From this reservoir it is proposed to conduct the water, through the 5th avenue, to the distributing reservoir on Murray Hill, by iron pipes. In following the line of aqueduct as above described, its grade will, in several places, be above the present surface of the ground, and from 102d to 95th street inclusive, in order to accommodate the carriageway and sidewalks, archways must be erected over the streets, and the aqueduct carried on a stone embankment of from 33 to 48 feet in height ;

and in passing through the 5th avenue with the iron pipes to the distributing reservoir, a portion of the carriageway must be graded, in order that the pipes may be sunk to a proper depth below the surface of the street not to be out of the reach of repairs, should any be at any time required, nor so near the surface as to be exposed to the action of frost.

The Commissioners submitted an estimate to your honorable body in their report of the 3d of July last, of the probable cost of completing the first and second divisions of the aqueduct, and promised to report an estimate of the total amount that would be required to complete the whole project, including the receiving reservoir between the 6th and 7th avenues and 79th and 86th streets, and the distributing reservoir on Murray Hill, in order that authority might be obtained from the Legislature to raise the additional funds required. The chief engineer has, accordingly, at the request of the Commissioners, furnished them with his views on the subject, so far as they relate to the operations of his department of the works, including the most substantial and economical mode of construction, with the probable expense of such construction and the Commissioners have ;