Early on the morning of the 23rd September, 1854, the allied armies left their camp on the battlefield of Alma, and marched northwards towards Sebastopol. Traces of the haste in which the Russian army had retreated were at hand on every side. Here a sword, there a pistol, a belt, or even a tunic; the broad track, strewn with such relics, showed clearly the path of the retreat. At length the valley of the Katcha was reached, and the camp pitched for the night. The advance was resumed early next morning, and about mid-day, from the ridge of hills separating the valley of the Katcha from that of the Baltic, the armies looked down upon their goal, Sebastopol. During a brief halt, Marshal St. Arnaud, whose bodily weakness was increasing day by day, dismounted and lay upon the ground. Men noticed that he looked sad and worn. He was, in fact, within a few days of his death. Here a council of war was held, and it was determined that the northern side of Sebastopol was too strong to admit of an immediate assault, and finally the decision was arrived at of executing a flank march inland and attacking Sebastopol from the south. By the 26th September this somewhat perilous movement was carried out with success, and the little seaport of Balaclava surrendered to Lord Raglan without bloodshed. On the same night, Marshal St. Arnaud resigned his command to General Camobert, and three days later he died on board ship, whither he had been carried for passage to France. Balaclava was of vast importance to the allies, as its tiny harbour gave them a means of communication with their fleets whilst these were still out of the range of the guns of Sebastopol. Accordingly the place was garrisoned by troops under Sir Colin Campbell, whilst the main army moved northward a few miles to within a convenient distance of Sebastopol, where they spent many days, some twenty in all, disposing their forces, erecting batteries, and making all the necessary preparations for a prolonged and persistent siege. Meanwhile, the Russians busily fortified the place, glad of the unexpected delay, since they had anticipated an immediate assault. Several of the finest ships were sunk at the mouth of the harbour to keep the allied fleets at bay, and works of counter-fortification went busily forward. Admiral Korniloff and Colonel Todleben were the two chief officers in command, Prince Mentschikoff having withdrawn the main portion of his army to the Baltic, where he remained for a considerable period in a state of extraordinary inactivity. By the 6th October, however, he was prevailed upon to increase the garrison of Sebastopol to some 53,000 men. On the 17th October, 1854, the allied armies opened fire upon Sebastopol, and the deafening cannonade was maintained daily till the evening of the 25th October. An account of the siege and final surrender of Sebastopol is given in a later chapter.