[Footnote 23: The location and strength of Fort Stirling, the citadel, and the other works on Long Island, are noted more in detail further along in this chapter.] The East River thus provided for, attention was paid to the city and the North River side. Lee examined Fort George and the Grand Battery, but gave it as his opinion that neither of them could be held under the concentrated fire of large ships. He advised, accordingly, that the northern face of the fort be torn down, and a traverse built across Broadway above it at the Bowling Green, from which the interior of the work could be raked, should the enemy attempt to land and hold it. As the North River was "so extremely wide and deep," the general regarded the obstruction of its passage to the ships as out of the question. Batteries, however, could be erected at various points along the west side where it rose to a ridge, and the power of the ships to injure the town very considerably diminished. All the streets leading up from the water were ordered to be barricaded to prevent the enemy from coming up on the flanks; forts were to be erected on Jones', Bayard's, and Lispenard's hills, north of the town, covering the approach by land from that direction; the roads obstructed to artillery; and redoubts, redans, and fleches thrown up at defensible points throughout the entire island, as far as King's Bridge.[24] "I must observe," said Lee to the Committee of Safety, "that New York, from its circumstances, can with difficulty be made a regular tenable fortification; but it may be made a most advantageous field of battle--so advantageous, indeed, that, if our people behave with common spirit, and the commanders are men of discretion, it must cost the enemy many thousands of men to get possession of it." [Footnote 24: "_Feb. 23d, 1776._--... General Lee is taking every necessary step to fortify and defend this city. The men-of-war are gone out of our harbor; the Phoenix is at the Hook; the Asia lays near Beedlow's Island; so that we are now in a state of perfect peace and security, was it not for our apprehensions of future danger. To see the vast number of houses shut up, one would think the city almost evacuated. Women and children are scarcely to be seen in the streets. Troops are daily coming in; they break open and quarter themselves in any houses they find shut up. Necessity knows no law."--_Letter from F. Rhinelander. "Life of Peter Van Schaack._"]