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Old
photos of the city
of New York ,
bridges under construction
The
old times - Los viejos tiempos | Español : Viejas fotos de Nueva York
, puentes en construcción | Old
times photos : City of New York , Denver , New Haven , Salt
Lake City | Other old times
photos :elevators around the world
The city of
New York and its suburbs was in communication in the beginning
of the XX Century by the four major East River crossings : the
suspension bridges of Brooklyn, Williamsburg and Manhattan, and
the cantilever bridge of Queesboro . The first was open to the
traffic in 1870; the second, in 1903, and the others, in 1909.
Let's take a journey to the past in the following photos .
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Provisional steel
armor used to construct a section of the Queensboro bridge .
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| The Queensboro
bridge or Blackwell’s Island Bridge , is located at three miles
of the Brooklyn bridge ; it crosses the East River , where the waters
are divided into two deep channels subject to the tide at each side
of the island. During the construction , two main stirrups in this
island, one on each side, and two more in the far banks have been
elevated, with another stirrup that advances within the water. The
arcs on the channels respectively have 360 and 300 meters in length.
The overall length of the bridge is of 2,362 meters. The construction
of this bridge took eight years , and the cost, including with the
price of the land, was about 17,500,000 dollars. It has consumed 70,000
tons of steel and 76,000 cubic meters of masonry work. The arms of
the rigid counterbalance in the enormous western arc measure 183 meters
and weigh 8,000 tons each one. These arms were constructed at 41 meters
over the surface of the water; the portion of armor mounted, from
the stirrups of the island, covers on this one a length of 192 meters.
Thus , it forms a continuous superior structure of 521 meters in length
from center to center of the river channels that weighs 25,000 tons. |
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The same section, with the separated
provisional armor, and the counterbalance arms finished.
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There
was a great number of difficulties found in the project . During
the summer the thermometer frequently reached the 100 Fahrenheit
(37.7 °C), and in winter it descended near 0° F. (17, 7
°C), and furious hurricanes and snow storms swept the river;
steel pieces of 30.50 meters in length and of 60 tons of weight
were raised to heights between 30 and 91 meters over the active
traffic working on earth and the river, but no damage got to take
place neither to the people nor to the stuff . The part of bridge
constructed on the island was a type of provisional steel armor,
of 1,700 tons of weight , and that required as much work as the
construction of many railroad bridges. This construction was carried
out by means of moving cranes, and on this armor gins were elevated,
with a weight of 65 tons, to take care of the same construction
of the bridge . In addition there were other two movable cranes
of 38 meters that weighed 625 tons each one. All the structures
of the bridge were previously assembled in factories located at
161 kilometers of distance, and in communication with the work by
railroad and the aquatic route. Some of the pieces weighed 78 tons.
In addition to the rivets produced in the factories, 750,000 were
made in the very workplace .
Twelve shifts , of
four men each one, could apply thousands of rivets every day, using
hand hammers that worked by means of compressed air at a speed of
1800 blows per minute. Wires, instead of bars, for the suspension
bridges, were used for the first time by J. A. Roebling in Niagara
1855, for a bridge with a length of 252.50 meters. His son, W. A.
Roebling finished, in 1883, the Brooklyn bridge of 486.33 meters
long . It was the longest suspension bridge of its time; steel wire
was used for the cables . Each one of four suspension cables of
the Niagara bridge contained 3,640 wires. In 1877 the cables were
carefully inspected , and they were practically without any defect
after twenty years of operation. In the Brooklyn bridge the cables
are of 387 millimeters of diameter and are composed of an even greater
amount of 5,296 wires. |
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Photo of the Manhattan
bridge in stage of construction, picture taken from above.
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| The Manhattan
bridge constitutes another communication channel between
New York and Brooklyn, being the forth to be destined to that
service in the beginnings of the XX Century. In certain concepts
it is still more remarkable that the Brooklyn and Williamsburg
bridges. Considering its constructive characteristics , we can
describe that its span , including approaches, is of 2,089.50
meters. The central arc measures 448 meters and both arcs of
both margins measure 221 meters each one. The weight is supported
by four enormous steel cables of a diameter of 585 millimeters,
constituted each one of them by 9,472 wires. This bridge (considering
as it was conceived in its original project ) is of double floor
type ; by the lower floor passes a highway of 10.67 meters wide,
with two sidewalks of 4 meters wide for pedestrians and four
lanes for fast vehicles . The upper floor has to two routes
for electrical street cars and one road of 7.16 meters wide
. The width of the bridge reaches 37.33 meters, and the height
over the surface of the channel, that there has 122 meters wide
, is of 41 meters. The foundations of the towers that support
the cables are constructed in the bed of the river on great
wood drawers, submerged at a depth of 28 meters under the water
in the high tide. |
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Photo
of the Manhattan bridge in stage of construction, picture taken
from the bottom .
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Moving crane of 600 tons placing
in position the last section of the construction of the Manhattan
bridge |
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Old photo of the railroad Hell Gate
Bridge in New York, with a span of 310 meters and a weight of 28,000
tons
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