A chaldron (also chauldron or chalder) was an English measure of dry volume, mostly used for coal; the word itself is an obsolete spelling of

cauldron A cauldron (or caldron) is a large cookware and bakeware, pot (kettle) for cooking or boiling over an open fire, with a lid and frequently with an arc-shaped hanger and/or integral handles or feet. There is a rich history of cauldron lore in r ...

. It was used from the 13th century onwards, nominally until 1963, when it was abolished by the

Weights and Measures Act 1963 Weights and Measures Acts are acts of the British Parliament determining the regulation of weights and measures. It also refers to similar royal and parliamentary acts of the Kingdoms of England and Scotland and the medieval Welsh states. ...

, but in practice until the end of 1835, when the

Weights and Measures Act 1835 Weights and Measures Acts are acts of the British Parliament determining the regulation of weights and measures. It also refers to similar royal and parliamentary acts of the Kingdoms of England and Scotland and the medieval Welsh states. ...

specified that thenceforth coal could only be sold by weight.

Coal

The chaldron was used as the measure for coal from the 13th century, measuring by volume being much more practical than weighing low-value, high-bulk commodities like coal. It was not standardized, and there were many different regional chaldrons, the two most important being the

Newcastle Newcastle usually refers to: *Newcastle upon Tyne, a city and metropolitan borough in Tyne and Wear, England, United Kingdom *Newcastle-under-Lyme, a town in Staffordshire, England, United Kingdom *Newcastle, New South Wales, a metropolitan area ...

and London chaldrons. The Newcastle chaldron was used to measure all coal shipped from

Northumberland Northumberland ( ) is a ceremonial counties of England, ceremonial county in North East England, on the Anglo-Scottish border, border with Scotland. It is bordered by the North Sea to the east, Tyne and Wear and County Durham to the south, Cumb ...

and Durham, and the London chaldron became the standard measure for coal in the east and south of England. Many attempts have been made to calculate the weight of a Newcastle chaldron as used in medieval and early modern times. Coal industry historian John Nef has estimated that in 1421 it weighed , and that its weight was gradually increased by coal traders due to the taxes on coal (which were charged per chaldron) until 1678, when its weight was fixed by law at , later increased in 1694 to . A London chaldron, on the other hand, was defined as "36

bushel A bushel (abbreviation: bsh. or bu.) is an Imperial unit, imperial and United States customary units, US customary unit of volume, based upon an earlier measure of dry capacity. The old bushel was used mostly for agriculture, agricultural pr ...

s heaped up, each bushel to contain a Winchester bushel and , and to be in diameter". This approximated a weight in coal of around . The chaldron was the legal limit for horse-drawn coal waggons travelling by road as it was considered that heavier loads would cause too much damage to the roadways. Railways had standard "chauldron waggons" which were about and around high. The value of a chaldron of coal depended on the size of the lumps of coal and also their water content. Unscrupulous merchants would purchase their coal in lumps as large as possible then sell them in smaller sizes. This was abolished by the

, which legislated that from January 1836 coal was only to be sold by weight.

References

;Notes ;Sources {{Imperial units Imperial units Coal

Coal

See also

References