The sun. [volume] (New York [N.Y.]) 1833-1916, 1914-01-25

burden Of fighting fleet
double the size OF the Ameri-
can navy. The breaking through re-
Gently OF the last stone barrier In the
path OF the great tunnel which is to
aid in furnishing this supply opened
the way for the waters to run from the
Catskill Mountains to the Flatbush ter
minal shaft, a distance, as the crow
flies, Of more than ninety miles. But
the actual straw through which New
York's citizens are to quar- has a total
length Of quite 1877 miles. 1t is plain
therefore that this aqueduct does some
lodging and diving as we'll as deal Of
burrOwing before 1t arrives here.
The construction Of the Catskill
water supply system. Of which this
aqueduct forms part has been in prog
ress about eight years. Credit for the
undertaking is due Mayor George d.
Mcclellan. 1t was his administration
that realized the importance Of pro-
viding an increased water supply to
meet the future needs OF the growing
city. and it was while he was In office
that the steps were taken which will
result next year in adding 500 200, 900
gallons day to New York's available
supply Of water. In view of this fact
some regret has been expressed that
he should not have been present the
other day to witness the blowing up
Of the last rock barrier in the aqueduct
the elimination Of the project started
in his sterm Of office
The authorities announce with justi-
fed pride that the new aqueduct forms
the largest and longest rock tunnel in
the world. The famous Simplon tun-
mel through the Alps Is shorter by a
third than the rock hewn passage just
finished beneath our feet. And yet how
little busy New Workers have realized
what has been going on far below the
street line for the past three years.
True, there have been shaft openings
here and there along the line from
which dirt and rock have been dumped
init waiting carts, but this gave to the
passerby little idea Of what was taking
place underground from the Harlem
River southwark. Every twenty four
hours at least twelve tons of dynamite
was exploded under the streets, an av-
erage OF half "a ton at each of the
twenty-four shafts, and while its force
was sufficient to break through the
primordal backbone upon which our
skyscrapers stand. still the reverbera-
tons seldom If ever reached people In
the light of day This Is not hard to
understand II it Is considered that the
glittering spire of the Woolworth tower
Is not 30 high above Broadway as the
tunnel beneath the East River is below
sea level.
There were good reasons for burrow-
Ing 1j2 feet below the tide, and the
same reason compelled the engineers
to go down more than 400 feet deeper
when crossing beneath the Hudson
River this side of Cornwall. The aim
was to get an envelope of absolutely
rigid rock that would withstand the
full pressure Of the head of water pour
Ing down from Ashokan up in the Cats
kills
When the water is finally turned
into the great system underneath the
city's foundation there will he sufficient
natural pressure to carry the supply
unaided up 10 the twentieth door Of
tall buildings, where to-day the head
Is equal only to raising the water to
the seventh. To iriprison this force
enectually 1t was necessary to tunnel
through solid rock and TO make certain
Of an abundance of rock above the
aqueduct in order that there could be
no chance Of the pent up waters break
ing away surfaceward.
From the Ashokan Reservoir to the
level of the Hudson River is a drop OF
five hundred feet. one hundred feet
below the tide lay the river bottom
at the deepest point where the line was
to cross. To lay n tunnel less than
fifty feet below that would not do with
only clay and silt above for a cover
ing. Now one hundred and fifty feet
below water level is about the physical
limit Of the sandhog. and it would have
been for the pressure worker to bore
the hole for an aqueduCt at that depth
below the surface Of the Hudson.