ploding powder multiplied by the capacity of the gun. As, however, there are practical limits to the length of a gun, it may be advisable to increase the diameter, in order to get the requisite power. But this must be done without increasing the diameter of the ball, which would encounter greater resistance if made too large; and piston guns are the obvious resource in such a case— the piston being so contrived that it would be left behind by the ball so soon as it had left the mouth of the gun, and had acquired all the power which a piston could communicate. The projectile itself should have a sustaining power as well as a projectile one, to which end it should contain a certain quantity of rocket composition that would burn during the flight of the ball; and as the velocity of the ball would be high, the rocket gas would operate with little slip, and with much greater efficiency, therefore, than in rockets. The spiral feathers would cause the projectile to revolve in its flight, in the same manner in which a patent log is turned by the water; and any need for rifling the gun would thus be obviated, as the air would act the part of the rifle grooves. By these means far greater ranges and far greater accuracy of aim may be obtained than is at present possible, and it needs no great perspicacity to see that the success of maritime warfare will henceforth depend on the speed of the vessels employed, and the range, force, and accuracy of the projectiles. A small and very swift steamer with projectiles of the kind I have described would be able to destroy at her leisure a vessel like the 'Warrior,' while herself keeping out of range of the best existing guns which the assailed vessel could bring to bear against her opponent. With great accuracy of aim, and by choosing a position where the wind would have little disturbing influence, a large vessel could be struck at a distance at present deemed chimerical, and a few of such vessels as I have described, without any armour at all, would speedily disable any vessel which was not provided with the same species of projectile. Even if the large vessels, however, were to be armed with projectiles of equal range and power, the advantage would still be with the small vessels, as they would be more difficult to hit; and by taking up an external position and firing their guns in converg

FEATURES OF AMERICAN MONITORS.

461

ing lines, of which the assailed object would be the focus, a great advantage would be given in the attack.

The vessels called Monitors, recently constructed in America, and which, I believe, owe their most valuable features to the talents of Ericcson, the eminent Swedish engineer—whose services were lost to this country through the incapacity of the Admiralty at the time of the introduction of the screw-propellerare a very judicious embodiment of the leading principles of ironclad vessels so as to secure the greatest possible efficiency. The constructors of those vessels saw that the thickness of the sides must be very much greater than it is in our iron-clads, to prevent heavy shot from going through them; and this thickness is reconciled with the usual buoyancy by making the sides of the vessel very low, so that only a small area has to be protected. Very powerful guns are employed in these vessels; and as it would be difficult to manœuvre such guns by hand, a steam-engine is introduced for this purpose, which gives great facility in the handling. To protect the guns and gunners from hostile shot, they are placed in towers of iron, the metal of which is 15 inches thick, and these towers are turned like a swing-bridge to enable the gun to be pointed; but the mechanism is so contrived, that the hand of a child acting on the engine will suffice to move the tower. Admiral Porter states that a Monitor of this construction would be able to cross the Atlantic, and attack and sink our iron-clads at her leisure, without being herself liable to injury; and I think he is right in his conclusion, though it was a most indelicate thing for him to have indicated such an occupation for this class of vessels. But persons who infer the helplessness of this country to resist such attacks, from the imbecility of the Admiralty, will find themselves mistaken; and there are obviously two ways in which such Monitors could be destroyed. Those vessels, though immensely strong above the water, are weak below, being there without armour, as they are protected from shot by the water. But a vessel like the 'Warrior,' if armed in a line with the keel-or a little above it--with a great steel blade or horn 40 or 50 feet long, would by running against a Monitor, break into the bottom and sink her. Such a

conflict would be like a sword-fish attacking a whale; and the horn or blade would in no way affect the steering of the vessel, as it would only virtually make her so much longer. Another way in which Monitors could be destroyed, is by running over them. As they are not many feet out of the water, to submerge them for a few feet more, by placing a corresponding weight upon their deck, would sink them altogether; and if we suppose a vessel with a very raking stem, and so trimmed by the stern as to bring the forefoot out of the water, to be run against a Monitor, it will be obvious, if the vessel be a large and heavy one, and the speed of propulsion be high, that she would run up on the deck of the Monitor, and sink her at once. The weight and speed of vessel that would work this catastrophe in the case of any given Monitor, is matter of simple calculation; and it is quite an error, therefore, to imagine that any Monitor yet constructed might not be promptly disposed of. Certainly they might be made tight, like diving-bells, so that even if sunk and ridden over, they would come up again. But this would be a difficult thing to do; and even if it were done, the next step would be, that the attacking vessel would not go over, but would stop upon them. No doubt the Monitor might as easily run into the attacking vessel as the attacking vessel into her, provided the Monitor had equal speed. But the construction of Monitors is not favourable for speed; and if speed is to settle the question, there is no need for iron plating. The fact is, such infallible recipes for victory as Monitors are supposed to constitute, almost always break down. I believe that such vessels may be made sea-worthy; they may be made impenetrable to any guns at present in our navy, and the guns they mount may be able to riddle our iron-clads like so many ships of card-board. All that I grant. But guns can be made to go through the towers and sides of Monitors, though twice as thick as they are all the existing Monitors can easily be outstripped in speed; and vessels with steel horns may rip up their bottoms, and ves. sels built with greatly slanted stems may be made to run over and sink them. It is true there are the guns of the Monitor to be encountered by the attacking vessel. But if that vessel has

Fig. 67.-AMERICAN IRON-CLAD RAM 'DICTATOR.'

Length, 320 feet; breadth, 0 feet; depth, 22 feet; draft, 20 feet.

several decks, and if the deck over the main hold be made into a water-tank, with water-tight trunks communicating between the hold and the decks above, a shot between wind and water would not let water in, as the space is filled with water already; and the attacking vessel, therefore, could not be sunk by any fire the Monitor could bring against her, unless it could be made to pierce through the sea so as to enter the lower hold by which the flotation is given. With the low elevation of the Monitor turrets, however, this does not appear to be a probable contingency. Small rocket-vessels, propelled at a high speed by rocket gas issuing at the stern beneath the water, will probably be used in actual warfare for many purposes; and the same resource may be employed temporarily to increase the speed of large steamers. If, for example, the iron-clads of the 'Warrior' type had a tube opening beneath the water at each quarter, out of which rocket flame and gas were made to issue, the speed of the vessel, while the emission lasted, would be increased; and this temporary acceleration might suffice to give her a decisive superiority over an opponent.