The Army Cavalry, he tells us, as distinct from the divisional Cavalry, "must be engaged _en masse_, and not in detail." "It must simultaneously engage its whole fighting strength," as an undivided entity (p. 190 _et seq._), and its proper position is forward of one of the flanks. We have no sooner grasped this principle than we find a separate chapter devoted to the action of "those portions of the Cavalry which find themselves behind the fighting-line, not on the exposed flank." This subdivision, we are vaguely told, "may be the result of circumstances," but there is no indication of what those circumstances are. But this is only one infraction of the principle of unity. In spite of the distractingly vague use of terms such as "front" and "flank," "enemy," "hostile forces," "troops within hostile reach," we are able to distinguish the following functions for the Cavalry mass during the battle: It must conduct (1) a "far-reaching exploration" on the enemy's extreme rear and "probable lines of approach and communication," so as to give warning of the approach of fresh reserves; (2) an "immediate tactical reconnaissance," evidently of the whole battle-front--though the vague expression "against such hostile troops as may be within tactical reach" might mean almost anything. But we are told explicitly later that during the whole course of the battle the Cavalry mass "must in all cases prevent the enemy's patrols from making observations as to the disposition of our own _Army_, while, on the other hand, its own reconnaissance should never cease" (p. 199). We receive a sort of mental dislocation, therefore, when the author resumes: "Screened by these various measures, the Cavalry mass now advances fully deployed for the fight." Were "these measures," then, only to screen the Cavalry mass? But how can detachments, perhaps twenty miles away on the other flank, be said to screen the Cavalry mass? (3) The mass is to provide for the occupation of "defiles and other important places to the flank and front of the main body" (_i.e._, of the main _Army_).