in the former military establishment of Poland, is the name given to a kind of militia. It Cossack Troop was the most numerous and the most useful of the Polish armies, consisting of the gentry at large, who, in case of invasion, were assembled by a regular summons from the king, with consent of the diet. Every palatinate was divided into districts, over each of which proper officers were appointed; and every person possessing free and noble tenures was bound to military service, either singly or at the head of a certain number of his retainers, according to the extent and nature of his possessions. The troops thus assembled were obliged only to serve for a limited time, and were not under the necessity of marching beyond the limits of their country. They submitted to no discipline but such as they liked themselves; and were very apt to mutiny if detained more than a fortnight in the place appointed for their meeting without marching. The mode of levying and maintaining this army was exactly similar to that practised under the feudal system. Although unfit for the purposes of repelling a foreign enemy, it was considered a powerful instrument in the hands of domestic faction; for the expedition with which it was raised under the feudal regulations facilitated the formation of those dangerous confederacies which suddenly started up on the contested election of a sovereign, or whenever the nobles were at variance with each other.

POSSIBLE COMITATUS, in Law, signifies the power of the county, or the aid and assistance of all the knights, gentlemen, yeomen, labourers, servants, apprentices, &c., and all others within the county that are above the age of 15, except women, ecclesiastical persons, and such as are decrepit and infirm.

This posse comitatus is to be raised where a riot is committed, a posse kept upon a forcible entry, or any force of rescue used contrary to the king's writ, or in opposition to the execution of justice; and it is the duty of all sheriffs to assist justices of the peace in the suppression of riots, &c., and to raise the posse comitatus, or to charge any number of men for that purpose.