I have said that military aviators propose to fly at about three thousand five hundred feet while seeking information. Perhaps this will be increased to about five thousand feet if it can be demonstrated that the reconnaissance officer can clearly discern, from that height, the points which are of military value. This officer will be aided by powerful field glasses, a camera and sketching case, and he will have at hand a wireless outfit which he can use in sending back whatever he may ascertain of value. Upon reporting back to the officer who sent him out he will turn over his sketches and photographs. It is thought that in this way very complete and valuable data will be available. From an aeroplane or balloon the ground presents a very different appearance than it does from our usual man's eye view. It takes time and practice to determine just what the different strange-looking objects are, let alone to determine relative sizes and distances. On this account we have concluded that the reconnaissance officer and pilot must both be trained at the same time. Since this is the case and since there is a decided mental and physical strain connected with long-continued flight, we have gone further and concluded that both officers who fly in the aeroplane must be pilots and both must be trained in reconnaissance duty. In this way each can relieve or "spell" the other. There is much more to this than the mere acting as an aerial chauffeur. To be a successful military aviator a man must be an excellent cross-country flier. He must be an expert topographer or sketcher, he must understand photography and he must be a practical wireless operator, as well as have a knowledge of the theory of wireless. Above all, he must be trained in military art, that most elusive of all subjects. By that we mean that he must understand the military significance of what he sees, he must understand the powers, limitations, and functions of the three great arms–infantry, cavalry, and field artillery, whether used in combination or separately; he must know major and minor tactics to determine the worth or uselessness of a position; he must be able quickly and accurately to reduce his observations to a written report in order that the information gained may be of immediate use to his chief. For all of these reasons we have concluded that we must rely on commissioned officers of the regular army or organised militia, trained in time of peace to fulfil their functions in time of war. We can not place dependence on civilian aviators, for they have not had the training along the highly technical and specialised lines that are necessary. We can not rely on enlisted men of the army, for the same reason.