New-York tribune., 1872-07-29
IMPORTANT ENTERPRISES.
PROGRESS OF TEE LEADING LOCAL
IMPROV VEMENTS.
THE EAST RIVER BRIDGE


Sefore Winter The New-Yoyb pier, although scarcely
noticeable frou the Fulton Ferry boats, is about seven
feet above high water mark, but Is not Nh"S " Oo
finished before pext year, thoueh tno broohSh .o"o'S
will be ready mpch The next WORK VII pe tne
anchor piers on the completion 81 which the ease wires
will he LAID Tls work will require about three years
The New-York caisson was completed and was towed
into position last September BY The end OF October ten
additional courses Of timber had been placed upon IT,
and nv the middle Of December efficient masonry had
been hult 10 sink it so that il stood on the bot
tom at high tide, when filed with cir.
coerdAm had been previously built around it to pro-
tect it from the swift tide currents and work within IL
was at begun. For the purpose of keeping the
casson filed with air day aud night thirteen pump en-
Eines were used The site of the caissOn had been
dumping ground and covered with animal matter
below which wore sand, gravel, quicksand, and rock
She anchor piers are those in which the cables,
after passing the towers to be secured
The distance between the towers is 1900 feet and, be-
side the span. there VIII be minor spans at either
end, $40 feet IN length. These will be mostly the
land. The New-YOrk anchor pier will be just north of
DOverst, between Water and Cherry-sts. and the
Brooklyn per will be in Jamesst, just above Garrison
ct. From these there will be a viaduct Of arch and
truss work ending at Chatham st. in NewYOrk, and
sands-st in Brooklyn The breadth of the bridge will
be IS feet and that Of the viaducts 100. Much Of the
property beneath the vaducts VIII be purchased by the
company, and will be used as sites for stOrehOuses
The three towers the river piers will be arched over
so as to make a continuous wall The keystOnes Of the
arches viii be feet above the level Of the bridge The
total hight Of the towers above high water Will be 2S
feet over the towers four cables 6 inches in diameter,
made of steel wires, sixth Of inch thick and bound
together with wire, Will extend. The weight Of the
bridge between the piers, including the cables will be
S9O0 The maximum Of weight the bridge will sup
port viii be l1G4 The pressure the masonry will
be 26 tuns per square brick will sustain 81
per square granite about OoO that the
towers will be perfectly safe The land spans viii bal
the river span the pressure on the towers being
therefore, vertical and not lateral The cables Will run
iron rollers at the top OF the towers In order that
they may yield a trihe, should unusual pressure be
placed any part Although the charter only requires
the bridge be 1876 feet above high water IL will be 3S
feet two inches It, Variations Of temperature will
give aud fail Of three feet and two inches; at Its
lowest the bridge will be five feet above the required
hight beneath which al ordinary shipping pass.
The bridge viii be divided into hye spans the two
for driving, the within those for horse
ears and the central for ootpasengers The latter
span viii be elevated above the rest one Of the driving
spans will be for fast driving, and the other FOR trucks
Teams going westward vii. lake the north span and
those sQng eastward the south span. The total length
of the spans and the vaducts Will be 5s62 feet The
horse cars will be abe 10 run in three minutes from
Chathamst to sands-st ( eal 1...
THE UNDERGROUND RAILROAD.
Isaac IL. BuckhOut, formerly Superintendent
OF the Harlem Railroad, and Chief Engineer oI
the new Underground Railway, has furnished the 'oI
lowing particulars of the progress OF that WORK;
The route decided upon, aud within the next
two omonths the ground viii be broken simultaneously at
intervals Of about half mile each along the entire ne
The work Will be prosecuted with ygor anQ wiLan Two
years from the present time passengers will be able to
avail themselves Of rapid transit within the thckest
portion Of the city some Of the depotsites have been
secured and they viii probably be about seven in num-
ber The dimensions Of the depOts will depend on
and hus he |
about eight by twelve feet above the surface The ar
rangements the depot for convenience and safety TO
passengers are complete possible. On entering the
passenger will descend the track level and when at
the foot Of the stairway will find himself on platform
between the two tracks, which dyelge near the stations
and afford space for platform sufficient TO accommodate
large number OF passengers Thus passengers gong IN
either direction will not need 10 cross the tIaeSs- ~
ondst will by switches at Ffty-sxth-st where
present Harlem tracks Will run 10 the Grand Central De
pot as al present while the grade OF tne RAPID adns 1
pot. The central depot will be entirely independent O
lie downtown road which will follow the course of
FOurb-aVe and the BOwery Pelst and thence TO the
CITY Hall Park Here Will be built large undergTS9nd
depot depots along the line will terminate at Fifty
nnthst, wleEe there viii be age one IVF tAe ACCOM-
mediation Of visitors 10 Central Pax. .,.
The road will be graded TO run beneath the sur
face throughQp the entire length and no vadHe1 MI p
necess 5t any point. The lowest point on & the line y
hgn tide On the Bowery, after leaving the rive POINTS
the lowest point o. Gr2nSs road dhe p6fE M TdT budg
f fS road temporary BRIGGS w be built at the cross
@ Of The e PC 5annS # f@st + snS S5 IL y many many 6a
passengers will he Transferred at the junction OF the
rapid transit aud the Harlem road The trains, now
ever winch leave the City Hal PARK depot will be
T6agh trains transfer taking place AT any part OF
the route Tie will be constructed with doors on
either side, the seats being athwTt by tms arrange
nent little time will be lost IN the entrance ana ext
OF passengers The entire distance from the Junction az
Fiy-sixthst to City Hall Park Is about four miles ana
The TupUiDg tlQe including Six sIoppages VIII DC oy
From a. Thirteenth to Nneeenth-st. and from Thirty
second 10 E1ftysxh-st solid masses OF fOck through
i.h
viii vary with the surface. From city Han 10 Saud4s'
lhe Grade viii be about sc feet TO the mile
EXCAVATIONS AT HE'LL GATE.
The strait into which Long Island Sound,
At its western end is not especially dangerous
n the East River reached, where the tides OF tue
Sound and bay meet and produce swift and irregular
surrens These are naturally strongest on the inner or
toth side of the curve where they meet and iust at
this point ledge of rock-bnoEn Haletts Point
u ont Of the low meadow land and projects 200 or 800
f INTO the seehing waters Vessels in passing through
e channel seek avoid this rock, and N the attempt
are in peril OF striking several others to the north and
vest. and as number Of these rocks are below the
surface the passage is all the more hazardy'
The task Of engineers has been to remove the sub
ereed parts OF the Hallets Point ledge and the small
i,onds and hidden rocks The method at Haletts Point
-, o,ect the ledge from high tides by cOilerdam;
10 excavate basin 80 OF 40 eeJ deep 10 run ouV unes
from the bottom OF tins Da5.hi 10 cur away to io &
tween fbese tunnels 10 leave only series OF oCh
,sr Tor the mass above 70 rest upOn 10 pace htlo
piala ianeatb these pillars; TO let In the water, so
ESeoi tr Lrfter execution; TO explode the nitro
,lyceyiue nv electricity; aud 10 remove me HdtHc41S
eu nj rock inc edge Of which vessels can approach
H"., ~ Vl 6e left The submerged rocks 10 the
nnrtb and the west VIII De dlled Dy MaehlnVly on On
sces and uitrOg gyceTne, which s hedS SieI uah ~ate
D. In n ke "A stone will be- placed IN the hOles py
,.rcrs and bc exploded by elcculcltN' III INC Cas VI
i0Gu t hvv e6de and which is now used magazine
Engineers have decided whether IL VIII D' Do''' "
tunnel ,r 0T 70 Which IS under the United States Army En-