Titus Livius (Livy), The History of Rome, Book 1
Rev. Canon Roberts, Ed.

37. After¹ this division of the forces was augmented there was a second collision with the Sabines, in which the increased strength of the Roman army was aided by an artifice. Men were secretly sent to set fire to a vast quantity of logs lying on the banks of the Anio, and float them down the river on rafts. The wind fanned the flames, and as the logs drove against the piles and stuck there they set the bridge² on fire. [2] This incident , occurring during the battle, created a panic among the Sabines and led to their rout, and at the same time prevented their flight; many after escaping from the enemy perished in the river. Their shields floated down the Tiber as far as the City, and being recognised, made it clear that there had been a victory almost before it could be announced.

[3] In that battle the cavalry especially distinguished themselves. They were posted on each wing, and when the infantry in the centre were being forced back it is said that they made such a desperate charge from both sides that they not only arrested the Sabine legions as they were pressing on the retreating Romans, but immediately put them to flight. [4] The Sabines in wild disorder, made for the hills, a few gamed them, by far the greater number, as was stated above, were driven by the cavalry into the river. Tarquin determined to follow them up before they could recover from their panic. [5] He sent the prisoners and booty to Rome; the spoils of the enemy had been devoted to Vulcan, they were accordingly collected into an enormous pile and burnt; then he proceeded forthwith to lead his army into the Sabine territory. [6] In spite of their recent defeat and the hopelessness of repairing it, the Sabines met him with a hastily raised body of militia, as there was no time for concerting a plan of operations. They were again defeated, and as they were now brought to the verge of ruin, sought for peace.