The French General contented himself with strengthening the defences of Ticonderoga and sending out parties of irregulars to harass Abercromby's communications with Fort Edward. Abercromby for his part remained throughout July and the first days of August glued to his camp at the head of Lake George, losing many men from dysentery but attempting nothing. At last he made over to Bradstreet a force of twenty-five hundred men, Provincial troops for the most part, and sent him to attack the French post of Fort Frontenac, which guarded the outlet of Lake Ontario into the St. Lawrence. The project was Bradstreet's own and had been favourably regarded some time before by Loudoun; but it was only under pressure of a council of war that Abercromby's assent to it was wrung from him. Bradstreet accordingly dropped down to Albany, and advanced by the Mohawk and Onandaga to the site of Oswego, where he launched out on to the lake on the 22nd of August, and on the 25th landed safely near Fort Frontenac. The French garrison being little over one hundred strong could make small resistance, and on the 27th surrendered as prisoners of war, leaving nine vessels, which constituted the entire naval force of the French on the lake, in Bradstreet's hands. The fort was dismantled, two of the ships were carried off, the remainder were burned since there was no fort at Oswego to protect them, and Bradstreet returned triumphant to Albany. The service that he had rendered was of vast importance. The command of Lake Ontario was lost to the French, their communications north and south were severed, the alliance of a number of wavering Indian tribes was secured for the British, and Fort Duquêsne, the point against which Pitt had levelled his third blow, was left isolated and alone. Heartened by this success and by the news of Louisburg, Abercromby began to write vaguely of a second attempt upon Ticonderoga[291] as soon as Amherst should have reinforced him; but it was October before the conqueror of Louisburg reached Lake George, and then both commanders agreed that the season was too far spent for further operations. The troops were accordingly sent into winter quarters, and Canada was saved for another year. It now remains to be seen how matters fared with Brigadier Forbes at Fort Duquêsne.