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. 16. The soldiers were subject to penalties of life and limb at the discretion of the commander-in-chief, without the intervention of a court-martial; but it deserves to be recorded that this power was rarely abused. 17. There were several species of rewards to excite emulation; the most honourable were, the civic crown of gold to him who had saved the life of a citizen; the mural crown to him who had first scaled the wall of a besieged town; a gilt spear to him who had severely wounded an enemy; but he who had slain and spoiled his foe, received, if a horseman, an ornamental trapping; if a foot soldier, a goblet.