The hottest fighting took place at the "Label" bastion, around which there was not a foot of ground that had not been steeped in the blood of friend or foe. However, by degrees the Turks gained a few paces; at the end of August they were lodged in the ditches of the city; and on September 4th they sprung a mine under the "Bourg" bastion; one-half of the city was shaken thereby, and a breach was rent in the bastion wide enough for an assault to be delivered, but the enemy was repulsed. Next day the Turks attacked it with renewed courage, but the valor of the besieged baffled the assailants. On September 10th another mine was sprung under the same bastion, and the breach was so wide that a battalion might have entered it abreast. The danger was extreme, for the garrison was exhausted by fighting, sickness, and incessant labor. The Count de Starhemberg despatched courier after courier to the Duke of Lorraine for succor: "There is not a moment to be lost, Monseigneur," he wrote, "not a moment;" and Vienna, exhausted, saw not yet her liberators arrive. At length, on the 14th, when the whole city was in a stupor in the immediate expectation of an attack, a movement was observed in the enemy's camp which announced that succor was at hand. At five o'clock in the afternoon the Christian army was descried surmounting the Hill of Kahlen, and it made its presence known by a salvo of artillery. John Sobieski had arrived at the head of a valiant army. The Electors of Saxony and of Bavaria with many princes, dukes, and margraves of Germany had brought with them fresh troops. Charles of Lorraine might then dare to march against the Moslems, although he had yet only forty-six thousand men.