It will have two methods of propulsion, one for the surface, one for beneath the water, and its mode of operation will be to steam on the surface until it is within sighting range; to then take in enough water ballast to bring it to the “awash” condition, thus greatly reducing the chances of being hit; and, having approached within a certain distance of the enemy, to sink entirely beneath the waves, rising once probably for a second to take final bearings before firing its torpedo.
The nine vessels ordered for our navy are really diving torpedo-boats and are not intended for use under water except for very short intervals of time. The submarine of to-day bears a close resemblance to the torpedo-boat in the early stages of its development and appears to be of more value to a country that is desirous of defending its coasts than to one which must maintain the command of the seas.
There are signs, however, that in the process of its evolution the submarine will go through many of the same stages as did the torpedo vessel, and will develop into an offensive weapon which England will be unable any longer to despise.
That a Holland, a Narval, or a Gustave Zédé is as formidable an adversary as an Albatross or an Express few would claim, but the last word has not yet been said on submarine navigation, and the future may be expected to bring about many changes.
For purposes of coast defence the submarine may be said to have fairly established its value. The knowledge that such craft were “in being” would have a deterrent influence upon an admiral attacking a fort or contemplating a blockade, and in all probability the days of close blockade are over.
As a weapon of offence the utility of the submarine boat is not so clearly established. It is true that some of the French boats have operated at a considerable distance from their base, but its speed, its seaworthiness, and range of action must be improved before the submarine can be regarded as a useful adjunct to a fleet acting on the offensive. The radius of action at the surface of the newest Hollands is only 400 knots at 8 knots per hour, and submerged the speed is 7 knots for a four hours’ run.
THE “FULTON” RUNNING ON THE SURFACE.
Still even now there are uses to which a submarine boat might be put, such, for instance, as the attack of ships shut up in a blockaded harbour, or of vessels in port; the destruction of a mine field so that ships may enter in safety; the cutting and repairing of cables; the forcing an entrance through a boom, &c.
The late Captain Cairnes, in his book “The Coming Waterloo,” enunciated the theory that even if the British fleet destroyed the French fleet it would still be necessary for us to land an army on French soil in order to bring hostilities to a conclusion. In that case submarine boats would probably be employed, for some of the purposes above enumerated.