Sloop and sloop – what is sloop?

In various places, TFSmith makes it clear he does not know what ship classes mean in the context of the Royal Navy.






First, a quick description of the real definitions.




Battleship
A battleship, line-of-battle-ship, or ship-of-the-line, is a heavily built ship intended to operate in the “line of battle” (i.e. general fleet engagements) though the advent of steam propulsion has made them much more capable of independent action. They have multiple gun decks.
Frigate
A frigate has one gun deck, and carries at least 28 guns (if a screw warship) or a small number of very heavy guns (if a paddle warship). First class frigates could often be combatants rivalling some ships of the line, while second class frigates were less powerful and cheaper. In recognition of their greater power, ironclads or heavily armed ships of less than 28 guns were often referred to as frigates.
Corvette
A comparatively new term in the Royal Navy (introduced in the 1840s) this referred to a small sixth-rate somewhat larger than a sloop. Functionally these are ships with between 20 and 28 guns; in 1862 some smaller ships were classified as corvettes as well, though none went the other way.
Sloop
Smaller warships with a single gun-deck and carrying up to 18 guns, often also three-masted.
Gunvessel
Also known as a “dispatch vessel” in some sources, a gunvessel was a steam-powered craft with between four and six guns.
Gunboat
A gunboat of this time period was also steam powered, and of between two and four guns. The distinction between gunboat and gunvessel reflects size, armament, crew size and role; gunvessels were generally larger than gunboats, faster, and more capable, though of deeper draft.



On several occasions, TFSmith demonstrates that he does not understand these Royal Navy definitions – or, at least, not what ships were actually designated.



Ships described as corvette
The Defence and Resistance are described as ironclad corvettes; their true designation was ironclad frigate, though they were indeed only 22 guns.
The Termagant is described as a corvette, though her true designation was also frigate.
Ships described as sloop
The Rattlesnake and Barrosa are both described as sloops; they are really corvettes (thus demoting them one slot). The same is true of the Charybdis.
Ships described as gunvessel
The term “Gunvessel” is used on only a couple of occasions in the timeline. At one point a small squadron of five Rosario class sloops is described as “five gunvessels” (effectively moving them down one slot on the rating scale). In another section these ships are correctly described as sloops.
Conversely, the British allocation of ships is described as “the squadrons commanded by Milne, Dacres, Smart, and their subordinates included some 24 frigates, 16 corvettes, 24 sloops, and 32 smaller gunvessels”. The category of gunboat is missing entirely (though in an earlier section it was “32 smaller gunboats”) - this suggests TFSmith does not understand the difference between gunboat and gunvessel, using the terms interchangeably.
Ships described as gunboat
The passage here:

The Royal Navy in mid-century was the strongest navy in the world; in some ways, Britain’s fleet was stronger than the rest of the world’s fleets combined – certainly in the number of ocean-going steam line-of-battleships (66, plus more on the stocks), and modern “screw” (or propeller) frigates and corvettes (44 and 26, respectively, plus more under construction) in addition to some 120 smaller steam sloops and gunboats, including sidewheel paddle steamers, capable of cruising off-shore.

Suggests that TFSmith has attempted to frame his definitions such to avoid talking about the Crimean gunboats entirely – there were 63 sloops on the 1861 navy list, and there were c.150 Crimean gunboats and gunvessels (making 210+, not 120).
He also describes Coquette and Cormorant as gunboats of four guns each; in fact they were gunvessels.



During the attack on Portland, the same five-Rosario squadron from above is described as “gunboats” without any clarification; as such these ships have been referred to as gunvessels, gunboats and sloops, sometimes with multiple designations in the same chapter. The Swallow is also referred to as a gunboat, though she was laid down as a gunvessel and rerated as a sloop before launch.



Devastation and Hecate are referred to as “paddle-wheel gunboats” - their true rating was sloop.






If there is a common trend in all these errors, it is that the ships affected are consistently described as one or two steps lower on the “scale” than their true position. No ships are uprated.
It is also clear from the case of the Rosario-class ships that there is little internal consistency either. Ships are labelled as gunboat seemingly if the author has forgotten what they are, gunvessel if he remembers the term exists, sloop if the Royal Navy is using US Navy designations today and corvette if they are frigates without very many guns.