Last (unit)

The last was a large English unit of weight, mass, volume, and number. It referred to standardized amounts of ships' lading and varied by commodity and over time.

The term derives from Old English hlæst, ultimately from a Proto-Germanic root reconstructed as *hlaþ- or *hlað- ("to place"). It is also parallel and probably influenced by the Middle Dutch and Middle Low German last, used in identical senses as a load, cargo, or standardized unit.

The Assize of Weights and Measures, one of the statutes of uncertain date from c. 1300, defined the wool last as 12 sacks' worth, equivalent to 24 weys, 336 London stone, or 4200 merchants' pounds (about 1835 kg). The last subsequently varied with the different values given to the sack of wool.

The flax and feather lasts were 1700 avoirdupois pounds (about 770 kg).

The English Ordnance Board defined the gunpowder last as 24 barrels of 100 avoirdupois pounds each (2,400 lbs. or about 1090 kg).

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