Antiquity, sacrifices or ceremonies by which the ancients purified their cities, fields, armies, or people, defiled by any crime or impurity. Some of these lustrations were public, and others private. There were several ways of performing lustration, viz., by fire, by sulphur, by water, and by air; the last being done by flinging and agitating the air round the thing to be purified. Some of these lustrations were necessary, and could not be dispensed with, as lustrations of houses in time of a plague, or upon the death of any person; others, again, were performed from choice, and at pleasure. The most of the Roman lustrations were not intended to atone for crime, but to secure the blessings of the gods. The public lustrations at Rome were celebrated every fifth year, in which they led a victim thrice round the place to be purified, and in the meantime burned a great quantity of perfumes. The country lustrations were celebrated when sowing was finished, and before the peasants began to reap the corn; in those of the armies, called armilustria, some chosen soldiers, crowned with laurel, led the victims—a cow, a sheep, and a bull—thrice round the army ranged in battle-array in the field of Mars, to which deity the victims were subsequently sacrificed, after pouring out many imprecations upon the enemies of the Romans. The lustrations of the flocks were designed to preserve the flock from disease, contagion, &c., and were performed in this manner:—The shepherd sprinkled them with pure water, thrice surrounded his sheepfold with a composition of savin, laurel, and brimstone set on fire, and afterwards sacrificed to the goddess Pales an offering of boiled milk, wine, a cake, and millet. As for private houses, they were lustrated with water, a fumigation of laurel, juniper, olive tree, savin, and the like; and the victim was commonly a pig. Lustrations made for particular persons were commonly called expiations, and the victims piacula. There were also for infants a kind of lustration by which they were purified,—girls on the third, and boys on the ninth day after their birth; a ceremony which was performed with pure water and spittle. They cast into the river, or at least out of the city, the animals or other things which had served for a lustration or sacrifice of atonement; and thought themselves threatened with some great misfortune when by chance they trod upon them. Part of these ceremonies were abolished by the Emperor Constantine and his successors; the rest subsisted till the Gothic kings became masters of Rome, when they expired. (See Hartung, Die Religion der Römer.)