New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1900-09-30
SUBMARINE BLASTING
REMOVAL OF THE "IIAN-o,-vAp, -.
THE EAST RIVER - AMERICAS
TRIUMPH IN SUCH WORK

In the middle Of the East River ia an -,
that occasionally heaves out OF the vrats- 'ooE
struck by the nose OF some sea monster n. = Y
Is anchored just south OF BlackweIFs Isl.-s ~
gang OF men are busy on the deck. and a.. 4
steam engines are industriousy pufHns, -, 'sf+
spouting water After period Of active -. sai
ton a long shaft IS sunk down into TIE E.sDaTa-
men stop working. an electric dynamo 4 - ',s
motion. the brushes on the armature NO. q
ting blue flames, and the big scow h,n.-- VI
quivers on an uprising surge. The next r.s- ana
thousands OF bubbles come rushing IN ~. 1-e .at
whitish smoke. '--a q
Such are the outward signs OF bIasti,z
waters OF the East River with a ebsrvs - =. ss
pounds Of dynamite. The ugly scow 4 s,..,I- ~
by the K g. Packard Dredging Companv 4, -
moving the big "Man-o'-War Rock. wbicb
cause OF being submerged only little beneath =.
water has long been source Of peril TO vravss7
mariners 1t has been called the ..Nrar,, -rs
Rock because OF its resemblance at lou -
a low hulled ram
The spectacle Of men coolIy boring a bors -,
them. charging 1t with enough dynamite - ,...
stone house ashore. and then touching II on -.
at first thought to be a counting OF car-at, -
The great resistance Of the water hovva,e an
inelasticity enable these men to hover over - -
plosion which in open air would blow ,be-, :
fragments.
Work on the "Man-o'-War Rock beza, a.
six months ago and is expected to be A7f-bos 4,
March l. 1901. The undertaking involves the -
InoVaI OF about two acres OF irregular rock which
in some places energies from the water AZ lon, go
and in other parts turks few feet below -
channel is to be dredged to a depth Of r5ir,-
feet, which will necessitate removing more IT,
nineteen thousand cubic yards of rock.
The blasting Of the rock under water rsout-..
first the boring Of a hole down. This is aeon
plished by a steel drill five inches IN diar7a.s- :.
md Of Ions sfa
securely TO an iron column which extends dov
from the side Of the scow to the rock level IA,
drill is forced down by hydraulic pressure Fom,
such drills at work. each on a column A. -
sides Of the scow. and the drill is forced dOz-
water is pumped into the bottom Of the hi.
through feed pipe in order TO wash away The
sand.
When the hole is completed the column Is haulss
out Of the water by a derrick engine A Ions
cartridge. containing from twenty 10 sixty pOuu5s
OF dynamite. is then sunk into the hole and Il
touched off by a spark from the dynamo
ment slSs0 SG''' '"'S isOss VIII cost the Govern
Blasting under water has been conducted mOrs
successfully in the United States than in am
other country. Engineers o. the Old World fou75
themselves particularly embarrassed by the mis-
the Danube, rocky pass. fourteen hundred yards
wide Just below Orsova, Austria. at frs
and carefully studied the WORKINGS of a nIan4 e.
company employed in dredging in Lake Erie near
Buffalo. The engineer returned 10 Europe and IL
PRODUCED the methods he had learned here, with
successful results As another token Of American
superiority in this line of engineering a Chicago
firm has been employed 10 dredge out the River
Don.
Similar work to that now in progress on the
''Man-o'-War Rock will soon be undertaken on
the ledge just on the Battery where the steam
ship Havana aground about month ago
This obstacle has been struck Uy other vessels al
no infreQuent Intervals and the damage resulting
to traffic has amounted to more than $4,000 IN ths
last year.
At the completion Of the work In the East River
the Brooklyn Ferry Company Will establish a new
line OF ferries from Broadway, Brooklyn. 70 East
Forty-second-st-. Manhattan Two large dounls
deckers are being built for this service each capa
BILE of carrying fifteen hundred passengers one
has been named the John Englis, after the genera
manager Of the company. and the other the HART
B. Hollins after the vice-prastdent.