No important line of defence is offered by the Guadalquivir. An army, after passing the Morena, would follow the course of its waters to gain the lower parts of Andalusia, and, thus descending, the advantage of position would be with the invaders. But, to reach the Mediterranean coast, not only the ridges of the Nevada or Ronda must be crossed, but most of the minor parallel ridges enclosing the valleys, whose waters run towards the Atlantic. Now all those valleys contain great towns, such as Jaen and Cordoba, Ubeda, Grenada, and Alcala Real, most of which, formerly fortified, and still retaining their ancient walls, were capable of defence; wherefore the enemy could not have approached the Mediterranean, nor Grenada, nor the lower country about Seville, without first taking Jaen, or Cordoba, or both. The difficulty of besieging those places, while a Spanish army was stationed at Alcala Real, or Ecija, while the mountains, on both flanks and in the rear, were filled with insurgents, and while Albuquerque hung upon the rear at Almada, is apparent. Pompey’s sons, acting upon this system, nearly baffled Cæsar, although that mighty man had friends in the province, and, with his accustomed celerity, fell upon his youthful adversaries before their arrangements were matured. But in this, the third year of the war, the Junta were unprovided with any plan of defence beyond the mere occupation of the passes in the Morena. Those, once forced, Seville was open, and, from that great city, the French could penetrate into all parts, and their communication with Madrid became of secondary importance, because Andalusia abounded in the materials of war, and Seville, the capital of the province, and, from its political position, the most important town in Spain, was furnished with arsenals, cannon-founderies, and all establishments necessary to a great military power. INVASION OF ANDALUSIA. The number of fighting-men destined for this enterprise was about sixty-five thousand. Marshal Soult directed the movements; but the king was disposed to take a more prominent part, in the military arrangements than a due regard for his own interest would justify. To cover Madrid, and to watch the British army, the second corps was posted between Talavera and Toledo, with strong detachments pushed into the valley of the Tagus. Two thousand men, drawn from the reserve, garrisoned the capital; as many were in Toledo, and two battalions occupied minor posts, such as Arganda and Guadalaxara. Gazan’s division was recalled from Castile, Milhaud’s from Aragon; and the first, fourth, and fifth corps, the king’s guards, and the reserve, increased by some reinforcements from France, were directed upon Andalusia.