Omaha daily bee. (Omaha [Neb.]) 187?-1922, 1906-09-17

Railroad Tunnel Tubes Under North
River Formally Joined.

Railroad Tunnel Tubes Under North
River Formally Joined.
The tunnel tubes built by the Penn
sylvania Railroad company under the Hud-
son river were Joined last week. The
event was suitably observed by of1cials
in charge, the workmen and a few guests
A more elaborate celebration IL set for
September q, when the high oficers OF the
railroad will inspect the work and walk
under the river from Jersey City to the
site OF the company's terminals in New
York City.
An achievement in tunnel building OF
the first magnitude" is the press verdict
on an undertaking which will give the
Pennsylvania company direct entrance to
New York City. The company's plans
also embrace a like tunnel under East
river, connecting the companys Long
Island lines with the main terminal in New
York. The completed tunnels and ter
minals will cost So,0oo,ocO. Electricity will
be the motive power.
The North River division OF the Pennsyl-
vania tunnel improvements extends from
the terminal now under construction in
New York by two main line tracks under
the river and Bergen hill to the Hscken-
sack meadows. west Of the Palisades. II
has total length of IL, 100 feet.
From the time. that the Pennsylvania
railroad announced its plan of tunnellng
under North river FIVE years ago the
building of the tubes has been one con-
tnued series Of engineering triumphs
Among other things the rapidity OF the
work has been unprecedented. and the rec
ord-twelve and a half feet In eight hours
Fat 20 an1 at.
for some time.
New York side April IS, 1909, and on the
Jersey side September /, 1904 II is expected
that the shields In the south tube will be
entirely finished In two years.
The rapidity of the construction work is
all the more remarkable because Of the I'M
forseen obstacles that were encountered as
the work progressed. The divergent rocks
and soil formations through which the tun-
mel had to be carried were responsible for
much unlocked for trouble, together with
the dangers encountered through the pier
cling of gas pockets and other natural hin
ORANGES.
The tunnel consists OF two enormous steel
tubes twenty-three feet each in diameter
These will be reinforced with solid con-
crete work to give the bores a strength and
endurance that should make them last for
ages.
The vertical shaft on the Manhattan side,
which Ii located at Eleventh avenue and
Thirty-second street, was started on June
IL, 1908, and finished on December II of the
same year. Work on the Jersey shaft
which is near the Erie railroad yards In
Weehawken, was begun on June Is, 1903, and
was finished on September /. 1904. Work
on the tunnel proper~that Is on the two
tubes that now meet under the river-was
begun on the New York side on April 49,
1904, and on the Jersey side September l.
1904. The two tube sections of the north
tunnel met on September IL, and It is ex-
pected that the shields Of the south tube
will meet about October I. The structure
will be entirely finished and ready for rail-
road traffic in two years.
In the construction of a subaqueous tun-
mel the design of a shield is by far the most
important consideration. The shield de-
signed by Mr.. Jacobs and used by the con-
tractors, has a hood extending two feet be-
yond the cutting edge. The main body Of
the shield is fifteen feet long, the length
over the hood being eighteen feet The OBJ
ject of the designer was to make the back
and the face of the shield as acces-
sible. one from the other as possible and at
the same time to have a means of shutting
of promptly a rush of water from the face
A pivotted segmental door was used and
proved to be we'll adapted for the work, CIV
ing ample room for men to stand and shovel
at the same time, and be absolutely clear
of any work overhead and clear Of the
sweep of the erector, the immense arm
which picks up ring plates and puts them
in place.
The shield has nine doors two on the top
platform, four on the middle and three on
the bottom. 1t weighs 1874 tons.
The actual building of the tubes was prac-
tically put in the hands of Charles NJ
Jacobs, who has probably built more sub
aqueous tunnels than any other man in
the world. He was made chief engineer.
The chief assistant engineer is James
Forgie. who assisted the engineer, Great
head, in the construction OF the Waterloo
and City railway tunnel under the River
Thames In England in 1894 Mr.. Jacobs de-
signed the type of shield that is used in
the North river work, and which enabled
the contractors to make such rapid prog
ress. Mr. Forgie designed the sliding plat
cavations ahead of the shield. This, too,
was a great advantage to the contractor,
and added to the general success of the
work.
The franchise obtained by the Pennsyl.
vania railroad from New York City stip-
ulates. although It is perpetual, that there
shall be a renewal of charges every twenty
1--WE years As wow fixed the company is to
pay to the city 80 cents for every linear
foot OF track for the first ten years and 81
for every foot In the next fifteen years, in
the Borough Of Manhattan. The rates are
to be one-half OF these sums In the Bor-
ough of Queens. The total trackage will
amount to more than 10000 feet in this
borough alone. Altogether. 1t is estimated
the city will receive from the company In
the frst twenty-five yearsmore than s24IS,-
co.,
The tube itself, which is twenty-three
feet in diameter, consists OF a series OF cast
iron rings, and the installation OF every
ling meant a progress OF two and one-hat