Roads may be blocked with troops, or transport waggons, thereby holding up, temporarily, the passage of any motor-cars or motor-cycles. No such hindrances affect the aeroplane. With such reliable passenger-carrying machines as are now available, staff officers will be able to flit from point to point on a battlefield, with a minimum of delay. This will prove an extremely valuable addition to what may be termed the conveniences of war. It is legitimate, at this juncture, having illustrated the uses of an aeroplane in time of war, to picture, briefly, the contrast between two Commanders-in-Chief, one of them possessing an up-to-date fleet of war aeroplanes, and the other without any such aid. Prior to an action, the one who has an aeroplane corps sends out his machines upon a general reconnaissance. As a result he is, in an hour or so, in possession of all the information he requires concerning the enemy. He is able to calculate where his antagonist’s main blow is to be struck; and he is also able to estimate the weak points in his opponent’s fighting line. The Commander who is without aeroplanes sends out his cavalry scouts, in the time-honoured fashion, and relies upon news from outposts. What information he thus obtains is bound to be many hours older than that, concerning his own movements, which is in the possession of the enemy. Furthermore, it leaves many questions of urgency altogether unanswered. But, unsatisfactory though his knowledge of his opponent’s intentions is, the Commander has to grope forward. A certain blind doggedness actuates him; it is a case, more or less, of hit-or-miss. Now, were his opponent in a similarly fumbling state of mind, it would not matter so much. But, thanks to his aeroplanes, Commander No. 1 has his opponent’s dispositions and movements carefully marked upon his maps. Thus the two armies come into conflict. One Commander-in-Chief knows everything; the other knows practically nothing. What is the result likely to be? One strikes swiftly and surely, aware of the precise strength opposed to him. The other fumbles blindly in the dark. EIGHTH SECTION WIRELESS TELEGRAPHY AND PHOTOGRAPHY AS AIDS TO AERIAL RECONNAISSANCE I. First tests and successes with wireless telegraphy—Difficulty of equipping an aeroplane with transmitting plant. In the descriptions of the uses of an aeroplane in war, which have been set forth in previous sections, nothing has been said concerning an adjunct which now promises to have an importance quite overwhelming upon future operations with aircraft. This has reference to the use of wireless telegraphy. It was thought, at first, that any employment of this marvel of science, so far as aeroplanes were concerned, would be hopeless. The fact that the aeroplane is suspended, so to speak, in mid-air, with no earth communication, made the problem of equipping it with wireless particularly difficult.