Algeria the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. The capital and most populous city is Algiers, located in the far north of the country on the Mediterranean coast. With an area of 2,381,741 square kilometres, Algeria is the tenth-largest country in the world, the world's largest Arab country, the largest in Africa. Algeria is bordered to the northeast by Tunisia, to the east by Libya, to the west by Morocco, to the southwest by the Western Saharan territory and Mali, to the southeast by Niger, to the north by the Mediterranean Sea; the country is a semi-presidential republic consisting of 1,541 communes. It has the highest human development index of all non-island African countries. Ancient Algeria has known many empires and dynasties, including ancient Numidians, Carthaginians, Vandals, Umayyads, Idrisid, Rustamid, Zirid, Almoravids, Spaniards and the French colonial empire. Berbers are the indigenous inhabitants of Algeria. Algeria is a middle power.
It supplies large amounts of natural gas to Europe, energy exports are the backbone of the economy. According to OPEC Algeria has the 16th largest oil reserves in the world and the second largest in Africa, while it has the 9th largest reserves of natural gas. Sonatrach, the national oil company, is the largest company in Africa. Algeria has one of the largest defence budget on the continent. Algeria is a member of the African Union, the Arab League, OPEC, the United Nations and is a founding member of the Arab Maghreb Union. On 2 April 2019, president Abdelaziz Bouteflika resigned after nearly 20 years in power, following pressure from the country’s army after mass protests against Bouteflika's campaign for a fifth term; the country's name derives from the city of Algiers. The city's name in turn derives from the Arabic al-Jazā'ir, a truncated form of the older Jazā'ir Banī Mazghanna, employed by medieval geographers such as al-Idrisi. In the region of Ain Hanech, early remnants of hominid occupation in North Africa were found.
Neanderthal tool makers produced hand axes in the Levalloisian and Mousterian styles similar to those in the Levant. Algeria was the site of the highest state of development of Middle Paleolithic Flake tool techniques. Tools of this era, starting about 30,000 BC, are called Aterian; the earliest blade industries in North Africa are called Iberomaurusian. This industry appears to have spread throughout the coastal regions of the Maghreb between 15,000 and 10,000 BC. Neolithic civilization developed in the Saharan and Mediterranean Maghreb as early as 11,000 BC or as late as between 6000 and 2000 BC; this life, richly depicted in the Tassili n'Ajjer paintings, predominated in Algeria until the classical period. The mixture of peoples of North Africa coalesced into a distinct native population that came to be called Berbers, who are the indigenous peoples of northern Africa. From their principal center of power at Carthage, the Carthaginians expanded and established small settlements along the North African coast.
These settlements served as market towns as well as anchorages. As Carthaginian power grew, its impact on the indigenous population increased dramatically. Berber civilization was at a stage in which agriculture, manufacturing and political organization supported several states. Trade links between Carthage and the Berbers in the interior grew, but territorial expansion resulted in the enslavement or military recruitment of some Berbers and in the extraction of tribute from others. By the early 4th century BC, Berbers formed the single largest element of the Carthaginian army. In the Revolt of the Mercenaries, Berber soldiers rebelled from 241 to 238 BC after being unpaid following the defeat of Carthage in the First Punic War, they succeeded in obtaining control of much of Carthage's North African territory, they minted coins bearing the name Libyan, used in Greek to describe natives of North Africa. The Carthaginian state declined because of successive defeats by the Romans in the Punic Wars.
In 146 BC the city of Carthage was destroyed. As Carthaginian power waned, the influence of Berber leaders in the hinterland grew. By the 2nd century BC, several large but loosely administered Berber kingdoms had emerged. Two of them were established behind the coastal areas controlled by Carthage. West of Numidia lay Mauretania, which extended across the Moulouya River in modern-day Morocco to the Atlantic Ocean; the high point of Berber civilization, unequaled until the coming of the Almohads and Almoravids more than a millennium was reached during the reign of Masinissa in the 2nd century BC. After Masinissa's death in 148 BC, the Berber kingdoms were reunited several times. Masinissa's line survived until 24 AD, when the remaining Berber territory was annexed to the Roman Empire. For several centuries Algeria was ruled by the Romans. Like the rest of No
Mass is both a property of a physical body and a measure of its resistance to acceleration when a net force is applied. The object's mass determines the strength of its gravitational attraction to other bodies; the basic SI unit of mass is the kilogram. In physics, mass is not the same as weight though mass is determined by measuring the object's weight using a spring scale, rather than balance scale comparing it directly with known masses. An object on the Moon would weigh less than it does on Earth because of the lower gravity, but it would still have the same mass; this is because weight is a force, while mass is the property that determines the strength of this force. There are several distinct phenomena. Although some theorists have speculated that some of these phenomena could be independent of each other, current experiments have found no difference in results regardless of how it is measured: Inertial mass measures an object's resistance to being accelerated by a force. Active gravitational mass measures the gravitational force exerted by an object.
Passive gravitational mass measures the gravitational force exerted on an object in a known gravitational field. The mass of an object determines its acceleration in the presence of an applied force; the inertia and the inertial mass describe the same properties of physical bodies at the qualitative and quantitative level by other words, the mass quantitatively describes the inertia. According to Newton's second law of motion, if a body of fixed mass m is subjected to a single force F, its acceleration a is given by F/m. A body's mass determines the degree to which it generates or is affected by a gravitational field. If a first body of mass mA is placed at a distance r from a second body of mass mB, each body is subject to an attractive force Fg = GmAmB/r2, where G = 6.67×10−11 N kg−2 m2 is the "universal gravitational constant". This is sometimes referred to as gravitational mass. Repeated experiments since the 17th century have demonstrated that inertial and gravitational mass are identical.
The standard International System of Units unit of mass is the kilogram. The kilogram is 1000 grams, first defined in 1795 as one cubic decimeter of water at the melting point of ice. However, because precise measurement of a decimeter of water at the proper temperature and pressure was difficult, in 1889 the kilogram was redefined as the mass of the international prototype kilogram of cast iron, thus became independent of the meter and the properties of water. However, the mass of the international prototype and its identical national copies have been found to be drifting over time, it is expected that the re-definition of the kilogram and several other units will occur on May 20, 2019, following a final vote by the CGPM in November 2018. The new definition will use only invariant quantities of nature: the speed of light, the caesium hyperfine frequency, the Planck constant. Other units are accepted for use in SI: the tonne is equal to 1000 kg. the electronvolt is a unit of energy, but because of the mass–energy equivalence it can be converted to a unit of mass, is used like one.
In this context, the mass has units of eV/c2. The electronvolt and its multiples, such as the MeV, are used in particle physics; the atomic mass unit is 1/12 of the mass of a carbon-12 atom 1.66×10−27 kg. The atomic mass unit is convenient for expressing the masses of molecules. Outside the SI system, other units of mass include: the slug is an Imperial unit of mass; the pound is a unit of both mass and force, used in the United States. In scientific contexts where pound and pound need to be distinguished, SI units are used instead; the Planck mass is the maximum mass of point particles. It is used in particle physics; the solar mass is defined as the mass of the Sun. It is used in astronomy to compare large masses such as stars or galaxies; the mass of a small particle may be identified by its inverse Compton wavelength. The mass of a large star or black hole may be identified with its Schwarzschild radius. In physical science, one may distinguish conceptually between at least seven different aspects of mass, or seven physical notions that involve the concept of mass.
Every experiment to date has shown these seven values to be proportional, in some cases equal, this proportionality gives rise to the abstract concept of mass. There are a number of ways mass can be measured or operationally defined: Inertial mass is a measure of an object's resistance to acceleration when a force is applied, it is determined by applying a force to an object and measuring the acceleration that results from that force. An object with small inertial mass will accelerate more than an object with large inertial mass when acted upon by the same force. One says. Active gravitational mass is a measure of the strength of an object's gravitational flux. Gravitational field can be measured by allowing a small "test object" to fall and measuring its free-fall acceleration. For example, an object in free fall near the Moon is subject to a smaller gravitational field, hence
An oil is any nonpolar chemical substance, a viscous liquid at ambient temperatures and is both hydrophobic and lipophilic. Oils have a high carbon and hydrogen content and are flammable and surface active; the general definition of oil includes classes of chemical compounds that may be otherwise unrelated in structure and uses. Oils may be animal, vegetable, or petrochemical in origin, may be volatile or non-volatile, they are used for food, medical purposes and the manufacture of many types of paints and other materials. Specially prepared oils are used in some religious rituals as purifying agents. First attested in English 1176, the word oil comes from Old French oile, from Latin oleum, which in turn comes from the Greek ἔλαιον, "olive oil, oil" and that from ἐλαία, "olive tree", "olive fruit"; the earliest attested forms of the word are the Mycenaean Greek, e-ra-wo and, e-rai-wo, written in the Linear B syllabic script. Organic oils are produced in remarkable diversity by plants and other organisms through natural metabolic processes.
Lipid is the scientific term for the fatty acids and similar chemicals found in the oils produced by living things, while oil refers to an overall mixture of chemicals. Organic oils may contain chemicals other than lipids, including proteins and alkaloids. Lipids can be classified by the way that they are made by an organism, their chemical structure and their limited solubility in water compared to oils, they have a high carbon and hydrogen content and are lacking in oxygen compared to other organic compounds and minerals. Crude oil, or petroleum, its refined components, collectively termed petrochemicals, are crucial resources in the modern economy. Crude oil originates from ancient fossilized organic materials, such as zooplankton and algae, which geochemical processes convert into oil; the name "mineral oil" is a misnomer, in that minerals are not the source of the oil—ancient plants and animals are. Mineral oil is organic. However, it is classified as "mineral oil" instead of as "organic oil" because its organic origin is remote, because it is obtained in the vicinity of rocks, underground traps, sands.
Mineral oil refers to several specific distillates of crude oil. Several edible vegetable and animal oils, fats, are used for various purposes in cooking and food preparation. In particular, many foods are fried in oil much hotter than boiling water. Oils are used for flavoring and for modifying the texture of foods. Cooking oils are derived either from animal fat, as butter and other types, or plant oils from the olive, maize and many other species. Oils are applied to hair to give it a lustrous look, to prevent tangles and roughness and to stabilize the hair to promote growth. See hair conditioner. Oil has been used throughout history as a religious medium, it is considered a spiritually purifying agent and is used for anointing purposes. As a particular example, holy anointing oil has been an important ritual liquid for Judaism and Christianity. Color pigments are suspended in oil, making it suitable as a supporting medium for paints; the oldest known extant oil paintings date from 650 AD. Oils are used for instance in electric transformers.
Heat transfer oils are used both as coolants, for heating and in other applications of heat transfer. Given that they are non-polar, oils do not adhere to other substances; this makes them useful as lubricants for various engineering purposes. Mineral oils are more used as machine lubricants than biological oils are. Whale oil is preferred for lubricating clocks, because it does not evaporate, leaving dust, although its use was banned in the USA in 1980, it is a long-running myth that spermaceti from whales has still been used in NASA projects such as the Hubble Telescope and the Voyager probe because of its low freezing temperature. Spermaceti is not an oil, but a mixture of wax esters, there is no evidence that NASA has used whale oil; some oils burn in liquid or aerosol form, generating light, heat which can be used directly or converted into other forms of energy such as electricity or mechanical work. To obtain many fuel oils, crude oil is pumped from the ground and is shipped via oil tanker or a pipeline to an oil refinery.
There, it is converted from crude oil to diesel fuel, fuel oils, jet fuel, kerosene and liquefied petroleum gas. A 42-US-gallon barrel of crude oil produces 10 US gallons of diesel, 4 US gallons of jet fuel, 19 US gallons of gasoline, 7 US gallons of other products, 3 US gallons split between heavy fuel oil and liquified petroleum gases, 2 US gallons of heating oil; the total production of a barrel of crude into various products results in an increase to 45 US gallons. Not all oils used as fuels are mineral oils, see biodiesel and vegetable oil fuel. In the 18th and 19th cent
Dutch units of measurement
The Dutch units of measurement used today are those of the metric system. Before the 19th century, a wide variety of different weights and measures were used by the various Dutch towns and provinces. Despite the country's small size, there was a lack of uniformity. During the Dutch Golden Age, these weights and measures accompanied the Dutch to the farthest corners of their colonial empire, including South Africa, New Amsterdam and the Dutch East Indies. Units of weight included the pond and last. There was an apothecaries' system of weights; the mijl and roede were measurements of distance. Smaller distances were measured in units based on parts of the body – the el, the voet, the palm and the duim. Area was measured by the morgen, hont and voet. Units of volume included the okshoofd, anker and mingel. At the start of the 19th century the Dutch adopted a unified metric system, but it was based on a modified version of the metric system, different from the system used today. In 1869, this was realigned with the international metric system.
These old units of measurement have disappeared, but they remain a colourful legacy of the Netherlands' maritime and commercial importance and survive today in a number of Dutch sayings and expressions. When Charlemagne was crowned Holy Roman Emperor in 800 AD, his empire included most of modern-day Western Europe including the Netherlands and Belgium. Charlemagne introduced a standard system of measurement across his domains using names such as "pound" and "foot". At the Treaty of Verdun, the empire was divided between Charlemagne's three grandsons and Lothair received the central portion, stretching from the Netherlands in the north to Burgundy and Provence in the south. Further fragmentation followed and with it various parts of the empire modified the units of measures in a manner that suited the local lord. By the start of the religious wars, the territories that made up the Netherlands, still part of the Holy Roman Empire, had passed into the lordship of the King of Spain; each territory had its own variant of the original Carolignian units of measure.
Under the Treaty of Westphalia in 1648, the seven Protestant territories that owed a nominal allegiance to the Prince of Orange ceded from the Holy Roman Empire and established their own confederacy but each kept its own system of measures. Pond pond -- 494.09 g. A pond was about the same size as a modern pound, it was around 480 grams, but there was much variation from region to region. The most used measure of weight was the Amsterdam pound.one Amsterdam pound was 494.09 grams, one Gorinchem pound was 466 grams, one Utrecht heavy pound was 497.8 grams. After the metric system was introduced in 1816, the word pond continued to be used, but for 1 kilogram; this doubling in size of the pond in one fell. The name "kilogram" was adopted in 1869, but the pond was only eliminated as a formal unit of measurement in 1937. Pond is still used today in everyday parlance to refer to 500 g, not far from its historical weight; the word pond is used when referring to the pound used in English-speaking countries.
Ons ons, once -- 1/16 pond = 30.881 g. An ons was around 30 grams, but there was much variation; the figures provided above for the weight of the various pounds used in the Netherlands can be divided by 16 to obtain the weights of the various ounces in use. After the metric system was introduced, the word ons continued to be for 100 g; the ons was eliminated as a formal unit of measurement in 1937, but it is still used today in everyday parlance to refer to 100 g. In the Netherlands today the word ons does not refer to its historical weight of around 30 g, but to 100 g. Last or Scheepslast scheepslast – 4,000 Amsterdam pond = 1,976.4 kg Meaning a "load", a last was the equivalent of 120 cubic feet of shipping space. A last in the Dutch East India Company in the 17th century was about the same as 1,250 kg, becoming as much as 2,000 kg. In the Dutch fishery, a last was a measurement of the fish loaded into the various types of fishing boat in use; the last of these could take 35 to 40 last of the exact amount depending on the location.
In the South Holland fishing villages of Scheveningen and Katwijk, it amounted to 17 crans of herring. A cran held about 900 to 1,000 herring. In Flanders a last was about 1,000 kg of herring; the term fell out of use. Apothecaries' system In the Netherlands there was an apothecaries' system of weights. Mijl mijl = about 5 km The Hollandse mijl was "an hour's walk" which makes it equivalent to the English league – about three English miles or five kilometres, though the exact distance varied from region to region. Other equivalents of the various miles in use were the French lieu marine, 20,000 Amsterdam feet or 20,000 Rijnland feet. Between the introduction of the "Dutch metric system" in 1816 and the reforms in 1869, the word "mijl" was used to refer to a kilometre; the word mijl has since fallen into disuse except when referring to the "mile" used in English-speaking countries. Roede The roede was somewhat smaller than the English rod, 16.5 feet
The metre or meter is the base unit of length in the International System of Units. The SI unit symbol is m; the metre is defined as the length of the path travelled by light in vacuum in 1/299 792 458 of a second. The metre was defined in 1793 as one ten-millionth of the distance from the equator to the North Pole – as a result the Earth's circumference is 40,000 km today. In 1799, it was redefined in terms of a prototype metre bar. In 1960, the metre was redefined in terms of a certain number of wavelengths of a certain emission line of krypton-86. In 1983, the current definition was adopted; the imperial inch is defined as 0.0254 metres. One metre is about 3 3⁄8 inches longer than a yard, i.e. about 39 3⁄8 inches. Metre is the standard spelling of the metric unit for length in nearly all English-speaking nations except the United States and the Philippines, which use meter. Other Germanic languages, such as German and the Scandinavian languages spell the word meter. Measuring devices are spelled "-meter" in all variants of English.
The suffix "-meter" has the same Greek origin as the unit of length. The etymological roots of metre can be traced to the Greek verb μετρέω and noun μέτρον, which were used for physical measurement, for poetic metre and by extension for moderation or avoiding extremism; this range of uses is found in Latin, French and other languages. The motto ΜΕΤΡΩ ΧΡΩ in the seal of the International Bureau of Weights and Measures, a saying of the Greek statesman and philosopher Pittacus of Mytilene and may be translated as "Use measure!", thus calls for both measurement and moderation. In 1668 the English cleric and philosopher John Wilkins proposed in an essay a decimal-based unit of length, the universal measure or standard based on a pendulum with a two-second period; the use of the seconds pendulum to define length had been suggested to the Royal Society in 1660 by Christopher Wren. Christiaan Huygens had observed that length to be 39.26 English inches. No official action was taken regarding these suggestions.
In 1670 Gabriel Mouton, Bishop of Lyon suggested a universal length standard with decimal multiples and divisions, to be based on a one-minute angle of the Earth's meridian arc or on a pendulum with a two-second period. In 1675, the Italian scientist Tito Livio Burattini, in his work Misura Universale, used the phrase metro cattolico, derived from the Greek μέτρον καθολικόν, to denote the standard unit of length derived from a pendulum; as a result of the French Revolution, the French Academy of Sciences charged a commission with determining a single scale for all measures. On 7 October 1790 that commission advised the adoption of a decimal system, on 19 March 1791 advised the adoption of the term mètre, a basic unit of length, which they defined as equal to one ten-millionth of the distance between the North Pole and the Equator. In 1793, the French National Convention adopted the proposal. In 1791, the French Academy of Sciences selected the meridional definition over the pendular definition because the force of gravity varies over the surface of the Earth, which affects the period of a pendulum.
To establish a universally accepted foundation for the definition of the metre, more accurate measurements of this meridian were needed. The French Academy of Sciences commissioned an expedition led by Jean Baptiste Joseph Delambre and Pierre Méchain, lasting from 1792 to 1799, which attempted to measure the distance between a belfry in Dunkerque and Montjuïc castle in Barcelona to estimate the length of the meridian arc through Dunkerque; this portion of the meridian, assumed to be the same length as the Paris meridian, was to serve as the basis for the length of the half meridian connecting the North Pole with the Equator. The problem with this approach is that the exact shape of the Earth is not a simple mathematical shape, such as a sphere or oblate spheroid, at the level of precision required for defining a standard of length; the irregular and particular shape of the Earth smoothed to sea level is represented by a mathematical model called a geoid, which means "Earth-shaped". Despite these issues, in 1793 France adopted this definition of the metre as its official unit of length based on provisional results from this expedition.
However, it was determined that the first prototype metre bar was short by about 200 micrometres because of miscalculation of the flattening of the Earth, making the prototype about 0.02% shorter than the original proposed definition of the metre. Regardless, this length became the French standard and was progressively adopted by other countries in Europe; the expedition was fictionalised in Le mètre du Monde. Ken Alder wrote factually about the expedition in The Measure of All Things: the seven year odyssey and hidden error that transformed the world. In 1867 at the second general conference of the International Association of Geodesy held in Berlin, the question of an international standard unit of length was discussed in order to combine the measurements made in different countries to determine the size and shape of the Earth; the conference recommended the adoption of the metre and the creation of an internatio
Metrication or metrification is conversion to the metric system of units of measurement. Worldwide, there has been a long process of independent conversions of countries from various local and traditional systems, beginning in France during the 1790s and spreading over the following two centuries, but the metric system has not been adopted in all countries and sectors. Whilst most countries in the world are using the metric system as their official system of weights and measures, some countries have not committed to adopting it, or have adopted it as their official system but have not completed the process of full metrication. Most countries have adopted the metric system over a transitional period where both units are used for a set period of time; some countries such as Guyana, for example, have adopted the metric system, but have had some trouble over time implementing it. Antigua and Barbuda "officially" metric, is moving toward total implementation of the metric system, but slower than expected.
The government had announced that they have plans to convert their country to the metric system by the first quarter of 2015. Other Caribbean countries such as Saint Lucia are metric but are still in the process toward full conversion. In the United Kingdom the metric system is the official system for most regulated trading by weight or measure purposes, but some imperial units remain the primary official unit of measurement; as of 2018 the UK has only metricated. According to the US Central Intelligence Agency's online The World Factbook, the metric system has not been adopted by Myanmar and the US; the United States use US customary units as does Liberia. Myanmar uses the Burmese units of measurement. According to The Observer, Liberia are committed to adopting the metric system in the future; some sources now identify Liberia as metric, the government of Myanmar has stated that the country would metricate with a goal of completion by 2019. Both Myanmar and Liberia are metric countries, trading internationally in metric units.
Sierra Leone switched to selling fuel by the litre in May 2011. The European Union used the Units of Measure Directive to attempt to achieve a common system of weights and measures and to facilitate the European Single Market. Throughout the 1990s, the European Commission helped accelerate the process for member countries to complete their metric conversion processes. Among them is the United Kingdom where laws in some or all contexts mandate or permit many imperial measures, such as miles and yards for road-sign distances, road speed limits in miles per hour, pints of beer, inches for clothes; the United Kingdom secured permanent exemptions for the mile and yard in road markings, for the pint of draught beer sold in pubs. In 2007, the European Commission announced that it was to abandon the requirement for metric-only labelling on packaged goods, to allow dual metric–imperial marking to continue indefinitely; the United States, the United Kingdom, Canada have some active opposition to metrication where updated weights and measures laws would make obsolete historic systems of measurement.
Other countries, like France and Japan, that once had significant popular opposition to metrication now have complete acceptance of metrication. The Roman empire used the pes measure; this was divided into 12 unciae. The libra was another measure that had wide effect on European weight and currency long after Roman times, e.g. lb, £. The measure came to vary over time. Charlemagne was one of several rulers who launched reform programmes of various kinds to standardise units for measure and currency in his empire, but there was no real general breakthrough. In medieval Europe, local laws on weights and measures were set by trade guilds on a city-by-city basis. For example, the ell or elle was a unit of length used in Europe, but its length varied from 40.2 centimetres in one part of Germany to 70 centimetres in The Netherlands and 94.5 centimetres in Edinburgh. A survey of Switzerland in 1838 revealed that the foot had 37 different regional variations, the ell had 68, there were 83 different measures for dry grain, 70 measures for fluids and 63 different measures for "dead weights".
When Isaac Newton wrote Philosophiae Naturalis Principia Mathematica in 1687, he quoted his measurements in Parisian feet so readers could understand the size. Examples of efforts to have local intercity or national standards for measurements include the Scottish law of 1641, the British standard imperial system of 1824, still used in the United Kingdom. At one time Imperial China had standardised units for volume throughout its territory, but by 1936 official investigations uncovered 53 values for the chi varying from 200 millimetres to 1250 millimetres. However, revolutionary France was to produce the definitive International System of Units which has come to be used by most of the world today; the desire for a single international system of measurement came from growing international trade and the need to apply common standards to goods. For a company to buy a product produced in another country, they need to ensure that the product would arrive as described; the medieval ell was abandoned in part.
One primary advantage of the International Sy
The avoirdupois system is a measurement system of weights which uses pounds and ounces as units. It was first used in the 13th century and was updated in 1959. In 1959, by international agreement, the definitions of the pound and ounce became standardized in countries which use the pound as a unit of mass; the International Avoirdupois Pound was created. It is the everyday system of weights used in the United States, it is still used, in varying degrees, in everyday life in the United Kingdom and some other former British colonies, despite their official adoption of the metric system. The avoirdupois weight system's general attributes were developed for the international wool trade in the Late Middle Ages, when trade was in recovery, it was based on a physical standardized pound or "prototype weight" that could be divided into 16 ounces. There were a number of competing measures of mass, the fact that the avoirdupois pound had three numbers as divisors may have been a cause of much of its popularity, so that the system won out over systems with 12 or 10 or 15 subdivisions.
The use of this unofficial system stabilized and evolved, with only slight changes in the reference standard or in the prototype's actual mass. Over time, the desire not to use too many different systems of measurement allowed the establishment of "value relationships", with other commodities metered and sold by weight measurements such as bulk goods and smelted metals. In England, Henry VII authorized its use as a standard, Queen Elizabeth I acted three times to enforce a common standard, thus establishing what became the Imperial system of weights and measures. Late in the 19th century various governments acted to redefine their base standards on a scientific basis and establish ratio-metric equations to SI metric system standards, they did not always pick the same equivalencies, though the pound remained similar. An alternative system of mass, the troy system, is used for precious materials; the modern definition of the avoirdupois pound is 0.45359237 kilograms. The word avoirdupois is from Anglo-Norman French aveir de peis "goods of weight".
This term referred to a class of merchandise: aveir de peis, "goods of weight", things that were sold in bulk and were weighed on large steelyards or balances. Only did the term become identified with a particular system of units used to weigh such merchandise; the warfare-impacted orthography of the day has left many variants of the term, such as haberty-poie and haber de peyse. The rise in use of the measurement system corresponds to the regrowth of trade during the High Middle Ages after the early crusades, when Europe experienced a growth in towns, turned from the chaos of warlordism to long distance trade, began annual fairs and commerce, by land and sea. There are two major hypotheses regarding the origins of the avoirdupois system; the older hypothesis is. A newer hypothesis is; the avoirdupois weight system is thought to have come into use in England circa 1300. It was used for weighing wool. In the early 14th century several other specialized weight systems were used, including the weight system of the Hanseatic League with a 16-ounce pound of 7200 grains and an 8-ounce mark.
However, the main weight system, used for coinage and for everyday use, was based on the 12-ounce tower pound of 5400 grains. From the 14th century until the late 16th century, the systems basis, the avoirdupois pound, the prototype for today's international pound was known as the wool pound or the avoirdupois wool pound; the earliest known version of the avoirdupois weight system had the following units: a pound of 6992 grains, a stone of 14 pounds, a woolsack of 26 stone, an ounce of 1⁄16 pound, the ounce was divided into 16 "parts". The earliest known occurrence of the word "avoirdupois" in England is from a document entitled Tractatus de Ponderibus et Mensuris; this document is listed in early statute books under the heading 31 Edward I dated 2 February 1303. More recent statute books list it among statutes of uncertain date. Scholars nowadays believe that it was written between 1266 and 1303. A royal memorandum, it took on the force of law and was recognized as a statute by King Henry VIII and Queen Elizabeth I.
It was repealed by the Weights and Measures Act 1824. In the Tractatus, the word "avoirdupois" refers not to a weight system, but to a class of goods heavy goods sold by weight, as opposed to goods sold by volume, count, or some other method. Since it is written in Anglo-Norman French, this document is not the first occurrence of the word in the English language. Three major developments occurred during the reign of Edward III. First, a statute known as 14o Edward III. St. 1. Cap. 12 "Bushels and Weights shall be made and sent into every County." & acorde qe deſore en auant vn meſure & vn pois ſoit parmy toute Engleterre & qe le Treſorer face faire certaines eſtandardz de buſſel