The guns of the Napoleonic Wars, those mounted on board the earliest cruisers in this book, were smoth-bore muzzle-loaders, typically 18- , 24-, 32- and 42-pounders. Line-of-battle ships typically mounted 32pdrs on the gun deck and 18- or 24pdrs on the upper deck(s), plus short carronades (24- or 32-pdrs).26 The first proposals for a uniform armament of 32pdrs (with shorter guns on the upper deck to save weight) came in the 1820s. The standard early nineteenth-century cast-iron 32pdr was 9ft 6in long and weighed 55cwt 2qr [quarters]. Beginning in 1830 many guns were bored out to 32pdr calibre (6.25in); some ships were rearmed. New types of 32pdr were being developed.27
Apart from carronades, these guns were all mounted on wheeled trucks, the entire truck recoiling with the gun. There were no fixed mountings. Ships’ sides generally had gun ports cut into them, and guns were placed at the ports. Chasers (guns firing right ahead and astern, used when the ship was in chase or being chased) were placed at bow or stern ports, but were not fixed there. In some cases guns were wheeled from broadside positions to act as chasers. Chasers are sometimes described as pivot guns. That generally meant guns on slide mountings pivoted at one end, the gun recoiling along the slide. Typically the slide had rollers running along fixed deck racers. Most chasers of 64pdr size and below were on trucks which could be rolled to fire from ports in the bow or stern. This type of mounting made it simple to rearm ships; until ships had mountings built into them, armaments were hardly permanent. Needing less space to recoil, carronades were typically mounted on slides pivoted to the deck.
There was considerable interest in heavier solid-shot guns, but they required larger crews to manhandle them, and these extra men in turn crowded gun decks. The Royal Navy standardized on 32pdr solid-shot guns, with the sole exception of the 68pdr 95cwt (8in) gun introduced by Colonel Dundas, which was adopted in 1838. The 68pdr also became the Royal Navy’s standard shell gun, firing a 51lb shell or a 56lb plugged solid shot. It was generally used as a chaser, but by the 1840s some ships mounted only 68pdrs on their gun decks.28
In the 1850s the argument about manpower was turned around. With men somewhat scarce, it was argued that ships should mount fewer heavier guns, all 68pdrs if possible. On this basis a large frigate (with a single gun deck) might be as powerful as a three-deck ship of the line armed entirely with 32pdrs and carronades.
Intense interest in large-calibre shell-firing guns dated back to proposals by French artillery officer Henri-Joseph Paixhans published in 1821-22.29 Many agreed with him that shell guns could burn out or shatter wooden warships, which in the past had been able to absorb considerable damage from heavy solid shot (that is why so few large ships were sunk by gunfire during the age of sail). In 1839 the Admiralty decided to place shell guns on board thirty ships of the line and forty frigates. In addition to the 68pdr, the Royal Navy later adopted a 10in gun which fired only shells (84lb projectiles).30 Armour was adopted largely to solve the shell problem, although in retrospect it is not clear how destructive shellfire really was.31
A 40pdr Armstrong breech-loader on a truck mounting on board the screw frigate HMS Narcissus (the standing officer obscures the breech). In battery the gun was lashed to the side of the ship, as shown, but the carriage could be wheeled to a bow or stern port. The 40pdr (4.75in) weighed 1 ton 15cwt (35cwt) and was 10ft 1in long (its bore was 22.39 calibres long); it fired a 40lb shell at 1160ft/sec. There was also a 20pdr breech-loader for sloops and for boats (3.75in calibre, muzzle velocity 1000ft/sec, bore 54in long, 15cwt; 13cwt for boats). The initial main deck battery of Narcissus was twenty-two 32pdr and eight 8in 65cwt shell guns. On her upper deck were one 68pdr 95cwt chaser on a pivoted slide plus two 8in shell guns and eighteen 32pdrs. All of these weapons were smooth-bores, but soon Armstrong breech-loaders like this one were available (the 40pdr was officially adopted in 1859). Apparently one 7in (110pdr) breech-loader replaced the chaser and eight 40pdrs replaced the other upper deck guns. Notes on the 1857 plan for the ship suggest that 110pdrs replaced the main deck 32pdrs (the numbers are not known and it is not certain the planned changes occurred). In November 1864 Controller Rear Admiral Robinson listed Narcissus among the first ships to be given the new 64pdr muzzle-loading rifled guns, 150 of which would soon be available. As refitted, the ship’s main deck battery was fourteen 8in shell guns and the twelve 64pdrs. Aurora and Liverpool were first in priority for rearmament (12 guns each). Of the others, Narcissus was seventh. The remainder, in priority order (number of guns in parentheses), were: Cadmus (8), Arethusa (12), Constance (12), Scout (8), Bristol (12), Octavia (12), Challenger (8), Jason (8), Satellite (8), Undaunted (12), Immortalite (12), and Topaze (12), a total of 160. In 1865 a list of ships to have the new 6½-ton (7in) muzzle-loader included three screw frigates, each with four of them: Mersey, Orlando, and Endymion. Later the Amazon class screw sloops were added. On commissioning (20 December 1860) Narcissus joined the Cape of Good Hope station; in April 1865 she became flagship of the South East Coast of America (South America) station. Beginning in December 1870 she was flagship of the Detached (Flying) Squadron, described alternatively as a training squadron and as an attempt to replace the deployed units on different stations. She ended this service in May 1877. Narcissus was reduced to coast guard service at Greenock on 20 July 1877, paying off on 8 May 1878.
(National Maritime Museum A7807-019)
An Armstrong 7in 110pdr breech-loader on board HMS Narcissus. The gas seal consisted of the steel vent-piece (inserted from the top of the gun) screwed tight by the two handles (shell and charge were inserted through the opening between the handles). In action it was not always possible to be sure that the handles were tight enough, and vent-pieces sometimes flew out. The Armstrong breech-loaders, particularly the 110pdr, gained a bad reputation after Vice Admiral Kuper’s squadron shelled Kagoshima on 14 August 1863: 21 Armstrong guns suffered 28 accidents while firing 365 rounds. The lead coating of their shells fouled the rifling, rendering them inaccurate. The 110pdr was officially withdrawn early in 1864, to be replaced by the lighter muzzle-loading 64pdr rifle, but some ships still had them as late as 1872 (by 1874 they were gone). In 1872 data for the 7in breech-loader were: weight 4 tons 2cwt (82cwt), overall length 10ft, projectile 90½lbs, muzzle velocity with maximum charge 1125ft/sec. Comparable data for the 7in muzzle-loader were: weight 130cwt, extreme length 11ft, bore 15.88 calibres, projectile weight 115lbs, muzzle velocity 1325 ft/sec. There were two different types of 64pdr, Mk I (71cwt) being a conversion of an existing 68pdr smooth-bore and Mk III (64 cwt) newly-built (Mk II was not used). Both versions were 6.3in calibre. Mk I was 10ft 2.72in long (bore was 16.42 calibres long) and had a muzzle velocity of 1260ft/sec with a full charge. Mk III was 9ft 10in long (bore was 15.47 calibres long) and had a muzzle velocity of 1390ft/sec with its heavier full charge (10 vs 8¼lbs). The true replacement for the 110pdr was the 7in rifled muzzle-loader (6½ tons or 130cwt; after 1872 there was also a 90cwt cruiser version). Guns like the 110pdr could not handle charges as great as those of contemporary muzzle-loaders because their breeches could not withstand as much pressure. Before about 1880 powder burned quickly, so a gun gained little or nothing from having a longer barrel (the longer the barrel, the more friction slowed the shell passing from it). The later slow-burning powders reversed the situation, since it took a long barrel to make full use of the available energy. According to the 1885 gunnery manual, the need for long barrels became clear in 1873-79. They could not be muzzle-loaders because long guns could not be run back far enough into a ship to be reloaded at the muzzle. That was quite apart from the lesson of the explosion of an accidentally double-loaded muzzle-loader on board HMS Thunderer.
(National Maritime Museum A7807-011)
Quite aside from improved guns, the Royal Navy of the 1830s and 1840s benefited from systematic improvement in gunnery. The naval gunnery school HMS Excellent was established at Portsmouth in 1830; its improvements were evident during the Syrian crisis of 1840, which was also the first important operational use of British steam warships. In addition to training British gunners, Excellent was in effect the