Titus Livius (Livy), The History of Rome, Book 5
Benjamin Oliver Foster, Ph.D., Ed.

7. Appius was already holding his own with the tribunes of the plebs, even in public meetings,¹ when a sudden disaster, from a source which could [p. 25]least have been anticipated, befell the army before² Veii, giving Appius the advantage in the argument, while it increased the mutual good-will of the orders and their ardour for a more vigorous prosecution of the siege. [2] For when they had pushed forward the terrace towards the town, and had all but brought the mantlets into contact with the walls, —more intent upon erecting their works by day than on guarding them by night, —the [3] gate was suddenly flung open, and a vast horde, most of them armed with torches, hurled fire on the works, and in an hour's time terrace and mantlets, that had taken so long to make, were consumed in the flames; and many men perished by the sword or the fire, in vain efforts to save them. [4] When the news of this came to Rome, it filled the City with sadness, the senate with anxiety and apprehension, lest they might now indeed be unable to check the disaffection, either in the City or the camp, and the tribunes might crow over the commonwealth as though they had overthrown it; when lo! [5] those who were of equestrian rating, but had not received horses from the state, having first taken counsel together, came to the senate, and being granted a hearing, volunteered to serve on their own horses. [6] These men had no sooner received a vote of thanks from the senate, in the most honourable terms, and the report of it had spread to the Forum and the City, than the plebeians suddenly ran together to the Curia, and: [7] declared that it was now the turn of the foot-soldiers to proffer extraordinary service to the state, whether it would have them march to Veii, or anywhere else; [8] if they should be led to Veii, they promised that they would not quit their ground [p. 27]until they had taken the enemy's city. [9] Then³ indeed the senate could scarce control its already overflowing joy; for they did not, as with the knights, issue an order to the magistrates to thank them, nor did they call them into the Curia to receive an answer, neither did the senate keep within the House; but each for himself cried out from above,⁴ to the multitude standing in the Comitium, and by speech and gesture signified the general joy. [10] Rome was blest, they said, and invincible and eternal, by reason of this noble harmony; they praised the knights, they praised the plebeians, they extolled the very day itself, and confessed that the courtesy and good-will of the senate had been surpassed. [11] Fathers and commoners mingled their tears of joy, till the Fathers were recalled into the senate-house, and [12??] decreed that the military tribunes should hold an assembly and thank the infantry and the knights, and say to them that the senate would remember their loyalty to their country, and that it was voted that all who had volunteered to serve out of their due order should receive pay. [13] The knights, too, were granted a definite money allowance. Then for the first time cavalry-men began to serve on their own horses. The volunteer army, having marched to Veii, not only replaced the works that had been lost, but added new ones. The city dispatched provisions with more than its former zeal, that nothing might be lacking to an army that had deserved so well.