Possible Clues:

• Barrel made of wood, sort that's not full
• Wooden keg with 9 imperial gallons
• Small cask formerly used for liquids
• Nine-gallon wooden keg
• Small cask for liquids, butter, fish
• Brewing measure of nine gallons
• Brewing measure equal to 9 gallons
• Wooden container made of conifer family
• Much beer less than completely admirable — get upset inside
• Cask for liquids, butter, salt or fish