Tub was a unit of capacity or of weight used in Britain and elsewhere.
British laws for the sale of goods defined a tub of butter as a receptacle of a size which could contain 84 pounds of butter.
[1][2] 1 tub of butter or cheese = 84 pounds[1][2] 1 tub = 1.5 Firkin (1 Firkin = 56 lbs)[1][2] 1 tub = 38 kg The Oxford English Dictionary has quotations illustrating other values of a "tub" as a unit:[3] In Newfoundland, Canada, a tub of coal was defined as 100 pounds, while a tub of herrings was 16 Imperial gallons and a tub of salt was 18 Imperial gallons.
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