Meanwhile the soldiers, as their numbers overflowed the crowded camp, dispersed through the porticoes, the temples, and the whole capital, did not know their own headquarters, kept no watch, and ceased to brace themselves by toil. Amidst the enchantments of the city and all shameful excesses, they wasted their strength in idleness, and their energies in riot. At last, reckless even in health, a large portion of them quartered themselves in the notoriously pestilent neighborhood of the Vatican. Hence ensued a great mortality in the ranks. The Tiber was close at hand, and their extreme eagerness for the water and their impatience of the heat weakened the constitutions of the Germans and Gauls, always liable to disease.

From Tacitus’ Annals and Histories, New York: Everyman’s Library, 2009 (first published in 1908), pp. 495-496.