cotton will be ample. A bomb of torpedo-like form, about 6 in, in diameter, and fitted with a sheet-metal cruciform tail, as shown diagrammatically in Fig. 17, would probably be found suitable; it would be furnished with a positive impact or contact fuse at its nose. The usual way of dropping a bomb of this type is broadside on, pointing in the direction of flight; the axis then remains tangent to the trajectory throughout the fall, the tail acting in the manner of the feathering of an arrow.
A bomb of the type described in the preceding paragraph will travel through water under the influence of gravity at a no inconsiderable velocity. Taking its weight to be (immersed) about half a hundredweight, its limiting velocity in water will be about 50 ft. per second,
_-_Fig._17.png)
Fig. 17.
which is ample to ensure the certain action of the contact fuse. Thus it will be impossible for a submarine to escape by deep immersion, presuming it to remain sufficiently visible to permit of attack.
§ 76. Submarine Activity as Affected by Aircraft. In brief, the aeroplane, and to some degree other aircraft, suitably armed, may be expected to prove an effective check on the unbridled activity of the submarine. With a properly-equipped naval aeroplane service, supported by a few fast, light cruisers, such as the type known as the "destroyer leader," the enemy's submarines will be unable to roam at large or to make unexpected attacks on our cruiser patrols. They will need to operate under the protection of a supporting force, and will only leave that
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