The origins of the customary units of measurement in South Asia are varied. As in Europe, there were various local systems of everyday measurements of length, mass and dry volume (the latter being a de facto measure of mass for many staple grains), while gold, pearls and gemstones were weighed on a different, slightly more standardized scale. Several of the more important units were cognate with units of measurement in the Arabian Peninsula to the West or in China to the East, to facilitate trade.
During the period of British India, these South Asian units cohabited with imperial units. Some South Asian customary units were redefined in terms of imperial Units by an Ordinance of 1833, [1] and several gained sufficient currency among the colonial population to be listed in the first edition of the Oxford English Dictionary . An early attempt was made at metrication with the Indian Weights and Measures of Capacity Act, 1871, [2] but this had still not been implemented in practice in 1922. [3] [4]
Full metrication with the passage of the Standards of Weights and Measures Act, 1956, [5] now replaced by the Standards of Weights and Measures Act, 1976: [6] these Acts quote the legal conversion factors for imperial units to SI units. Exact conversions can be made for customary units if they had previously been defined in terms of imperial units: however, even when legally defined, the value of a unit could vary between different localities. [4]
The imperial system of units, imperial system or imperial units is the system of units first defined in the British Weights and Measures Act 1824 and continued to be developed through a series of Weights and Measures Acts and amendments.
Metrication or metrification is the act or process of converting to the metric system of measurement. All over the world, countries have transitioned from local and traditional units of measurement to the metric system. This process began in France during the 1790s, and has persistently advanced over two centuries, accumulating into 95% of the world officially only using the modern metric system. Nonetheless, this also highlights that certain countries and sectors are either still transitioning or have chosen not to fully adopt the metric system.
United States customary units form a system of measurement units commonly used in the United States and most U.S. territories, since being standardized and adopted in 1832. The United States customary system developed from English units that were in use in the British Empire before the U.S. became an independent country. The United Kingdom's system of measures was overhauled in 1824 to create the imperial system, which was officially adopted in 1826, changing the definitions of some of its units. Consequently, while many U.S. units are essentially similar to their imperial counterparts, there are noticeable differences between the systems.
Chinese units of measurement, known in Chinese as the shìzhì, are the traditional units of measurement of the Han Chinese. Although Chinese numerals have been decimal (base-10) since the Shang, several Chinese measures use hexadecimal (base-16). Local applications have varied, but the Chinese dynasties usually proclaimed standard measurements and recorded their predecessor's systems in their histories.
The long ton, also known as the imperial ton or displacement ton, is a measurement unit equal to 2,240 pounds (1,016.047 kg). It is the name for the unit called the "ton" in the avoirdupois system of weights or Imperial system of measurements. It was standardised in the 13th century. It is used in the United Kingdom and several other Commonwealth of Nations countries alongside the mass-based tonne defined in 1799, as well as in the United States for bulk commodities.
A unit of length refers to any arbitrarily chosen and accepted reference standard for measurement of length. The most common units in modern use are the metric units, used in every country globally. In the United States the U.S. customary units are also in use. British Imperial units are still used for some purposes in the United Kingdom and some other countries. The metric system is sub-divided into SI and non-SI units.
The tola also transliterated as tolah or tole, is a traditional Ancient Indian and South Asian unit of mass, now standardised as 180 grains or exactly ⅜ troy ounce. It was the base unit of mass in the British Indian system of weights and measures introduced in 1833, although it had been in use for much longer. It was also used in Aden and Zanzibar: in the latter, one tola was equivalent to 175.90 troy grains.
A system of units of measurement, also known as a system of units or system of measurement, is a collection of units of measurement and rules relating them to each other. Systems of measurement have historically been important, regulated and defined for the purposes of science and commerce. Instances in use include the International System of Units or SI, the British imperial system, and the United States customary system.
The spread of metrication around the world in the last two centuries has been met with both support and opposition.
Traditional Japanese units of measurement or the shakkanhō (尺貫法) is the traditional system of measurement used by the people of the Japanese archipelago. It is largely based on the Chinese system, which spread to Japan and the rest of the Sinosphere in antiquity. It has remained mostly unaltered since the adoption of the measures of the Tang dynasty in 701. Following the 1868 Meiji Restoration, Imperial Japan adopted the metric system and defined the traditional units in metric terms on the basis of a prototype metre and kilogram. The present values of most Korean and Taiwanese units of measurement derive from these values as well.
Metrication, or the conversion to a measurement system based on the International System of Units (SI), occurred in India in stages between 1955 and 1962. The metric system in weights and measures was adopted by the Indian Parliament in December 1956 with the Standards of Weights and Measures Act, which took effect beginning 1 October 1958. The Indian Coinage Act was passed in 1955 by the Government of India to introduce decimal coinage in the country. The new system of coins became legal tender in April 1957, where the rupee consists of 100 paise. For the next five years, both the old and new systems were legal. In April 1962, all other systems were banned. This process of metrication is called "big-bang" route, which is to simultaneously outlaw the use of pre-metric measurement, metricate, reissue all government publications and laws, and change the education systems to metric.
The maund, mun or mann is the anglicized name for a traditional unit of mass used in British India, and also in Afghanistan, Persia, and Arabia: the same unit in the Mughal Empire was sometimes written as mann or mun in English, while the equivalent unit in the Ottoman Empire and Central Asia was called the batman. At different times, and in different South Asian localities, the mass of the maund has varied, from as low as 25 pounds (11 kg) to as high as 160 pounds (72 kg): even greater variation is seen in Persia and Arabia.
A Seer is a traditional unit of mass and volume used in large parts of Asia prior to the middle of the 20th century. It remains in use only in a few countries such as Afghanistan, Iran, and parts of India although in Iran it indicates a smaller unit of weight than the one used in India.
A unit of measurement, or unit of measure, is a definite magnitude of a quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same kind of quantity. Any other quantity of that kind can be expressed as a multiple of the unit of measurement.
Before the introduction of the Metric system, one may divide the history of Indian systems of measurement into three main periods: the pre-Akbar's period, the period of the Akbar system, and the British colonial period.
The candy or candee, also known as the maunee, was a traditional South Asian unit of mass, equal to 20 maunds and roughly equivalent to 500 pounds avoirdupois (227 kilograms). It was most used in southern India, to the south of Akbar's empire, but has been recorded elsewhere in South Asia. In Marathi, the same word was also used for a unit of area of 120 bighas, and it is also recorded as a unit of dry volume.
The following outline is provided as an overview of and topical guide to the metric system:
The imperial and US customary measurement systems are both derived from an earlier English system of measurement which in turn can be traced back to Ancient Roman units of measurement, and Carolingian and Saxon units of measure.
A variety of units of measurement have been used in Afghanistan to measure length, mass and capacity. Those units were similar to Iranian, Arabian and Indian units. In 1924, Afghanistan adopted the metric system.