Armored Vessels.
ARCHITECTURAL DEVELOPMENT.
It would be useless to attempt to assemble in chronological order the many propositions that have been submitted to or even entertained by different maritime governments looking towards the building of armored vessels. The first serious attempt made and effectually carried out was by France in 1855, when there were built five floating batteries carrying an armor of five inches, which, although almost totally unmanageable from their bad lines and realizing a speed of but four knots, went into action on the 17th of October in that year and silenced the batteries of Kinburn.
These vessels taught nothing with regard to architectural development, but at the instance of France the English Government built nearly at the same time some vessels quite similar, and the attention which this movement caused led to a consideration of the suggestions of Captain Coles, who, in the same year, sent into action the little cupola vessel Lady Nancy.
Had it not been for the dire necessity for an armored vessel to hold the Merrimac in check, Ericsson would not have won for the United States the credit of introducing the monitor type of vessel. Whilst he was designing the lines and arrangements of the Monitor, Coles was engaged in almost precisely the same work for the Danish Government, designing the Rolf Krake.
From the successful work of the French floating batteries that government passed at a stride to the Gloire, laid down in 1858. Scarcely was this vessel’s frame up before the keel of the Warrior was laid in England. In designing these two ships the honors of development are divided between the countries. England introduced iron ship-construction, France combined thickness and disposition of armor as well as dimensions of vessels which required the least change as development progressed. Before the end of 1862 all Europe had been aroused to the new marine development. France and England already possessed iron-clad fleets, whilst Spain, Italy, Austria, Denmark, Russia, Holland, and Sweden were ordering ships wherever they could be obtained. In the United States a powerful fleet of monitors and armored river gun-boats was being rapidly formed, whilst to this country the eyes of the world were turned for the actual warfare tests of the new idea.
In England the development of the broadside sea-going iron-clad extends from 1858 to 1867. Commencing with the Warrior, there is a gradual increase in dimensions until the maximum of unwieldiness is reached in the Minotaur, the false development ceasing at her and falling back in the Bellerophon and Lord Warden, the last of the pure broadside type, to nearly the dimensions laid down by the French at the commencement of their work. In disposition of armor the English departed in the same manner from true development. Commencing with simply an armored battery in the Warrior, altering to a fully armored main-deck in the Valiant, changing again in the Achilles to an armored water-line and battery, and ending with a full water-line and main-deck armor in the Minotaur and Bellerophon—the system adopted by France at the start. During this period Coles’s turret-ship development commenced with two different types of ships—a harbor-defence type, represented by the old line-of-battle ship Royal Sovereign, which was cut down, armored, and provided with revolving turrets mounted on a low flush deck, and the Rolf Krake, Scorpion, and Wyvern, constructed for foreign governments, and intended as low-freeboard sea-going vessels.
In France the lifetime of the pure broadside type was about the same as in England. Commencing with the Gloire, a tentative development of iron construction was made in the Couronne, but was not followed up. Remaining satisfied with the Gloire type as it was perfected in the Flandre, the French built up a homogeneous and effective fleet, making but one false step in the development. This was in the attempt to carry height and weight of battery to a maximum by introducing a two-decked frigate. In the Magenta and Solferino the armor of the upper gun-deck was confined to the battery, leaving the ends exposed as in the Warrior, but with far more injurious consequences; for the upper works in these ships being of wood were open to the ravages of fire caused by shell and hot shot, which would have inevitably put these ships hors de combat. The turret-ship development was also commenced at this period with the ram Taureau, an amplification of Coles’ Lady Nancy; passing from thence to the Cerbere type, which was closely allied to the American monitors. In the private ship-yards of France, Germany had commenced an independent type with the Prinz Adalbert, a false design which was repeated but once, in the Confederate ram Stonewall. In comparing the developments of France and England, there is one novel feature worthy of remark. France, ignoring iron construction, made no attempt to convert her wooden line-of-battle ships into armored vessels. England, throwing wood construction out entirely as unfit for application, converted a number of her wooden vessels into armored ones.
In the United States, attention was turned almost entirely to the development of the monitor type, passing from the single to the double turreted class, and overstepping the limit in the three-turreted converted ship Roanoke. The Confederates having designed an independent armored battery-ship (Merrimac type), the Federals developed it in the New Ironsides, carrying it to the end in the Dunderberg.
Spain, Austria, and Italy adopted the French development of the broadside ship, the latter country making a false step in the Affondatore, which belonged to the Rolf Krake type. The northern nations introduced the American development almost unchanged.
In 1867 England struck the death-blow to the pure broadside ship by the design of the belt and box ship Enterprise, passing rapidly and in a true line to the Pallas, Penelope, Hercules, Sultan, and ending with the Audacious. During this period the faulty development of Coles’s low-freeboard sea-going turret system culminated in the Captain, with whose loss the inventor perished. His work was not lost, however, for in the Monarch appears the true development of his system. During this period also the English, taking the American monitor type in connection with Coles’s turret, advanced the combination in the Rupert, Cerberus, Glatton, and Fury (Devastation).
In France the broadside type was modified by introducing the short main-deck battery, supplemented by the spar-deck barbette turrets in the Belliqueuse, carried forward in the Alma and culminating in the Ocean and Richelieu.
In the United States, iron-clad development had entirely ceased. In Germany the König Wilhelm represented the full development of the English Enterprise, and the Friedrich Carl entered her fleet as the model of the second-rate armored cruiser belonging to the Alma type. Russia failed in an attempt to advance the New Ironsides type in the cruising iron-clad Perwenec. Holland, with the Buffel, introduced a new type of high-freeboard monitor, and Turkey appeared developing a fleet of the Hercules type.
Since 1871 the English have in their sea-going frigates mainly developed individual ships of different types—the Alexandria, Temeraire, Nelson, and Shannon. Their turreted ships have advanced from the Devastation to the Dreadnought and Inflexible, and with these ships the English have for a time rested.
In France development was stopped for a time by the war, but recommenced in 1875, when the Alma type was perfected in the Victorieuse, and the Redoubtable and Duperré commenced a new departure. Their coast-defence vessels were also remodelled, following closely the ideas expressed in the Glatton, improving on her in the Tonnerre type.
In Italy independent action appears in the new cruising types Venezia and Palestro, and her architects rightly claim half the honor of the last development of turreted vessels. Whether to Italy or to England belongs exclusively the Duilio and Inflexible type is a question that probably will never be satisfactorily answered.
Austria develops independently the Custoza and the Tegetthoff.
Russia makes a false development in the Popoffkas, and a true one in the Duke of Edinburgh.
Germany carries the Monarch development to its highest point in the Preussen, and the Redoubtable development in the Kaiser.
Chili, with the help of England, produces a new and true type in the Almirante Cochrane, and Japan and Portugal each appear with a well-designed reduction of the Redoubtable in the Foo Soo and the Vasco da Gama.
In this rush of development of twenty years it is true that all fleets have been immeasurably strengthened, but it has been at a cost far beyond what the result would warrant. It is only within the past five years that the development of iron-clad architecture can be said to have taken any steady course. As yet the full effects of this forced and feverish course can scarcely be realized; but as fleets grow now slowly and steadily, those nations who have waited a little and profited by the true developments of the more hasty ones will be in a far better position to meet the sudden exigencies of war than those who have counted on numbers of vessels and gross tonnage displacement as a true criterion of naval strength. From the number of cautious nations the United States must be excluded, since in this country the blow given to the development of private ship-building by the civil war and to the development of naval architecture by political intrigue and interference has resulted in the nearly complete destruction of the science itself.
Nothing is more common amongst naval people than speculations and arguments with regard to the true methods of developing a fleet, and it is generally taken for granted amongst those who give the subject but a superficial study that, since the designs that have been created are almost countless in their variety, and that amongst those nations that have attempted an independent development there is not one that does not count as many failures as successes, the matter of design is one of pure guess-work, not stopping to think that, as a rule, the designers themselves are men of the highest abilities, and that with a ship, as with everything else, there are certain limiting circumstances that the nature of the vessel itself forbids violating.
In this respect a comparison of the proportions of the different elements of vessels of varying types affords a useful lesson.
RATIOS OF THE PRINCIPAL ELEMENTS
OF IRON-CLAD VESSELS TO
THEIR DISPLACEMENT.
First-rate, Sea-going, Full-rigged Frigates.
Displacement ranging from 10,500 to 5400 Tons.
| Names. | Hull. | Armor. | Hull and Armor. | Ordnance. | Engines and Boilers. | Coal. | Spars, Crew, and Supplies. |
|---|---|---|---|---|---|---|---|
| French. | |||||||
| Gloire | .472 | .144 | .616 | .066 | .114 | .116 | .088 |
| Magenta | .474 | .161 | .635 | .073 | .107 | .107 | .078 |
| Provence | .441 | .163 | .604 | .065 | .134 | .107 | .090 |
| Marengo | .463 | .180 | .643 | .063 | .111 | .078 | .085 |
| Richelieu | .476 | .195 | .671 | .067 | .095 | .085 | .082 |
| Devastation | .389 | .294 | .683 | .061 | .118 | .064 | .074 |
| Austrian. | |||||||
| Kaiser | .481 | .147 | .628 | .055 | .113 | .083 | .121 |
| Tegetthoff | .342 | .289 | .631 | .051 | .145 | .087 | .086 |
| German. | |||||||
| König Wilhelm | .401 | 216 | .617 | .066 | .121 | .111 | .085 |
| English. | |||||||
| Warrior | .518 | .149 | .667 | .059 | .101 | .098 | .075 |
| Achilles | .504 | .183 | .687 | .048 | .107 | .072 | .086 |
| Minotaur | .493 | .194 | .687 | .047 | .101 | .072 | .093 |
| Bellerophon | .483 | .171 | .654 | .054 | .118 | .085 | .089 |
| Sultan | .428 | .209 | .637 | .062 | .133 | .080 | .088 |
| Hercules | .431 | .199 | .630 | .065 | .138 | .090 | .077 |
| Audacious | .437 | .221 | .658 | .055 | .117 | .085 | .085 |
| Alexandra | .405 | .246 | .651 | .072 | .141 | .053 | .083 |
| Temeraire | .404 | .226 | .630 | .058 | .158 | .060 | .096 |
Second-rate, Sea-going, Full-rigged Frigates.
Displacement ranging between 5150 and 2950 Tons.
| Names. | Hull. | Armor. | Hull and Armor. | Ordnance. | Engines and Boilers. | Coal. | Spars, Crew, and Supplies. |
|---|---|---|---|---|---|---|---|
| French. | |||||||
| Alma | .519 | .234 | .753 | .043 | .107 | .062 | .035 |
| Victorieuse | .475 | .172 | .647 | .075 | .096 | .068 | .114 |
| English. | |||||||
| Pallas | .488 | .153 | .641 | .038 | .162 | .074 | .085 |
| Shannon | .655 | .071 | |||||
| German. | |||||||
| Hansa | .416 | .194 | .610 | .069 | .157 | .067 | .097 |
| Russian. | |||||||
| Duke of Edinburgh | .379 | .112 | .491 | .033 | .197 | .215 | .064 |
| Chilian. | |||||||
| Almirante Cochrane | .073 | .073 | |||||
| Austrian. | |||||||
| Drache | .526 | .133 | .659 | 041 | .086 | .089 | .125 |
| Turreted Sea-going Iron-clads. | |||||||
| Displacement ranging between 11,550 and 8400 Tons. | |||||||
| Devastation | .301 | .341 | .642 | .054 | .117 | .146 | .041 |
| Dreadnought | .342 | .301 | .643 | .048 | .131 | .137 | .041 |
| Inflexible | .327 | .362 | .689 | .070 | .117 | .103 | .021 |
| Duilio | .341 | .315 | .656 | .053 | .117 | .108 | .066 |
| Peter the Great | .366 | .051 | .145 | .092 | |||
| Monarch | .433 | .217 | .650 | .041 | .133 | .072 | .104 |
| Turreted Coast-defence Iron-clads. | |||||||
| Displacement ranging between 5550 and 2550 Tons. | |||||||
| Cerberus | .428 | .369 | .797 | .059 | .077 | .036 | .031 |
| Hotspur | .430 | .309 | .739 | .030 | .133 | .069 | .029 |
| Glatton | .320 | .352 | .672 | .068 | .114 | .112 | .034 |
| Cyclops | .411 | .331 | .742 | .068 | .076 | .082 | .032 |
| Javary | .288 | .373 | .661 | .068 | .106 | .051 | .114 |
| Popoff | .291 | .384 | .675 | .078 | .150 | .047 | .050 |
| Onondaga | .624 | .117 | .741 | .059 | .102 | .068 | .130 |
| Tonnerre | .359 | .371 | .730 | .036 | .118 | .052 | .064 |
Although these tables are too limited to permit of a just appreciation of the development of iron-clad architecture, much profit may be derived from them. For example: it is known that the French have been slow in adopting iron hulls, and at the first glance many are inclined to sneer at their backwardness, but an inspection of the table will show that their caution was well founded. In weight of hull they never passed 48 per cent, while the English with their iron construction did not reach that point as a minimum until the Hercules was designed. Whilst, however, the French had reached the lowest possible limits with wood (between 44 and 48 per cent), the English by constant improvement steadily reduced the weight of their iron hulls from 52 per cent in the Warrior to 44 in the Audacious. The gradual perfection of steel manufacture coming to their assistance permitted the English by partially introducing it to reduce the weight to 40 per cent. At this point the French take up the iron hull and with the Devastation reach 39 per cent. The Austrians, appreciating the value of the saving in weight of hull, build an all-steel hull in the Tegetthoff, bringing the weight to its present minimum of 34 per cent. Since iron manufacture has never been in so advanced a state in France as in England, it is safe to state that had the Gloire’s hull been of iron, it would have absorbed at least 52 per cent of the displacement, a very serious matter in the first stages of iron-clad building. The wisdom of choosing a wooden hull is then sufficiently shown in this one point of saving 6 per cent in weight, and as the French had commenced with a complete armored side, they could not build in iron until the weight of that system was reduced to that of wood. This necessity was all the more urgent as the percentage of armor increased more rapidly than that of hull diminished. From the Gloire to the Richelieu and from the Warrior to the Hercules the regularity of increase is remarkable, being about the same in both countries, and yet an examination of the weight of hull and armor together shows the French to have the advantage. A strictly true comparison of percentages of armor, however, would necessitate a closer examination of the system of application than is permissible in a general summary.
The advantages of a light hull, however, are well shown in the respective percentages of the Devastation and Tegetthoff. The 39 per cent of the Devastation is far beyond the English limit, but it also brings the hull and armor together about the same amount in advance, which is a clear disadvantage to other factors. By saving on the hull, however, the Tegetthoff gets the same high per cent of armor, while weight of hull and armor together are at the very lowest limit.
Passing to the second-rates we find the weight of hull averaging higher and that of armor lower, bringing the total weight about the same. The Duke of Edinburgh is of a special type which can hardly be compared with the others. Her hull of 38 per cent is evidently of iron and steel in the best combination, whilst her very low percentage of armor shows at once that it is extremely limited, bringing the total at least 12 per cent below the average, the reason for which is shown at once by referring to weight of engines and coal, which are carried far beyond the average. This vessel is intended to steam 16 knots, with a coal capacity for 6000 miles at 10 knots.
Turreted vessels having a low freeboard should naturally have a smaller percentage of weight of hull, which is found in the heavier types to range between 30 and 34 per cent (excluding the Peter the Great, which is of a comparatively early construction). As an offset to this, armor is applied until the difference is made up, bringing the total weight about the same. The Onondaga deserves especial examination, as showing the attention (?) paid by Americans to this point. Her weight of hull is 15 per cent more than that of the heaviest wooden hull amongst the French frigates, and 33 per cent more than that of the Javary, a vessel of an exactly similar type. Her armor, turrets included, is 3 per cent less than that of the Gloire, instead of being, as it should, 15 per cent more, and 25 per cent less than that of the Javary. Hull and armor together are at least 10 per cent above the average. By a bad construction of hull a clear 30 per cent of weight was completely wasted.
The very low percentage of ordnance seems no doubt strange to many who talk loosely of heavy guns and projectiles without thinking that this element is one of solid dead weight occupying an immense space. From 5 to 7 per cent includes the entire range, from the vessel sacrificing ordnance to speed to the one with a maximum of ordnance and moderate speed, the Duke of Edinburgh being again an exception. The limits of weights of engines and boilers may be placed at from 11 to 13 per cent, and those of the coal supply from 8 to 11 per cent. Great diversity should be expected in the percentages of ordnance, engines, and coal in the second-rates, depending upon their special objects, yet as is seen there is scarcely 4 per cent difference between the extremes. The remaining percentage should be about the same throughout, with a slight variation for the proportion of sail-power, the total allowance for this latter being from 1 to 3 per cent.
By means of these tables the beginner may get an adequate idea of the limiting proportions of the main elements of a vessel. It is seen that the factor absorbing the greatest proportion of the displacement is the one that calls for a reduction, all others requiring extension. Weight of hull is an obstacle. In armor, by an increase of percentage an increase of defensive power is gained; with ordnance, an increase of offensive power; with boilers and engines, an increase of general effectiveness; with coal, an increase in endurance; while the percentage of spars, crew, and stores is a necessary constant. Thus the development of naval construction is seen to be a matter of vital importance. Had the Onondaga been properly constructed there would have been a useful percentage of fully 20 per cent to have been distributed in making her a sea-going vessel. This fact is plainly brought out in the breastwork modifications of the monitor type, in which the breastwork is a clear addition of dead weight on a similarly formed and proportioned body without being of any assistance as additional freeboard. From the results attained in the Tegetthoff the lowest limit of weight of hull attainable with present perfections of steel construction may be placed at 34 per cent for first-rate frigates and about the same for second-rates. For turreted vessels it may fall to 28 or 27 per cent.
Although weight of armor is in a manner a direct measure of defensive power, it is an objectionable feature and one whose difficulty of counteraction has been almost insurmountable owing to the excessive cost of steel, whose superiority in the end was extremely doubtful. Within the past few years, however, a happy combination of iron and steel has been made which will go far towards saving percentage in weight, although apparently it will for some time to come make a saving in this direction of only the percentage between iron and steel framing. With iron framing and compound armor the same results of weight of hull and armor together may be attained that now hold with steel framing and iron armor, with the advantages of an increase in defensive power at about the same cost.
Wherever it is a question of rearmoring vessels, the compound armor is a great gain to the fighting power of the vessel, although in general the expense of the change is more than the result would warrant. The highest advantages of this armor are reaped by the second-rate cruisers, who retain their speed and coal capacity with an increase of defensive power that brings them within the fighting lines of first-rates.
Capacity for fuel is a matter of the greatest importance in time of war. England alone of all the maritime nations can afford to neglect this point. A man-of-war without steaming-power in war-time is helpless, and yet by the precepts of international law she is debarred from getting this material in foreign ports. Russia, having a peculiarly vulnerable home coast, easily closed and hard to reach, has with great wisdom sacrificed all qualities in her fast cruisers to the two of speed and coal capacity. Keeping her sail-power as the constant factor, the two important ratios of ordnance and armor are reduced to the lowest point, their gain being entirely transferred to the coal capacity.
In considering the most advantageous method of placing and distributing armor, problems without end arise whose consideration requires the most careful weighing of all the different circumstances of its use, and yet it is in this particular that are generally found the most positive assertions and criticisms from those who have given but little or no attention to the subject. For the protection of the battery and above-water sections of a vessel the extremes of position of armor are the vertical, giving the greatest possible extent of protection, and the horizontal, giving none.
Arguments without end are found in favor of this or that type, varying between the two limits. The truth is, however, that there is scarcely any choice between these extremes. Experiment has fully proved that inclining armor at any angle less than 50° is of itself no advantage as regards preventing penetration. Beyond this angle the great increase of weight necessary to make up the vertical space required necessitates a curtailment in extent of armor entirely neutralizing all the benefits of the inclination. There is left then no choice between the vertical complete protection and the horizontal or armored-deck system giving none whatever. In the vertical protection the question of distribution presents itself anew, varying between the long rectangle and the circular turret. The minimum turret diameter may be safely taken at 20 feet inside. Here the greatest economy of room is attained, but this economy involves a reduction in the number of guns, a limitation in the position, and, unless the French barbette turret be used, the possibility of disabling at one blow the greater part of the offensive power of the ship by jamming the turret. With the same amount of armor that is used in a turret of 20 feet, the broadside may be well covered for a length of from 15 to 18 feet, giving protection to double the number of guns. This advantage, however, is purchased at the expense of a more unfavorable disposition of weight and a complication of upper-work framing. These points bear directly upon the service for which the vessel is intended, and are so intimately connected with the whole general type of the vessel that it becomes the most complete absurdity to assert that turrets alone or armored broadsides alone shall be used. As weight of armor increases, the extent of its protection becomes one of the most serious of questions. In ten years from the date of its introduction it became impossible to completely protect the hull of the frigate, and in fifteen years we find it necessary to commence to strip the turreted vessel with her minimum of freeboard. If the greatest architects of the world find themselves almost at a loss to retain the effectiveness of the armor carried whilst keeping within proper bounds in weight, it is certainly idle for those who barely appreciate the necessity for covering battery and steering-gear to assert that armor should be carried thus and so.
The application of horizontal armor presents problems equally abstruse; more so in fact to the designer who does not fully appreciate all the obstacles to be surmounted and the real advantages which are to be obtained. A vessel having a heavy steel deck that shall fully protect her under-water sections and yet permit of such a division of above-water spaces as to permit her to be pierced with impunity whilst that space is left available for the many necessities of circulation and storage, is a consummation of architectural skill the most difficult of attainment.
The matter of properly proportioning the vital factors of a man-of-war, be she iron-clad or unarmored, is one of the highest consideration. To speak of designing ships to carry 40-ton guns and have a speed of 16 knots, and at the same time not to consider what are the absolute limitations in their construction, is as senseless as to attempt to rebuild a monitor without first finding out whether she will float or not after she is built. The Onondaga is an example of the first method of construction, the Puritan of the second. These two vessels represent the condition of naval architecture and construction in the United States for a period of ten years during which the naval architects of all the rest of the world have been advancing at giant strides.
Whilst then we may leave out of consideration those types of vessels which have clearly proved failures, there is not a single one that has been in any way successful that is not deserving of the closest attention and study. Whilst amongst English types we find the greatest diversity of application combined with the very highest architectural skill and development, it must not be forgotten that France, Italy, and Austria have architects second to none in the world, men whose national jealousies and ambitions lead them to totally independent lines of thought and action and whose works are worthy of the highest praise.