HARLEM RIVER BRIDGE. The width of the river at the place where the aqueduct line crosses it, is 620 feet at ordinary high water mark as has been before stated, the shore on the southern side is a ;

bold rock rising from the water's edge, at an angle of about 30 degrees, to a height of 220 feet on the northern side, a strip of table land forms the shore, and extends back from the ;

river 400 feet to the foot of a rocky hill, which rises at an angle of about 20 degrees to a few feet above the level of the aqueduct the table-land is elevated about 30 feet above ;

the river the channel of the river to which the water is reduced at very low ebb tides, is ;

300 feet wide, and the greatest depth 16 feet each side of the channel the bed is a deep ;

mud, covered from three to four feet at ordinary flood tide next below the mud there is ;

a thin stratum of sand, and this is followed by a stratum of sand and large boulders intermixed below the stratum of boulders, or detached rock, there has been found in the cof- ;

fer dams for two piers, Nos. 8 and 9, a compact marble rock, and in the coffers for Nos. 7 and 10, a stratum of clay and sand, that is quite impervious to water, and affords a good medium for piling. The general plan of the bridge now in progress of construction, is as follows :