Kilderkin

1882: 23 Hen. VIII, cap. 4... The barrel of beer is to hold 36 gallons, the kilderkin 18 gallons the firkin 9. But the barrel, kilderkin, and firkin of ale are to contain 32, 16, and 8 gallons. — James Edwin Thorold Rogers, A History of Agriculture and Prices in England, Volume 4, p. 205.

Barrels came in firkins, nine gallons; kilderkins, eighteen gallons; halves, twenty-seven gallons; barrels, thirty-six gallons and hogsheads, fifty-four.