1º. The enemy durst not advance, except with _concentrated masses_, because, on the weakest line of resistance, he was sure to encounter above twenty thousand men. 2º. If, choosing the Alemtejo, he suddenly dispersed Romana’s troops and even forced back Hill’s, the latter passing the Tagus at Abrantes, and uniting with Beresford, could dispute the passage of the Tagus until the arrival of the army from the north; and no regular and sustained attempt could be made on that side without first besieging Badajos or Elvas to form a place of arms. 3º. A principal attack on the central line could not be made without sufficient notice being given by the collection of magazines at Coria, and by the passage of the Elga and Ponçul, Beresford and Hill could then occupy the Sobreira Formosa. But an invasion on this line, save by a light corps in connexion with other attacks, was not to be expected; for, although the enemy should force the Sobreira and reach Abrantes, he could not besiege the latter, in default of heavy artillery. The Zezere, a large and exceedingly rapid river, with rugged banks, would be in his front, the Tagus on his left, the mountains of Sobreira in his rear, and the troops from Guarda and the valley of the Mondego would have time to fall back. 4º. An attack on Guarda could always be resisted long enough to gain time for the orderly retreat of the troops near Almeida, to the valley of the Mondego, and moreover the road from Belmonte towards Thomar by the valley of the Zezere was purposely broken and obstructed. [Illustration: _Vol. 3, Plate 5._ Defence of _Portugal_ 1810. _Published by T. & W. Boone 1830._]