OF the projection and
batcn The curve necessary 10 be followed in rounding
The reef
TIE EXCAVATION
Tho ohof object OF this undertaking TO cut of the
reef at line which will facilitate the passage of
vessels close shore but as the rocky swept
by violent currents during the cob and now Of The
face blasting ras failed make any impression
upon IT, several difficulties presented themselves
when this work was attempted By Mnillccrt IN
eighteen. The effect OF nro-elyccrine as submarine
explosive is calculated TO shattcr promnenccs the
rocky ana even 10 break lodges that project
upward from deep wafer. Its force being as great
downward upward II dctachcs isolated masses from
their beds by crushing then with n titanic blow
But where large surfaces present themselves the
resistance is greatly increased and a limit Is
reached when even nitro-gycernc produces no
visible effect the formation Rocks Ike the FRYING
Pam the Pot Rock and others oi the same class were
rut down by the SIMPLE process OF suriacc blasting
untl OF suriacc created by repeated detach
ments from the main buik became too largo and the
plan had 10 be abandoned. Much usc.uI work
vas accom- Pushed by the surface blasting The
water was In several instances dcepcncd from
e,aht 10 sixteen iect and tho Jagged points
q the rocks were cut OH. leaving wnat might