English units

This article is about the historical development of measurement in England up to 1826. For the non-metric measurement system used in the UK, see Imperial units. For the system currently used in the US with similar unit names, see United States customary units. For an overview of both UK and US non-metric units, see Imperial and US customary measurement systems.

English units were the units of measurement used in England up to 1826 (when they were replaced by Imperial units), which evolved as a combination of the Anglo-Saxon and Roman systems of units. Various standards have applied to English units at different times, in different places, and for different applications.

Use of the term "English units" can be ambiguous, as, in addition to the meaning used in this article, it is sometimes used to refer to the units of the descendant Imperial system as well to those of the descendant system of United States customary units.[1]

The two main sets of English units were the Winchester Units, used from 1495 to 1587, as affirmed by King Henry VII, and the Exchequer Standards, in use from 1588 to 1825, as defined by Queen Elizabeth I.[2][3]

In England (and the British Empire), English units were replaced by Imperial units in 1824 (effective as of 1 January 1826) by a Weights and Measures Act, which retained many though not all of the unit names and redefined (standardised) many of the definitions. In the US, being independent from the British Empire decades before the 1824 reforms, English units were standardized and adopted (as "US Customary Units") in 1832.[4]

  1. ^ Eugene A. Avallone; Theodore Baumeister; Ali Sadegh; Lionel S. Marks (2006). Marks' Standard Handbook for Mechanical Engineers (11 ed.). McGraw Hill. ISBN 978-0-07-142867-5.
  2. ^ "British Imperial System". Encyclopædia Britannica. Encyclopædia Britannica. Retrieved 12 September 2016.
  3. ^ Hosch, William L. (2011). The Britannica Guide to Numbers and Measurement. New York, NY: The Rosen Publishing Group (Britannica Educational Publishing). p. 241. ISBN 978-1-61530-108-9. Retrieved 12 September 2016.
  4. ^ Barbrow, L.E. and Judson, L. V. (1976) Weights and Measures of the United States. National Bureau of Standards Special Publication 447. p. 5–6