IN WHICH we trace the evolution of the turret ship in its first decades, from armored battery to self-propelled, oceangoing battleship.
Comparative drawings of the Coles and Ericsson turret systems, independently developed during the 1850s and mass-produced beginning 1860-1862 and well into the 1880s. The Ericsson turret -- named for its Swedish-born inventor -- predominated in the U.S., Russian, Danish, and Swedish navies, while the Coles turret, developed by Capt. Cowper Coles, RN, dominated in the British navy and British-built turret ships made for empire and export. Coles got his idea from improvised artillery barges constructed for Black Sea service during the Crimean War. These barges mounted guns on turntables for easy training by sight; outward-sloped parapets were added to the turntable sides to protect the gunners. Coincidentally, the first modern ironclad vessels were stationary batteries designed for French navy service in the same conflict, towed into position by tugs, and proved in battle at Kinburn, Crimea -- to the overstated glee of Emperor Napoléon III, who claimed the ironclad as his own invention. Napoléon's claims were not entirely fraudulent; he was a big promoter of the ironclad batteries, although the idea was not his originally; the history of protected ships can be traced back to Korea in its wars with the Mongol hordes in the 1590s. Its turtle ships had an array of octagonal, spiked metal shields overhead and patches of armor on the sides. More recently, Robert Fulton was an advocate of metal armor to protect his paddle wheels during the Napoleonic Wars, but settled for an 8-foot thick wooden hull. And in 1842 Hoboken's noted inventor Robert L. Stevens proposed a great ironclad steam battery for the defense of New York Harbor, shielded in 4½" iron. Begun with great hoopla in 1854, the Stevens Battery was abandoned 20 years later, not even close to completion, despite vast expenditures.
Given the growth of industrial technology and the long-running naval rivalry between the British and French, it was not surprising that the three innovations -- iron armor, steam propulsion, and the rotating gun turret -- were combined in experimental warships soon after the Crimean conflict concluded (1858). Ironclad frigates Warrior and La Gloire were laid down that year and completed in 1860-61; both had their armament disposed along the sides like traditional frigates, though with the greatly increased firepower of modern guns. The first ironclad turret ships were aleady on the ways when these pioneering ironclad frigates entered service, being commissioned in the British and U.S. navies in 1862.
Both Coles and Ericsson were classic 19th-century inventors, with egos to match and the necessary knack for self-promotion. Of the two, Ericsson (right) had the more abrasive personality. A Swede by birth, Ericsson had a long history with his Number One client, the U.S. Navy, going back to the 1840s and the experimental screw warship the Princeton. On one of this steam corvette's debut trips on the Potomac, a who's-who of naval brass and politicians embarked, including President John Tyler and his fiancée. A featured attraction was to be the test firing of the ship's two breech-loading shell guns: the Oregon, designed by Ericsson and manufactured in Britain, and the Peacemaker, incompetently designed by the politically connected Captain Stockton. After several successful trials, the Peacemaker exploded, killing and wounding several of the assembled dignitaries. Shamefully, the Navy exonerated Stockton and attempted to foist all the blame off on Ericsson, although the Oregon, rangefinders, and engines he had developed for the ship performed flawlessly.
Nor was this the end of the prewar "history". Ericsson sued the USN for multiple infringements of his patents, and won. After Fort Sumter, with news of Confederate ironclad-building ventures in the air, the inventor found a ready market for his inventions in Washington. But he encountered friction when he tried to rigorously control application of his turret in USN warships during the Civil War. Ericsson wanted to restrict deployment to single-turret installations -- in his view, the ideal deployment, since it provided an all-round training arc. Naval commanders retorted that two-turreted vessels would give twice the volume of shellfire and ensure battleworthiness even in the case of one turret's being knocked out in combat. Ericsson lost the argument. Many two-turreted ships were built for the USN, and even one with three turrets. However, the inventor could take comfort in being enriched by the war; he lived out his days in a U.S. grown indifferent to naval developments. His monitors were widely adopted in other navies, too, seeing use in the Danish, Russian, French and Swedish services.
Another fruit of American ingenuity was the Eads turret system, devised by St. Louis inventor James B. Eads, whose yards provided many of the best ironclads for the Union fleet. Although no drawings of the system are extant on the Web, it seems to have marked a quantum advance on the other turrets available at the time. Inside the armored cylinder, steam power was used to drop the guns and turntable to a lower deck for reloading; they were then returned to firing position and trained, also using steam power. Eads turrets were used in all four Winnebago class monitors. The Chickasaw's installation provided the rapid fire that pulped the Confederate ironclad Tennessee at Mobile Bay.
Specifications for the Winnebago class:
Dimensions: 226' x 57' x 6' Displacement: 970 tons. Armament: (4) 11" Dahlgren SB (2x2). Armor: Wrought-iron type; 3" belt, 8" turret, 1½" deck. Propulsion: Six coal-fired cylindrical boilers; (2) 2-cyl horizontal non-condensing steam engines geared to four screws. Speed: 9 knots. Complement: 123.
Ships in class: Milwaukee · Winnebago · Chickasaw · Kickapoo
Dimensions: 68.9m x 17.4m x 1.83m Displacement: 970 tons. Armament: (4) 279mm Dahlgren SB (2x2). Armor: Wrought-iron type; 76 mm belt, 254 mm turret, 38 mm deck. Propulsion: Six coal-fired cylindrical boilers; (2) 2-cyl horizontal non-condensing steam engines geared to four screws. Speed: 16.7 km/hr. Complement: 123.
A description of the Eads system:A Navy inspector, J.W. King, after examining the Eads turret on [the USS Winnebago], sent an enthusiastic report to Secretary Welles. This turret, he said, differed "in all respects from any heretofore constructed." Unlike the Ericsson model, it did not rest upon the deck and revolve about a central shaft, but extended, armored for some distance, below deck and revolved on spheres supported upon a circular box beam secured to the bottom of the vessel. The machinery performed a combination of functions with knowing ease that astonished him, revolving, reversing and regulating the motion of the turret; raising and lowering the platform containing the guns: moving the guns to firing positions and back again, reducing and cushioning the recoil, opening and closing the port. It was the first time in the history of artillery practice that heavy guns were manipulated entirely by steam.Like many a brilliant idea before and since, the Eads turrets were largely ignored by the USN and little more was heard of them as America turned its eyes toward settling the West and building a modern industrial economy. American turret ships would be based on the barbette-cum-gunhouse model adopted by Britain, when U.S. naval development revived in the 1890s.
"The design, construction, and arrangement of the details of the machinery is highly creditable to the ingenuity, mechanical skill and ability of the inventor ... who had to contend with all the disadvantages common to a light draft vessel," King wrote. Whether permission was given James Eads before or after this report, he finally had placed one of his turrets on each of three of the four large monitors, and had redesigned one of the Ericsson turrets on the fourth. [Florence L. Dorsey, Road to the Sea: The Story of James B. Eads and the Mississippi River (New York: Pelican, 1957), 81-82]
Coles had his own ideas about the application of of his turrets in an ironclad battleship -- ideas that were at variance with those of Sir Edward Reed, the Royal Navy's chief constructor. Reed built a large oceangoing ironclad with Coles turrets, HMS Monarch, in the late 1860s; commissioned 1868, the high-freeboard Monarch was considered a successful vessel and survived well past the year 1900 in a humble rôle. Coles preferred a more radical design, however, and cultivated influence in Parliament in support of his own contentions, resulting in the construction of a lower-riding turret ship, HMS Captain of 1870. This project was poorly managed and the engineering botched, due largely to Coles' own illness during construction. The resulting ship promptly proved fatal to the inventor and most of her crew, as you can appreciate from a close reading of BBB's HMS Captain article. The Captain disaster caused a major brouhaha and the British Admiralty called a temporary halt to new construction while the ironclad building programme was reasessed.
HMS Royal Sovereign, 1864 - First Four-Turret Ship  Photo
USS Roanoke - First Three-Turret Ship - Wooden Frigate Conversion
HMS Wivern - Ex-Confederate Turret Ship by Laird's, 1863
Peruvian/Chilean Ironclad Huáscar - Lairds Ironclad Export, 1865
The Affondatore - Thames-Built Turret Ram, 1866
Dutch Coast-Defense Ironclad Schorpioen - French-Built Turret Ram, 1868
HNLMS Buffel - Lairds-Built Turret Ram, 1868
HMS Monarch - Masted Turret Ship, 1868
HMS Captain - Experimental Masted Turret Ship, 1869
HMVS Cerberus - Pioneer Breastwork Ironclad, 1868
Turret Rams of the Royal Navy - 1870s-80s
HMS Devastation - The Shape of Things to Come, 1871
Turret Cutaway, HMS Devastation, 1871 - 12" Muzzle Loading Rifles
USS Monadnock and Later American Monitors: 20-Year Build Time
12" BLR Loading Video - HMS Colossus, 1885 - From Project Dreadnought
On the whole, the direction being followed by the Royal Navy was found by the Committee to be sound. Meanwhile, Reed resigned over the controversy, no doubt frustrated by attempts to blame him for the disaster, although he had warned all along of the unsoundness of Captain's design. Nathaniel Barnaby became acting DNC and later was confirmed as Reed's successor. In keeping with the findings of the Committee on Designs, an added emphasis on safety and seaworthiness was evident when building resumed. Additional freeboard was built into new ships nearly complete, e.g. HMS Devastation. The Coles turret remained the preferred type in the British Royal Navy through the 1870s and will be found in our Royal Navy pages in the many turret ironclads produced in that period.
As the most advanced country, Britain's influence extended over much of the rest of the world, since Britain built or furnished plans for ironclads in many other countries' fleets; at left, SMS Grosser Kurfürst of the Prussian navy, a wooden-hulled ironclad copy of HMS Monarch. It was by no means a given that the turret would be the predominant type of ironclad going forward, however. In this "Age of Uncertainty," the British and other navies hedged their bets by developing several different types of ironclad simultaneously -- battery ships, rams, échelon turret ships, and barbette ships, to say nothing of the various forms of torpedocraft developed to counter an adversaries' battle fleet. Most of the oceangoing ships in these categories still retained a towering sailing rig, making them high Steampunk concepts, favored by modelers and sci-fi fantasists today.
In the 1880s, British practice shifted to favor the barbette ship. Meanwhile, methods of lifting shells and charges into the turrets became much more elaborate. A common problem with turret ships in the 1870s and Eighties was the very slow rate of fire, the concomitant effect of the very complicated loading procedures for muzzle-loading guns (see the diagram for one of HMS Devastation's turrets, 1871). This was especially marked in the "Monster Gun" ships with a 16¼" or 17" armament. Some of these overgunned behemoths could only get off one round every five to fifteen minutes. As usual this was addressed with a technical fix. The beginnings of a solution came with the adoption of breech-loaders and electrically-powered hoists, bringing the rate of fire up to one every two to three minutes; a peak rate of fire for HMS Colossus in 1887, quoted by Rob Brassington, amounted to one round every 90 seconds, repeated six times in four minutes. But the placement of so much more machinery inside the turret, and running down the turret trunk, so greatly modified the internal structure that the mountings of, say, Colossus or the 1889 battleship HMS Nile could no longer be called true Coles turrets; although they did maintain the low-profile cylindrical shape of the original.
In order to reload, early breech-loading turrets still had to be trained to a fixed position, usually straight fore-and-aft. The final refinements came with the merging of the barbette with an armored gunhouse (c. 1895) and soon after, the invention of a flexible track hoist and revolving turret trunk, enabling continuous loading whatever the train of the turret ("all-round loading") in 1901. The success of this technology enabled the pre-dreadnought arms race and, within five years, the development of the dreadnought battleship.
Turret interior, monitor USS Passaic: Classic Ericsson turret design for U.S. Civil War monitor. The ship carried one Dahlgren 11" and one 15" in each turret; the guns could not fire simultaneously. In order to turn the turret, the entire assembly had to be jacked up, moved, and dropped on deck again, unlike the Coles turret, which turned on a roller bearing race. The Passaic class of ten monitors, completed late 1862, was the first to follow the prototype Monitor and closely followed the model of the original. The Imperial Russian Navy built ten identical copies of the Passaic, armed with Russian-made copies of the Dahlgren guns: the Hurricane class, completed 1864. The Russians rearmed these ships with rifled 9" Krupp guns in 1873; by then the U.S. had sold or scrapped most of its monitors, and had foresworn the pursuit of naval innovations. Monitor style warships remained popular for the rest of the century, principally for harbor defense due to their dubious seaworthiness; the British, Danish, Norwegian, Swedish, French, Ottoman Turkish, and Russian fleets all had sizable fleets.
Specifications for the Passaic class:
Dimensions: 201' x 46' x 11' Displacement: 1,653 tons std. Armament: (1) Dahlgren 11" and (1) Dahlgren 15" SB. Armor: Wrought iron type. 11" turret; 5"/3" hull sides; 1" deck, all built up from laminations of 2" and 1" plate. Propulsion: (2) coal-fired rectangular boilers; Ericsson vibrating lever engine, developing 460 IHP; single screw. Maximum speed: 6½ kts. Endurance: 1,400 nm @ 6 kts. Crew: 96.
The salvaged turret of the USS Monitor undergoing conservation at the Mariners Museum, Newport News, in 2011. The men are walking on the roof of the 149-year-old turret: the entire super-heavy assembly, with its foot-thick iron walls, was salvaged upside down as it sank. Held in place by gravity when on the surface, turret had lodged partway under the raftlike deck of the vessel when wreck hit the bottom. Guns were brought to the surface separately in a previous salvage operation. Enlarge (Photos: NOAA)
The old monitors were reactivated for an invasion scare during the Spanish-American War of 1898. Here a crew cleans the ancient guns aboard USS Nahant, named for a peninsular province of wealthy Boston Brahmins, singularly exposed to any surprise attack by "the Dons". Shot was taken at New York Navy Yard; cruiser USS New Orleans in background. This photo shows the armored flange covering the join of turret and deck; this was filled with rubber caulk whenever the ship went to sea. Enlarge
Above, breastwork monitor HMVS Cerberus: Pioneering turret ship was the first to raise a superstructure amidships (a "breastwork"), and the first seagoing turret ship with no sail rig -- innovations incorporated into the larger and more famous HMS Devastation immediately afterward, providing the immediate link to the armored ram and the pre-dreadnought battleship. Photo under the specs shows the remains of Cerberus in Half Moon Bay, near Victoria, Australia today; courtesy Glen Agnew. Ship had two twin Coles turrets mounting 10" muzzle loading rifles. For a free downloadable cardstock model of the Cerberus from Paper Shipwright, click here.
Specifications for the HMVS Ceberus:
Dimensions: 225' x 45'1" x 15'6" Displacement: 3,390 tons. Armament: (4) 10" RML and (2) 12-pdr howitzers; (4) 1" 4-barrel Nordenfelt MG. Armor: Wrought iron type. 10"/9" turret; 8"/6" belt (backed by 9"-11" of teak); breastwork 9"/8"; 1¼"/1" deck. Propulsion: (4) coal-fired rectangular boilers; (2) Maudslay horizontal return engines, developing 1,369 ihp; twin screw. Maximum speed: 9¾ kts. Service speed: 6 kts. Crew: 96 - 136.
Dimensions: 68.6 m x 13.7 m x 4.7 m Displacement: 3,390 tons. Armament: (4) 254 mm RML and (2) 12-pdr howitzers; (4) 4-barrel 105 mm Nordenfelt MG. Armor: Wrought iron type. 250/230 mm turret; 200/150 mm belt (backed by 230 - 280 mm of teak); breastwork 230/200 mm; 32/25 mm deck. Propulsion: (4) coal-fired rectangular boilers; (2) Maudslay & Field horizontal return engines, developing 1,021 kW; twin screw. Maximum speed: 18.1 km/hr. Service speed: 11 km/hr. Crew: 96 - 136.
Slightly smaller than the Cerberus, the Cyclops class followed the same basic design. Four were built as harbor defense ironclads during the War Scare with Russia in 1875. These ships, like their cousins the turret rams, were underutilized and spent most of their careers tied up alongside the dockyard wall.