An officer could command a ship without holding the substantive rank of captain. Jervis first acted in command when a captain was ill, later held command as a commander, and became a post captain when appointed captain of the rated HMS Gosport. The explanation rejects a supposed automatic three-year wait and shows how appointment, ship rating, and publication of the command determined the contemporary usage. It is a useful warning against treating the person commanding a vessel and the officer's formal rank as interchangeable in age-of-sail sources.
Notable Point · 15:43-19:20
What post captain meant in the Georgian Royal Navy
Jervis's temporary commands clarify the difference between commanding a ship, holding captain's rank, and being posted to command a rated vessel.