The fighting aeroplane sketched is an experimental machine--as are all those built at present for aerial war. It carries no very powerful gun, and is not the formidable craft the future will evolve; but it would have, none the less, a definite value in time of war. When used with an army in the field it would drive off an enemy’s scouts, attack armed and hostile craft, and harass and cripple an airship should it chance to meet one. It need not rely solely upon its gun. Bombs may be carried and dropped when opportunity offers; and as an improvement upon the early method, which was simply to throw these from the machine, there are releasing mechanisms now devised which carry a number of projectiles and drop them one by one as a lever is moved (see Fig. 84). The bombs, which are long, pointed, and balanced so that they will fall head first, are clipped round a barrel rather like that of a revolver, which is fixed beneath the aeroplane’s hull just below the occupants’ seat. Mechanism causes the carrying chamber to revolve and bring each bomb against a releasing catch, which--at a movement of the marksman’s lever--throws it outwards and downward. Bomb-sighting instruments are now being tested, so that a pilot may drop a missile with accuracy upon a given spot. In the early experiments, when a pilot merely leaned forward as he flew, bomb in hand, and guessed his aim, the majority went wide of their mark. Several factors enter into this problem of aim. There is the speed of the machine, its height above the ground, and the question whether a wind may affect the fall of the bomb. Dropped haphazard, a bomb is unlikely to reach its mark. In sighting instruments now provided the marksman finds his altitude, estimates his speed by the time his craft takes to pass between two points on the land below, and then makes an allowance for side-drifting owing to the influence of the wind. Bombs of many types are being made. Some weigh about 10 lbs., and are filled with several pounds of an extremely high explosive. Others are what is known as incendiary bombs; when they strike an object they burst into flames, and are intended to cause fires on the roofs of buildings or supply stores. A single aeroplane, dropping bombs in war, would not be likely to have much effect; but the plan will be to equip squadrons of these machines, their crews trained to sweep in unison over the point attacked, and rain down bombs in a ceaseless and destructive stream.