Ship Cover for the torpedo ram HMS Polyphemus (1881). The documentation deals extensively with the issues that led to the design of this ship, particularly in the documented opinions of Nathaniel Barnaby and Admiral Boys. Beyond the initial design documentation, the papers also covers the early design layout proposals, statements of dimensions and weights, frequent updates on the design process, stability calculations, arrangement and details of the torpedo battery, cost estimates, machinery output requirements, allocated space for crew and ammunition, crew complement, details of the framing, bottom plating and forepart about the ram/forward torpedo tube, pumping arrangements and details of the armour plate to be employed. Additional papers of interest include printed reports on the issues experienced with the boilers in September 1882 and their resolution by May 1883, and detailed steam trial diagrams from June 1896. In terms of date range, the earliest documents commence in January 1876 at the outset of the design process and conclude in July 1902 with the notofication that the ship is to be put up for sale.