Albany rather than retreating to Fort Ticonderoga, reaching Saratoga on September 13. He asked Clinton for support while constructing defenses around the town. Morale among his troops rapidly declined, and an unsuccessful attempt to break past Gates at the Battle of Freeman Farms on September 19 resulted in 600 British casualties. When Clinton advised he could not reach them, Burgoyne's subordinates advised retreat; a reconnaissance in force on October 7 was repulsed by Gates at the Battle of Bemis Heights, forcing them back into Saratoga with heavy losses. By October 11, all hope of escape had vanished; persistent rain reduced the camp to a "squalid hell" of mud and starving cattle, supplies were dangerously low and many of the wounded in agony. Burgoyne capitulated on October 17; around 6,222 soldiers, including German forces commanded by General Friedrich Adolf Riedesel, surrendered their arms before being taken to Boston, where they were to be transported to England. After securing additional supplies, Howe made another attempt on Philadelphia by landing his troops in Chesapeake Bay on August 24. He now compounded failure to support Burgoyne by missing repeated opportunities to destroy his opponent, defeating Washington at the Battle of Brandywine on September 11, then allowing him to withdraw in good order. After dispersing an American detachment at Paoli on September 20, Cornwallis occupied Philadelphia on September 26, with the main force of 9,000 under Howe based just to the north at Germantown. Washington attacked them on October 4, but was repulsed. To prevent Howe's forces in Philadelphia being resupplied by sea, the Patriots erected Fort Mifflin and nearby Fort Mercer on the east and west banks of the Delaware respectively, and placed obstacles in the river south of the city. This was supported by a small flotilla of Continental Navy ships on the Delaware, supplemented by the Pennsylvania State Navy, commanded by John Hazelwood. An attempt by the Royal Navy to take the forts in the October 20 to 22 Battle of Red Bank failed; a second attack captured Fort Mifflin on November 16, while Fort Mercer was abandoned two days later when Cornwallis breached the walls. His supply lines secured, Howe tried to tempt Washington into giving battle, but after inconclusive skirmishing at the Battle of White Marsh from December 5 to 8, he withdrew to Philadelphia for the winter. On December 19, the Americans followed suit and entered winter quarters at