The true cause of Massena’s failure was the insufficiency of his means to oppose the English general’s combinations. The French army reduced by sickness to forty thousand fighting men, exclusive of Drouet’s troops at Leiria, would have been unable to maintain its extended position against the attack meditated by lord Wellington; and when Massena, through the means of the fidalgos, knew that the English reinforcements were come, he prepared to retreat. Those troops landed the 2d of March, and, the 6th, the French had evacuated the position of Santarem. [Sidenote: Muster-Rolls of the French Army.] [Sidenote: Appendix, No. VII.] At this time Napoleon directed the armies of Spain to be remodelled. The king’s force was diminished; the army of the south increased; general Drouet was ordered to march with eleven thousand men to the fifth corps, which he was appointed to command, in place of Mortier; the remainder of the ninth corps was to compose two divisions, under the command of Clausel and Foy, and to be incorporated with the army of Portugal. Marmont was appointed to relieve Ney in the command of the sixth corps; Loison was removed to the second corps; and Bessieres was ordered to post six thousand men at Ciudad Rodrigo, to watch the frontiers of Portugal and support Claparede. Of the imperial guards; seven thousand were to assemble at Zamora, to hold the Gallicians in check, and the remainder at Valladolid, with strong parties of cavalry in the space between those places, that intelligence of what was passing in Portugal might be daily received. Thus Massena was enabled to adopt any operation that might seem good to him, without reference to his original base; but the order for the execution of these measures did not reach the armies until a later period. RETREAT OF THE FRENCH FROM SANTAREM.