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 quæstors, who were generally chosen from the younger nobility, and
were thus prepared for the higher magistracies by acquiring a
practical acquaintance with finance.