C. Julius Caesar, Gallic War

When he had arrived there, the enemy's scouts, as they were stationed along every part of the river, not expecting an attack, because a great storm had suddenly arisen, were surprised by our soldiers: the infantry and cavalry are quickly transported, under the superintendence of the Roman knights, whom he had appointed to that office. Almost at the same time, a little before daylight, intelligence was given to the enemy that there was an unusual tumult in the camp of the Romans, and that a strong force was marching up the river, and that the sound of oars was distinctly heard in the same quarter, and that soldiers were being conveyed across in ships a little below. On hearing these things, because they were of opinion that the legions were passing in three different places, and that the entire army, being terrified by the revolt of the Aedui, were preparing for flight, they divided their forces also into three divisions. For leaving a guard opposite to the camp and sending a small body in the direction of Metiosedum, with orders to advance as far as the ships would proceed, they led the rest of their troops against Labienus.