The Development of Navies During the Last Half-Century/Chapter 4
CHAPTER IV
EARLY TURRET SHIPS
Introduction of the 'Monitor'—Claims of Ericsson and Captain Cowper Coles—'Merrimac' and 'Monitor' in America—'Royal Sovereign' converted in England—Further development of the Turret System—'Devastation' to 'Inflexible.'
Ericsson is generally credited with the first idea of mounting a gun in a revolving turret and placing it in a low iron-plated vessel, as practically applied in his celebrated 'Monitor' of the American Civil War. But Captain Cowper Coles, some years before, had been urging the adoption of the same system, and many of his original ideas are to be seen embodied in the ships of to-day. The plan with him seems to have originated in 1855, when during the Crimean War he mounted a 32-pounder on a raft, for service in the shallow waters of the Sea of Azof. This proving useful, he next thought of protecting the gun, and proposed an improved raft, formed of empty casks planked over, to carry a 68-pounder, pointing through an aperture in a hemispherical iron shield placed over it. He proposed a number of these rafts for an attack on Cronstadt. A committee of naval officers serving in the Black Sea reported favourably on the scheme, and Captain Coles was ordered home to lay his plans before the Admiralty. Peace, however, intervened, and nothing further was done. Captain Coles continued working out his ideas, and in June 1860 read a paper at the United Service Institution, in which he proposed a low freeboard vessel, on which were to be a number of cupolas or turrets, such as he had devised for the improved raft, each containing two guns; the space required for a pair of guns being little more than that necessary for a single piece. But now follows the principal feature of his system. Hitherto changing the direction of a gun was effected roughly and laboriously by tackles and handspikes. Captain Coles' proposal is thus described in his own words: 'The horizontal motion or training is effected by turning the shield itself, with the gun, crew, and the platform on which they stand. The whole apparatus thus becomes, as it were, the gun carriage, and being placed on a common turntable, can be revolved to the greatest nicety of adjustment by means of a winch.' The idea of a turntable he no doubt took from the arrangement of the railway system. As all heavy guns are now mounted on turntables, and revolve either with the shield, as in case of turrets, or independently, as in the case of ship barbettes, we must recognise the claim of Captain Coles to be the inventor of the modern system. The 'Monitor' was not built until two years afterwards.
Our Government, however, had decided upon the 'Warrior' type, and were not disposed to try an experiment in quite a different direction. Nor were the continental powers so inclined. The broadsid 
There was great consternation in the North at this event, but the means were at hand to arrest the Southern vessel in her triumphant career.
In August 1861 the Northern States had determined to obtain ironclad steam vessels, and at the end of that month Ericsson offered to construct in a few months a vessel which would destroy the rebel squadron. A board of officers was appointed to consider plans proposed, and in September it recommended that a vessel on Ericsson's design should be built. She was commenced in October, launched on January 30th, 1862, and completed on February 15th, 1862. The design provided for a hull not more than 2 ft. above the water, and with a flat bottom, that the draught might not exceed 10 ft. The sides, to a short distance below the water line, were protected with 4-in. plates. In the centre of the deck was built a circular turret, revolving on a central spindle, and protected with 8 in. of iron. Inside the turret were mounted two 11-in. smooth bore guns, pointing through port holes. They could thus fire in any direction without turning the vessel, an obvious advantage not only on the open sea but especially in narrow waters, for which she was more intended. Such was the famous 'Monitor,' a name given by Ericsson to his creation to admonish the leaders of the Southern Rebellion, and to be also a monitor to the Lords of the Admiralty in England, suggesting to them doubts as to the propriety of their building four broadside ironclads at three and
ERICSSON'S TURRET.
a hall million dollars each. Such were the reasons given by Ericsson himself for the choice of this name. He had not forgotten his unsuccessful attempts to favourably impress their lordships with his screw propeller twenty-four years previously.
We have seen that on March 8th, 1862, the 'Merrimac' had sunk the 'Cumberland.' On March 2d the ' Monitor' left New York under the command of Lieutenant Worden, and after a somewhat stormy passage she arrived at Hampton Roads on the evening of the 8th. The next morning when the 'Merrimac' appeared again, bent on destruction, those on board descried a strange-looking object, an iron tower, apparently, on the surface of the water. Then the low hull was made out, and a dash made for this new opponent. The battle then began, but it was soon apparent that the 'Merrimac's' ordnance could make no impression on the turret of the 'Monitor,' and there was little else to hit. The casemate of the 'Merrimac,' however, offered a good mark, and almost every shot of the other took effect somewhere. After two hours' pounding the 'Merrimac' hauled out of action, having sustained considerable injury, and, owing to orders previously given, the ’Monitor' allowed her to depart. But the principal object had been gained, and the 'Merrimac' gave no further trouble. The 'Monitor' was struck twenty times, of which nine hits were on the turret, but the injury done was trifling. Great rejoicings took place throughout the North at this event, and it was believed this new method of naval construction would supersede all others. It certainly exercised a powerful influence in more than one country.
But an essential quality was lacking in the 'Monitor,'—seaworthiness. Steaming against a moderate wind and sea, the water swept over her like a deluge, and found its way down the funnels and any aperture leading to the interior. A few months after her encounter with the 'Merrimac' she foundered in a gale off Cape Hatteras. In England it was evident that a type of vessel unfit for distant service could not serve as a model for general adoption. But as coast defence was then prominently before the country, owing to the views expressed by Lord Palmerston when proposing in 1860 a large outlay on sea forts, it was decided to construct two turret ships on Captain Coles' plans. A wooden three-decker, the 'Royal Sovereign,' was accordingly cut down and armoured with 5½-in. iron
THE 'ROYAL SOVEREIGN.'
Captain Coles, however, considered that a seagoing turret ship was perfectly feasible, and persistently advocated the principle. As he was supported by the press, the Admiralty decided to build a masted turret ship, and the 'Monarch' was commenced. As she did not embody the views of Captain Coles, he was at length permitted to build a vessel of his own design, and he entrusted the work to Messrs Laird of Liverpool. Guns having increased so much in weight it became necessary to limit the number of turrets to a pair placed on the centre line of the ship, 120 ft. apart, each containing a pair of guns. There were three masts, on the tripod principle, by which the necessity for rigging is dispensed with, and she was given full sail power. It is unnecessary to go into further details, because this unfortunate vessel, which was named the 'Captain,' was lost, with nearly all hands, on September 6th, 1870. She capsized in a heavy squall off Cape Finisterre when under sail. Captain Burgoyne was in command of her, while Captain Coles was his guest, desirous of observing the behaviour of his design at sea. The loss of two such men, with the remaining officers and crew, was a national disaster not likely to be forgotten. Errors of construction caused the catastrophe, combined with the great leverage exerted by the sails when struck by a heavy squall.
Loss of the 'Captain' and the principal advocate of masted turret ships led the Admiralty to abandon this type, but the 'Monarch' was completed, and remains the solitary specimen in our navy. She was similar in general design to the 'Captain,' but in many important respects the two ships differed widely. The sides of the 'Monarch' were 14 ft. above the water, whereas in the 'Captain' they were only 6 ft. In the original design of the latter they were to have been 8 ft., but additional weights placed in the ship reduced this by 2 ft. The two turrets of the 'Monarch' were closer together, the lower portion of them being protected by the side armour above the belt, which was carried up for this purpose. The thickness here was 7 in., while the turrets were given 10 in. of armour. In each was mounted a pair of 25-ton guns, the largest ordnance then in use. As the masts obstructed the right ahead and astern fire smaller guns were placed at the ends of the vessel. All this was accomplished on a displacement of 8350 tons, and produced a powerful fighting machine, but the sailing capacity was indifferent. In fact it was becoming recognised that the gain in one respect was a loss in another, and that the turret system suffered if combined with a large spread of canvas. The advantage of turrets was the large arc of training they enabled guns to cover on either side of the ship, and that the whole of the armament was brought into play instead of only half, as in the case of a broadside ship. But if masts and their rigging were given to such ships, as in the case of the 'Monarch,' this arc was much circumscribed, and the full benefit of the system was not reaped.
It was therefore determined to build turret ships for extended sea service without this objectionable feature. Locomotion was to depend wholly on steam and two screws with separate engines gave a double chance against a total breakdown. To make up for the absence of sail power, the supply of fuel must be increased. This led to the design of the 'Devastation,' and as she was the first mastless seagoing turret ship we built, her construction excited considerable interest. The leading features were a low freeboard hull, carrying two turrets, on the middle line of the ship. To protect the base of the turrets an armoured breastwork or citadel was built round them. This did not extend right across
THE 'DEVASTATION.'
the vessel, so that there was a space between the walls of the breastwork and the ship's side. At the instance of a committee appointed after the loss of the 'Captain' to consider designs, this space was enclosed by carrying up the side of the vessel to the height of the breastwork and extending the deck over the latter to meet the raised portion. This addition to the side, though not armoured, increased the freeboard of the ship in the central portion to over 10 ft., while right aft it was only 4 ft., and forward there was a low forecastle 8 ft. above the water. The armour on the side extended right round, and was 12 in. thick amidships, tapering to 10 in. at bow and stern. On the turrets it was 14 in. It was at first intended to mount in these four 25-ton guns similar to those of the 'Monarch,' but we had now reached ordnance of 35 tons, and a pair of these 'infants,' as they had been ironically termed, were allotted to each of the 'Devastation's' turrets. She was given twin screws, worked by separate engines, and a coal stowage provided for 1300 tons. This capacity was largely in excess of that of all previous ships, and forms one of the most valuable features of this class. When it is considered what was done with dimensions—9350 tons—just under those of the 'Alexandra,' that the total weight of protection carried was 2950 tons of iron and wood, or an increase of 600 tons over the broadside ship, and that she could present on either side a concentrated fire of four 35-ton guns, while the range ahead or astern was covered by two such pieces, all efficiently protected, it may be conceded that the success of the turret system had been proved. But what a change from the three-decker of 120 guns to the 'Warrior' of forty, and thence to the 'Devastation,' with only four heavy guns. Could the principle of concentration of armament be extended further? The limits were not yet reached. The 'Devastation' was completed in 1873, and any doubts that may have been felt as to her seaworthy qualities were speedily set at rest. She proved able to encounter severe weather, and wonderfully steady in a heavy sea. The sea washed over her like a half-tide rock, but with apertures closed it could not find its way below. There was, of course, discomfort to the crew, who were dependent on artificial ventilation, but for service in the Mediterranean, where bad weather is of short duration, this class of ship has proved well suited.
The 'Dreadnought' was the next improvement. A slight increase in the thickness of the armour and weight of the armament involved an additional displacement of 1500 tons. There were also structural differences of some importance, which entailed extra weight. The armoured breastwork extended right across the ship, and was 186 ft. long, instead of 154 ft. in the 'Devastation.' A higher freeboard throughout was also given. She had four 38-ton guns, which, owing to improvements in ammunition, were considerably more effective than the 35-ton guns. With these modifications the 'Dreadnought' was, and is to this day, regarded as an excellent type of fighting ship. After a departure of some years, we again returned to the general principle of her construction in the 'Nile' and 'Trafalgar,' to which allusion will be made later on.
Though we had, without unduly increasing the size of the battle ship, passed from 4½ in. to 14 in. of protective armour, the power of the gun had more than kept pace, and it was evident that if armour capable of resisting the heaviest ordnance was applied to a ship the area covered by it must be contracted, or we should be compelled to resort to enormous ships. At that time it was considered undesirable to exceed 12,000 tons. Not only had the resistance of the structure to hostile shot to be considered, but the power to strike heavy blows in return was even more important. Artillerists were, with improved plant, constructing heavier guns than the 38-ton, and we were not prepared to view with equanimity foreign vessels with an advantage over ours in this respect. The outcome of such views was the 'Inflexible,' designed by Mr Barnaby, then Chief Constructor of the Navy. In her the armour at the side only extended for a length of 110 ft., in the centre of the vessel, so that the complete armoured belt was abandoned. This was the principal innovation, which led to
THE 'INFLEXIBLE.'
much controversy at the time. There was a breastwork or citadel, as in the 'Dreadnought,' the whole breadth of the ship, which was increased to 74 ft., a remarkable amount of beam for a length of 320 ft. In the 'Monarch' the proportions were 330 by 58. By thus contracting the citadel of the 'Inflexible' to 110 ft. it was possible to protect the sides with 24 in. of iron, disposed in two thicknesses of 12 in. each, with a layer of wood backing between. Diagonally across the citadel, and within its walls, were placed two turrets, each armed with a pair of 80-ton guns, such a bound had ordnance made since the days of the 'infants.' This arrangement of the turrets was to allow all four guns to point directly ahead or astern, whereas if placed on the fore and aft line, as in previous ships, only half the armament could be so utilised. The turrets were protected with 16 in. of armour, consisting of a wrought-iron plate of 7 in., and
SECTION THROUGH TURRET OF THE 'INFLEXIBLE.'
When turrets were first introduced steam was employed to rotate them, and also, as the guns increased in weight, for many of the operations connected with their manipulation. But steam has the disadvantage of condensation in pipes when transmitted, and for such a delicate manœuvre as keeping the sights of a gun on a mark, which was effected by small movements of the turret, steam power has defects. Hydraulic power was therefore devised by Sir William Armstrong and Mr G. Rendel, of the Elswick firm, to perform all these operations, and applied in the ’Inflexible' with great success. The heavy turrets could be rapidly swung round or rotated with almost imperceptible motion, and stopped dead at any required moment.
From the day on which we had begun to construct warships of iron it became necessary to guard against injury in the event of such a vessel striking the ground or rock. A wooden ship might do this and suffer little damage or danger of foundering, as the material, being more elastic, had a tendency to close in over the fractured part, and swell as it became sodden with water. Iron did not possess this advantage, and, moreover, to give the requisite buoyancy the submerged portion of the hull must necessarily be thin, so that injury was easily inflicted in this part. Even at the slowest speed the momentum of a weight of 9000 tons coming in contact with a rock would crush in the fragile shell like matchwood. To meet this the double bottom was devised, which consisted in having an inner iron skin a short distance from the outer bottom. In case of the latter being punctured, the inner skin would prevent an influx of water to the interior of the ship. This was first carried out in the 'Warrior,' but the dual portion only extended 11 ft. on each side of the keel. In succeeding ships this principle was developed, and the inner skin became a veritable second hull under water, the space between the two being increased and sub-divided into a number of cells. This cellular sub-division was adopted with the view not only of giving strength in case of striking the ground, but also of reducing the effect of a torpedo explosion under water. As it was impossible to place armour here, the double bottom was a substitute, the hope being that the inner skin would be intact after the outer hull had been driven in by the explosion. As against the blow delivered by a ram such a protection would be insufficient. The only safeguard is to divide the interior of the vessel into watertight compartments, so as to confine the water which would rush in when both skins were fractured to that particular locality. This principle had been carried out in greater degree with succeeding ships, so that the 'Inflexible' had 127 of these compartments. Each is provided with a watertight door, to allow free access to all parts at ordinary times, and these, of course, must be a source of weakness to the principle. They may not be closed at the proper time, and are liable to get out of order unless continually worked.
Although the difference in weight between four 38-ton guns and the same number of 80-ton guns, including the carriages on which they are mounted, does not exceed 200 or 300 tons, it is in the ammunition that a heavier armament makes so much difference. We had arrived at projectiles weighing nearly a ton each, with a charge of some hundreds of pounds of powder. To provide, therefore, say a hundred rounds for each gun, or even a smaller number, involved a great addition of weight. Hence the dimensions of the 'Inflexible' and her equipment increased the displacement to 11,600 tons—the largest warship we had constructed. The design was not to pass unchallenged. Grave doubts were expressed by a high authority as to the wisdom of leaving the ends unprotected, and as to the stability of the vessel when these had been subjected to a heavy shell fire. The extremities were guarded only by an armoured deck 3 in. thick just below the water line, and at the sides by spaces filled with cork, to give buoyancy when this part was perforated by shot and water gained admittance. A committee, however, of distinguished men appointed to investigate the design did not consider that the ship would be specially liable to such a disaster. The question really hinged upon the amount of fire a ship is likely to receive in action in any particular part, and experience teaches us that, under such conditions, no one portion is more liable than another. The 'Inflexible,' therefore, was completed, and in 1882 assisted in the bombardment of the Egyptian forts with the 'Alexandra,' each representing a system and its development in twenty years. A brief review of this important operation as the first serious bombardment by an ironclad squadron may be of interest.
There has been rather a tendency to depreciate this engagement by dwelling on the weakness of the defence. Much is made of the fact that no submarine mines were used to keep the ships at a distance, that the guns on shore were weak and badly served, and that under totally different conditions the fleet could not have succeeded. It seems unnecessary to discuss what might have been, or we could reply that no special arrangements had been made on the side of the attack, no mortars provided, and the ships that took part were not all the most powerful we possessed. The fact, however, remains that the batteries were silenced, and the guns deserted, showing that the admiral in command had accurately estimated the force necessary to produce this result. But these batteries may well have been considered as formidable. About twelve in number, they were distributed along the coast commanding the approach to Alexandria Harbour. They mounted over 200 guns, of which about forty were rifled, while the remainder were smooth bores. Except for the penetration of armour, the latter were capable of inflicting heavy damage on the assailants.
The attack was to be made by eight armoured ships, carrying less than 100 guns so arranged that in many cases only one side could be brought to bear at a time. That some of the guns threw projectiles infinitely larger than could be returned from the shore did not give a corresponding advantage to the ships, because it has usually been found that number, rapidity of fire, and moderate size tells most against fortifications. Every hole and cranny is then found out, to the discomfiture of the garrison.
The ships opened fire early on the morning of July 11th, 1882, at ranges varying from 1500 to 4000 yards. The fire was returned from the forts, but the ships being mostly under weigh were difficult to hit. This also affected the accuracy of their own fire, so that eventually they anchored and continued a heavy cannonade upon such forts as were still working their guns. Some were silenced about half-past ten, and this released some of the ships to devote their fire to other forts. At three o'clock fire had ceased from the shore. No great damage had been inflicted on the ships. The 'Alexandra' had suffered most. She was hit about thirty times, but mostly by round shot. About forty more hits were distributed among the remaining ships, and the total number of casualties was six killed and twenty-five wounded. The casualties on shore could not be ascertained, but they were probably heavy. The fire of the ships was accurate on the whole, but the fuses being defective, many of the shell did not burst. Several of the guns on shore were dismounted or disabled, but the works behind which they fought were not greatly damaged. This was owing to the small number of guns that could be opposed to them. The guns were silenced chiefly by projectiles entering the embrasures. In such operations vessels carrying a large number of moderate sized guns will be more effective than ships carrying monster ordnance few in number. For the attack of forts high angle fire from mortars and howitzers is very effective, but no provision for vessels so equipped is made in our fleet. To do the same work with direct fire would necessitate a numerical superiority in guns, such as existed in the days of 100-gun ships.