Converting or designing an ironclad meant accepting less height and fewer guns than a conventional ship of the line could carry. Machinery and armour imposed severe weight penalties, so each remaining gun had to damage ships with comparable protection. The breech-loading 7-inch Armstrong gun and Parrott rifles associated with the American Civil War place naval development within a wider race between armour and penetration. Designers had to assume that an opponent could field equally capable protection. Armour-piercing power became a basic requirement.
Notable Point · 36:19-38:25
Heavy guns for armoured warships
Engines and armour consumed weight high in the ship, so designers carried fewer guns powerful enough to defeat enemy armour.