C. Julius Caesar, Gallic War

Though Caesar could not perceive the retreat of the enemy for the intervention of the fire, yet, suspecting that they had adopted that method to favor their escape, he made his legions advance, and sent a party of horse to pursue them; but, apprehensive of an ambuscade, and that the enemy might remain in the same place and endeavor to draw our men into a disadvantageous situation, he advances himself but slowly. The horse, being afraid to venture into the smoke and dense line of flame, and those who were bold enough to attempt it being scarcely able to see their horse's heads, gave the enemy free liberty to retreat, through fear of an ambuscade. Thus by a flight, full at once of cowardice and address, they advanced without any loss about ten miles, and encamped in a very strong position. From which, laying numerous ambuscades, both of horse and foot, they did considerable damage to the Roman foragers.