Scale: 1:24. Plan showing a plan and side elevation through the deck for an 18 pounder carronade mounted on the 'inside' principle, for Cerberus (1779), a 32-gun Fifth Rate frigate and Cyclops (1779), 26-gun Sixth Rate. The Alcide (1779), a 74-gun Third Rate, two-decker, was not fitted with the system.

The plan is annotated: 'A copy sent from Woolwich Received 11 September 1779 [,] give the original to Mr Pukey [Puckey, Assistant to Master Shipwright, 1775-1788] to cause them to be fitted on board Cyclops[.] the Alcide sailed this day not fitted here, 13 September 1779.'

This system of mounting carronades was abandoned due to the threat of setting the rigging on fire. The three-step elevation system was also abandoned.

An Admiralty Order for the Enterprize class, of which the Cyclops was one, dated 2 February 1780 ordered the quarterdeck armament to include 4x 18 pdr carronades and the forecastle deck 2x 18 pdr carronades. The Amazon class, of which Cerberus was one, were also fitted with 18 pdr carronades.