The word “command” has a charm in the art of war peculiar to itself, and in fact to this element belongs a great part, perhaps half the influence which ground exercises on the use of troops. Here many of the sacred relics of military erudition have their root, as, for instance, commanding positions, key positions, strategic manœuvres, etc. We shall take as clear a view of the subject as we can without prolixity, and pass in review the true and the false, reality and exaggeration.
Every exertion of physical force if made upwards is more difficult than if it is made in the contrary direction (downwards); consequently it must be so in fighting; and there are three evident reasons why it is so. First, every height may be regarded as an obstacle to approach; secondly, although the range is not perceptibly greater in shooting down from a height, yet, all geometrical relations being taken into consideration, we have a better chance of hitting than in the opposite case; thirdly, an elevation gives a better command of view. How all these advantages unite themselves together in battle we are not concerned with here; we collect the sum total of the advantages which tactics derives from elevation of position and combine them in one whole which we regard as the first strategic advantage.
But the first and last of these advantages that have been enumerated must appear once more as advantages of strategy itself, for we march and reconnoitre in strategy as well as in tactics; if, therefore, an elevated position is an obstacle to the approach of those on lower ground, that is the second; and the better command of view which this elevated position affords is the third advantage which strategy may derive in this way.