Ten years ago the dropping of bombs from balloons was still considered an illegitimate form of warfare, involving danger to non-combatants, and was under the ban of the Geneva Convention. At the Hague Peace Conference the Germans refused to abstain from bomb-dropping, and other nations followed suit. According to the German conception of war, civilians in the theater of operations must take their chance of being killed, but must not shoot back under pain of summary execution. The horrors which this theory has added to war have proved only too real, but, so far as bomb-dropping is concerned, the reality has so far fallen short of anticipations. The great Zeppelins, capable of carrying a ton of explosives, have practically been frightened out of the air by the new anti-aircraft guns; and, except for one instance at Antwerp, bomb-dropping has been confined to aeroplanes. Now, in the first place, an aeroplane can carry only a limited weight of bombs--say, two hundred pounds; and in the second place, it is extraordinarily difficult to hit anything with them. If the airman could hover over his target and take deliberate aim, he might be more dangerous; as it is, the German airman finds a cathedral hardly a big enough mark. The British airmen, at Düsseldorf and Lake Constance, adopted a different plan from the Germans; instead of dropping bombs from a great height, they made a steep “vol piqué” down on to the target, turned sharply up again, and dropped the bomb at the moment when the plane was checked by the elevator. This plan is more dangerous, but affords a better chance of hitting. [Illustration: TYPES OF AIR-CRAFT WEAPONS. Fig. 1.--An aeroplane bomb containing 12 lbs. of tetranitranilin, with a screw stem up which the vanes travel in flight and thus “arm” the fuse. Fig. 2.--Steel dart and boxes of darts used by Taube aeroplanes over Paris, showing how they are inverted and released. Fig. 3.--A French “arrow bullet”; very light, but able to kill a man from a height of 1,800 feet. Fig. 4.--A French aerial torpedo used by aeroplanes against Zeppelins, exploding when it has pierced an air-ship’s envelope and is suddenly arrested by the wooden cross.] KINDS OF BOMBS