to in the Report of the Commissioners, should be adopted, as submitted to, and approved by, the electors of the City and County of New York. Adopted by the Board of Assistants, July 9, 1838. The progress made during this year was great. The whole remaining line in West- chester County, comprising the third division, and six sections of the fourth, were put under contract, at prices lower than those of the preceding year, and with great competi- tion in the bids. The necessary maps of the land required on the island of New York, C R O T O N A a U E D U G'T. 157 amounting to about 26 acres, were completed, and negotiations were entered into by the Commissioners, for the purchase. Four blocks of the land required for the receiving reservoir, containing about 4f acres each, were obtained by purchase, and application was made to the Chancellor, for the ap- pointment of appraisers, on whose award the remaining lands might be taken. A circular was also addressed to the chief iron founders in the United States and Great Britain, inviting proposals for the iron pipes that would be required for syphons, and for connecting the receiving, with the distributing, reservoir. These pipes, for the most part, were to be 3 feet in diameter, and others 30 inches, varying in thickness, from one to one inch and a quarter each. The whole weight was estimated at from 4 to 5000 tons. This timely notification was given, to the end that it might be ascertained, whe- ther it was best under all the circumstances of the case, to import these pipes, or obtain them at home. In order to keep the progress of the work before the reader's eye, we copy from the Commissioner's Report of July, 1838, the statement of what had been accomplished since the previous report. The work performed during the winter consisted, principally, of excavation of earth and rock, in tunnelling, and in quarrying stone, and preparing them for use in the construc- tion of the culverts, bridges, and other erections connected with the aqueduct, which has greatly facilitated the spring operations. But, in order that some idea may be formed of the progress of the work, we beg leave to present the following statement, embracing the principal operations on the line ; such as the length of aqueduct completed, the number and extent of tunnel excavation, the number and capacity of the culverts erected, &c. : 1st. AGIUEDUCT. The whole length of aqueduct, arched and complete, was, on the 25th of June last, 10,280 feet, or about two miles in length. 2d. SIDE WALL. The length of the side wall of the aqueduct, ready to receive the arch, exclusive of that already arched, was 18.376 feet, or about three and a half miles in length. 3d. CULVERTS. There are twenty-two culverts completed and in use, discharging the water from the several creeks and runs, some of them of considerable magnitude ; and their aggregate length is 1825 feet. The number partly finished was seven, and their length is 578 feet. Seven of these culverts measure from 100 to 148 feet in length ; seven of them from 80 to 96 feet, and thirteen of them from 50 to 72 feet. Nine of them are large, measuring from six to ten feet span, eight of them from three to four feet span ; and the remainder, from one and a half to two feet. 4th. TUNNELS. Three of the tunnels have been perforated through the solid rock, from one end to the other, in the aggregate 670 feet in length. One on section twenty, 335 feet ; one on section fifteen, 165 feet ; and one on section thirty, 170 feet in length. There are also five tunnels, partly finished, measuring, in the aggregate, 610 feet, excava- ted. In a long tunnel on section fifteen, there have been excavated through the solid rock, 40 158 MEMOIROFTHE 360 feet ; and another on section sixteen, 200 feet ; the other three, from 10 to 25 feet ; making a total of tunnel excavation of 1280 feet in length. 5th. FOUNDATION AND PROTECTION WALL. The quantity of foundation wall laid, amounted to 28,000 cubic yards, and of protection wall, 13.160 cubic yards. This is but a very brief sketch of the work which has been performed, and is con- fined altogether to the operations on the first and second divisions, exclusive of the large amount of excavation in rock and earth on a line of thirty-three miles in length, nearly the whole of which has been completed, together with a large amount of building mate- rials prepared. The contractors on the sections lately placed under contract, comprising the whole of the THIRD and a