C. Julius Caesar, Gallic War

That day, slight skirmishes of cavalry having taken place near the river, both armies kept in their own positions: the Gauls, because they were awaiting larger forces which had not then arrived; Caesar, [to see] if perchance by pretense of fear he could allure the enemy toward his position, so that he might engage in battle, in front of his camp, on this side of the valley; if he could not accomplish this, that, having inquired about the passes, he might cross the valley and the river with the less hazard. At daybreak the cavalry of the enemy approaches to the camp and joins battle with our horse. Caesar orders the horse to give way purposely, and retreat to the camp: at the same time he orders the camp to be fortified with a higher rampart in all directions, the gates to be barricaded, and in executing these things as much confusion to be shown as possible, and to perform them under the pretense of fear.