On the 10th of July, M. Chaboust arrived, with a small party of French and some savages, and succeeded in getting into the fort. On the 11th the besieged attempted a sally upon the British trenches, but were instantly overpowered, and pursued till they found shelter under the fire of their guns. By the 14th the besiegers' parallels were finished to the banks of the lake, and the fire became so heavy that the defenders could only find safety in the covered way and behind the ramparts. On the 19th the French schooner Iroquoise arrived from Frontenac, and lay to abreast of the fort, but could not venture in under the English guns, which still, night and day, kept up their harassing fire.
General Prideaux being well informed of the enemy's formidable muster for the relief of the fort, made every preparation that zeal and prudence could suggest to meet their designs; but at this critical moment a melancholy accident deprived the army of his useful services, and gave to another the enjoyment of the honors which he had worthily won. On the evening of the 19th, while issuing some orders in the trenches, unperceived by the gunners in a battery close at hand, a cohorn mortar was unhappily fired, the shell of which burst prematurely, and a splinter struck the gallant general with a deadly wound. The command devolved to the hands of Sir William Johnson.
Meanwhile the besieged, though hardly pressed, were still buoyed up with the hope of relief from their advancing countrymen. On the 23d four savages made their way into the fort with a letter to M. Bouchet, informing him that MM. d'Aubry and De Lignières were at hand with 1200 Frenchmen and a still larger force of Indians, and that they were about to attack the British lines. On the result of this attack hung the fate of Niagara and of all the Western country which still owned the sway of France: preparations were made to second it with all the efforts of the garrison. The cause of the French was, however, already all but desperate; the feeble defenses of the fort shook and crumbled under the heavy and increasing fire of their enemies. An overpowering artillery forbade the approach of their vessel from the lake. The beleaguering trenches intruded within 100 yards of their parapets, and gave shelter to swarms of British and Indian marksmen. The little garrison was worn by toil and wasted by death; the barracks and dwellings were ruined by shot and shell; and, worst of all, the apparently favorable chance in the death of the besieging general had only transferred the conduct of the attack to hands even more able and skillful than those of the deceased. It was true that the French detachment, then about to risk all for their relief, were brave and veteran troops; but their numbers were hopelessly inadequate, and little dependence could be placed in the politic and faithless savages who marched with them, more to witness than to contribute to their success or defeat.