The loss of the convoy which General Lewenhaupt was conducting to the army rendered further delay necessary, and obliged the king to undertake the siege of Pultowa, in order to gain a firm footing in the country, and to secure the supplies which the place contained. The Swedish battering-train was weak, the powder not only bad from having been frequently injured by the wet and dried again, but very scarce besides. Still, courage and energy were making progress, when, June 27th, on his very birthday, Charles, in repulsing a sally, was struck by a musket-ball that entered his left foot, above the root of the toes, and went out at the heel. The king continued in the field for an hour afterward, giving his orders as usual; but when he retired to his quarters, the leg was so much swelled that the boot had to be cut off, and the wound had so unfavorable an appearance as greatly to alarm the attendants. Charles behaved heroically, as usual. He held his leg to the surgeon with his own hands, nor did a single groan escape him during the terrible operation which the cutting away of some of the fractured bones rendered necessary. At one time his life was despaired of, and a general panic seized the army, but though the wound proved decisive of his fate, the unhappy monarch had what may well be termed the misfortune to recover. The foe drew near. The Czar, well aware of the importance of Pultowa, advanced to its relief with an army of 80,000 men, besides 40,000 irregulars, Kalmucks and Tartars. He brought 150 pieces of artillery along with him. Even with this vast superiority, and after the training of a nine years' war, the Russians did not venture to attack the Swedes, but drew closer and closer around them, till they began at last to intrench themselves within a league of the king's camp. Charles's illness gave them but too much leisure.