But eleven thousand Spanish infantry, three hundred cavalry, and eight guns, had now joined Wellington, who would have fallen on frankly the 17th, if Clausel, alike wary and skilful, had not observed the increased numbers and retired in the night to Frandovinez; he was however next day pushed sharply back to the heights of Burgos, and the following night passed through that town leaving behind large stores of grain. Caffarelli, who had come down to place the castle in a state of defence, now joined him and both retreated upon Briviesca. The allies entered Burgos amidst great confusion. The garrison of the castle had set fire to some houses impeding the defence, the conflagration spread, and the Partidas, gathering like wolves round a carcass, entered the town for mischief. Mr. Sydenham, an eye-witness not unused to scenes of war, thus described their proceedings: “What with the flames and plundering of the guerillas, who are as bad as Tartars and Cossacks of the Kischack or Zagatay hordes, I was afraid Burgos would be entirely destroyed, but order was at length restored by the manful exertions of Don Miguel Alava.” SIEGE OF BURGOS. (Sept. 1812.) Caffarelli had placed eighteen hundred infantry, besides artillery-men, in the castle; and Dubreton, the governor, in courage and skill surpassed even the hopes of his sanguine countrymen. The works inclosed a rugged hill, between which and the river the city of Burgos was situated. An old wall with a new parapet and flanks offered the first line of defence; the second line, within the other, was of earth, a kind of field-retrenchment, but well palisaded; the third line, similarly constructed, contained two elevated points, on one of which was an intrenched building called the White Church, on the other the ancient keep of the castle. This last, the highest point, was intrenched and surmounted with a casemated work called the Napoleon battery, which commanded everything around, save on the north. There the hill of San Michael, only three hundred yards distant and scarcely less elevated than the fortress, was defended by a horn-work with a sloping scarp twenty-five, and a counterscarp ten feet high. This work was merely closed by strong palisades, but was under the fire of the Napoleon battery, well flanked by the castle, and covered in front by intrenchments for out picquets. Nine heavy guns, eleven field-pieces and six mortars or howitzers, were mounted in the fortress; and as the reserve artillery and stores of the Army of Portugal were deposited there the armament could be augmented. FIRST ASSAULT. (Sept. 1812.)