dam, of 14 feet span, and 125 feet in length. The foundation wall at this place is 50 feet in height to grade, and 62 feet to the top filling of the aqueduct. 6th. An aqueduct bridge over the railroad at Harvey's marble quarry, of 16 feet span, and 10 feet in height. 7th. An archway over the road at Saw Mill River, of 16 feet span, and 14 feet in height. 8th. The large double culvert on Saw Mill River, with arches of 25 feet span each and 82 feet in length. The river is 42 feet below grade, and to the top of the aqueduct, 56 feet. The two last structures are connected, the aqueduct passing over both of them, in its course to the city These important pieces of workmanship, are composed of the first quality of building stone, hammer dressed, and well bedded together. They are a credit to the skill of the mechanic, as well as to the architect, and are now nearly complete, the arches of all of them being closed, except at Sing Sing Kill, and Saw Mill River, both of which will be closed before the termination of the present working season. The Corporation, on their part, continued preparations for the distribution of the water. The following resolution, adopted by both Boards, was approved by the Mayor on the 17th of April : 44 174 MEMOIR OF THE Resolved, That a line of water pipes be laid through Christopher-street, from Hud- son-street to Sixth avenue ; also, through Clarkson-street, from Hudson to Varick-street, through Varick to Hammersley, through Hammersley to intersect with pipes already laid in Houston-street, also through Houston-street from Hudson-street to Greenwich-lane, and through Greenwich-lane to the Sixth avenue, and that the Water Purveyor be authorised, under the direction of the Joint Committee on Fire and Water, to advertise for estimates for the necessary pipes and fixtures, to lay the same agreeably to the Water Commissiorir ers' map. In order, moreover, to comfirm confidence in stocks issued for the Water Stock, they adopted this resolution in June : EXTRACT OF A LAW OF THE CORPORATION, ENTITLED " A LAW PROVIDING FOR THE REDEMPTION OF THE CITY STOCK." § 2. All revenue to be received for water, to be procured by the works for supplying the city of New York with pure and wholesome water, and furnished to the inhabitants of said city, is especially pledged and appropriated as a Sinking Fund towards .the redemption of " The Water Stock of the City of New York." Approved by the Mayor, June 19, 1839. During the next six months, until 31st December, the contractors seem to have pressed forward their work with undiminished zeal, having in their employment, on an average, from 3000 to 4000 men. The expenditures during the year, reached the great amount of $2,300,438, and at the close of it the following results appeared : 1st. The Aqueduct. — The whole length of aqueduct, arched complete, is 137,630 feet, running measure, or about 26 miles. That complete on the 1st of July last, as per our semi-annual report of that date, was 77,587 feet, or about 14 and two-thirds miles. The increase in this part of the work, since our last report, is 60,043 feet, or about eleven and one-third miles. 2d. Culverts.. — There are now 114 culverts complete and in use, for discharging the water of the several streams on which they are erected. Their length, in the aggregate, is 7542 feet. The number completed at our last report was 92, and their length 6240 feet. There is therefore an increase of twenty-two culverts, since the first of July last. 3d. Tunnels. — The number of tunnels excavated through their whole length, is seven, and they are, in the aggregate, 2068 feet in length. There were five completed at our last report, of 1195 feet in length, which shows an increase of two tunnels com- pleted, of 873 feet in length. There are besides the above, nine tunnels in the progress of completion, that have been excavated in the aggregate, 2133 feet, making the total of tunnelling up to the 25th of December, 4201 feet, alnd of masonry on the aqueduct, with- in the tunnels, 2476 feet, being an increase, during the last six months, of 1964 feet in length. 4th. Foundation and Protection Wall — The foundation wall now laid, amounts CROTON AQ.UEDUCT. 175 to 115,210 cubic yards, and the protection wall to 114,384, making a total of 229,594 cubic yards of dry wall, which shows an increase, during the last six months, of 63,344 cubic yards of wall. 5th. Ventilators and Waste Weirs, — There are 24 of these necessary structures now finished complete. A large portion of them are intended as ventilators to discharge