The semi-weekly messenger. [volume] (Wilmington, N.C.) 1897-1908, 1906-09-11
PENNSYLVANIA TUNNELS
NOW NEARING COMPLETION
sections of IN First Of the Hugh Hud-
son River Tubes VIII Meet About
September 18th

At i O'Clock Saturday night III work
on the Pennsylvania tunnels under
North River ceased. Tie engineers on
! Monday began 3 thorough rev. " 0
the ent!r, work. Every meaSu-vm,at
will be verified even down t. me
thousandth Of IN inch. Fv, or x
days will D devoted IL This NO f.,
after which the boring OF The Z. orm us
tubes will b., resumed. and il ! expeC-
ed hat about September IS. he tunnel
shields which have been pushing f1r-
ward from I'll" TWO sides # the river
will meet. The Pennsylvania rail ca
Will then have for the first time .
means OF reaching Nanha.,an Island
entirely Y e land This event VIII SO
mark he beginning OF the compile 7
Of what is probably the bnlde>t ea-in-
erjng feat n history.
When work was stopped last uL--t
the shields We-a l25 fe-t apart, The
examination Of The text few days VII
determine how accurate We're the pre-
liminary surveys and preparations, that
extended over a year. 1t Is belic~cd
by those N charge IF the work that the
grade. level. and alignment Of bo h
these huge tubes will be found to rest
within an inch of where they were
supposed TO be, If there is even ="
slight a variation as this it viii be & Z
rected 50 that when h shields finally
meet under the middle Of the ritter.
they will telescope aS accurately as
the sliding of n tub within anOth"T.
In order 10 make this checking as
accurate as possible the south tunnal
from the Jersey shore has been run
ahead Of its mate, 50 hat now II oyr~-
laps the northern tunnel starting from
the New York shore Pipes will hs
dripen across the fourteen feet that
separate the tubes and angles run
which will show how nearly the tr-
gineers have kept 10 the line and ele~
walton planned.
This thorough review" upon which
SO much depends will be under the
personal direction Of Charles VI. Jacobs
chief engineer, and James FOrgie, prl1-
cipal assistant engineer. Of the North
river tunnel work. Tie most improved
instruments science has produced Will
be utilized. The entire distance of
both tunnels. 1000 feet between the
shafts or each side of the river, viii lie
measured and re-measured. No chances
Of amy kind will be taken.
Some idea Of the methods pursued
in work Of this character may lie gath
cred from the fact that during the
progress of this work, measurements
Of the most exact character have been
taken every day and night, for the
work has gone on continuously. Every
variation in temperature has ba2n
carefully regarded. In making rleas
urementS and alignments, if an mo
Of as much a. onethousandth of ItfOOt
was found, the work was re-survcyCd.
! Charles N. Jacobs, the chief engineer
Of this part of the work. and who mas
had to do with the building Of more
tunnels probably than any other living
man, said today
I'VE ave now reached a stage where
all our fine preliminary instrumental
work must prove its accuracy. Her
| we have two enormous steel tubes Of
tWenty-thTee feet in diameter driven
| for 5000 feet under water and vet eA-
| pected 10 join as accurately as the SCI
| lions of Il bridge which can b. crntin1-
| ally measured with regard 10 their
| related parts. We feel confdtlt that
| our work will be 4 success. Nsverthe-
| less, ii is only when the actual fact
Is proved that We can heave q sigh Of
! relief and be refreshed [ con inue our
labors toward a completion OF our
| task