But such paltry success could avail the French little, for Bradstreet's capture of Fort Frontenac had already decided the fate of Fort Duquêsne. The French commander, his supplies being cut off, was obliged to dismiss the greater number of his men; otherwise Forbes could hardly have penetrated to the Ohio in that year. The elements fought for the French. Heavy rain ruined Bouquet's new road; the horses being underfed and overworked kept breaking down fast; the magazines at Raystown and Loyalhannon were emptied faster than they could be replenished; and Forbes was in despair. All through October the rain continued until at length it gave place to snow, and the roads became a sea of mud over which retreat and advance were alike impossible. At the beginning of November the General, though now sick unto death, was carried to Loyalhannon, where he decided that no attack could be attempted for that season. Intelligence, however, was brought that the French were so weak in numbers as to be defenceless; and on the 18th, twenty-five hundred picked men marched off without tents or baggage, Forbes himself travelling in a litter at their head. At midnight of the 24th the sentries heard the sound of a distant explosion, and on the next day at dusk the troops reached the blackened ruins of what had been Fort Duquêsne. The fortifications had been blown up; barracks and store-houses were in ashes; there was no sign of anything human except the heads of the Highlanders who had been killed in Grant's engagement, stuck up on poles with their kilts hung in derision round them. Their Highland comrades went mad with rage at the sight; but the French and their allies were gone, having evacuated and destroyed the fort and retired to the fort of Venango farther up the Alleghany river. Forbes planted a stockade around a cluster of huts that were still undestroyed, and named it Pittsburg in honour of the minister. Arrangements were then made for leaving a garrison of two hundred Provincials to hold the post, for there could be no doubt that the French would collect a force from Venango and Niagara to endeavour to retake it. The garrison indeed was far too small, but there was not food enough for more; so this handful of poor men was left perforce to make the best of its solitude during the dreary days of the winter.