I just finished reading John Beeler’s Birth of the Battleship: British Capital Ship Design 1870-1881, which looks at a time where all the accepted norms of the previous three hundred years were all upset overnight.
In 1815, the Royal Navy was the unchallenged Mistress of the Seas: the most powerful navy in the world. France, the greatest threat to England and her trading empire, had just been destroyed as a military and naval power. The United States had survived the war, but had effectively been neutralized on the sea through much hard fighting. No other rival appeared close to challenging England’s primacy.
Fifty years later, the stasis is being broken technologically. Wind power is giving way to steam. Solid shell cannon are starting to give way to both larger and more complex weapons. Iron is starting to supplant oak as the material of choice for shipbuilding. The renowned duel between USS Monitor and CSS Virginia (formerly the USS Merrimac) sets all the major navies of the world busy considering how to protect their existing fleets and merchant vessels against the new threat of the ironclad.
The English government is suddenly faced with the stark reality that their entire fleet has become or is about to become obsolete. Neither Monitor nor Virginia are ocean-going ships, but the message is clear that no wooden vessel has a prayer of survival against the modern steam-powered ironclad. And even the greatest economic power in the world can’t replace an entire fleet overnight.
The Admiralty couldn’t depend on past experience for guidance, as everything they’d done for hundreds of years was now undecided: what kind of ships do you need to build? How will they be armed? How will they be armoured? How will they be propelled? Bureaucracies are, by nature, not well equipped to face challenges like this. The Royal Navy, from the late 1860’s until the late 1880’s struggled with finding the correct answer, or combination of answers, to meet the needs of the day.
I admit that my interest in British Imperial history fades very quickly after 1815 and only starts to pick up again in the 1870’s, and what little I’d retained of the reading I’d done left me with much disdain for the obvious pattern of muddle and stop-gap planning that clearly defined the Royal Navy’s approach to maintaining the fleet during that time period. I was very wrong in my assumptions, but I was far from alone.
To start with, I assumed that the retention of full sailing rig on steam-powered ships proved the raw incompetence of the Admiralty and their ship designers. What I failed to understand was that there were really two different navies operating under the same flag: the home fleet — close to home port with easy access to coal, drydock, and re-supply — and the colonial fleet which had none of those advantages. Merchant vessels of the 1850-1870 era could depend on refuelling at each end of their scheduled journeys (between fully equipped ports), while the Royal Navy could not. The steam engines of that time period were very inefficient and prone to breakdown: lose your engine in the Indian Ocean or the South Atlantic and you were almost certain to be lost. Sail was essential for Royal Navy ships outside home waters.
Iron as armour was a major step forward, but not without costs: it is far heavier than wood and because you needed it to protect the above-the-waterline essentials of the ship, it made it much harder to ensure that the ship would be stable and sufficiently buoyant in heavy seas (see the story of HMS Captain for an example of what could happen otherwise). It’s always been a rule of thumb in military affairs that you can’t protect everything: by trying to protect everything, you spread your forces (or your armour) too thin and you end up being too weak everywhere. This holds true especially for ship’s armour.
At the same time that you need to add armour to protect the ship, you also need to mount heavier, larger guns. Between placing your order with the shipyard for a new ship, the metallurgical wizards may have (and frequently did) come up with bigger, better guns that could defeat the armour on your not-yet-launched ship. Oh, and you now needed to revise the design of the ship to carry the newer, heavier guns, too.
The ship designers were in a race with the gun designers to see who could defeat the latest design by the other group. It’s no wonder that ships could become obsolete between ordering and coming into service: sometimes, they could become obsolete before launch.
The weapons themselves were undergoing change at a relatively unprecedented rate. As late at the mid-1870’s, a good case could be made for muzzle-loading cannon being mounted on warships: until the gas seal of the breech-loader could be made safe, muzzle-loaders had an advantage of not killing their own crews at distressingly high frequency. Once that technological handicap had been overcome, then the argument came down to the best way to mount the weapons: turrets or barbettes.
To the modern eye, the answer is obvious, but to the men responsible for making the decisions, it was far from obvious that the turret was the better answer. Turrets are heavier than barbettes and required clearer fields of fire (few masted-and-rigged ships could also carry turrets), and also generally required the turret to be mounted higher on the superstructure, which made the ship more top-heavy than an equivalent barbette vessel.
The other weapon controversy at the time was what the primary weapons of the battlefleet would be: gun, torpedo, or ram. The argument for the ram was the weakest, although CSS Virginia had done more damage to the Union fleet with her ram than with her guns. The torpedo was still in the transition stage from something that had to be physically pushed against an enemy ship (like a ram with an explosive charge) and the more modern notion of a self-propelled, unmanned weapon. Perhaps the argument was sealed by the accidental sinking of the HMS Victoria less than a decade later (a less-than-charitable interpretation of the event was fictionalized in Kind Hearts and Coronets in 1949).
In some ways it’s remarkable that the hidebound bureaucrats could keep up in the world’s first real arms race . . . and not only keep up, but stay (slightly) ahead. Each new class of battleship had to be equal to or better than the latest French, German, or Italian ships, yet also stay within fairly strict length, breadth, and displacement limits without going (too far) over budget. Oh, and also be capable of adaptation to whatever new naval gun had been introduced in the time between the ships being laid down and being brought into commission.
To the modern eye, even of someone who followed the general trend of naval technology, the Royal Navy of the early 1880’s looks like a random collection of misfit ships. What isn’t apparent is how much worse the picture could have been. Aside from the bombardment of Alexandria, the Royal Navy of Victoria’s reign exercised a policing rather than a strictly military role: they didn’t need to fight too often because they were clearly stronger than any potential adversaries.
Image detail from 
