twelve o'clock
The general intended to make a forced march , keeping by the sea-road . A strong advance guard would press forward and occupy the formidable position of Mathia in the rear of the hills . With the main body he intended to seize some heights a few miles behind Torres Vedras , and to cut the road between that place and Montechique , on the direct road to Lisbon , and so interpose between Junot and the capital . At twelve o'clock that night Sir Arthur was roused by a messenger , who reported that Junot , with 20,000 men , was advancing to attack him , and was but an hour 's march distant . He disbelieved the account of the force of the enemy , and had no doubt but that the messenger 's fears had exaggerated the closeness of his approach . He therefore contented himself with sending orders to the pickets to use redoubled vigilance , and at daylight the whole British force was , as usual , under arms . Nothing could have suited the British commander better than that Junot should attack him , for the position of Vimiera was strong .