But, before Greene could cross the Delaware, Lord Cornwallis approached with an army rendered more powerful than had been expected by the junction of the reinforcement from New York; and fort Mercer was evacuated.
A few of the smaller galleys escaped up the river, and the others were burnt by their crews.
Washington still hoped to recover much of what had been lost.

A victory would restore the Jersey shore, and this object was deemed so important, that General Greene's instructions indicated the expectation that he would be in a condition to fight Lord Cornwallis.
That judicious officer feared the reproach of avoiding an action less than the just censure of sacrificing the real interests of his country by engaging the enemy on disadvantageous terms.

The numbers of the British exceeded his, even counting his militia as regulars; and he determined to wait for Glover's brigade, which was marching from the north.

Before its arrival, Lord Cornwallis took post on Gloucester Point, a point of land making deep into the Delaware, which was entirely under cover of the guns of the ships, from which place he was embarking his baggage and the provisions he had collected for Philadelphia.[73] [Footnote 73: While Lord Cornwallis lay on Gloucester Point, about one hundred and fifty men of Morgan's rifle corps under Lieutenant Colonel Butler, and an equal number of militia, the whole under the Marquis de la Fayette, who still served as a volunteer, attacked a picket consisting of about three hundred men, and drove them with the loss of twenty or thirty killed, and a greater number wounded, quite into their camp; after which the Americans retired without being pursued.] Believing that Lord Cornwallis would immediately follow the magazines he had collected, and that the purpose of Sir William Howe was, with his united forces, to attack the American army while divided, General Washington ordered Greene to recross the Delaware, and join the army.
[Sidenote: The enemy succeeds in opening a free communication with his fleet.] Thus after one continued struggle of more than six weeks, in which the continental troops displayed great military virtues, the army in Philadelphia secured itself in the possession of that city, by opening a free communication with the fleet.[74] [Footnote 74: While these transactions were passing on the Delaware, General Dickinson projected another expedition against the post on Staten Island.

He collected about two thousand men, and requested General Putnam to make a diversion on the side of Kingsbridge, in order to prevent a reinforcement from New York.
Knowing that success depended on secrecy, he had concealed his object even from his field-officers, until eight of the night in which it was to be executed.