§ 118. How long one line would remain in the fight before it was relieved we have no definite knowledge. But we may easily conjecture that it could hardly have been more than 15 minutes in general. Then the second line would advance to the attack, the first would assemble behind it, re-form, rest, and be ready in turn again to take up the fight.
§ 119. Cæsar usually fought in three lines rather than in two. We may suppose that he brought the third line into action only in case the blows inflicted by the other lines successively proved insufficient to cause the enemy to break. Thus the third line was a last reserve.
§ 120. We see that we must imagine the cohorts in battle as in almost constant motion. The two lines are hurled successively against the enemy, giving the latter no rest, and wearing them out by the incessant blows of the cohorts.
§ 121. When the enemy were finally routed, the cavalry was hurled on the fleeing mass to complete their destruction. Cæsar never failed in this way to follow up a beaten foe. Hence his victories, like Napoleon's for the same reason, seldom proved indecisive.
§ 122. Every long distance was divided into day's marches (itinera). After each two or three days of marching, as a rule, followed a day of rest. *
Each day's march (iter) was from one camp to another; so that " a distance of five camps " means a five days' march.
B. G. VII, 36.
§ 123. The Romans aimed to fight only near their own camp. When they were compelled to break this rule, and____________________