Note 396 — Chapter VIII · (Year of Rome 700.) (Book V. of the “Commentaries.”) MARCH AGAINST THE TREVIRI—SECOND DESCENT IN BRITAIN.

Ten cohorts formed a legion; but Cæsar does not employ this last expression, because, no doubt, he drew from each of his legions two cohorts, which he left for the guard of the camp. In this manner he preserved the tactical number of five legions, which was more advantageous, and caused each legion to participate in the honour of combating.