But something more than a land gun is necessary to fight this new foe--something more certain; it must, in a word, be sought and attacked in its own element, the air. There are two ways at present in which aircraft can engage each other; one machine may rise above its adversary, and drop bombs upon it, or two craft may seek to cripple each other by a fire from machine-guns. Other and more deadly methods are discussed, and may even be employed. Attacking an airship, for instance, a man might ascend in a fast monoplane and charge directly at his bulky foe; then, just before the impact, he might spring from his machine and descend by means of a parachute, leaving his empty craft to crash into the airship and cut a gash through its hull. Many things may be done, in fact, when aerial war is faced; but as tactics are now discussed, and plans made, machine-guns and bombs are the weapons reckoned feasible. When one imagines two craft manœuvring for position, and about to engage in a duel in the air, speed would seem a vital need; and here, when opposed to the airship, an aeroplane has advantage. But airships are being built larger and faster in flight; and the speed of an aeroplane, when it has to carry the burden of a gun, is lessened perceptibly; added to which is the fact that, owing to its weight-lifting capacity, the airship can raise a heavier type of gun. The airship may be likened to the battleship of the sky, and the fighting aeroplane to a cruiser; and it seems likely that, in actual warfare, several of the latter will be detailed to attack an airship. Already, anticipating war in the air, a fighting aeroplane has been evolved; and a machine of this type is shown in Fig. 83. The body, in which pilot and gunner sit, is armoured lightly with plates which will resist the penetration of a bullet. Such armouring was found necessary after the use of aeroplanes in Tripoli and the Balkans. When flying unavoidably low in these campaigns, and when fired at from the ground, the wooden bodies of machines were pierced by shot, and in several instances their occupants wounded. [Illustration: FIG. 83.--A Fighting Aeroplane (the Vickers’). A. Machine-gun projecting from opening in bow; B. Gunner’s position; C. Pilot’s seat; D.D. Side windows for observation; E. Engine and propeller.] [Illustration: FIG. 84.--Bomb-releasing mechanism. A. Lower part of aeroplane’s hull; B. Revolving barrel to which bombs are clipped; C. Bombs; D. Releasing mechanism operated by marksman in machine.]