The ‘True Frigate’ 1748-1778 Part III

A more detailed model, again thought to represent Minerva, which is certainly what was intended, but it presents a few oddities. The quarterdeck rails correspond with the earliest draught and the figurehead, allowing for the loss of limbs, is close to that shown on a later draught. The waist rails have been raised, as occurred while Minerva was on the stocks (although the gangways are not quite flush as in the other model, which was a slightly later modification), but the most noticeable departure from the known features of the full-size ship are the oar ports. These can be seen on the later ships of the class, but not the parallel Williams design for Latona, nor on any draught for Minerva.

The Heavy Frigate 1778-1815

In an exchange of correspondence between the Admiralty and the Navy Board in October 1778, the Navy’s administrators quietly ditched a century-old, though largely unspoken, precedent. It had always been believed that any significant increase in the size, and hence cost, of warships was not in the national interest; this had manifested itself not only in the building of the smallest viable ships of each rate, but also an unwillingness to promote any new type, like the 74 or the 12pdr frigate, which promised to be more expensive to build, operate and man. This reluctance was only ever overcome when the irrefutable evidence of war proved that British ships were so inferior in firepower or performance that fundamental improvements were essential.

On 21 October the Admiralty told the Navy Board that it was to propose no more small frigates under 32 guns but, on the contrary, it should consider more powerful ships of 36 or 38 guns with a main battery of twenty-eight 12pdrs. France was now in the war and her navy already had such ships, so the Admiralty, led by the experienced and highly competent Lord Sandwich, was responding in traditional fashion to a known threat. It was no part of the Navy Board’s remit to make policy, but on the 29th they replied with a radical proposal to build the 36- and 38-gun ships with scantlings strong enough to carry 18pdrs: ‘Such ships we conceive will exceed in strength any now possessed by the French and may be constructed with every advantage that such ships ought to have.’ Their letter was accompanied by draughts for an 869-ton 36 by Sir John Williams and an even larger 938-ton 38 by Sir Edward Hunt.

After some deliberation the Admiralty ordered one 36 to be called Flora and one 38 which became Minerva: for the first time in the eighteenth century, the Royal Navy took the initiative in introducing a far larger and more expensive ship-type. The step-change was substantial. At a time when there was hardly a British-built frigate exceeding 700 tons, these new ships represented a huge escalation – the 36s typically cost nearly 40 per cent more than a 12pdr 32, but the 38s were almost twice as expensive; on the other hand, the 36-gun ship offered 52 per cent more firepower in broadside weight of metal and 62 per cent for the 38. They would not be built in large numbers, but for the first few years of their existence they had no equals in any other navy. They were highly regarded ships, and their entrance into service caused quite a stir – especially the 38s, which may be why there are a number of excellent contemporary models of them (apart from the two shown here, there is superb representation of Minerva, shown fully coppered, at Annapolis; and a model of Arethusa at Bristol, unplanked on one side revealing all the interior structure).

As had become the norm since Anson’s day, each Surveyor produced a comparable design, Williams’ 38-gun draught being adopted for the one-off Latona, and Hunt designing a 36 which became the four-ship Perseverance class, built alongside the four of Williams’ Flora class. It was not to be expected that such innovative designs would be perfect at the first attempt – indeed, the Minerva seems to have been draughted in a hurry and Hunt modified the lines of the three that followed. The main problems surrounded the size and weight of the 18pdr. The 141ft gundeck of the 38s was hardly long enough for fourteen ports a side – carrying guns so far forward and aft made them prone to heavy pitching – while the 9ft 4lcwt guns were unwieldy. The latter problem was solved by designing a new 8ft 38cwt gun for frigates, and the last Minerva class ship, Melampus, was converted to a 36 during construction with only thirteen upper deck ports that were rearranged to keep them away from the extremities of the ship. She turned out to be the best sailer of the first generation 18pdr ships (there is a fine rigged model of the ship alongside the aforementioned Arethusa in the Bristol City Museum).

The two 36-gun designs were very similar in performance, and with 6 inches more between the gunports than the 38s, they were less cramped. However, the battery also stretched almost to the ends of the ship, and they were given rather full lines and a deep hull to compensate. This made them weatherly, good sea-boats and – being short – manoeuvrable, but they were not very fast by frigate standards. Nevertheless, the Perseverance class was well enough thought of that the design was revived in 1801.


Much has been made of the superiority of the French ‘scientific’ attitude to shipbuilding; far less of the advantages of British technology to the Royal Navy. The French claimed to be the first to be able to predict a ship’s stability mathematically, for example, but a class of 74s designed as late as 1778 proved their calculations hopelessly wrong; at precisely the same time the British were perfecting two innovations which were to prove of almost incalculable importance to the coming war effort. One was copper sheathing and the other was the carronade.

Ever since ships had gone to sea, the growth of weed and encrustation on the underwater hull – fouling – had been a problem, as it significantly retarded the progress of the ship through the water (for vessels of this era it could mean the difference of 2 or 3 knots). In warmer waters wooden hulls were also threatened by the Teredo navalis mollusc which bored along the lengths of timbers, potentially weakening them to catastrophic effect. The conventional remedy to both hazards was to cover the ship’s bottom with either some primitive forerunner of antifouling paint, usually highly toxic, plus a sheathing of thin ‘sacrificial’ planking intended to keep the Teredo from the main hull.

A close-up of the bow of the Minerva model at the US Naval Academy in Annapolis. The coppering on this superb model is entirely to scale.

These were such fundamental problems that many unsuccessful alternatives had been tried over the centuries, but in 1761 the British sheathed the frigate Alarm in thin copper sheets. Galvanic action soon corroded the ironwork used to fasten the underwater hull, but although nobody understood the science, the British persisted with practical trial-and-error experiments until by 1778 they had a workable solution. A systematic scheme of coppering line of battle ships was put in hand in February 1779 and in the following May all frigates were ordered to follow suit. By 1781 half the battlefleet was coppered, along with 115 frigates and 182 smaller ships.

Coppered ships proved to have a huge tactical advantage – they were not only faster, but also ‘fouled’ more slowly, so retaining their speed advantage longer. Henceforth, any small superiority in sailing bestowed by a finer (but unsheathed) hull form would be more than cancelled out by the reduced frictional resistance of a copper bottom. Moreover, the coppered navy gained a massive strategic benefit in extended periods between dockings, in effect multiplying the number of ships it could have in service at any one time. Fighting not only the colonial rebels, but France, Spain (from 1779) and the Netherlands (from 1780), it is difficult to see how a vastly outnumbered Royal Navy could have coped without this trump card.

Having given the fleet a speed advantage, the Navy Board was simultaneously working towards enhanced firepower. Key to this was a new lightweight, short-barrelled weapon, capable of rapid fire but handled by a small crew. Developed by the Carron Foundry in Scotland and christened the carronade, it was intended originally to allow short-handed merchant ships to defend themselves against privateers, whose favoured tactic was to board in order to do as little damage as possible to their prize. In these circumstances the gun’s major drawback – its short range – was less relevant.

The carronade’s origins are obscure but its very short length may have been inspired by the howitzer and existing swivel guns may have played a part – early versions were mounted in a similar fashion, on crutches, and some had a ‘tiller’ for aiming. At first they had trunnions like conventional cannon [SLR2966], but their development was rapid, particularly in the mounting as this was the most important contributor to its speed and ease of handling. Eventually, a pivoted slide mount became the preferred fitting.

In 1778 the carronade received the enthusiastic backing of the Navy’s administrators, who saw its potential for anti-personnel fire and dismantling rigging. It was to be a supplementary weapon not a substitute, filling empty spaces on the upperworks, and frigates with their long and lightly armed quarter decks and forecastles became the prime beneficiaries. There were teething troubles, particularly with muzzle-flash, which endangered the crew and – because the barrel did not protrude very far through the port – the lower rigging. The answer was to lengthen the barrel and later to add a muzzle extension, but the bulwarks were also planked up solid to protect the crew.

Service reaction was mixed at first, but by the end of the war a number of high-profile successes for the carronade had swung Navy opinion in its favour. They were all removed for peacetime commissions after 1783, so they were still seen as supernumerary weapons, but by the time war was again underway in 1794, the proposed additions for frigates were of far heavier calibre – 32pdrs for 38s and 36s, with 24pdrs for smaller frigates. At first carronades were entirely additional and, like the swivels they in effect replaced, they were not counted in the rating, but soon the huge advantage of a 32pdr or 24pdr weapon over the usual long 9s or 6s led to the replacement of conventional guns with carronades. By about 1800 most frigates had only two long guns as chasers on their upperworks and all remaining ports filled with carronades – but the traditional rating remained, so a British ‘38’ regularly mounted 46 guns.

The mature form of the carronade and its mounting. The gun has a muzzle cup (extension), the trunnions have been replaced by loops underneath, and elevation is via a screw mechanism at the breech. The body of the carriage recoils and is run out guided by a groove in the slide, which is pivoted at its outboard end; trucks at its inboard end make it easy to traverse the mounting. If the pivot pin was located inside the gunport – called the ‘inside principle’ – the port could be smaller, but those over the channels might pose a danger to the shrouds from blast; the alternative ‘outside principle’, with the pivot stepped on the outboard edge of the sill, required a larger port, making the crew more vulnerable when reloading.

Carronades, with their range limitations, were perfect for frigates because they complemented a powerful battery of long-range guns on the deck below, and in many of the single-ship actions of the 1790s between nominally equal opponents, carronades gave the Royal Navy a massive firepower advantage. The French response was both slow and inadequate: the brass 36pdr obusier (howitzer) introduced about 1787 was a poor weapon, and it was not until 1808 that they had a satisfactory iron carronade, and even then of only 24pdr calibre.

The success of the carronade during the Napoleonic Wars led to their widespread usage throughout the British fleet, and smaller vessels often had their complete armament, except a couple of chase guns, replaced by carronades. They were expected to use speed and manoeuvrability to bring their guns to bear, but if disabled aloft they proved very vulnerable to any opponent with longer-ranged armament. A number of such actions during the War of 1812 prompted some reconsideration of their utility, and after 1815 they were gradually superseded by more powerful weapons – generally shortened forms of 32pdr long guns in varying lengths and hence weights. By the late 1820s carronades were no longer included in the established armament of new frigates and the carronade principle was eventually abandoned completely in the 1830s.