Besides their arms, which the legendaries scarcely considered as an encumbrance, they were laden with their kitchen furniture, the instruments of fortification, and the provision of many days.

Under this weight, which would oppress the delicacy of a modern soldier, they were trained by a regular step to advance, in about six hours, near twenty miles.

On the appearance of an enemy, they threw aside their baggage, and by easy and rapid evolutions converted the column of march into an order of battle.

The slingers and archers skirmished in the front; the auxiliaries formed the first line, and were seconded or sustained by the strength of the legions; the cavalry covered the flanks, and the military engines were placed in the rear.
Such were the arts of war, by which the Roman emperors defended their extensive conquests, and preserved a military spirit, at a time when every other virtue was oppressed by luxury and despotism.

If, in the consideration of their armies, we pass from their discipline to their numbers, we shall not find it easy to define them with any tolerable accuracy.