A conventional cruiser must shield ammunition from machinery heat in more than one part of the hull. Grouping the magazines forward can reduce that duplicated protection and turn the saved volume and weight into armour or other capability. The proposed machinery arrangement divides the boiler and engine rooms and links them with steam cross-connections, so efficiency does not require placing the entire propulsion plant in one vulnerable compartment. A protected central steam trunk could preserve flexibility by allowing multiple boiler rooms to supply multiple engines after damage.
Chapter · 49:58-53:34
How concentrated magazines free weight for armour
Concentrating the main armament forward reduces the number of magazine-machinery boundaries and permits a more efficient protected machinery arrangement.