Ship Cover for the Devastation class turret ships HMS Thunderer (1872) and HMS Devastion (1871). The documentation mainly relates to the evolving design specifications, focusing on weight, stability, watertight arrangements, machinery, equipment, stores/ammunition capacity, coal endurance, weaponry and armour protection. The date range covered by these documents is the preliminary design sessions from February 1869 to December 1903, by which time both ships were in Reserve.