<P> Once a boy, further advancement could be obtained through various specialties . A cabin boy assisted with the ship's kitchen, as well as other duties, while a powder monkey helped in the ship's armory . One of the highest positions for a boy was that of "officer's servant". This position was usually reserved for "young gentlemen" who joined a ship between the ages of 12 and 15 and was seen as a preparatory to becoming a midshipmen . </P> <P> Prior service as a ship's boy was recorded as sea - service; officers' servants could further credit their sea time towards the mandatory requirement for sea time in order to attempt the Lieutenants' Commission Board . After the Age of Sail ended, the position of ship's boy became an actual Royal Navy rank known as "Boy seaman". </P> <Table> <Tr> <Th> Position </Th> <Th> Status </Th> <Th> Appointing Agency </Th> <Th> Messing & berthing </Th> <Th> Uniform </Th> <Th> Notes </Th> </Tr> <Tr> <Td_colspan="7"> </Td> </Tr> <Tr> <Td> Commodore </Td> <Td> Commissioned officer </Td> <Td> Admiralty </Td> <Td> Great Cabin </Td> <Td> Blue frock coat with gold laced buttons . </Td> <Td> Special grade for captains in charge of multiple vessels </Td> </Tr> <Tr> <Td> Captain </Td> <Td> Vessel commanding officer </Td> </Tr> <Tr> <Td> Commander </Td> <Td> Blue frock coat white waist coat . </Td> <Td> Non-rated ship captain . Full title "master and commander" </Td> </Tr> <Tr> <Td> Lieutenant </Td> <Td> Wardroom </Td> <Td> Division officer / watch officer </Td> </Tr> <Tr> <Td> Acting lieutenant </Td> <Td> Warrant officer </Td> <Td> Ship's captain </Td> <Td> No established uniform--recipients would wear the uniform of the last grade held </Td> <Td> Later known as sub-lieutenant </Td> </Tr> <Tr> <Td> Master </Td> <Td> Navy Board </Td> <Td> Blue frock coat with gold Navy buttons </Td> <Td> Highest ranked warrant officer on board </Td> </Tr> <Tr> <Td> Purser </Td> <Td> Victualling Board </Td> <Td> Ship's accountant, responsible for supplies </Td> </Tr> <Tr> <Td> Surgeon </Td> <Td> Sick and Hurt Board </Td> <Td> Ship's medical officer </Td> </Tr> <Tr> <Td> Chaplain </Td> <Td> Church of England </Td> <Td> Only present on larger vessels </Td> </Tr> <Tr> <Td> Midshipman </Td> <Td> Cockpit officer </Td> <Td> Various methods for appointment </Td> <Td> Cockpit </Td> <Td> Blue frock coat, white button collar patch </Td> <Td> Officer candidate position </Td> </Tr> <Tr> <Td> Midshipman's mate </Td> <Td> Cockpit mate </Td> <Td> Blue frock coat with white trim </Td> <Td> Special grade reserved for master's mates who had passed the examination for lieutenant </Td> </Tr> <Tr> <Td> Master's mate </Td> <Td> Could also be rated as "second master" </Td> </Tr> <Tr> <Td> Surgeon's mate </Td> <Td> Sick and Hurt Board </Td> <Td> Ship's medic on smaller vessels </Td> </Tr> <Tr> <Td> Captain's Clerk </Td> <Td> Civilian </Td> <Td> Typically hired by captain </Td> <Td> Civilian clothing </Td> <Td> Clerical duties on board ship </Td> </Tr> <Tr> <Td> School teacher </Td> <Td> Only present on larger ships . Primary duty to instruct midshipmen in academic matters </Td> </Tr> <Tr> <Td> Steward </Td> <Td> Crew's messing and berthing </Td> <Td> A more senior cook and servant, usually reserved for flagships and larger vessels </Td> </Tr> <Tr> <Td> Cook </Td> <Td> Normally an older retired or injured seaman </Td> </Tr> <Tr> <Td> Gunner </Td> <Td> Standing officer </Td> <Td> Shipboard appointment by captain </Td> <Td> Blue frock coat with Navy buttons </Td> <Td> In charge of all ship's armaments </Td> </Tr> <Tr> <Td> Boatswain </Td> <Td> Most experienced deck seaman aboard </Td> </Tr> <Tr> <Td> Carpenter </Td> <Td> Shipboard issued crew clothing </Td> <Td> Head of the carpenter's team </Td> </Tr> <Tr> <Td> Armourer </Td> <Td> Petty officer </Td> <Td> Senior petty officers </Td> </Tr> <Tr> <Td> Ropemaker </Td> </Tr> <Tr> <Td> Caulker </Td> </Tr> <Tr> <Td> Master - at - arms </Td> </Tr> <Tr> <Td> Sailmaker </Td> <Td> Mid-grade petty officer </Td> </Tr> <Tr> <Td> Yeoman </Td> <Td> Two on board: Yeoman of the sheets & yeoman of the powder room </Td> </Tr> <Tr> <Td> Coxswain </Td> <Td> Deck hand specialist petty officer </Td> </Tr> <Tr> <Td> Quartermaster </Td> <Td> Helmsman on board the ship serving watch at the ship's wheel </Td> </Tr> <Tr> <Td> Cooper </Td> <Td> Worked directly for the ship's purser </Td> </Tr> <Tr> <Td> Ship's corporal </Td> <Td> Assistant to the master - at - arms </Td> </Tr> <Tr> <Td> Watch captains </Td> <Td> Experienced seaman in charge of a watch team </Td> </Tr> <Tr> <Td> Armourer's mate </Td> <Td> Junior petty officer </Td> </Tr> <Tr> <Td> Gunner's mate </Td> </Tr> <Tr> <Td> Boatswain's mate </Td> </Tr> <Tr> <Td> Caulker's mate </Td> </Tr> <Tr> <Td> Carpenter's mate </Td> </Tr> <Tr> <Td> Sailmaker's mate </Td> </Tr> <Tr> <Td> Quartermaster's mate </Td> </Tr> <Tr> <Td> Gunsmith </Td> <Td> Seaman </Td> <Td> Seaman specialists </Td> </Tr> <Tr> <Td> Quarter gunner </Td> </Tr> <Tr> <Td> Carpenter's crew </Td> </Tr> <Tr> <Td> Able seaman </Td> <Td> Seaman with more than three years experience </Td> </Tr> <Tr> <Td> Ordinary seaman </Td> <Td> Seaman with at least one year experience </Td> </Tr> <Tr> <Td> Landsman </Td> <Td> Seaman with less than one year experience </Td> </Tr> <Tr> <Td> Boy </Td> <Td> Servant </Td> <Td> Lowest possible position on board, normally held by boys 12 years or younger . </Td> </Tr> </Table> <Tr> <Th> Position </Th> <Th> Status </Th> <Th> Appointing Agency </Th> <Th> Messing & berthing </Th> <Th> Uniform </Th> <Th> Notes </Th> </Tr>

What are the ranks on a navy ship
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