Connecticut western news., 1873-05-23
The East River Bridge.
How it Is to be Anchored,

In New York the anchorage for the
 great East River Bridge will be situated
 in James street, between Front and Wa
 ter streets. In Brooklyn it will be situ
 ated at York street, near Mercein anC
 Prospect streets. Work has already
 been begun in the latter city, and is
 progressing with great rapidity. The
 ground upon which the masonry of the
 anchorage will be built is 125 feet long
 and l37 feet deep. The masonry, wher
 finished, will be 70 feetfrom the surface
 of the earth. The ground is excavated
 to the depth of 25 feet; and in order to
 prevent the caving-in of the soil and the
 underminingof the adjoining buildings,
 timber framework has been placed
 within the opening. Two longitudinal
 rows of piles were driven into the earth
 at the bottom of the excavation, and
 divided into three spaces, from 37 to 40
 feet between them, the piles being so placed as to make seven transverse di- visions of from 13 to 25 feet each.
 Heavy lines of bracing extend between the piles making 21 rectangular di- visions. It will be seen, therefore, that 40 feet long, and 13 by 37 feet deep.
 
 tlons to carry the stones to every part of the ground. In passing over the towers one of the cables extends over each end, and the other two over the middle, so that the anchor plates with which the cables will be connected by & chain will be correspondingly placed on either side of the rear of the anchorage, and in the middle.
 The anchor-plates are immense pieces of iron 2 feet deep oblong, 173 feet di- ameter in one direction and 16 feet di- ameter in the other. When placed upon the masonry they will resemble great spider lying upon his back with 16 legs extending in every direction. The legs are made with fianges faring so as to be firmly held by the masonry which will surround it. The plates are connected with the cables by two immense flat iron chains. The chains are each composed of ten links, each link being about 15 feet long, except the upper one, to which the cable will be attached. This will be 20 feet long. Each link is made up of nine fiat bars, the lower bars being seven inches wide and three inches thick, and the upper ones nine inches wide and three inches thick. These bars weigh about half a ton each, making the weight of each link four and half tons. The links are joined by heavy turned pins which pass through eyes placed in their extremities. Each chain will weigh about 50 tons, and the two chains which hold one end of each cable will contain about 100 tons of iron, so that in the Brooklyn anchorage alone the weight of the chains which connect the cables with the anchor plates will be4OO tons. The whole support of the bridge depends finally upon the anchorage, and the power of the anchorage consists in its weight or resistance to outside DOW CT but weight acts only in 0 vertical direction therefore the anchor plates which are the final ends of the cable chains, are placed at the near and low est end of the pile of masonry, with their upper surfaces horizontal. The plates have IS openings through their centers made to receive the nine bars which form the links of each of the two chains, and which are fastened by pins placed in the under side. Of course the first set Of links passing through the openings in the plates will be placed vertically, but from this point the chains begin to curve until they reach the point where the cables unite with them horizontally and 80 feet above the surface, thus describing the quadrant of a circle. That portion of the anchorage | the plates, along the whole | width of the rear, and 50 feet length wise from the plates, will be built of solid masonry.
 The remaining portion of the anchor age will consist of three walls running and supporting the | chains. A wall will be erected on each side and double wall in the center. After the chains have been placed in position upon the walls, masonry will be added {; the walls will be carried up and arched at the top to form the road bed of the viaduct, 99 feet above tide. The chains and plates will be forever hidden from view after they have been placed, and the final appearance of the anchorage when completed will be an immense piece of solid masonry.