Ab urbe condita
Titus Livius (Livy)
Livy. History of Rome, Volumes 1-2. Roberts, Canon, Rev, translator. London, New York: J. M. Dent and Sons; E. P. Dutton and Co., 1912.
In fact their generals had openly given out that they dared not expose an army so heavily laden to the chances of battle, and they must at once return to Samnium and leave their plunder there, after which they would return for a fresh raid.
However true all this might be, Volumnius thought he ought to get further information, and accordingly he despatched some cavalry to pick up any stragglers they might find among the raiders.
On questioning them he learnt that the enemy were halted at the river Volturnus, and were going to move forward at the third watch and take the road to Samnium.
Satisfied with this information he marched on and fixed his camp at such a distance from the enemy that while it was not close enough for his arrival to be detected it was sufficiently near to allow of his surprising them while they were leaving their camp.