Hitherto the continual movements of the Spanish army, and the unsettled plans of the Spanish general, rendered it difficult for the French to fix a field of battle; but now Areizaga’s march to St. Cruz had laid his line of operations bare. The French masses were close together, the duke of Belluno could press on the Spanish front with the first corps, and the king, calling the fourth corps from Bayona, could throw twenty-five or thirty thousand men on Areizaga’s rear, by the road of Aranjuez and Ocaña. It was calculated that no danger could arise from this double line of operations, because a single march would bring both the king and Victor upon Areizaga; and if the latter should suddenly assail either, each would be strong enough to sustain the shock. Hence, when Soult knew that the Spaniards were certainly encamped at Santa Cruz, he caused the fifth corps, then in march for Madrid, to move during the night of the 17th upon Aranjuez. The fourth corps received a like order. The king, himself, quitting Madrid, arrived there on the evening of the 18th, with the Royal French Guards, two Spanish battalions of the line, and a brigade of Dessolle’s division which had just arrived; in all about ten thousand men. The same day, the duke of Belluno concentrated the first corps at Villarejo de Salvanés, intending to cross the Tagus at Villa Maurique, and attack the Spanish position on the 19th. A pontoon train, previously prepared at Madrid, enabled the French to repair the broken bridges, near Aranjuez, in two hours; and about one o’clock on the 18th, a division of cavalry, two divisions of infantry of the fourth corps, and the advanced guard of the fifth corps, passed the Tagus, part at the bridge of La Reyna, and part at a ford. General Milhaud with the leading squadrons, immediately pursued a small body of Spanish horsemen; and was thus led to the table-land, between Antiguela and Ocaña, where he suddenly came upon a front of fifteen hundred cavalry supported by three thousand more in reserve. Having only twelve hundred dragoons, he prepared to retire; but at that moment general Paris arrived with another brigade, and was immediately followed by the light cavalry of the fifth corps; the whole making a reinforcement of about two thousand men. With these troops Sebastiani came in person, and took the command at the instant when the Spaniards, seeing the inferiority of the French, were advancing to the charge. CAVALRY COMBAT AT OCAÑA.