Comparison of the imperial and US customary measurement systems
Both the imperial and United States customary systems of measurement derive from earlier English systems used in the Middle Ages, that were the result of a combination of the local Anglo-Saxon units inherited from German tribes and Roman units brought by William the Conqueror after the Norman Conquest of England in 1066. Having this shared heritage, the two systems are quite similar; the US customary system is based on English systems of the 18th century, while the Imperial system was defined in 1824, after American independence. Volume may be measured either with specific volume units; the units of cubic length are the same in the imperial and US customary systems but with the specific units of volume they differ. The US customary system has one set of another set for dry goods; the imperial system has only one set defined independently of and subdivided differently from its US counterparts. By the end of the eighteenth century various systems of volume measurement were in use throughout the British Empire.
Wine was measured with units based on the Queen Anne's gallon of 231 cubic inches. Beer was measured with units based on an ale gallon of 282 cubic inches. Grain was measured with the Winchester measure with a gallon of 268.8 cubic inches. In 1824 these were replaced with a single system based on the imperial gallon. Defined as the volume of 10 pounds of distilled water redefined by the Weights and Measures Act 1985 to be 4.54609 L, the imperial gallon is close in size to the old ale gallon. The Winchester measure was made obsolete in the British Empire but remained in use in the US; the Winchester bushel was replaced with an imperial bushel of 8 imperial gallons. The subdivisions of the bushel were maintained; as with US dry measures the imperial system divides the bushel into 4 pecks, 8 gallons, 32 quarts or 64 pints. Thus all of these imperial measures are about 3% larger than their US dry measure counterparts. Fluid measure is not as straightforward; the American colonists adopted a system based on the 231-cubic-inch wine gallon for all fluid purposes.
This became the US fluid gallon. Both the imperial and US fluid gallon are divided into 8 pints or 32 gills. However, whereas the US gill is divided into 4 US fluid ounces, the imperial gill is divided into 5 imperial fluid ounces. So whilst the imperial gallon, quart and gill are about 20% larger than their US fluid measure counterparts, the fluid ounce is about 4% smaller. Note that one avoirdupois ounce of water has an approximate volume of one imperial fluid ounce at 62 °F; this convenient fluid-ounce-to-avoirdupois-ounce relation does not exist in the US system. One noticeable comparison between the imperial system and the US system is between some Canadian and American beer bottles. Many Canadian brewers package beer in a 12-imperial-fluid-ounce bottles. American brewers package their beer in 12-US-fluid-ounce bottles; this results in the Canadian bottles being labelled as 11.5 fl oz in US units when imported into the United States. Because Canadian beer bottles predate the adoption of the Metric System in that country, they are still sold and labelled in Canada as 341 mL.
Canned beer in Canada is sold and labelled in 355 mL cans, when exported to the US are labelled as 12 fl oz. The international yard is defined as 0.9144 metres. This definition was agreed by the United States, the United Kingdom, South Africa and New Zealand through the international yard and pound agreement of 1959; the US survey foot and survey mile have been maintained as separate units for surveying purposes to avoid the accumulation of error that would follow replacing them with the international versions with State Plane Coordinate Systems. The US survey foot is defined so that 1 metre is 39.37 inches, making the international foot of 0.3048 metres two parts per million shorter. This is a little over one eighth of an inch per mile; the main units of length were the same in the US, though the US uses some of the intermediate units, such as the chain and the furlong. At one time the definition of the nautical mile was based on the sphere whose surface is the same as the Clarke Ellipsoid. In the US, the full value of 1853.256 metres was used, but in the Commonwealth, this was rounded to 6080 feet.
These have been replaced by the international version, which rounds the sixtieth part of the 45° to the nearest metre, as 1852 metres. Traditionally, both Britain and the US used three different weight systems: troy weight for precious metals, avoirdupois weight for most other purposes and apothecaries' weight for medicines. However, apothecaries' weight has now been superseded by the metric system. One important difference is the widespread use in Britain of the stone of 14 pounds for body weight; this unit is not used in the United States, although its influence was seen in the practice, until World War II, of selling flour by a barrel of 196 pounds. Another difference arose when Britain abolished the troy pound on January 6, 1879, leaving only the troy ounce and its dec
Obsolete German units of measurement
The obsolete units of measurement of German-speaking countries consist of a variety of units, with varying local standard definitions. Some of these units are still used in everyday speech and in stores and on street markets as shorthand for similar amounts in the metric system. For example, some customers ask for one pound of something; the metric system became compulsory on 1 January 1872, on 1 January 1876, in Austria. Some obsolete German units have names similar to units that were traditionally used in other countries, that are still used in the United Kingdom and the United States. Before the introduction of the metric system in German every town had its own definitions of the units shown below. Towns posted local definitions on a wall of the city hall. For example, the front wall of the old city hall of Rudolstädt has two marks which show the "Rudolstädter Elle", the proper length of the Elle in that city. By 1810 there were 112 different standards for the Elle around Germany. A German geographic mile is defined as 1⁄15 equatorial degrees, equal to 7,420.54 m.
A common German mile, land mile, or post mile was defined in various ways at different places and different times. After the introduction of the metric system in the 19th century, the Landmeile was fixed at 7,500 m, but before there were many local and regional variants: The Rute or Ruthe is of Carolingian origin, was used as a land measure. Many different kinds of Ruthe were used at various times in various parts of the German-speaking world, they were subdivided into differing numbers of local Fuß, were of many different lengths. One source from 1830 lists the following: One hour's travel, used up to the 19th century. In Germany 1⁄2 Meile or 3.71 km. After 1722 in Saxony 1⁄2 post mile = 1000 Dresden rods = 4531 m. In Switzerland 16,000 ft or 4.88 km. 6 feet, after introduction of the metric system 10 feet. Regional variants from 1.75 m in Baden to 3 m in Switzerland. The Lachter was the most common unit of length used in mining in German-speaking areas, its exact length varied from place to place but was between 1.9 and 2.1 metres.
Distance between elbow and fingertip. In the North 2 feet, In Prussia 17⁄8 feet, in the South variable 2 1⁄2 feet; the smallest known German Elle is the longest 811 mm. The Fuß or German foot varied from place to place in the German-speaking world, with time. In some places, more than one type of Fuß was in use. One source from 1830 gives the following values: Usually 1⁄12 foot, but 1⁄11 and 1⁄10. 1⁄12 inch, but 1⁄10. For firewood, 2.905 m3 In general, the Nösel was a measure of liquid volume equal to half a Kanne. Volume varied depending on whether it was beer or wine, its subdivisions were the Viertelnösel. Actual volumes so measured, varied from one state or one city to another. Within Saxony, for example, the "Dresden jar" held 1 US quart or 0.95 litres or 0.83 imperial quarts, so a nösel in Dresden was about 1 US pint. The full volume of a "Leipzig jar" measured 1.2 liters. 1⁄320 Ahm = 1⁄64 Eimer = 1⁄16 Viertel = 1⁄8 Stübchen = 1⁄4 Kannen = 1⁄2 Quartiers = 1 Nösel = 2 Halbnöseln = 4 ViertelnöselnThe nösel was used in minor commerce, as well as in the household to measure meal and such.
These units of measure were valid in Saxony until 1868, when the metric system was introduced. The old measures have continued in private use for decades. One interesting modification was introduced in Thuringia. There, the nösel was, by extension a measure of area, their SI Origins. Springer, Berlin 2003. ISBN 1-85233-682-X Helmut Kahnt, Bernd Knorr: Alte Masse, Münzen und Gewichte.. Bibliographisches Institut Mannheim/Wien/Zürich 1987. Wolfgang Trapp: Kleines Handbuch der Maße, Zahlen Gewichte und der Zeitrechnung. Von. Reclam Stuttgart, 2. Auflage 1996. ISBN 3-15-008737-6 Günther Scholz, Klaus Vogelsang: Kleines Lexikon: Einheiten, Formelzeichen. Fachbuchverlag, Leipzig 1991 ISBN 3-343-00500-2 Johann Christian Nelkenbrechers Taschenbuch eines Banquiers und Kaufmanns: enthaltend eine Erklärung aller ein- und ausländischen Münzen, des Wechsel-Courses, Respect-Tage und anderer zur Handlung gehörigen Dinge. Nachdruck der Ausgabe 1769: VDM Verlag Dr. Müller, Düsseldorf 2004. ISBN 3-936755-58-2 William Tate.
The Modern Cambist: Forming a Manual of Foreign Exchanges, in the Different Operations of Bills of Exchange and Bullion, According to the Practice of All Trading Nations, with Tables of Foreign Weights and Measures, Their Equivalents in English and French. Projekt zur Erschliessung historisch wertvo
International System of Units
The International System of Units is the modern form of the metric system, is the most used system of measurement. It comprises a coherent system of units of measurement built on seven base units, which are the ampere, second, kilogram, mole, a set of twenty prefixes to the unit names and unit symbols that may be used when specifying multiples and fractions of the units; the system specifies names for 22 derived units, such as lumen and watt, for other common physical quantities. The base units are derived from invariant constants of nature, such as the speed of light in vacuum and the triple point of water, which can be observed and measured with great accuracy, one physical artefact; the artefact is the international prototype kilogram, certified in 1889, consisting of a cylinder of platinum-iridium, which nominally has the same mass as one litre of water at the freezing point. Its stability has been a matter of significant concern, culminating in a revision of the definition of the base units in terms of constants of nature, scheduled to be put into effect on 20 May 2019.
Derived units may be defined in terms of other derived units. They are adopted to facilitate measurement of diverse quantities; the SI is intended to be an evolving system. The most recent derived unit, the katal, was defined in 1999; the reliability of the SI depends not only on the precise measurement of standards for the base units in terms of various physical constants of nature, but on precise definition of those constants. The set of underlying constants is modified as more stable constants are found, or may be more measured. For example, in 1983 the metre was redefined as the distance that light propagates in vacuum in a given fraction of a second, thus making the value of the speed of light in terms of the defined units exact; the motivation for the development of the SI was the diversity of units that had sprung up within the centimetre–gram–second systems and the lack of coordination between the various disciplines that used them. The General Conference on Weights and Measures, established by the Metre Convention of 1875, brought together many international organisations to establish the definitions and standards of a new system and standardise the rules for writing and presenting measurements.
The system was published in 1960 as a result of an initiative that began in 1948. It is based on the metre–kilogram–second system of units rather than any variant of the CGS. Since the SI has been adopted by all countries except the United States and Myanmar; the International System of Units consists of a set of base units, derived units, a set of decimal-based multipliers that are used as prefixes. The units, excluding prefixed units, form a coherent system of units, based on a system of quantities in such a way that the equations between the numerical values expressed in coherent units have the same form, including numerical factors, as the corresponding equations between the quantities. For example, 1 N = 1 kg × 1 m/s2 says that one newton is the force required to accelerate a mass of one kilogram at one metre per second squared, as related through the principle of coherence to the equation relating the corresponding quantities: F = m × a. Derived units apply to derived quantities, which may by definition be expressed in terms of base quantities, thus are not independent.
Other useful derived quantities can be specified in terms of the SI base and derived units that have no named units in the SI system, such as acceleration, defined in SI units as m/s2. The SI base units are the building blocks of the system and all the other units are derived from them; when Maxwell first introduced the concept of a coherent system, he identified three quantities that could be used as base units: mass and time. Giorgi identified the need for an electrical base unit, for which the unit of electric current was chosen for SI. Another three base units were added later; the early metric systems defined a unit of weight as a base unit, while the SI defines an analogous unit of mass. In everyday use, these are interchangeable, but in scientific contexts the difference matters. Mass the inertial mass, represents a quantity of matter, it relates the acceleration of a body to the applied force via Newton's law, F = m × a: force equals mass times acceleration. A force of 1 N applied to a mass of 1 kg will accelerate it at 1 m/s2.
This is true whether the object is floating in space or in a gravity field e.g. at the Earth's surface. Weight is the force exerted on a body by a gravitational field, hence its weight depends on the strength of the gravitational field. Weight of a 1 kg mass at the Earth's surface is m × g. Since the acceleration due to gravity is local and varies by location and altitude on the Earth, weight is unsuitable for precision
Imperial and US customary measurement systems
The imperial system of measurement and the US customary system of measurement are both derived from an earlier English system of measurement which in turn can be traced back to Ancient Roman units of measurement, Carolingian and Saxon units of measure. The US Customary system of units was developed and used in the United States after the American Revolution, based on a subset of the English units used in the Thirteen Colonies; the Imperial system of units was developed and used in the United Kingdom and its empire beginning in 1826. US Customary units are the predominant system of units in the United States and the metric system has, to varying degrees, replaced the imperial system in the countries that used it. Most of the units of measure have been adapted in another since the Norman Conquest; the units of linear measure have changed the least – the yard and the chain were measures derived in England. The foot used by craftsman supplanted the longer foot used in agriculture; the agricultural foot was reduced to 10⁄11 of its former size, causing the rod, pole or perch to become 16 1⁄2 agricultural feet.
The furlong and the acre, once it became a measure of the size of a piece of land rather than its value, remained unchanged. In the last thousand years, three principal pounds were used in England; the troy pound was used for precious metals, the apothecaries' pound, was used by pharmacists and the avoirdupois pound was used for general purposes. The apothecaries and troy pounds are divided into 12 ounces while the avoirdupois pound has 16 ounces; the unit of volume, the gallon, has different values in the United States and in the United Kingdom – the US fluid gallon being about 0.83 imperial gallons and the US dry gallon being about 0.97 imperial gallons. Both systems of measure were used in mechanical engineering, though not in electrical engineering; some units of measure such as the horsepower or the British thermal unit have special names but by and large unit names are generated from their constituent components – for example, pounds per square inch. In contrast, the metric system has a special name for pressure—the pascal.
After the United States Declaration of Independence the units of measurement in the United States developed into what is now known as customary units. The United Kingdom overhauled its system of measurement in 1826, when it introduced the imperial system of units; this resulted in the two countries having different gallons. In the century, efforts were made to align the definition of the pound and the yard in the two countries by using copies of the standards adopted by the British Parliament in 1855. However, these standards were of poor quality compared with those produced for the Convention of the Metre. In 1960 the two countries agreed to common definitions of the yard and the pound based on definitions of the metre and the kilogram; this change, which amounted to a few parts per million, had little effect in the United Kingdom, but resulted in the United States having two different systems of linear measure – the international system, the surveyors system. English units of measure, were derived from a combination of Roman and Saxon units of measure.
They were a precursor to both the Imperial system of units and United States customary units which evolved from English Units from 1776 onwards. The earliest records of English units of measure involve the weight of Saxon coins; the penny introduced by Offa was about 20 grains. Edward the Elder increased the weight of the English penny to 26 grains, thereby aligning it with the penny of Charlemagne. By the time of the Norman Conquest, it had decreased to 24 grains; this value was subsequently called the pennyweight and formed the basis of the Troy units of weight—the troy ounce used to this day for weighting precious metals. Edward I broke the link between a coin's value and its weight when he debased the English coinage by introducing a groat which weighed of 89 grains rather than the expected 96 grains; the groat was further devalued in the 1350s. During Saxon times land was measured both in terms of its size; the Domesday Book used an economic unit of measure. In other references the furlong and the rood appear to be units related to ploughing procedures.
Of particular interest was the rood, 15 North German feet in length, the North German foot being equivalent to 335 mm. Craftsmen, on the other hand used a shorter Roman foot. Standardization of weights and measures was a recurring issue for monarchs. In 965 AD, King Edgar decreed "that only one weight and one measure should pass throughout the King's dominion". In 1197 Richard I decreed that the measures of corn and pulse, of wine and ale should be the same throughout all England; the Magna Carta, signed by King John in 1215 extended this to include cloth. Some time between 1266 and 1303 the weights and measures of England were radically revised by a law known as the Composition of Yards and Perches known as the Compositio for short; this law, attributed to either Henry III or his successor Edward I, instituted a new foot, 10⁄11 the length of the old foot, with corresponding reductions in the size of the yard, ell and barleycorn. In 1324 Edward II systematized units of length by defining the inch as 3 barleycorns, the foot as 12 inches, the yard
The ligne or line or Paris line, is a historic unit of length used in France and elsewhere prior to the adoption of the metric system in the late 18th century, used in various sciences after that time. The loi du 19 frimaire an VIII states that one metre is equal to 443.296 French lines. It is vestigially retained today by French and Swiss watchmakers to measure the size of watch movements, in button making, ribbon manufacture. There are 12 lignes to one French inch; the standardized conversion for a ligne is 2.2558291 mm, it is abbreviated with the letter L or represented by the triple prime, ‴. One ligne is the equivalent of 0.0888 international inch. This is comparable in size to the British measurement called "line", used prior to 1824. In the 18th century German button makers began to use the term ligne to measure the diameter of buttons; the consensus definition was. In this sense it measures 1⁄40 of an inch, but not for there were several inches in the kingdoms and petty states of Germany at that time.
Such a measurement became the American measurement called "line", being one-fortieth of the US-customary inch, used measure buttons introduced by German immigrants. It snaps. Ligne is used in measuring the width of ribbons at 11.26 per inch. Line Old French units Horology
The system of imperial units or the imperial system is the system of units first defined in the British Weights and Measures Act of 1824, refined and reduced. The Imperial units replaced the Winchester Standards, which were in effect from 1588 to 1825; the system came into official use across the British Empire. By the late 20th century, most nations of the former empire had adopted the metric system as their main system of measurement, although some imperial units are still used in the United Kingdom and other countries part of the British Empire; the imperial system developed from what were first known as English units, as did the related system of United States customary units. The Weights and Measures Act of 1824 was scheduled to go into effect on 1 May 1825. However, the Weights and Measures Act of 1825 pushed back the date to 1 January 1826; the 1824 Act allowed the continued use of pre-imperial units provided that they were customary known, marked with imperial equivalents. Apothecaries' units are mentioned neither in the act of 1824 nor 1825.
At the time, apothecaries' weights and measures were regulated "in England and Berwick-upon-Tweed" by the London College of Physicians, in Ireland by the Dublin College of Physicians. In Scotland, apothecaries' units were unofficially regulated by the Edinburgh College of Physicians; the three colleges published, at infrequent intervals, the London and Dublin editions having the force of law. Imperial apothecaries' measures, based on the imperial pint of 20 fluid ounces, were introduced by the publication of the London Pharmacopoeia of 1836, the Edinburgh Pharmacopoeia of 1839, the Dublin Pharmacopoeia of 1850; the Medical Act of 1858 transferred to The Crown the right to publish the official pharmacopoeia and to regulate apothecaries' weights and measures. Metric equivalents in this article assume the latest official definition. Before this date, the most precise measurement of the imperial Standard Yard was 0.914398415 metres. In 1824, the various different gallons in use in the British Empire were replaced by the imperial gallon, a unit close in volume to the ale gallon.
It was defined as the volume of 10 pounds of distilled water weighed in air with brass weights with the barometer standing at 30 inches of mercury at a temperature of 62 °F. In 1963, the gallon was redefined as the volume of 10 pounds of distilled water of density 0.998859 g/mL weighed in air of density 0.001217 g/mL against weights of density 8.136 g/mL, which works out to 4.546096 l or 277.4198 cu in. The Weights and Measures Act of 1985 switched to a gallon of 4.54609 L. These measurements were in use from 1826, when the new imperial gallon was defined, but were abolished in the United Kingdom on 1 January 1971. In the US, though no longer recommended, the apothecaries' system is still used in medicine in prescriptions for older medications. In the 19th and 20th centuries, the UK used three different systems for weight. Troy weight, used for precious metals; the distinction between mass and weight is not always drawn. A pound is a unit of mass, although it is referred to as a weight; when a distinction is necessary, the term pound-force may be used to refer to a unit of force rather than mass.
The troy pound was made the primary unit of mass by the 1824 Act. The Weights and Measures Act 1855 made the avoirdupois pound the primary unit of mass. In all the systems, the fundamental unit is the pound, all other units are defined as fractions or multiples of it. Although the 1824 act defined the yard and pound by reference to the prototype standards, it defined the values of certain physical constants, to make provision for re-creation of the standards if they were to be damaged. For the yard, the length of a pendulum beating seconds at the latitude of Greenwich at Mean Sea Level in vacuo was defined as 39.01393 inches. For the pound, the mass of a cubic inch of distilled water at an atmospheric pressure of 30 inches of mercury and a temperature of 62° Fahrenheit was defined as 252.458 grains, with there being 7,000 grains per pound. However, following the destruction of the original prototypes in the 1834 Houses of Parliament fire, it proved impossible to recreate the standards from these definitions, a new Weights and Measures Act was passed in 1855 which permitted the recreation of the prototypes from recognized secondary standards.
The imperial system is one of many systems of English units. Although most of the units are defined in more than one system, some subsidiary units were used to a much greater extent, or for different purposes, in one area rather than the other; the distinctions between these systems are not drawn precisely. One such distinction is that between these systems and older British/English units/systems or newer additions; the term imperial should not be applied to English units that were outlawed in the Weights and Measures Act 1824 or earlier, or which had fallen out of use by that time, nor to post-imperial inventions, such as the slug or poundal. The US customary system is derived from the English units that were in use at the time of settlement; because the United States was independent at the time, these units were unaffected b
Maltese units of measurement
In modern usage, metric is used exclusively in commercial transactions. These units are historical, although they are still used in some limited contexts and in Maltese idioms and set phrases. Many of these terms are directly related to some to Sicilian units; the Weights and Measures Ordinance of 1921 established uniformity in the conversion of such weights and measures. All these measures were defined as simple multiples of the Imperial units in use in Britain. Length units were used for measuring goods and building sizes. Distances were traditionally measured in terms of travel time, which explains the lack of large-scale units. In 1921, these units were redefined with respect to the British Imperial standard; these values reflect this change. These units were all defined in 1921 relative to the British Imperial gallon, defined in the 1824 act; this is equal to 10 pounds of water at a specified air pressure. This is larger than the modern definition. None of the units from this group are mentioned in TY Maltese.
None of these units are mentioned in TY Maltese. Note that there are two conflicting values for the siegħ. All the Maltese mass units were redefined relative to the British Imperial ton in 1921. Before this, the units were based on an Arabic standard. All equivalent measures listed in pounds below are exact values. Nb. There are two distinct units; this system was used during the rule of the Knights of St. John in Malta. Subsequent currencies in use are the Maltese lira. Malta has now switched to using the Euro. Maltese-English Dictionary, appendix p1658, by Aquilina, published by Midsea Books Ltd.. No ISBN available. Teach Yourself Maltese, pp125–6 Att dwar il-Metroloġija Kap. 454