Up funnel, down screw!
This is an exhaustive survey of the development of the 'cruiser' (the category includes warships called variously frigates, corvettes and sloops before the formal term cruiser was adopted late in the period) in the RN, from the paddle sloop Hermes completed in 1835 to the armoured cruiser Defence completed in 1909, including the ships' careers which often extended beyond the end of the Kaiser's War, and finally the first battle cruiser - Invincible - conceived as a logical extrapolation of the armoured cruiser, not a cut-down battleship.
The background was a Cold War with France (including fears following the rise of the tin-pot megalomaniac Napoleon III); a mistrust of possible ambitions of the nascent United States, itself unenchanted by our Civil War support for the Confederacy, to throttle our trade; and latterly a perceived threat from Russia. Innovations such as screw propulsion; fire tube and then water tube boilers, forced draught, high pressure boilers, superheat; oil firing; compound and then triple expansion engines, turbines; feathering screws; ironclad, iron and then steel hulls, armour plate; electricity; breech loading, quick-firers, barbettes, torpedoes and underwater tubes for these; and wireless with its need for aerials crowded upon us. The result was almost no two ships alike, rapid obsolescence and extraordinarily short front-line viability. We were often playing catchup against our potential enemies, even against export ships from British builders (Vickers' export offerings to fourteen different countries are described in an appendix). However the Pax Britannica survived; until 1914 our bluff was not called and only the latest ships described here were ever put to the test of war.
Descriptions of individual ships include informed discussion of their handling qualities under sail and steam. Sail was long necessary to reach far-flung stations until coaling facilities overseas became generally available half way through the period. Sail was also a fallback against the mechanical unreliability and the relatively low thermal, mechanical and propulsive efficiency of steam propulsion in the early years; the need for a sailing rig limited propellers to two blades only, while hoisting arrangements inhibited provision of stern-chasers. Progress down below was reflected in successive change of sailing rig from ship to barque, then barquentine and eventually schooner. In back of this was the problem of accommodating the crew necessary for masts and yards on the one hand and for manning and supplying the armament on the other. Some designs were seriously overcrowded, others perhaps undermanned; habitability in tropical waters was sometimes seriously compromised. While I understand the focus in the book on analysis of Admiralty 'Ship Covers', to comprehend what is going on one sometimes needed more discussion (there is some) of the rising proportion of engine room personnel and stokers.
All warship design is a trade-off between armament, protection, propulsion, endurance, manning and cost. At the top table the last mattered most and decisions were often forced by civilian minds (like Gladstone's) that would not be told the facts of life in respect of professional requirements or even that without imports of food Britain would starve. At Board level there were discussions of strategy and tactics, such as whether we were to prioritise Trade Protection - control of focal points maybe far out in the ocean or close blockade of France (this informed in part, from the middle of the period onwards, by feedback from annual manoeuvres); or to design ships to operate with the main Fleet. War-fighting, defence diplomacy and constabulary roles were in competition. Fleeting aberrations included a torpedo-boat carrier and a ram. There was never enough money, there were never enough ships but somehow we muddled through.
The design story takes us through an (often resisted) increasingly scientific process including, latterly, the use of tank models. We see the Constructors and the Controller and sometimes Armstrongs, ping-ponging one proposal after another as all the time the technical clock moved on (one result must have been a huge amount of discarded design work that still had to be paid for).
Of the 300 pages of text, the first 50 pages are an erudite and very interesting introduction giving the maritime strategic background to the period. The last 18 pages describe the changes wrought by Fisher as 1SL including the repurposing of obsolete ships, some as minelayers. Set abaft the main text and before the eighteen pages of exhaustive details of classes and ships are 35 pages of notes, some half a page long. It's a big book (29 x 25 cm), and to get the best out of it one needs to keep up with these, which is awkward and means managing two bookmarks. Data on any one ship or class is indifferently (and sometimes repetitively) spread between the text, the notes, and the picture captions, but is usefully summarised in an appendix.
The main glory of this beautiful book is the huge selection of photographs, many of which would otherwise have lain unseen in the NMM's encyclopaedic archives, elegantly combined with the text. These are often supported by general arrangement drawings where, however I had difficulty working out what was what.