ON SHIPS OF WAR.*

By N. BARNABY, Esq., C.B., Director of Naval Construction of the Royal Navy, Vice-President. [Read at the Seventeenth Session of the Institution of Naval Architects, 6th April, 1876; the Right Hon. LORD HAMPTON, G.C.B., D.C.L., President, in the Chair.]

I PROPOSE to offer a few general considerations as to ships of war, with a view to clearing the ground for our debates, and endeavouring to define our present position.

It is a frequent remark of journalists that the administrators of the Navy have no plan, and that ships are added to the Navy, at great cost, which, in the course of a few years, will become obsolete. If it could be established that, when the programme of shipbuilding operations for the year is prepared, due heed is not given to the forces of other powers-that would indicate a want of plan culpable enough; but I take it that this is not what is meant. There is a vague idea that the administration should have such foresight as to avoid taking a single step out of the straight road into the position we shall occupy ten or twenty years hence. But this expectation on the part of the public does not take due account of the great change in conditions introduced by new inventions. Take, for example, the invention of the screw-propeller; and of incendiary and explosive shells.

The introduction of the screw-propeller into the Navy in 1844 made a magnificent Navy obsolete; the realisation of the terrible effects of shell fire in 1854 again rendered our grand screw line-of-battle ships and frigates things of the past. I grant that we are bound to take care not to go on so obstinately and so fast in any road as to neglect the signs and warnings that are given us. It is my duty, for example, to detect at once the appearance of a new peril for the ships, or a new source of power for them. I should not be fit for my post if I allowed the history of the past, or the contentions and cares of the present, to draw my eyes away from the threatenings and the promises of the future. Our national position demands that we should immediately appropriate new forces, and our public spirit and wealth always make it possible to do so. I take high ground for the naval constructor, because it is only upon such ground that he can command the acceptance

* Received 30th March, 1876.

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of such statements as I desire to make. I am going to ask you to believe, without giving you the proofs, although I am prepared to give them whenever and wherever you will, that the circumstances and conditions of naval warfare stand at present as follows:— (1) Looking at the relative distances within which the gun, the torpedo, and the ram are operative, and the risks of failure in striking with them, the gun occupies the first place, and the ram the last, as instruments of naval warfare. (2) From this it follows that ships built only for ramming forego the use of two more important weapons. That a ship built wholly for torpedo service is better than a ram, but is still inferior to one built for service with guns only. The advantages of combinations of these weapons follow the same rule. (3) That while the gun is, on the whole, the superior weapon, it can be resisted more easily than either of the others. If it were as difficult to resist the blow of the gun as it is the blow of the torpedo or the ram, naval warfare would cease to be practicable. (4) The growth of resistance to the gun encourages further increase in the power of the gun, and there appears at first sight to be no limit to this increase. The limit will probably be found in the cost of putting the gun afloat with proper protection for it, and proper speed. The cost will be reckoned in view of the exposure of each such gun to loss by the power of the ram and the torpedo when they can be brought within the proper range of their operations. Some people appear to suppose that the constructors of the Navy are only just becoming alive to the dangerous nature of the torpedo, and its probable effect upon the ships. I may, therefore, perhaps be allowed to refer to an opinion expressed in this matter in January, 1867, at the Institution of Civil Engineers, by an Admiralty Constructor, vide Vol. 26 of Transactions of that Institution. He said,-"It must be "borne in mind that, however thick the armour, the bottom of the ship was left as weak "and defenceless as ever. Torpedo boats made proof against almost any firing that "could be directed against them, could be carried in seagoing ships, and doubtless would "be so carried and employed. In view of these new and undeveloped, but terrible agencies, it was desirable not to create a large fleet like that recommended, at the cost "of many millions of money, which, although secure from gunpowder above water, might easily be rendered obsolete and useless, because undefended from gunpowder "fired from beneath." The author of these remarks was myself. (5) The torpedo can be made, within the proper range of its operations, irresistible.

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Before proceeding further upon this matter, I think it desirable to refer to what has already been done in ships of war for the purpose of resisting rams and torpedoes. There have been four important cases of ramming between English iron-clads, viz., the Hercules ramming the Northumberland; the Minotaur bow on to the Bellerophon; the Resistance bow on to the Devastation, and the Iron Duke bow on to the Vanguard. In all cases the blow was unexpected, and the ship was unprepared. In three out of the four

cases the provisions made against an accidental blow of the ram was effective. In the first the outer bottom was torn open, and the wing compartment filled, but no further harm was done. In the second, the armour and frames were driven in bodily four or five inches, but the leakage was confined to the wing compartment. In the third, the armour was not much displaced, and there was no leakage. In the last, the ship was struck with a force as great as is ever likely to be attainable in an action, and in the most fatal place. She was unprepared to receive it, but she, nevertheless, floated more than an hour, and only took in water at the rate of from 15 tons per minute at the commencement, to 27 tons per minute just before she sank. From this we may conclude that the gross area of the openings in the inner bottom could not have exceeded a square foot. If these results are compared with the results of collisions in ordinary ships it will be admitted, I think, that much has been done in ships of war in the way of protection against the ram. Moreover, the Vanguard was greatly inferior in the matter of bulkhead divisions to the ships now in course of construction, such as the Dreadnought, the Alexandra, the Temeraire, the Nelson, Northampton, and the Inflexible, as any one may see who will take the trouble to inspect those ships.

In the matter of defence against torpedoes, the experiments against the bottom of the Oberon showed a far higher resisting power than the double bottom system had been credited with; and, as to one of our most recent ships, the Inflexible, I give a sketch showing what would happen under the action of Whitehead torpedoes. Notwithstanding this, I say it is idle to attempt to form the bottom of a ship strong enough to resist a fair blow from a powerful torpedo. The utmost that can be done is to keep the disabled ship afloat after she has received such a blow. It would be possible to protect the bottoms of ships with armour to

withstand the present charges of the Whitehead and Harvey torpedoes, but this must be done either by giving up some of the defence against the ram in speed, or of the defence against the gun in armour, or by building larger and more costly ships. When this was done, it would only be necessary to increase the charges of the torpedoes, and the armour we had applied would become vulnerable. (6) If the blows of the torpedo are to remain irresistible when fairly delivered, it remains to be considered in what manner and to what extent the attack can be met, because it would appear that it only needs high speed and armour defence in the torpedo ship to give her control over the situation and enable her to come down upon her adversary in the open day and deliver her fatal blows; and, under the cover of darkness, she would not even need armour. The attack, moreover of several fast unarmoured rams or torpedo ships

upon a somewhat slower armoured ship, although involving the probable destruction of some of the attacking vessels, would still expose the armoured ship to fatal blows. (7) The possibility of such attacks by armoured rams or torpedo ships, or by numerous unarmoured vessels of this kind, exposes the costly armour-clad ships to a risk which they ought never to encounter alone. The assailants ought to be brought to bay before they could get within striking distance of the iron-clad by consorts armed like the attacking vessels with the ram and the torpedo, which may take, like them, the chances of being sunk. In other words, I contend that the defence against the ram and the torpedo must be sought for not in the construction of the ship alone or mainly, but also and chiefly in the proper grouping of the forces at the points of attack. Each costly iron-clad ought to be a division defended against the torpedo and the ram by smaller numerous but less important parts of the general forces. (8) If the foregoing considerations are correct there is still place in naval warfare for costly iron-clads with thick armour and powerful guns. There is place also for association with them of unarmoured vessels armed with the torpedo and manned by brave men. (9) There is work also for lightly-armoured and partially-armoured ships, because any armour obliges the adversary to increase the power and diminish the number of his guns. A thinly-armoured ship will receive fewer effective hits than an unarmoured ship, and of the hits which are effective only a small proportion will have any chance of bursting within the ship, because thin armour explodes most shells in the act of perforation, whereas with no armour the explosion would take place after perforation. It may be said that with no armour there might be no explosion, but the chances are small of an explosive projectile getting into a ship, across the decks, and out at the other side without meeting with enough resistance to explode it. (10) Under the name of armoured ships I include all ships in which the means of propulsion and of offence are protected against artillery by iron plating, whether that plating be vertical or horizontal. Horizontal armour is displacing or 'supplementing, and is likely to displace or to supplement still more in the future, vertical armour. The change which has already taken place in this respect may be best indicated by comparing the following ships :

Vertical armour must always be retained to protect the openings in the horizontal armour, the buoyancy and stability of the ship, and, to some extent, the guns and gunners. (11) The introduction of armour-plating has tended to the advantage of England, as compared with her rivals, because it has admitted of the use of iron instead of wood in the construction of ships of war, and it is now established that it not only admits of the use of iron, but it absolutely excludes the use of wood, except for secondary purposes. The establishment of this fact has greatly depreciated the value of Continental iron-clads. Our dependence upon foreign markets for supplies of materials has therefore been got rid of, and our rivals are obliged to come to us for their materials, and follow us in the modes of construction. (12) The torpedo has served, and will serve England also, by giving us the means of defending our coasts and harbours effectively, and the invention of the Whitehead and Harvey torpedoes in particular has placed in the control of our grand fleets of unarmoured merchant ships a weapon with which the most powerful ships of war may be disabled. It therefore raises the value of unarmoured ships for fighting purposes; and this makes our possession of numerous unarmoured and inexpensive peace vessels, and of vastly more numerous and swift merchant steamers, a source of great strength in war. (13) The effect of these conditions upon the matter of speed-which is always a vexed question-is to reduce the speed necessary in the iron-clad for line-of-battle, to maintain it at about the present standard for armoured cruisers, and to increase it in special vessels for despatch service.

I know that these positions are not unassailable, but I believe them to be impregnable. Whoever accepts them will find in them a security against any alarm about our position as compared with Foreign Powers, but he will not find any excuse for ceasing to build iron-clad ships. In my view the iron-clad must continue to occupy the first place in naval warfare; and we have only to remember in how many different and distant parts of the globe we should require to be present in force in a time of war with any great maritime Power to see how far short the number of our iron-clads falls of that which our extended and proud dominion requires.