To avoid the danger of any great explosion, the powder was made as occasion required; and this was the more easily effected because Zaragoza contained a royal depôt and refinery for salt-petre, and there were powder-mills in the neighbourhood, which furnished workmen familiar with the process of manufacturing that article. The houses and trees beyond the walls were all demolished and cut down, and the materials carried into the town. The public magazines contained six months’ provisions; the convents were well stocked, and the inhabitants had, likewise, laid up their own stores for several months. General Doyle also sent a convoy into the town from the side of Catalonia, and there was abundance of money, because, in addition to the resources of the town, the military chest of Castaños’s army, which had been supplied only the night before the battle of Tudela, was, in the flight, carried to Zaragoza. [Sidenote: Doyle’s Correspondence, M.S. Cavalhero, Siege of Zaragoza.] Companies of women, enrolled to attend the hospitals and to carry provisions and ammunition to the combatants, were commanded by the countess of Burita, a lady of an heroic disposition, who is said to have displayed the greatest intelligence and the noblest character during both sieges. There were thirteen engineer officers, and eight hundred sappers and miners, composed of excavators formerly employed on the canal, and there were from fifteen hundred to two thousand cannoneers. The regular troops that fled from Tudela, being joined by two small divisions, which retreated, at the same time, from Sanguessa and Caparosa, formed a garrison of thirty thousand men, and, together with the inhabitants and peasantry, presented a mass of fifty thousand combatants, who, with passions excited almost to phrensy, awaited an assault amidst those mighty entrenchments, where each man’s home was a fortress and his family a garrison. To besiege, with only thirty-five thousand men, a city so prepared was truly a gigantic undertaking! SECOND SIEGE OF ZARAGOZA. [Sidenote: Rogniat.] The 20th of December, the two marshals, Moncey and Mortier, having established their hospitals and magazines at Alagon on the Xalon, advanced in three columns against Zaragoza. The first, composed of the infantry of the third corps, marched by the right bank of the canal. The second, composed of general Suchet’s division of the fifth corps, marched between the canal and the Ebro. The third, composed of general Gazan’s division of infantry, crossed the Ebro opposite to Tauste, and from thence made an oblique march to the Gallego river.