The estimated cost of carrying the bridge up to its contemplated height, from the point or position in which it will be, on the 1st of July next, will amount to $596,779. After the water is introduced, by these temporary means, there will be no pressing necessity for the high bridge being erected faster than is convenient for the resources of the Corporation, and the economy of its construction, provided no objection should be urged against a reasonable interruption of the river navigation, by the persons interested therein, the value of which navigation is, at present, too small to be estimated.

Entertaining this view of this important subject, the Board of Water Commissioners have determined, and so instructed the contractors, that without further instructions from them, the Board of Commissioners, they, the contractors, are to do no work on the bridge, excepting such parts as may be necessary and directed by our engineers, to carry the water on the temporary plan across the river, and the erection of the piers of the bridge up to high water mark; and to accomplish this, will keep them busily employed until the 1st of January next. In giving these instructions, we considered we should best meet the views of our fellow-citizens and the Common Council. If we are mistaken in the wishes of the Common Council, we shall be glad to be informed of the same. Under this arrangement of the work, the whole amount required by this department to bring the water to Murray's Hill, will not differ materially from $650,000, which includes the settling up the demands for work already done on the several contracts not yet completed. CLENDENING VALLEY. The Common Council will recollect that we informed them, through their Committee, in July, 1840, thatwe proposed dispensing with the arched bridges contemplated to be made by the original plan, over 96th, 97th, and 101st streets.