The rating system began with the 1625-26 pay establishment, which needed to distinguish compensation for officers and crews serving in ships of different importance. It was not initially a taxonomy of tactical value or employment. Repeated association between ship size and assigned work nevertheless made the rates into practical shorthand for naval roles. The thresholds changed substantially: an early fourth rate needed more than 30 guns and about 140 men, whereas an eighteenth-century fourth rate normally mounted 46 to 60 guns and carried a considerably larger complement.
Notable Point · 15:07-17:09
The rating system began as a pay system
The early rating system classified officers' pay before it hardened into a practical shorthand for ship size and employment.