The side walls of the bridge were raised at the same time and the pipes were covered with a brick arch, on the top of which is a promenade, from which a view up and down the Harlem is obtained, which is one of the most attractive in the vicinity of New York. This improvement is commemorated by a bronze tablet let into the walls of the gate-houses on both the New York and Westchester sides of the river, reading as follows :

' The Improvement of this bridge by adding the large pipe, raising of the side walls and covering the whole work with an arch was commenced October, 1860. The new pipe was put in operation December, 1861. The masonry completed in 18C3.

" Oo(<«i Aii<iedticl Board, " Thoma-s Stephens, President Commissioner ; Thomas 15. Tappen, Assistiint Commissioner to Dec. 4, 18G2 ; Alfreil W. Craven, Commissioner and Engineer-in-chief; Engineers: George S. Greene, Engineer in-charge to Feby. 31", 1862; Wni. V. Dearborn, Engineer-in-charge from Fehj. 1", 1862; Contractors, Thomas F. Rowland, for the pipe; .1. P. Cnmmings, for the masonry."

The Central Bridge or Macomu's Dam. -- In 1800 the mayor, aldermen and commonalty ceded to Alexander McComb and his heirs and assigns, " All that certain piece or parcell of land covered with water situated in the 7th Ward (now 12th Ward) of the city beginning at the West side of Kingsbridge at low water mark on the north side of the river, creek or run of water called Spuyten Duy vil ; thence running along the creek westerly at low water mark one hundred feet; thence crossing the creek to a place at low water mark one hundred feet from Kingsbridge; thence along the creek easterly at low water mark to Kingsbridge and thence along the West side of the bridge to the place of beginning.'' A passage-way fifteen feet along the course of the creek was reserved to be kept clear, open and unincumbered, so that all small boats and craft might freely and without obstruction pass and repass the same, with a right on