But the earlier successes of the colonists were soon followed by suffering and defeat. Howe, an active general with a fine army at his back, cleared Long Island in August by a victory at Brooklyn; and Washington, whose force was weakened by withdrawals and defeat and disheartened by the loyal tone of the State in which it was encamped, was forced in the autumn of 1776 to evacuate New York and New Jersey, and to fall back first on the Hudson and then on the Delaware. The Congress prepared to fly from Philadelphia, and a general despair showed itself in cries of peace. But a well-managed surprise and a daring march on the rear of Howe's army restored the spirits of Washington's men, and forced the English general in his turn to fall back on New York. England however was now roused to more serious efforts; and the campaign of 1777 opened with a combined attempt for the suppression of the revolt. An army which had assembled in Canada under General Burgoyne marched in June by way of the Lakes to seize the line of the Hudson. Howe meanwhile sailed up the Chesapeake and advanced on Philadelphia, the temporary capital of the United States and the seat of the Congress. The rout of his little army of seven thousand men at Brandywine forced Washington to abandon Philadelphia, and after a bold but unsuccessful attack on his victors to retire into winter quarters on the banks of the Schuylkill, where the unconquerable resolve with which he nerved his handful of beaten and half-starved troops to face Howe's army in their camp at Valley Forge is the noblest of his triumphs. But in the north the war had taken another colour. Burgoyne's movement had been planned in view of a junction with at least a part of Howe's army from New York; a junction which would have enabled him to seize the line of the Hudson and thus cut off New England from her sister provinces. But Howe was held fast by Washington's resistance and unable to send a man to the north; while the spirit of New England, which had grown dull as the war rolled away from its borders, quickened again at the news of invasion and of the outrages committed by the Indians employed among the English troops. Its militia hurried from town and homestead to a camp with which General Gates had barred the road to Albany; and after a fruitless attack on the American lines, Burgoyne saw himself surrounded on the heights of Saratoga. On the 17th of October his whole force was compelled to surrender.