By the 1st of June, 1777, an extra supply of four hundred horses was obtained; the batteries were all ready, and by the middle of the month the campaign commenced. The object of Sir William Howe was to draw off Washington from a strong position which he held, enabling him to prevent his opponents from rendering assistance to Burgoyne, and also from advancing on Philadelphia. Every feint was attempted without success; and at last the British General resolved on a genuine invasion of some part south of New York, which would compel Washington to move. During the month of June, only one engagement of any importance took place, at Westfield, between the British under Lord Cornwallis and 3000 Americans under Lord Stirling, in which the latter were defeated with a loss of three guns. At this action, the detachments of Artillery who were present belonged to the 4th Battalion. By the way, a peculiar service for the Royal Artillery to perform is mentioned by Stedman as having been carried out on the 6th July in this year. "The American galleys were destroyed near Skenesborough during Burgoyne's expedition by Captain Carter, of the Artillery, who commanded a Brigade of _gunboats_. He gave chase, and pursued them with such speed, that he captured several of their largest galleys, and obliged them to set the remainder on fire with a considerable number of their bateaux." On the 23rd July 1777, Sir William Howe embarked his army—leaving Sir Henry Clinton in command at New York—and sailed for the south. Until the 22nd August he kept his intended destination a secret, and baffled Washington's speculations, but on that day news came that he had entered Chesapeake Bay, so the American General marched to meet him. On the 25th August Howe disembarked his troops, and marched inland. To prevent the English reaching Philadelphia, the Americans who had been within a very few miles of their enemies, fell back, and occupied the heights beyond the Brandywine river. On the 11th, the English attacked the American position, moving in two columns, one under Lord Cornwallis, the other under General Knyphausen. The former column crossed the river at an unexpected point, and mounting the hill under a heavy protecting fire of Artillery drove the Americans into the woods. General Knyphausen had some severe fighting also, and ultimately succeeded in getting across.