Chapter X: The Ironclad (2)

If shell guns were of small value, what was suitable? Were the old spherical solid shot still capable of beating the defence? A serious effort was made in this country to bring them to do it. The Armstrong rifled breech-loading guns recently adopted had been proving defective and indifferent on service; a return was wisely made to muzzle-loading; and it was in question also to revert to spherical shot and shell. Spherical shot of hardest steel were tried by the _Excellent_, in the hope that they would penetrate 4½-inch plates. Experimental guns were also made, in 1864, to discharge 100-pound balls with charges of 25 pounds of powder; guns so heavy (6½ tons) that it was doubted at the time whether they could be efficiently worked on the broadside of a rolling ship. Should not increased power be obtained by persevering with rifled guns? The advantages possessed by the rifled gun in ranging power, accuracy, capacity of shell, were admitted; nevertheless the navy as a whole favoured the smooth-bore, with its simplicity, rapidity of fire, strength, and greater initial velocity, and thought that, at close ranges, the 100-pounder 6½-ton smooth-bore gun was the best and most suitable weapon for the service. But the rifled gun was advancing rapidly. “By May, 1864, the 7-inch muzzle-loading rifled shunt gun of 6½ tons had been tried in the _Excellent_, and had a good deal shaken the position of the smooth-bore. Captain Key reported that it was more than equal to naval requirements.... It was admirably adapted for the naval service.”[166] This fired a projectile 115 pounds in weight. By June of the following year the target of 9-inch plate representing the side of the _Hercules_ had beaten the latest Armstrong achievement, a 12½-ton 300-pounder. And on this pretext, and judging the defensive power of the whole ship by the defensive power of the thickest patch of its armour, a still more powerful gun was demanded for the navy by the inventor and by the press: a 25-ton 600-pounder.

So rapidly the power of ordnance grew. It has been observed that of this feverish evolution of armour and artillery the circumstances were doubly remarkable. Firstly, no foreign pressure existed which called for such overleaping and experimental advances. The Americans still clung to their smooth-bore system; the French, who like us had adopted breech-loading guns, retained the system in their service and suffered for some years from its continuous inefficiency. Secondly, the navy was itself “unwillingly dragged into the cul-de-sac of experimental construction induced by the clamour of public opinion.” The type, the size of the gun which was to be embodied in our latest warships, was decided mainly by forces outside the navy, and changed from year to year. Naval architecture changed with it. The adoption of the succession of increasingly powerful rifled guns set experts at their wit’s ends devising warships suitable for carrying them; entailed continuous alterations both in the armaments of new ships and in the design of the new ships themselves; but also, as it happened, had the effect of giving this country a mastery over naval material which it has never since surrendered.

The type having been decided for each individual vessel, there remained the question of the disposition of the armament.

Two main considerations guided the evolution of the ironclads of this period in respect of the disposition of their guns: one mainly tactical, the other mainly constructive. It appears probable that, from the date of Trafalgar onward, the limitations of merely broadside fire had been realized; that the end-on attack, such as had obtained in the supreme actions fought by Nelson and Rodney, had shown the weakness of the broadside ship in ahead fire and had made obvious the anomaly that, in all ships-of-the-line, the course of the ship, the direction in which the attack was made, was the very direction in which gunfire was least powerful, if not altogether non-existent. With the coming of steam and the consequent growth of the ram and ramming tactics, this anomaly was more and more apparent; and from the _Warrior_ onwards each new type presented an enhanced effort to provide, particularly, ahead fire. The growth of the gun materially assisted this effort. Ahead fire increased, between the years 1860 and 1880, from zero to a large proportion of the total fire. The broadside ship was for a time abandoned.

The constructive consideration was the requirement of a protected armament capable of the maximum effective fire in all directions. In the first half of the century an increased effectiveness had been obtained, with the old-fashioned truck guns, by adaptation of the ports or by use of specially designed carriages, to permit of as large an arc of training as possible. Even so the arc through which guns could be fired was small, and in the case of the 68-pounder of the _Warrior_ was only thirty degrees before and abaft the beam. The demand for greater utility was emphasized when, with the increase in size of the unit gun, the number of pieces carried by each ship was diminished.

How, then, having regard to these two considerations, should a warship’s guns be disposed? Various methods were adopted. In the first instance, it was seen to be possible to augment the ahead fire of a ship, and to give a wide sweep of training to some of her guns, by indenting the sides; by so shaping the ship’s side-plating as to allow guns mounted in the forward part to fire in the direction of the ship’s longitudinal axis. At first, slight use was made of this method: with the fine lines given to iron ships it appeared practicable in only a small degree. Moreover, it was objected to as causing a “funnelling” effect to the path of fragments of enemy shell or shot; it was found that shrapnel shell, fired at indented embrasures at Shoebury, broke up, and the number of balls which entered the portholes was ten times the number which entered similar portholes on a straight side. But, after the _Minotaur_ class, less length and greater beam were given to ships, and recessed ports and indented sides therefore became more feasible.

As guns increased in weight and individual importance the advantages of concentration became apparent. It was now undoubtedly desirable to protect _all_ the guns; yet, if they had been strung out along the whole length of the ship, the weight, both of the guns and their protective armour, would prove to be an excessive burden to the ship. Hence the advantage of the _central battery_. By concentrating the guns into a central area, an armoured box amidships, the weight of armour necessary to protect them could be kept within reasonable limits, protection was afforded not only to the guns but to the vital parts of the ship, while at the same time the extremities were left lightly loaded. The complete water-line belt of armour was retained, but, both in the French and in the English navy, the system of complete protection as embodied in the _Gloire_ and _Warrior_ was given up.

This device of the central battery was at first used solely for broadside guns. But the desire for ahead fire from behind armour soon caused the adaptation of the battery to allow it. Ports were cut in the two transverse bulkheads, the ship’s sides were indented, suitable gun-mountings were provided whereby some of the battery guns could be shifted from one porthole to another; and in this way it was secured that a fair proportion of the armament could be fired either on the beam or parallel with the keel-line of the ship. A power of offence was given in all directions, and no “point of impunity” existed.

Ingenious were the arrangements resorted to, to obtain the maximum effect from the new medium-sized artillery which superseded the original truck-guns of the _Warrior_ and former warships. The armoured boxes, instead of being made with their sides respectively parallel, and at right angles, to the sides of the ship, were sometimes set diagonally, with their sides at forty-five degrees with fore-and-aft. Sometimes they were octagonal, sometimes with curved bulkheads, sometimes two batteries were superposed one on the other; but always the desire was to utilize each gun over as large as possible an arc of fire, and always the tendency was to augment the ahead fire. The central battery formed a powerful citadel covering the whole beam of the ship amidships. The guns of this citadel, by the power of manœuvring given by the adoption of twin-screw propelling machinery, could, it was argued, be brought to bear in any direction desired. Of all directions, “right ahead” was considered to be of the greatest importance. End-on fighting, it was assumed, would always be resorted to in future; and it was the power of keeping the ship end-on to the enemy which was the great military advantage conferred by twin screws.

A further step in the direction of giving to each gun a large arc of fire was taken in the introduction of the sponson. By means of this circular platform, projecting from the vessel’s side, a gun could be carried so as to fire through an arc of 180 degrees. The same system obtained largely in the French ships of this period; by mounting guns in overhung circular turntables, one at each corner of the central battery _en caponière_, a large effective arc was obtained for them.

Only one step more was necessary: that which would allow each gun to command the whole sweep of the horizon, and to be available for duty upon either beam and any bearing: the adoption of the _centre-line turret_. But before tracing the evolution of the turret, let us recapitulate the typical ships built between 1860 and 1873 which composed our central-battery fleet.

The germ of the central-battery idea may be seen, perhaps, in the belted _Minotaur_, in which, in order to allow the chase guns to be fought from behind armour, a transverse armour bulkhead was worked, at a distance of some 25 feet aft of the bow. Had foreign influence not exerted itself it may be supposed with reason that from the _Minotaur_ the central battery would have been evolved. However this may be, the evolution was hastened by French initiative; for in each of the two wooden ships _Magenta_ and _Solferino_, laid down in ’59, was found a complete two-decked central battery whose whole depth was faced with armour for the protection of fifty-two 5-ton cannon, the rest of the ship’s water-line being protected by an armour belt much narrower than that of the _Gloire_. In imitation of this plan our own designs were prepared; and gradually, and only by a series of steps, we achieved what our rivals had obtained in a single stride.

In ’63 Sir Edward Reed, at that time Mr. Reed, one of the graduates of the school which in ’48 had been established at Portsmouth Dockyard, was appointed to the office of Chief Constructor of the Navy. Possessed of broad and original views and gifted to an unusual degree in the arts of exposition and argument, he made himself responsible for designs of warships differing widely from their large and unwieldy precursors. The first of these was the _Bellerophon_, a short and easily manœuvred, fully rigged belt-and-battery ship, carrying ten 12-ton Armstrong guns for broadside fire in the battery, and two 6-ton guns for ahead fire in a small armoured battery in the bows. Not only in the disposition of her armament was the _Bellerophon_ different from all former ships. She was a radical departure from existing practice in many important respects. Constructionally, she was built on a new “bracket-frame” system designed to give great girder strength for small expenditure of weight, already in vogue for mercantile shipping. The use of watertight compartments was extended as a defence against an enemy ram, the system of double bottoms was extended as a consequence of the introduction of the torpedo. A powerful ram was carried, but the bow took a new form; a U- instead of a V-section was adopted in order to give buoyancy and thus minimize the tendency to plunge which was inherent in a fine-bowed ship; the section near the water-line being fined away so as to form a cut-water. Steel was largely used instead of iron, with a consequent saving of weight. A novel trim was given her--six feet by the stern--to give a deep immersion for the powerful screw and to assist the ship in turning quickly on her heel under the action of the balanced rudder; an adjustment which experience showed to have a detrimental effect on the propulsive efficiency.

Next came the _Enterprise_, a still smaller ship. In the _Bellerophon_, as we have seen, there was no bow fire possible from the central battery; in the _Enterprise_ this was obtained by piercing the athwartship bulkheads of the battery with ports, and substituting movable for fixed bulwarks. The same arrangement was developed in the _Pallas_ and _Penelope_, in which ships the arc of fire of the corner guns of the battery was further extended by the device of indented sides. Then came the _Hercules_, generally like the _Bellerophon_ but with indented sides and, as a novelty, alternative ports in the battery armour by means of which the corner guns could be trained, on revolving platforms, to fire either on the beam or nearly in line with the keel; a system which presented an obvious disadvantage in requiring twelve ports for eight guns. In the _Kaiser_ class, designed by Sir Edward Reed shortly afterwards for the German government, this disadvantage was obviated by the expedient of forming ports in facets of the battery set at forty-five degrees with the keel-line, and by muzzle-pivoting guns.

Both in the _Bellerophon_ and the _Hercules_ axial fire had only been obtained by the provision of special batteries, at the bow and stern, of partially protected guns. Now, this accumulation of weight at the extremities was a feature viewed with disfavour by naval opinion; moreover, these bow batteries did not meet the ever-growing demand for a considerable ahead fire. So in the _Sultan_, which carried a central-battery armament similar to that of the _Hercules_, an upper deck armoured battery was embodied, superposed on the after end of the main deck battery and carrying guns which gave both astern and beam fire; while, for bow fire, two 12-ton guns were mounted in the forecastle, but without any protection.

The central-battery system had now to sustain the greatest attack that had yet been made upon it by the advocates of centre-line turrets. The position of the central-battery school was already somewhat shaken; ordnance had grown to a weight and power which justified the main argument of the turret advocates; Lissa had just shown the importance of being able to concentrate on any one bearing a maximum of offensive power. Controversy raged hotly on the relative merits of turret and central battery.

In these circumstances the Admiralty in ’68 determined to consider both types, with a view to embodying the best arrangement in the new class of vessels then projected. The principal shipbuilders of the country were invited to compete, and were presented with specifications for a first-class warship so widely drawn as to leave them the greatest latitude in design. Of the seven designs submitted, three were of the central-battery type, three were turret ships, and one a compound of the two. After comparison with an Admiralty design produced by Sir Edward Reed, it was decided to adopt this in preference to those of the private firms, and to build a whole class of six ships to it. The result was the _Audacious_ class--of which the best-remembered are the _Iron Duke_ and the ill-fated _Vanguard_. In this class a strong all-round fire was obtained by arranging two central batteries of the same size, one on the main and one on the upper deck. The main deck battery had only broadside ports for its six 12-ton guns, each gun training thirty degrees before and abaft the beam; the upper deck battery had four guns of the same calibre mounted at ports cut in armour facets at forty-five degrees with the keel-line, and training through ninety degrees. To allow axial fire from these guns the upper battery was made to project slightly, sponson fashion, over the sides of the ship, and the bulwarks forward and aft of the battery were set slightly back toward the centre line to enable the guns to fire past them.

A final stage in the evolution of the central-battery ship was attained in the _Alexandra_, laid down in ’72. The type had proved tenacious of life, and, for masted vessels, still held its own up to this point against the turret system. The design for the _Alexandra_ gave as complete an all-round fire as was attainable in a central-battery ironclad; for the first time, it was said, we really had a masted ship with satisfactory all-round fire. Generally like the _Audacious_ class, the _Alexandra_ possessed an advantage in that the two forward guns of the upper deck battery were 25 ton instead of 18 ton, and in having, in addition to the six broadside guns of the main deck battery, two additional 18-ton guns mounted so as to be capable of firing nearly ahead and on the beam as well. Designed to fulfil the requirements of “end-on” fighting, she made a heavy sacrifice of broadside fire to obtain a maximum of bow fire; and at a later date, when a different valuation had come to be placed on axial fire, this sacrifice was noted against her. “She could only take her place at a disadvantage in any form of battle which was suited to the armaments of the ironclads that had gone before her.”[167] Nevertheless she was a formidable vessel. Defensively, too, she was pronounced to be conspicuously successful; her armour belt, which attained a thickness of 12 inches at the water-line amidships, was carried down at the bow to cover and strengthen the stem, and to protect the vessel from a raking fire. For the protection of the stern against a raking fire, an armour bulkhead was worked across the after part, extending to a depth of 6 feet below the water-line.

The _Alexandra_ was the last of the purely “central battery” ships.[168] By the time she was launched experience had set the seal of approval on another type, to the evolution of which we must now revert.

§

It is difficult to trace to its source the invention of the armoured gun-turret. The inventive Ericsson is said to have envisaged at an early age the idea of a protected gun carried on a mobile raft, “an idea probably inspired by his river-rafts in Sweden”; and it is known that at a later date he planned in detail a primitive monitor, the design of which at the outbreak of the Crimean War he offered to Napoleon III. Perhaps the idea, which M. Paixhans first developed in public, of applying iron armour to a sea-going ship, induced the idea of a pivot-gun protected by an armour shield. A protected armament was found, as we have seen, in the French batteries built for the assault of Kinburn: the armoured vessel and the armoured gun were first embodied in the same unit; and though these units were the first to be tried in actual war, yet some years previously, in 1842 or thereabouts, a Mr. Stevens of New York had proposed and made an armoured floating battery. But in neither of these instances was the gun in a turret. The turret idea, like so many other inventions, had an independent development in Europe and in America. In each case war supplied the incentive. In America, in ’62, Ericsson himself produced in a national emergency the _Monitor_, the low, shallow-draft armoured vessel carrying two 11-inch Dahlgren guns in a steam-rotated turret which served to counter the Southern _Merrimac_, the rasée with the fixed penthouse armour roof over its guns which the Confederates had built by the light of French experience.

The _Monitor_, both in design and in the circumstances of its production, was a great achievement; its success gave sanction to the revolving turret as a form of structure by means of which a big gun could be carried and trained. Nevertheless it is doubtful whether it influenced to an appreciable degree the evolution of the sea-going turret ship on this side of the Atlantic. Already, when the _Monitor_ fought her action with the _Merrimac_, the turret had been adopted in coast-defence ships ordered for European powers; and, dramatic though it was, the incident of Hampton Roads afforded merely a confirmation of the effectiveness of the turret form of gun mounting. It was to an episode of the Crimean War that the development of the sea-going turret ship was directly due.

In the Sea of Azov, in the spring of 1855, Commander Cowper Coles, of H.M. steamer _Stromboli_, constructed in a single night, of barrels, spars and boards, a raft capable of bearing heavy artillery, which he named the _Lady Nancy_; by means of which he brought within range and destroyed by shell fire the Russian stores at Taganrog.

The naval operations of this war had drawn general attention to the special problems in connection with the navigation of shallow waters by vessels with a heavy armament, and Commander Coles’ exploit immediately excited official interest. Models of armed rafts were submitted by him for Admiralty inspection, and shortly afterwards he was himself ordered home to give advice upon the requirements of this form of construction: in connection with which the necessity for armour protection for the gun or guns was a point early insisted on by him. In that same year he sketched a design for a belted shallow-draught vessel for the attack of stationary forts which he equipped with guns of the heaviest pattern, each working in a fixed hemispherical shield. From the fixed shield to a revolving turret was a small step. In a short time Commander Coles made himself the enthusiastic exponent of armour-protected guns, mounted in cupolas or turrets on or near the centre-line of a ship so as to give a command over nearly the whole sweep of the horizon. By such a system, he argued, a vessel could be endowed with a concentrated offensive power on any bearing unapproachable by broadside armament, however designed; all guns were effective on almost any bearing without diverting the ship, their force required no evolution to elicit, existing as it did when the ship was at anchor, in dry dock or on a constant course. The height of the turrets gave them a plunging fire, an effect particularly useful now that ships’ sides were armoured and their decks alone remained penetrable.

His advocacy of the turret system, aided by the technical assistance of Mr. Brunel, made a deep impression on a large section of the public and gained the interest of the Prince Consort. He did not profess the technical knowledge of a shipbuilder or designer; but in his insistence on the advantages to be derived from the method of mounting guns on the centre-line he wielded arguments of great natural force, and enlisted in his favour the professional sympathies of eminent builders and naval men. In 1860 he produced before the newly founded Institution of Naval Architects a plan of a sea-going ship carrying nine turrets, seven on the centre-line and two off-set so as to allow ahead fire from three turrets. In the following year he wrote to the Admiralty undertaking to prove that a vessel could be built on his principle of armament 100 feet shorter than the _Warrior_ and in all military respects her superior: “I will guarantee to disable and capture her in an hour; she shall draw four foot less water, require only half the crew, and cost the country for building at least £100,000 less. I am ready to stand or fall on these assertions.”

Such a pronouncement could not be lightly passed over. Moreover, coast-defence vessels embodying the turret system--light-draught vessels characterized by small tonnage, small cost and indifferent sea-going qualities, in combination with massive protection and a large offensive armament--were already being built by the private firms of this country for various foreign powers. In ’61, for instance, Denmark had ordered the _Rolf Krake_, a turret gunboat carrying a 4½-inch belt and four 68-pounder guns, a pair in each of two armoured turrets; which three years later proved her value in action against a nominally superior force. Prussia had ordered her first ironclad, a turret ship. Holland, Italy, Brazil, Russia--all were known to be purchasing coast-defence vessels of the turret type. And two sea-going turret ships which had been ordered by the American Confederates, and which were building in this country--the _Wyvern_ and _Scorpion_--had been seized and purchased by our government.

In these circumstances the Admiralty, though there was a preponderance of official opinion against the idea, resolved to countenance the turret system and give it a trial. The _Royal Sovereign_ was cut down from a three-decker of 120 guns, armoured with a 5½-inch belt and a 1-inch deck, and equipped with four turrets carrying a total of five 12½-ton guns--two in the foremost and one in the remaining turrets. At the same time the _Prince Albert_, also a four-turret ship, was laid down by the firm of Samuda to an Admiralty order. These ships were a distinct success so far as the armament was concerned. They were certainly not ocean-going ships. There were many faults and undesirable features to be found in them. But the disposition of the armament was found satisfactory, and the captain of the _Royal Sovereign_ reported most favourably of his ship, describing her as the most formidable man-of-war; “her handiness, speed, weight of broadside, and the small target she offers, increase tenfold her powers of assault and retreat.”

Time, and the progress of artillery, were on the side of Captain Cowper Coles. He saw, and the Admiralty advisers felt, that although it was possible to work existing guns on the broadside, yet increase in the size and weight of guns would sooner or later necessitate the mounting of them on accurately balanced turntables secured by central pivots on the centre-line. Only by such a method could the largest gun be worked and the full weight of metal be poured, as required, on either broadside. In fact the turret, the original object of which was purely defensive, was now regarded from a quite different point of view: as a convenient device by which guns of the highest calibre could be carried and worked. Was complicated machinery objected to? The common winch, the rack and pinion, were in constant use on every railway turntable, nor had the American turrets ever failed in action or caused a loss of confidence in their reliability. Reliance upon a central pivot was disliked? Yet the pivot was already in use for holding the broadside guns of our ironclads--a mere bolt 4 inches in diameter and itself exposed to gunfire.[169]

The Admiralty constructors were insistent on the practical difficulties which lay in the way of designing a satisfactory sea-going turret ship. The advantages which had been claimed for turrets were obvious, said Sir Edward Reed; the larger and heavier the individual gun, the greater the gain of mounting it in a turret. But enthusiastic advocates of this method lost sight of the fact that turrets were incompatible with masts and sails, and with the forecastle and high freeboard necessary for good sea-going qualities. At that time, 1865, it was possible to protect and work eight of the largest guns, mounted on the broadside, with as little expenditure of weight as would be required to mount four of the guns two in a turret on the centre-line; while in the latter case they could only fire in two different directions at the same time, whereas in the former they could fire in eight.

In order to allow both sides in the controversy to come to grips with the practical difficulties, a committee was formed at the Admiralty in May, ’65, and Captain Coles was asked to produce a turret-ship design by the aid of a draughtsman and with the drawings of the _Pallas_ for guidance. His design, a vessel showing two 600-pounders each mounted in a centre-line cupola, was not considered suitable. So the Board resolved to build a ship to Sir Edward Reed’s design--a fully rigged and masted, high-freeboard ship, with an armour belt and protected bow and stern batteries, and with two centre-line turrets amidships mounted over a central battery, each carrying two 25-ton 600-pounder guns. This was the _Monarch_. She was the first truly ocean-going turret ship, and her performances at sea in ’69 in company with central-battery ships like the _Bellerophon_ and _Hercules_ proved her to be a valuable and efficient unit; by this experiment it was demonstrated, said Mr. Brassey, “that it was practicable to design a thoroughly seaworthy turret ship, although for sea-going purposes a central battery presents great advantages over the turret system.”

In the meantime Captain Coles had protested vigorously against the design of the _Monarch_ as representative of his system. The plan was not his; the turrets were mounted so high that there was a large area to protect and the ship, unlike the low-freeboard ships of his own design, presented a large target. But his chief objection was, that the presence of a forecastle and an armoured bow battery annihilated the whole advantage of turret guns by preventing ahead fire from them. After protracted negotiations he obtained Admiralty permission to have a ship built to satisfy his own views and independently of criticism from Admiralty officials. In ’69 the _Captain_, built by Messrs. Laird to his drawings, was launched at Birkenhead. The _Captain_, although generally similar to the _Monarch_ (the growth of artillery limited the number of the turrets to two), differed from her in one important respect: her designed freeboard was only 8 feet as compared with 14; and, by some error in calculation, this dimension proved to be only 6 feet when the vessel was in sea-going trim. This low freeboard, in conjunction with her large sail-area, produced a condition of instability at large angles of heel which led to disaster and sealed the doom of the fully rigged turret ship.

Even in the _Captain_ ahead fire was not found possible. In the original plans she had the low freeboard favoured by her designer; but in the later plans poops and forecastles were added to give the necessary sea-going qualities, and ahead fire was thereby sacrificed. Complete mastage was given her: iron masts in the form of tripods to avoid the use of shrouds and to give as clear an arc of fire as possible. The rigging was all stopped short at, and worked from, a narrow flying deck which was built above the turrets. This flying deck provided a working space for the crew, who in a moderately rough sea would not be able to make use of the low upper deck.

From a photograph by Symonds, Portsmouth]

On the night of September 6th, 1870, the _Captain_ capsized in a heavy sea off C. Finisterre. In St. Paul’s Cathedral the memorial brass, erected in commemoration of this disaster, records that the _Captain_ was built in deference to public opinion expressed in parliament and through other channels, and in opposition to the views and opinions of the Controller and his department; and that the evidence all tended to show that they generally disapproved of her construction.

§

The difficulty of combining the turret system with a full rig of masts and sails had for a long time been recognized. Some eighteen months before the loss of the _Captain_, the Admiralty, in the presence of the increasing efficiency of steam machinery, had decided to construct a mastless sea-going turret ship.

American experience greatly influenced this decision. In America, where the principle of machinery for propulsion and for working the guns had been accepted with a greater readiness than in Europe, the line of development had been more direct. From the original _Monitor_ a whole series of derivatives had been produced, and from coast-defence vessels of a single turret advance had been made to ocean-going mastless turret ships of low freeboard, carrying the largest smooth-bore guns. These ocean monitors, lacking though they did some features which were considered indispensable in British warships, yet exerted an undoubted influence upon our own construction. Weakly designed in many respects, with small fuel capacity, and unsteady as gun platforms, they were regarded by some writers as the true progenitors of the class of warship which now superseded the masted vessels of the ’sixties.

The problem of the naval architect henceforth was greatly simplified. Masts and sails, which had in the past proved such an embarrassment, were now frankly abandoned, with the result that a thousand difficulties which had beset the designer of the turret ship were swept away. No longer had the stability curve to conform to the conflicting requirements of the sailing vessel and the gun platform. The large weight gained by dispensing with masts and sails could be embodied as an addition to the armament or to the fuel carried. The single screw, which in the case of a ship intended to use sails had been almost a necessity, could be replaced by twin screws of greater power; and the change would remove the liability of complete disablement, and give a number of constructive advantages which it is unnecessary to enumerate. Indeed, it may be said conversely, that the adoption of twin screws so improved the reliability of the propelling machinery as to make practicable the abandonment of masts and sails.

In April, 1869, the _Devastation_ was commenced. Designed by Sir Edward Reed, she “forestalled, rather than profited by, the dreadful lesson of the _Captain_ and by her success gave proof of the judgment and initiative of the Board and their adviser.” Sir Edward Reed had recognized, more fully than his critics, the conflicting elements inherent in the rigged turret ship. And it is significant that, just at a time when the assured success of the _Monarch_ must have been a gratification to her designer, he should record: “My clear and strong conviction at the moment of writing these lines [March 31st, 1869] is that no satisfactorily designed turret ship with rigging has yet been built, or even laid down.”

The _Devastation_ design was a development of those of some previous mastless turret ships, the _Cerberus_, the _Hotspur_, and the _Glatton_ class, which had embodied Sir Edward Reed’s ideas as to the requirements of coast-service vessels. At first given four 25-ton guns, the _Devastation_ was ultimately armed with four M.L. guns each weighing 35 tons and carried in turrets on the centre-line, one at each end of a central breastwork, 150 feet in length, built round the funnels.

This central breastwork, raised above the upper deck and armoured along its sides with 10-inch steel, supported the two turrets and enabled the guns to be carried at a desirable height above the water-line. The upper deck itself was low. The sides, up to its level, were protected by a complete belt of armour 8 inches in thickness.

The abolition of masts and rigging had a striking effect on the design. Compared with the _Monarch_, of nearly the same tonnage, she carried heavier guns, double the weight of armour, double the amount of fuel, and required little more than half the crew to work her.

The loss of the _Captain_, confirming the doubts which experts had expressed as to the seaworthiness of rigged turret ships, caused an alarm for the safety of all turret ships, built and building. In the public mind, in consequence of the reported shortcomings of the American monitors and the known deficiencies of our coast-defence vessels, the belief was growing that the turret system was inherently unsafe. It was believed, also, that mastless ships, having no spread of sail to steady their motion, would be liable to excessive and dangerous rolling. To allay the uneasiness as to the safety of the _Devastation_ and her type a Committee on Designs was formed. The Committee, composed of some of the most eminent of naval architects and officers, made a report in the spring of ’71 which, though it met with considerable opposition from one school, nevertheless “formed the groundwork upon which the English Admiralty determined to construct their policy for the future.” The Committee pronounced altogether against fully rigged ships for the line of battle; it was impossible, in their opinion, to combine in the same vessel great offensive and defensive power and a full spread of canvas. They considered the _Devastation_ class as the most suitable type of armoured ship for future service, and found them to have sufficient stability for safety and to be in almost all respects a satisfactory design of warship. As regards the _Devastation_ herself they recommended some minor alterations, the effect of which was to improve the stability of the ship and to give greater accommodation for the crew. The main alteration consisted in the carrying up of the ship’s sides amidships to the level of the central breastwork, and in continuing the breastwork deck outward to the sides, to form unarmoured side superstructures.

Besides the _Devastation_, two others of the type were laid down shortly afterwards, the _Thunderer_ and the _Dreadnought_. The three ships differed from each other slightly in dimensions, but embodied the same characteristic features. Of chief interest is the transition of the unarmoured side superstructures, in the _Devastation_, to an armoured central battery of the same width as the ship, in the _Dreadnought_. The influence of Sir Edward Reed, who had now given place to Mr. Nathaniel Barnaby as Chief Constructor at the Admiralty, was apparent in this evolution. In ’73 he stated publicly his objections to the carrying up of the _Devastation’s_ sides, and pictured a shell entering the unarmoured superstructure and blowing up all the light iron structure in front of the guns. The result was seen in the _Dreadnought_, in which the breastwork was made a continuation of the ship’s side and armoured. More freeboard was also given to the forecastle and the after deck than was found in the _Devastation_ and _Thunderer_, with the desire to make the vessel drier and more comfortable; and, owing to the height at which the turrets were carried, this was found possible without restricting the arcs of fire of the guns. The movement from the monitor type toward the modern battleship in respect of freeboard is clearly traced in these three ships of the _Devastation_ class. Low freeboard, in spite of its effect in rendering inconspicuous the ship in which it was embodied, was gradually being abandoned. High freeboard was foreshadowed for future ships. The loss of the _Captain_ had led to a serious study, by naval architects and mathematicians, of the stability of warships at large angles of rolling, and the advantages of high freeboard were by this time widely appreciated. High freeboard not only made a ship more habitable; by the form of stability curve it gave it allowed a vessel’s beam to be reduced with safety, and thereby contributed to a steadier and more easily propelled ship than would have been obtained without it.

In other respects these three ships show the lines along which progress was being made. In the turrets of the _Devastation_ the twin 35-ton guns had been loaded and worked by hand; but in the forward turret of the _Thunderer_ the new hydraulic system of Messrs. Armstrong was applied with success to two 38-ton 12-inch guns; and this system was adopted for both turrets of the _Dreadnought_. The guns were loaded externally, the turrets being revolved by steam, after firing, till the guns were on the requisite bearing; they were then depressed by hydraulic power, and the 700-pound projectiles were rammed into their muzzles by a telescopic hydraulic rammer. In 1879 an accident occurred in the _Thunderer_ which helped, it is said, to hasten the return to breech-loading guns. Simultaneous firing was being carried out; one of the guns missed fire without anyone either inside or outside the turret being aware of it. The guns were loaded again, and, on being discharged, one of them burst. Such double-loading, it was clearly seen, would not have obtained with breech-loading guns.

The _Devastation_ had twin screws driven by independent engines, but these were non-compound engines of the trunk type working with a maximum steam pressure of 30 lbs. per square inch. In the _Dreadnought_ an advance had been made to compound the three-cylinder vertical engines, working with 60 lbs. per square inch in engine-rooms divided by a longitudinal watertight bulkhead.

§

The evolution of the battleship was being forced along at a hot pace by the evolution of artillery. No sooner had the mastless turret ship received the sanction of the Committee on Designs as the standard type for warfare of the immediate future, than a sudden increase in the power of guns necessitated the consideration of new principles and brought into being a new type.

So far, defence had managed to compete fairly successfully with offence; the naval architect, by devoting as much as 25 per cent of the total of a ship’s weight to protective armour, had been able to keep level with the artillerist. But it was clear that he could not follow much further, by the existing methods. Armour could not be thickened indefinitely. Penetrable armour was no better than none; worse, in fact, since it was a superfluity, and in a ship a superfluity was doubly wasteful, implying a loss of strength in some other direction. Armour might have to go altogether? It seemed that, after all, the predictions of Sir Howard Douglas might well come true; that, just as gunpowder had forced the foot soldier, after burdening him with an ever-increasing weight, to dispense altogether with body-armour, so rifled artillery would render ship armour increasingly ineffectual and, eventually, an altogether useless encumbrance.

The advance in artillery took place in connection with Italian construction. In 1872 Italy laid down the _Duilio_, and a year later the _Dandolo_, two mastless turret ships of a novel class, engined by Penn and Maudsley, and equipped with two diagonally placed turrets each designed to carry two 60-ton Armstrong guns; guns which were afterwards changed to 100-ton guns of 17¾ inches bore. In the same ships the Italians introduced a solution of the armour difficulty. They abandoned vertical armour altogether, except for a very thick belt over the central portion of each vessel which was to protect the vital machinery and the gun turrets.

The reply to these was the _Inflexible_, laid down in ’74.

We have already seen how, in the last of the _Devastation_ class, the central armoured breastwork was widened to the full beam of the ship. It had been proposed by Mr. Barnaby to take advantage of this arrangement to off-set the two turrets of the _Dreadnought_ at a distance each side of the centre line of the ship, so as to allow a powerful ahead fire. Although not then approved, this suggestion was embodied in the _Inflexible_ as her most distinctive feature. In this, however, she was forestalled by the Italians. Her two turrets, each weighing 750 tons, were carried diagonally on a central armoured citadel plated with compound armour of a maximum thickness of 24 inches. Forward and aft of this citadel the unarmoured ends were built flush with it, and along the centre line was built, the whole length of the ship, a narrow superstructure. This superstructure did not contribute anything to her stability; nor was such contribution needed in view of the comparatively high freeboard. But it rendered unnecessary a flying deck such as had been fitted in the _Devastation_ class, and provided accommodation for the crew, without restricting to any appreciable degree the arcs of fire of the big guns.

The _Inflexible_ was of over 11,000 tons displacement, the heaviest and most powerful warship that had ever been built. She was 320 feet in length and 75 feet broad at the water-line; this unprecedented beam being required, in spite of the high freeboard, on account of the height at which the turrets were carried. Nevertheless, so improved was her propulsive efficiency as compared with that of former ships, so great the gain resulting from Mr. Froude’s historic researches on ship form and the action of propellers, that a speed of 15 knots was obtained at a relatively small expense in horse-power.

The idea of sails was not yet altogether dead. In deference to a strong naval opinion she was originally designed to carry two pole masts, with sails for steadying her motion in a seaway and as a standby in the event of her propelling machinery being disabled. But this scheme was modified owing to the possibility of falling masts and rigging interfering with the working of guns and screw in action. It was decided that she should be brig-rigged for peace service; and that, on an anticipation of war, she should be docked to allow the cruising masts to be removed and replaced by two short iron masts without yards for signalling and for carrying crows’ nests.

But it was in the bold abandonment of armour for the ends of the ship and its concentration on the sides of the citadel that the _Inflexible_ design was most freely criticized. Armour, except in the form of an under-water protective deck, was not used at all forward and aft of the citadel. The ends of the ship were left unprotected, but subdivided; the compartments near the water-line formed watertight tanks filled with coals, stores, or--next to the side of the ship--cork. This criticism was directed from two directions.

To many naval men the attempt to beat the gun by adding to the thickness of the armour was a game no longer worth the candle. The point of view, moreover, that the defensive power of a ship was accurately represented by the defensive power of an armour patch upon its side was condemned as altogether too partial and theoretical. The same fallacy was abroad in respect of guns. “Men were apt to think and speak as if the mounting of a single excessively heavy gun in a ship would make her exceptionally powerful, no matter what number of powerful, but still less powerful, guns were displaced to make room for it. The targets and guns at Shoeburyness were held to be real measures of the defensive and offensive powers of ships.”[170]

On the other hand, experience was at this time bringing to light the inefficiency of heavy naval artillery. In ’71 a paper by Captain Colomb attracted attention, in which he analysed the effective gun power of the _Monarch_, and showed, by the light of experiments carried out by her against a rock off Vigo in company with _Captain_ and _Hercules_, that “in six minutes from the opening of her fire on the sister ship at 1000 yards, she will have fired twelve shot, of which one will have hit and another may have glanced, and it remains an even chance whether the single hit will have penetrated the enemy’s armour.” In the following summer Mr. Barnaby was himself impressed with the difficulty which the _Hotspur_ experienced in hitting the turret of the _Glatton_ at a range of 200 yards in the smooth water of Portland Harbour: an experiment which, while confirming confidence in the reliability of a turret and its power to withstand shock, led him to question whether we were wise to put so much weight into the protection of turrets, and whether it might not be a better plan to stint armour on guns in order to add to their number and power.

From another direction the criticism was more directly effective. In ’75 Sir Edward Reed, now a private member of parliament, made a pronouncement on his return from a visit to Italy in the following words: “The Italian ships _Duilio_ and _Dandolo_ are exposed, in my opinion, beyond all doubt or question, to speedy destruction. I fear I can only express my apprehension that the Italians are pursuing a totally wrong course, and one which is likely to result in disaster.” The Italian Minister of Marine indignantly refuted the assertion, based as it must have been (he said) on incomplete information; and the construction of the _Duilio_ and the _Dandolo_ proceeded. But the remarks of the ex-Chief Constructor applied with equal force to the _Inflexible_; and in the following session he stated as much in the House of Commons. It was possible, he insisted, that in an action the cork and stores which filled the unarmoured ends of the _Inflexible_ might be shot away, and the ends riddled and water-logged; and that in such an event the citadel, though intact, would not have sufficient stability to save the ship from capsizing.

The reply of the Admiralty was to the effect that Sir Edward Reed had assumed an extreme case, and that such a complete destruction as he had envisaged was, even if possible, never likely to occur in a naval action.

The effect of both statements was to cause widespread anxiety in the public mind, and a lamentable loss of confidence in the projected warship. A decision was therefore made to appoint another Committee, of unquestioned eminence and freedom from bias, to investigate and report on the _Inflexible_ design. In due course the Committee reported. They confirmed in a long statement the Admiralty point of view that the complete penetration and water-logging of the unarmoured ends of the ship, and the blowing out of the whole of the stores and the cork by the action of shell fire, was a very highly improbable contingency; they found that the ship, if reduced to the extremest limit of instability likely to occur, viz. with her ends completely riddled and water-logged, but with the stores and cork remaining and adding buoyancy, would still possess a sufficient reserve both of buoyancy and of stability; and, balancing the vulnerability of the citadel with its 24-inch armour and the destructibility of the unarmoured ends, they came to the conclusion that the unarmoured ends were as well able as the armoured citadel to bear the part assigned to them in encountering the risks of naval warfare, and that therefore a just balance had been maintained in the design, so that out of a given set of conditions a good result had been obtained. Except that a recommendation was made that the system of cork chambers should be extended, no structural alteration from the existing design was proposed.

The _Inflexible_ was followed by its smaller derivatives, the _Ajax_ and _Agamemnon_, _Colossus_ and _Edinburgh_, and by the _Conqueror_, an improved _Rupert_, with a single turret. Movement was in the direction of smaller displacements and less armour; construction was influenced at this time more by Italian than by French practice.

§

All through this transitional decade, 1870-80, experience and various new developments were imperceptibly causing a gradual change of opinion as to what constituted the best type of battleship. At no period, perhaps, was the warship more obviously a compromise, at no time were the limitations of size and weight more keenly felt. So many considerations interacted with one another, so conflicting were the claims made of the naval architect, that it appeared indeed almost impossible to embody them in a satisfactory design. (And yet nothing is more remarkable than the unanimity with which designers, given certain conditions, arrived at the same final result: the _Duilio_ and the _Inflexible_ are a case in point.) Whatever the design might be, it was open to powerful criticism. And the chief part of this criticism was directed, as we have seen, against the use and disposition of the armour.