Trenton struck alarm and dismay into the British, and Cornwallis, with seven thousand of the best troops, started from New York to redeem what had been lost. Leaving three regiments at Princeton, he pushed hotly after Washington, who fell back behind the Assunpink River, skirmishing heavily and successfully. When Cornwallis reached the river he found the American army drawn up on the other side awaiting him. An attack on the bridge was repulsed, and the prospect looked uninviting. Some officers urged an immediate assault; but night was falling, and Cornwallis, sure of the game, decided to wait till the morrow. He, too, forgot that he was facing an enemy who never overlooked a mistake, and never waited an hour. With quick decision Washington left his camp-fires burning on the river bank, and taking roundabout roads, which he had already reconnoitred, marched on to Princeton. By sunrise he was in the outskirts of the town. Mercer, detached with some three hundred men, fell in with Mawhood's regiment, and a sharp action ensued. Mercer was mortally wounded, and his men gave way just as the main army came upon the field. The British charged, and as the raw Pennsylvanian troops in the van wavered, Washington rode to the front, and reining his horse within thirty yards of the British, ordered his men to advance. The volleys of musketry left him unscathed, the men stood firm, the other divisions came rapidly into action, and the enemy gave way in all directions. The two other British regiments were driven through the town and routed. Had there been cavalry they would have been entirely cut off. As it was, they were completely broken, and in this short but bloody action they lost five hundred men in killed, wounded, and prisoners. It was too late to strike the magazines at Brunswick, as Washington had intended, and so he withdrew once more with his army to the high lands to rest and recruit. His work was done, however. The country, which had been supine, and even hostile, rose now, and the British were attacked, surprised, and cut off in all directions, until at last they were shut up in the immediate vicinity of New York. The tide had been turned, and Washington had won the precious breathing-time which was all he required.