The British Battleship. Norman Friedman

either increasing the side armour forward (to the height of the main deck) and aft to 4in or raising the top of the 8in side armour (upper belt) to 2ft above the main deck. J was the 13.5in equivalent. It would require a foot more beam on a maximum draught of 31ft and total fuel load would have to be limited to 3000 tons. The ship would lose a quarter-knot of speed compared to St Vincent.

      The Sea Lords now asked for a combination of the two most attractive alternatives, B and I, with all 4in guns removed from turret tops and the additional engine room bulkhead. Controller added that, in view of the improvements being achieved in AP shells, the ship should have better internal protection against bursts. That might mean either a doubled main deck (1½in) or a raised upper (8in) belt. In the latter case, the upper belt might be thinned to 7in up to about 3ft from the upper deck, so that the main deck could be lighted through scuttles.

      Watts returned with Designs K and L. In K the after echelon turret was given a greater training angle abaft than before the beam, as in the Improved Invincible (Indefatigable); in L the reverse was the case. Doubling the main deck would add about 280 tons in K and 300 in L; the altered upper belt would add 330 tons to K and 350 to L. Watts preferred the thicker main deck, which would add less weight but would also add strength (the thicker upper belt would not). Watts had also considered adding 4in armour at the ends (Design I), which would add another 200 tons.

      Controller chose K; on 29 June he asked Watts for a ‘fairly comprehensive comparison’ between it and St Vincent. Blast was apparently much less of a concern than before, presumably thanks to periscopic sights. Watts claimed that both waist turrets could fire right ahead or astern without interference from gun blast (presumably because they were well separated fore and aft), so the ship would have six guns available for end-on fire (assuming ‘X’ turret could not fire over ‘Y’). It might be possible to fire both turrets using periscopic sights, ‘but this has yet to be proved by experiment’. On 7 July Controller wrote Watts that the Sea Lords concurred with him in choosing K.

      Controller attached Watts’ Legend (dated 17 July 1908) for an alternate Design M, which had ten 13.5in guns similarly arranged to those in K. They could be accommodated on the same length as K (520ft, but with 87ft rather than 85ft beam; 21,500 tons rather than 20,350 tons). This somewhat larger ship would require 26,000 IHP equivalent to make the required 21 knots, compared to 25,500 IHP for K and 24,500 IHP for St Vincent.

      Watts submitted a Legend and rough outline drawing for the K Design (Improved St Vincent) on 27 July.²² To meet the wishes of First Lord (presumably to cut costs), length was reduced from 520ft to 510ft. To do that, the ram form of bow used in Dreadnought was readopted (in effect a bulbous bow, for greater hydrodynamic efficiency despite the reduced length), the positions of ‘X’ and ‘Y’ gunhouses were slightly altered and ‘A’ gun house was moved slightly closer to the bow. This design also offered better subdivision (four rather than two engine rooms). The turret-top 4in guns were eliminated, all twenty guns being in the superstructure or under the forecastle. Watts pointed out that K offered 25 per cent more broadside than St Vincent at only 2.25 per cent more cost.

      The Bellerophon class traded a thinner waterline belt and protective deck for a complete torpedo bulkhead, this choice reflecting the considerable weight then accorded to the underwater threat. Neptune added a protective upper deck atop the belt and splinter protection inboard. In theory the upper armour deck should have burst AP shells arriving at shallow angles, coming over the belt. (John Roberts)

      HMS Australia and New Zealand were near-repeats of Indefatigable, but with enlarged bridges (note that the compass platform curves and comes well forward of the charthouse). Like the other 1909–10 ships, they had only a single control top, but in their case the mainmast was retained to handle boats. New Zealand is shown as completed. Australia could initially (but not later) be distinguished by the rudimentary platform atop her mainmast. (Alan C Green via State Library of Victoria and [view from aft] Dr David Stevens, RAN Seapower Centre)

      Eliminating the new transverse engine-room bulkhead (reverting to the earlier machinery arrangement) would save 260 tons and £25,000. Watts pointed out that eliminating the bulkhead would leave the ship no better or worse off than seven dreadnoughts currently under construction. However, a handwritten note by Controller (Jackson), on the Legend in the Admiralty file argues otherwise: ‘I consider the additional bulkhead in the Engine Room one of the principal improvements in the general design of Dreadnought type, its absence in the vessels of that type now under construction being, in my opinion, rather a weak spot in that design. I have looked for an opportunity of introducing it and consider it well worth the extra cost involved.’ Jackson later added that further consideration of turbine arrangement might make it possible to add the bulkhead on the same displacement. Even without the bulkhead, he considered K a great advance over St Vincent at a relatively small increase in displacement and cost. This version was designated K2.²³

      Given the tight schedule, the sketch design had to be approved immediately. It was already late in the year to produce building drawings. Tenders for machinery had to be called for in September 1908, so it was proposed that this step should be taken immediately even though formal Board approval of the drawings had not been given. Since the ship had already been approved, she should be laid down before the end of the Financial Year (by the end of February 1909, from a later Minute). The sketch design was approved on the understanding that displacement at Legend draught should not exceed 20,000 tons (when Controller approved the design on 1 August 1908, he limited displacement to 19,750 tons, even though Watts pointed out that further cuts in displacement would require undesirable reduction in protection. This battleship was HMS Neptune.

      Photographed shortly before Jutland, Indefatigable shows early wartime changes, principally cut-down topmasts and casemate protection for the 4in guns in the after superstructure. Note also the anti-aircraft gun atop the after superstructure. The other two ships had their after superstructures cut away around the mainmast at this time. By this time she had a director bracketed to her foremast under her foretop, but it is not visible here.