Possible Clues:

• Fellow crew member - he maps it at sea
• Sailor on board, a real pal
• One such may be the first to be with you on board
• Fellow sailor provided the maps I fold
• Fellow on board
• Sailor pal
• Fellow sailor finds the map is wrong
• Starbuck, to Ishmael
• Fellow member of a sailing crew
• Fellow on board has time possibly to seize power