10.  A battle was usually commenced by the light troops, who skirmished with missile weapons; the hasta’ti then advanced to the charge, and if defeated, fell back on the prin’cipes; if the enemy proved still superior, the two front lines retired to the ranks of the tria’rii, which being composed of veteran troops, generally turned the scale.  But this order was not always observed; the number of divisions in the legion made it extremely flexible, and the commander-in-chief could always adapt the form of his line to circumstances.

11.  The levies of troops were made in the Cam’pus Mar’tius, by the tribunes appointed to command the legions.  The tribes which were to supply soldiers were determined by lot, and as each came forward, the tribunes, in their turn, selected such as seemed best fitted for war.  Four legions was most commonly the number in an army.  When the selected individuals had been enrolled as soldiers, one was chosen from each legion to take the military oath of obedience to the generals; the other soldiers swore in succession, to observe the oath taken by their foreman.

12.  Such was the sacredness of this obligation, that even in the midst of the political contests by which the city was distracted, the soldiers, though eager to secure the freedom of their country, would not attempt to gain it by mutiny against their commanders.  On this account the senate frequently declared war, and ordered a levy as an expedient to prevent the enactment of a popular law, and were of course opposed by the tribunes of the people.

13.  There was no part of the Roman discipline more admirable than their form of encampment.  No matter how fatigued the soldiers might be by a long march, or how harassed by a tedious battle, the camp was regularly measured out and fortified by a rampart and ditch, before any one sought sleep or refreshment.  Careful watch was kept during the night, and frequent picquets sent out to guard against a surprise, and to see that the sentinels were vigilant.  As the arrangement in every camp was the same, every soldier knew his exact position, and if an alarm occurred, could easily find the rallying point of his division.  To this excellent system Polyb’ius attributes the superiority of the Romans over the Greeks; for the latter scarcely ever fortified their camp, but chose some place naturally strong, and did not keep their ranks distinct.

14.  The military age extended from the sixteenth to the forty-sixth year; and under the old constitution no one could hold a civic office who had not served ten campaigns.  The horsemen were considered free after serving through ten campaigns, but the foot had to remain during twenty.  Those who had served out their required time were free for the rest of their lives, unless the city was attacked, when all under the age of sixty were obliged to arm in its defence.

15.  In the early ages, when wars were begun and ended in a few days, the soldiers received no pay; but when the conquest of distant countries became the object of Roman ambition, it became necessary to provide for the pay and support of the army.  This office was given to the quaestors, who were generally chosen from the younger nobility, and were thus prepared for the higher magistracies by acquiring a practical acquaintance with finance.