This last blow lost the Niagara frontier to the British. General Vincent at once gave orders that Forts Chippewa and Erie and all public property as far down as Niagara Falls should be destroyed. The magazine at Fort Erie was fired, and a little later, Lieutenant-Colonel Preston, in command of the Americans at Black Rock, took possession of what remained of the stronghold, thus giving Perry an opportunity to get out of the Niagara River five of the vessels which were to play such an important part in the naval history of Lake Erie. Sacketts Harbour was now in much the same condition that York (Toronto) had been, and was even more poorly defended. The British planned to regain a part of their lost prestige by its capture, and on May 27th, Commodore Sir James Lucas Yeo sailed with a large fleet and a strong land force under Sir George Prevost to make the attack. On the 29th, eight hundred of the British regulars landed, but despite the astonishing inadequacy of the American garrison they were beaten back with a loss of fifty-two killed and two hundred and eleven wounded, while the Americans lost but twenty-three killed and one hundred and fourteen wounded. The British squadron returned to Kingston, and for several weeks thereafter co-operated with the army forces and made several unimportant naval captures while Chauncey awaited the completion of the new ship _Pike_. During July, General Dearborn was recalled from his command at Fort George because of the capture by the British of Lieutenant-Colonel Boerstler and seven hundred men, and during this same month Black Rock was captured by the enemy and recaptured by the Americans, but it was not until the 30th that an important blow was struck by either side. On this day the Americans again descended upon York, destroyed eleven transports, burned the barracks, and captured a considerable quantity of supplies and ammunition.