The French army designed to act against Portugal advanced, under the command of Marshal Massena, Prince of Esling, who, meeting with no force capable of resisting his numerous legions, soon took Ciudad Rodrigo, and invested Almeida. Lord Wellington, having resolved to retire, sent the cavalry forward to Freixedas, and, on the 28th of July, the THIRD DRAGOON GUARDS took post at Minncae, while the infantry retired behind the Mondego, except the fourth division, which remained at Guarda. The explosion of the magazine at Almeida having decided the fate of that place, and accelerated the advance of the enemy, Lord Wellington fixed his cavalry at Celerico, with posts of observation at Guarda and Trancoso. The enemy advancing in force, the THIRD DRAGOON GUARDS, and other corps, retired on the 15th of September, passed the Mondego, and on the 19th encamped on a plain in front of Montagao. In the mean time a remount of twenty-three men and forty-seven horses joined the regiment under Cornet Homewood. The retreat was continued, and on the 23rd of September the regiment arrived at Busaco, and encamped at Villa Nova, in rear of the main body of the army. The French army was marching upon Lisbon, and Marshal Massena vaunted that he would drive the English into the sea, and the imperial eagles should triumph in the capital of Portugal, when suddenly the rocks of _Busaco_ were seen bristling with bayonets and streaming with British colours. On the 27th of September the French attacked the heights: ascending, with wonderful alacrity the mountain sides, they stormed the position; but were repulsed and driven back with immense slaughter. The THIRD DRAGOON GUARDS were in reserve in the rear, the conflict being on the steep and rugged sides of rocks and mountains, where cavalry could not engage. The enemy having failed in the attack, endeavoured to turn the left flank of the position, when Lord Wellington immediately retired. The inhabitants in the vicinity were all required to quit their homes and proceed with their provisions and movable property in front of the army, and the population (all orders, sexes, and ages) retired like a cloud behind the lines of Torres Vedras, where a series of works, connected with ranges of rocks and mountains, formed something like a fortified citadel of vast extent, which covered Lisbon. The first range of defence extended about twenty miles; the second, and principal range, was from six to ten miles in rear of the first, and it extended about twenty-nine miles; and, at a considerable distance in the rear of the second, was formed a third range of defences: one flank was protected by a flotilla of gun-boats on the Tagus, manned by British seamen; and the other flank by the sea.