The Admiral class was built in response to French ironclad battleships of the and es.
Anson and her
sister ship, , were enlarged and improved versions of the previous pair of Admirals, and . The sisters had a
length between perpendiculars of , a
beam of , and a
draught of at
deep load. They displaced at normal load, some heavier than
Howe and
Rodney and heavier than the first ship of the
class, . The ships had a complement of 525–536 officers and
ratings.
Propulsion Anson was powered by two 3-cylinder inverted
compound-expansion steam engines, each driving one
propeller. The
Humphreys engines produced a total of at normal
draught and with
forced draught, using steam provided by a dozen
cylindrical boilers.
Armament Unlike
Collingwood, the later four Admiral-class ships had a main armament of 30-
calibre rifled breech-loading (BL) Mk II guns, rather than the guns in the earlier ship. The four guns were mounted in two twin-gun, pear-shaped
barbettes, one forward and one aft of the
superstructure. The barbettes were open, without hoods or
gun shields, and the guns were fully exposed. The shells fired by these guns were credited with the ability to penetrate of
wrought iron at using a charge of of
smokeless brown cocoa (SBC). At maximum elevation, the guns had a range of around with SBC; later a charge of of
cordite was substituted for the SBC which extended the range to about . There were significant delays in the production of the heavy guns for this ship and her sisters, due to cracking in the innermost layer of the guns, that significantly delayed the delivery of these ships. The
secondary armament of the Admirals consisted of six 26-calibre
BL Mk IV guns on single mounts positioned on the
upper deck amidships, three on each
broadside. They fired shells that were credited with the ability to penetrate of wrought iron at 1000 yards. For defence against
torpedo boats the ships carried a dozen
QF 6-pounder () Hotchkiss guns and 10
QF 3-pounder () Hotchkiss guns. They also mounted five above-water
torpedo tubes, one in the bow and four on the broadside. The barbettes ranged in thickness from with the main ammunition hoists protected by armoured tubes with walls 12 inches thick. The
conning towers also had walls of that thickness as well as roofs thick. The deck of the central armoured citadel had a thickness of and the lower deck was thick from the ends of the belt to the bow and stern. ==Construction and career==