This massive structure, of which the dimensions and a description were given in the most beautiful and substantial of its kind in the last report, is supposed to be one of the world. The cut stone masonry of the overfall being now completed, with the exception of 15 or 20 feet at the southern end adjoining the waste culvert, a perfect idea can be formed of its finished appearance and this is well calculated to impress a spectator with ;

the belief that it is almost, if not entirely, indestructible by the elements, or time. Between the Croton Dam and the influent gate-house at Harlem River, the line of aqueduct was finished last season, and during the present season this gate-house has been nearly completed. The embankment in the Harlem River, which serves the double purpose of securing the cofferdams for the piers of the bridge, and forming a foundation for the temporary

194 MEMOIR OF THE water pipes, has been finished, and the pipes were laid upon it, and a connection formed between the two sides of the river early in June. To the lowest part of the large connecting pipe, a branch pipe was attached, and to this were fitted jets of various sizes and forms. This was done for the purpose of ascertaining by experiment, what form and size will be best suited for fountains, which may be erected in the public squares or other parts of the city, for convenience or ornament. The jet is generally allowed to play a few hours in the afternoon of every day, and the large volume which it throws to the height of 110 feet, is an object of much interest to those who visit this, at present, most interesting spot. HARLEM RIVER BRIDGE. The progress of this work, since our last report, has, owing to several causes, been slower than we expected.