The influence of mountains on the conduct of war is very great; the subject, therefore, is very important for theory. As this influence introduces into action a retarding principle, it belongs chiefly to the defensive. We shall therefore discuss it here in a wider sense than that conveyed by the simple conception, defence of mountains. As we have discovered in our consideration of the subject results which run counter to general opinion in many points, we shall therefore be obliged to enter into rather an elaborate analysis of it.
We shall first examine the tactical nature of the subject, in order to gain the point where it connects itself with strategy.
The endless difficulty attending the march of large columns on mountain roads, the extraordinary strength which a small post obtains by a steep scarp covering its front, and by ravines right and left supporting its flanks, are unquestionably the principal causes why such efficacy and strength are universally attributed to the defence of mountains, so that nothing but the peculiarities in armament and tactics at certain periods has prevented large masses of combatants from engaging in it.
When a column, winding like a serpent, toils its way through narrow ravines up to the top of a mountain, and passes over it at a snail’s pace, artillery and train-drivers, with oaths and shouts, flogging their over-driven cattle through the narrow rugged roads, each broken waggon has to be got out of the way with indescribable trouble, whilst all behind are detained, cursing and blaspheming, every one then thinks to himself,