Found an official USN website for the USS Constitution and, whilst surfing, found reference to the ship's "orlop deck". Not a word I'd heard before (the stales's being well know for their land-lubbing tendencies) so LIU. Here's the definition.

"The Orlop Deck and Hold were used for storing the necessities of a long voyage - food, fresh water, spare sails, ammunition, clothing, personal effects and alcohol - the latter with a permanent Marine guard! The ship's supply of gunpowder was kept in fore and aft magazines, lined with copper to prevent stray sparks from igniting it. The "powder monkeys " - boy sailors who would pass the charges up through hatches in the ceiling - worked in near darkness, their only light coming from candle lanterns behind thick glass bull's eyes. On this deck too was the Carpenter's walk, a narrow passage to give the ship's carpenter access to any damage below the waterline."

So there you go!

stales