Maxim XXI
When an army carries with it a battering train, or large convoys of sick and wounded, it cannot march by too short a line upon its depôts.
Note
It is above all in mountainous countries, and in those interspersed with woods and marshes, that it is of importance to observe this maxim; for, the convoys and means of transport being frequently embarrassed in defiles, an enemy by manœuvring may easily disperse the escorts, or make even a successful attack upon the whole army, when it is obliged, from the nature of the country, to march in an extended column.