Titus Livius (Livy), The History of Rome, Book 8
Benjamin Oliver Foster, Ph.D., Ed.

10. while the struggle continued, and in some parts of the field the Latins were prevailing by reason of their numbers, the consul Manlius learned of his colleague's end, and having paid to so memorable a death —as justice and piety demanded —its well —merited [2] meed of tears as well as praise, he was for a little while in doubt whether the moment were yet come for the triarii to rise; but afterwards deeming it better to keep them fresh for the final push, he commanded the accensi to advance from the rear before the standards. [3] no sooner had they gone up, than the Latins, supposing their enemies had done [p. 41]the same, sent in their own triarii. These having¹ fought fiercely for some time, and worn themselves out and broken or blunted their spears, yet were driving back the foe, and supposed that they had already won the field and penetrated the last line, when the consul cried out to the Roman triarii: [4] “rise up now, and with fresh strength confront the weary enemy, remembering your country and your parents, your wives and your children, remembering the consul who lies dead that you may conquer.” [5] when the triarii had got to their feet, fresh and sound in their glittering armour, a new and unforeseen array, they received the antepilani into [6??] the gaps between their files, and, raising a shout, threw the enemy's front ranks into disorder, and thrusting their spears into their faces, disposed of the fine flower of their manhood and went through the other maniples almost scatheless, as though their opponents had been unarmed, penetrating their masses with such slaughter as scarce to leave a fourth part of their enemies alive. [7] The Samnites, too, drawn up a little way off at the base of the mountain, were a source of terror to the Latins.

[8] for the rest, of all the citizens and allies, the chief glory of that war went to the consuls; of whom the one had drawn all the threats and menaces of the supernal and infernal gods upon himself alone, and the other had shown such valour and ability in the battle that it is readily agreed by both Romans and Latins who have handed down an account of this engagement that whichever side had been led by Titus Manlius would undoubtedly have been victorious.² [9] The Latins fled to Minturnae. their camp was captured after the battle and many men — [p. 43]chiefly Campanians —were caught and slain there.³ [10] The body of Decius could not be found that day, for night overtook the searchers; on the following day it was fond, covered with missiles, in a great heap of enemies, and was given burial by his colleague in a manner befitting his death.

[11] it seems proper to add here that the consul, dictator, or praetor who devotes the legions of the enemy need not devote himself, but may designate any citizen he likes from a regularly enlisted Roman legion if the man who has been devoted dies, it is deemed that all is well; [12] if he does not die, then an image of him is buried seven feet or more under ground and a sin —offering is slain; where the image has been buried tither a Roman magistrate may not go up. [13] but if he shall choose to devote himself, as Decius did, if he does not die, he cannot sacrifice either for himself or for the people without sin, whether with a victim or with any other offering he shall choose. he who devotes himself has the right to dedicate his arms to Vulcan, or to any other god he likes. [14] The spear on which the consul has stood and prayed must not fall into the hands of an enemy; should this happen, expiation must be made to Mars with the sacrifice of a swine, a sheep, and an ox.