Furious's 18-inch guns and competing Agincourt hypotheses

Furious's single 18-inch mounting is a poor basis for judging what the weapon could do in a larger ship. One hypothesis holds that the gun was shortened to suit Furious and had originally been intended for another design. References to a '15-inch special,' compared with the earlier use of '13.5-inch special' for the 15-inch gun, provide a lead for investigating the unbuilt Agincourt design. Clarke favors six 18-inch guns for that ship, while Drachinifel favors nine or twelve 15-inch guns. These remain competing reconstructions. A six-gun Agincourt at Jutland is then considered as a counterfactual, with the expected effect of its heavy shells kept separate from the unresolved design question.