Engineering Wonders of the World
Volume I
År: 1945
Serie: Engineering Wonders of the World
Sider: 448
UDK: 600 Eng -gl.
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276 ENGINEERING WONDERS OF THE WORLD.
tremendously expensive. The cost is esti-
mated at $50,000,000 at least—more than the
cost of tho four East River bridges put to-
gether. In order to pay interest on this sum,
the structure would have to earn a profit of
two or three million dollars per year, and the
prospect for such an earning power is any-
thing but rosy.
This ambitious but unpromising project
fittingly concludes our survey of New York’s
bridges, for it emphasizes well the potency of
the financial factor in engineering work.
Great bridges are always serious problems
for the engineer, yet in many cases the
constructive difficulties, formidable though
they be, are less serious than the problem of
finding money and making the undertaking
pay.
Fig. 31.—THE GREAT ARCH OF THE PROPOSED HENRY HUDSON
MEMORIAL BRIDGE, NEW YORK.
The span of 703 feet will be over 2J times as long as the next largest concrete
or masonry arch in existence. In the upper figure the black lines indicate tho
steel rods reinforcing the concrete of which the arch is mainly composed.
(By courtesy of the “Scientific American.")