History of measurement
Encyclopedia
Units of measurement were among the earliest tools invented by humans. Primitive societies needed rudimentary measures for numerous tasks such as: constructing dwellings of an appropriate size and shape, fashioning clothing, or bartering food or raw materials.
with the description given by Plutarch
from which a fairly accurate idea of the size of the Attic foot is obtained. In some cases, we have only plausible theories and we must sometimes select the interpretation to be given to the evidence.
By studying the evidence given by all available sources, and by correlating the relevant facts, we obtain some idea of the origin and development of the units. We find that they have changed more or less gradually with the passing of time in a complex manner because of a great variety of modifying influences. We find the units modified and grouped into measurement systems: the Babylonian system, the Egyptian system, the Phileterian system of the Ptolemaic
age, the Olympic system of Greece, the Roman system, and the British system
, to mention only a few.
(3000–1500 BC. Mature period 2600–1900 BC) developed a sophisticated procedure of standardization, using weights and measures, evident by the excavations made at the Indus valley sites. This technical standardization enabled gauging devices to be effectively used in angular measurement and measurement for construction. Calibration
was also found in measuring devices along with multiple subdivisions in case of some devices.
The earliest known uniform systems of weights and measures seem all to have been created at some time in the 4th
and 3rd millennia BC
among the ancient peoples of Egypt
, Mesopotamia
and the Indus Valley, and perhaps also Elam
(in Iran
) as well. The most astounding of these ancient systems was perhaps that of the Indus Valley Civilization
(ca. 2600 BC). The Indus Valley peoples achieved great accuracy in measuring length, mass, and time. Their measurements were extremely precise since their smallest division, which is marked on an ivory scale found in Lothal
, was approximately 1.704 mm (1/16 inch), the smallest division ever recorded on a scale of the Bronze Age
. The decimal
system was thought to be used but in fact, feet and inches are a more accurate indication of the measure used. The measuring devices found in the Indus Valley actually meet the standards used in South Indian architecture and engineering which are feet and inches. In Tamil Nadu, the inch is used in architectural forms per traditional Vaastu Shastras. Traditional architectural forms are built to 1/16 of an inch which is the smallest unit of measure found in the Indus Valley. In addition, the "yard sticks" used in Indus Valley (and in Tamil Nadu) measure exactly 33 inches and are divided into 24 units of 1⅜ inches. The 1⅜ inch is considered to be an angula. A unit of measure 33 inches long is called a hasta, kishku or muzam. A half hasta was also found in the Indus Valley measuring exactly 16½ inches (12 angula at 1⅜ inches). This measure is currently used by traditional architects such as Dr. V. Ganapati Sthapati who comes from an ancient tradition of Shilpis. The discovery of the relationship between Indus Valley measurement (using feet and inches rather than metric measure) and current and traditional Indian architecture per Vaastu Shastras was made by Dr. Jessie J. Mercay, Chancellor of The American University of Mayonic Science and Technology.
Weights were based on units of 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50, 100, 200, and 500, with each unit weighing approximately 28 grams, similar to the English ounce
or Roman uncia, and smaller objects were weighed in similar ratios with the units of 0.871.
Other systems were based on the use of parts of the body and the natural surroundings as measuring instruments. Ancient Indian measurements related to the body are corelated to the finger measure of 1⅜ inch. This measure is found throughout the human body in increments. It is the measure used to build ancient temples and is precisely related to the Indus Valley measuring devices. Early Babylonian and Egyptian
records and the Bible
indicate that length was first measured with the forearm, hand, or finger and that time was measured by the periods of the sun, moon, and other heavenly bodies. When it was necessary to compare the capacities of containers such as gourd
s or clay
or metal vessels, they were filled with plant seeds which were then counted to measure the volume
s. When means for weighing were invented, seeds and stones served as standards. For instance, the carat, still used as a unit for gems, was derived from the carob seed.
, the Indus Valley units of length referred to above and the Mesopotamian cubit were used in the 3rd millennium BC
and are the earliest known units used by ancient peoples to measure length. The measures of length used in ancient India included the dhanus (bow), the krosa (cry, or cow-call) and the yojana
(stage).
The common cubit was the length of the forearm from the elbow to the tip of the middle finger. It was divided into the span of the hand (one-half cubit), the palm or width of the hand (one sixth), and the digit or width of the middle finger (one twenty-fourth) and the span or the length between the tip of little finger to the tip of the thumb. The Sacred Cubit, which was a standard cubit enhanced by an extra span—thus 7 spans or 28 digits long—was used in constructing buildings and monuments and in surveying in ancient Egypt. The inch
, foot, and yard
evolved from these units through a complicated transformation not yet fully understood. Some believe they evolved from cubic measures; others believe they were simple proportions or multiples of the cubit. In whichever case, the Greeks and Romans inherited the foot from the Egyptians. The Roman foot (~296 mm) was divided into both 12 unciae (inches) (~24.7 mm) and 16 digits (~18.5 mm). The Romans also introduced the mille passus (1000 paces) or double steps, the pace being equal to five Roman feet (~1480 mm). The Roman mile
of 5000 feet (1480 m) was introduced into England during the occupation. Queen Elizabeth I
(reigned from 1558 to 1603) changed, by statute, the mile to 5280 feet (~1609 m) or 8 furlongs, a furlong
being 40 rod (unit)
s (~201 m) of 5.5 yards (~5.03 m)each.
The introduction of the yard (0.9144 m) as a unit of length came later, but its origin is not definitely known. Some believe the origin was the double cubit, others believe that it originated from cubic measure. Whatever its origin, the early yard was divided by the binary method into 2, 4, 8, and 16 parts called the half-yard, span, finger, and nail. The association of the yard with the "gird" or circumference of a person's waist or with the distance from the tip of the nose to the end of the thumb of King Henry I
(reigned 1100–1135) are probably standardizing actions, since several yards were in use in Britain.
There were also Rods, Poles and Perches for measurements of length. The following table lists the equivalents.
Length
12 lines = 1 inch
12 inches = 1 foot
3 feet = 1 yard
1760 yards = 1 mile
36 inches = 1 yard
440 yards = quarter mile
880 yards = half mile
100 links = 1 chain
10 chains = 1 furlong
8 furlongs = 1 mile
4 inches = 1 hand
22 yards = 1 chain
5.5 yards = 1 rod, pole or perch
4 poles = 1 chain
40 poles = 1 furlong
, as a unit for measuring print type predates the metric system. Various typographic points were defined, including the Truchet point by Sébastien Truchet (1657–1729), the Fournier point by Pierre Simon Fournier
in 1737 and the Didot point by the Didot brothers, Francois Ambroise and Pierre Francois, in 1755 or 1767 or 1783, which was exactly two Truchet points. The point was first used in the United States in 1878 or 1872 by a Chicago type foundry (Marder, Luse, & Co.
).
The point
was defined as 1/12 of a pica consisting of 1/6 of an inch truncated to thousandths of an inch (1/12 of 0.166 inches) in the USA in 1886 and was quickly adopted by Britain and its colonies;. This number has been approximated in various ways depending on the technology, prejudices, and information available to engineers involved in the production of typesetting machinery since then. Common approximations in use are 1/72.27 inch (now equal to 0.3514598 mm) and simply 1/72 of an inch. Other typographic points
are used in other countries.
The pica in any of several related systems measures 12 points.
, Tower, and troy
systems. The early unit was a grain of wheat or barleycorn used to weigh the precious metals silver and gold. Larger units preserved in stone standards were developed that were used as both units of mass and of monetary currency. The pound
was derived from the mina used by ancient civilizations. A smaller unit was the shekel, and a larger unit was the talent. The magnitude of these units varied from place to place. The Babylonians and Sumerians had a system in which there were 60 shekels in a mina and 60 minas in a talent. The Roman talent consisted of 100 libra (pound) which were smaller in magnitude than the mina. The troy pound (~373.2 g) used in England and the United States for monetary purposes, like the Roman pound, was divided into 12 ounces, but the Roman uncia (ounce) was smaller. The carat is a unit for measuring gemstones that had its origin in the carob seed, which later was standardized at 1/144 ounce and then 0.2 gram.
Goods of commerce were originally traded by number or volume. When weighing of goods began, units of mass based on a volume of grain or water were developed. For example, the talent in some places was approximately equal to the mass of one cubic foot of water. Was this a coincidence or by design? The diverse magnitudes of units having the same name, which still appear today in our dry and liquid measures, could have arisen from the various commodities traded. The larger avoirdupois pound for goods of commerce might have been based on volume of water which has a higher bulk density
than grain. For example, the Egyptian hon was a volume unit about 11 per cent larger than a cubic palm and corresponded to one mina of water. It was almost identical in volume to the present U.S. pint (~473 mL).
The stone, quarter, hundredweight, and ton were larger units of mass used in Britain. Today only the stone continues in customary use for measuring personal body weight. The present stone is 14 pounds (~6.35 kg), but an earlier unit appears to have been 16 pounds (~7.25 kg). The other units were multiples of 2, 8, and 160 times the stone, or 28, 112, and 2240 pounds (~12.7 kg, 50.8 kg, 1016 kg), respectively. The hundredweight was approximately equal to two talents. The ton of 2240 pounds is called the "long ton". The "short ton" is equal to 2000 pounds (~907 kg). A tonne (t) is equal to 1000 kg.
We can trace the division of the circle into 360 degrees and the day into hours, minutes, and seconds to the Babylonians who had sexagesimal system of numbers. The 360 degrees may have been related to a year of 360 days. Many other systems of measurement
divided the day differently; other calendar
s divided the year differently.
was first described 1668, and officially adopted by France in 1799. Over the course of the 1800s and 1900s, it became the dominant system worldwide, with the largest exception being the United States.
Present knowledge
Our present knowledge of early weights and measures comes from many sources. Archaeologists have recovered some rather early standards and preserved them in museums. The comparison of the dimensions of buildings with the descriptions of contemporary writers is another source of information. An interesting example of this is the comparison of the dimensions of the Greek ParthenonParthenon
The Parthenon is a temple on the Athenian Acropolis, Greece, dedicated to the Greek goddess Athena, whom the people of Athens considered their virgin patron. Its construction began in 447 BC when the Athenian Empire was at the height of its power. It was completed in 438 BC, although...
with the description given by Plutarch
Plutarch
Plutarch then named, on his becoming a Roman citizen, Lucius Mestrius Plutarchus , c. 46 – 120 AD, was a Greek historian, biographer, essayist, and Middle Platonist known primarily for his Parallel Lives and Moralia...
from which a fairly accurate idea of the size of the Attic foot is obtained. In some cases, we have only plausible theories and we must sometimes select the interpretation to be given to the evidence.
By studying the evidence given by all available sources, and by correlating the relevant facts, we obtain some idea of the origin and development of the units. We find that they have changed more or less gradually with the passing of time in a complex manner because of a great variety of modifying influences. We find the units modified and grouped into measurement systems: the Babylonian system, the Egyptian system, the Phileterian system of the Ptolemaic
Ptolemaic dynasty
The Ptolemaic dynasty, was a Macedonian Greek royal family which ruled the Ptolemaic Empire in Egypt during the Hellenistic period. Their rule lasted for 275 years, from 305 BC to 30 BC...
age, the Olympic system of Greece, the Roman system, and the British system
English unit
English units are the historical units of measurement used in England up to 1824, which evolved as a combination of the Anglo-Saxon and Roman systems of units...
, to mention only a few.
Earliest known systems
The inhabitants of the Indus Valley CivilizationIndus Valley Civilization
The Indus Valley Civilization was a Bronze Age civilization that was located in the northwestern region of the Indian subcontinent, consisting of what is now mainly modern-day Pakistan and northwest India...
(3000–1500 BC. Mature period 2600–1900 BC) developed a sophisticated procedure of standardization, using weights and measures, evident by the excavations made at the Indus valley sites. This technical standardization enabled gauging devices to be effectively used in angular measurement and measurement for construction. Calibration
Calibration
Calibration is a comparison between measurements – one of known magnitude or correctness made or set with one device and another measurement made in as similar a way as possible with a second device....
was also found in measuring devices along with multiple subdivisions in case of some devices.
The earliest known uniform systems of weights and measures seem all to have been created at some time in the 4th
4th millennium BC
The 4th millennium BC saw major changes in human culture. It marked the beginning of the Bronze Age and of writing.The city states of Sumer and the kingdom of Egypt were established and grew to prominence. Agriculture spread widely across Eurasia...
and 3rd millennia BC
3rd millennium BC
The 3rd millennium BC spans the Early to Middle Bronze Age.It represents a period of time in which imperialism, or the desire to conquer, grew to prominence, in the city states of the Middle East, but also throughout Eurasia, with Indo-European expansion to Anatolia, Europe and Central Asia. The...
among the ancient peoples of Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
, Mesopotamia
Mesopotamia
Mesopotamia is a toponym for the area of the Tigris–Euphrates river system, largely corresponding to modern-day Iraq, northeastern Syria, southeastern Turkey and southwestern Iran.Widely considered to be the cradle of civilization, Bronze Age Mesopotamia included Sumer and the...
and the Indus Valley, and perhaps also Elam
Elam
Elam was an ancient civilization located in what is now southwest Iran. Elam was centered in the far west and the southwest of modern-day Iran, stretching from the lowlands of Khuzestan and Ilam Province, as well as a small part of southern Iraq...
(in Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...
) as well. The most astounding of these ancient systems was perhaps that of the Indus Valley Civilization
Indus Valley Civilization
The Indus Valley Civilization was a Bronze Age civilization that was located in the northwestern region of the Indian subcontinent, consisting of what is now mainly modern-day Pakistan and northwest India...
(ca. 2600 BC). The Indus Valley peoples achieved great accuracy in measuring length, mass, and time. Their measurements were extremely precise since their smallest division, which is marked on an ivory scale found in Lothal
Lothal
Lothal is one of the most prominent cities of the ancient Indus valley civilization. Located in Bhāl region of the modern state of Gujarāt and dating from 2400 BCE. Discovered in 1954, Lothal was excavated from February 13, 1955 to May 19, 1960 by the Archaeological Survey of India...
, was approximately 1.704 mm (1/16 inch), the smallest division ever recorded on a scale of the Bronze Age
Bronze Age
The Bronze Age is a period characterized by the use of copper and its alloy bronze as the chief hard materials in the manufacture of some implements and weapons. Chronologically, it stands between the Stone Age and Iron Age...
. The decimal
Decimal
The decimal numeral system has ten as its base. It is the numerical base most widely used by modern civilizations....
system was thought to be used but in fact, feet and inches are a more accurate indication of the measure used. The measuring devices found in the Indus Valley actually meet the standards used in South Indian architecture and engineering which are feet and inches. In Tamil Nadu, the inch is used in architectural forms per traditional Vaastu Shastras. Traditional architectural forms are built to 1/16 of an inch which is the smallest unit of measure found in the Indus Valley. In addition, the "yard sticks" used in Indus Valley (and in Tamil Nadu) measure exactly 33 inches and are divided into 24 units of 1⅜ inches. The 1⅜ inch is considered to be an angula. A unit of measure 33 inches long is called a hasta, kishku or muzam. A half hasta was also found in the Indus Valley measuring exactly 16½ inches (12 angula at 1⅜ inches). This measure is currently used by traditional architects such as Dr. V. Ganapati Sthapati who comes from an ancient tradition of Shilpis. The discovery of the relationship between Indus Valley measurement (using feet and inches rather than metric measure) and current and traditional Indian architecture per Vaastu Shastras was made by Dr. Jessie J. Mercay, Chancellor of The American University of Mayonic Science and Technology.
Weights were based on units of 0.05, 0.1, 0.2, 0.5, 1, 2, 5, 10, 20, 50, 100, 200, and 500, with each unit weighing approximately 28 grams, similar to the English ounce
English unit
English units are the historical units of measurement used in England up to 1824, which evolved as a combination of the Anglo-Saxon and Roman systems of units...
or Roman uncia, and smaller objects were weighed in similar ratios with the units of 0.871.
Other systems were based on the use of parts of the body and the natural surroundings as measuring instruments. Ancient Indian measurements related to the body are corelated to the finger measure of 1⅜ inch. This measure is found throughout the human body in increments. It is the measure used to build ancient temples and is precisely related to the Indus Valley measuring devices. Early Babylonian and Egyptian
History of Egypt
Egyptian history can be roughly divided into the following periods:*Prehistoric Egypt*Ancient Egypt**Early Dynastic Period of Egypt: 31st to 27th centuries BC**Old Kingdom of Egypt: 27th to 22nd centuries BC...
records and the Bible
Bible
The Bible refers to any one of the collections of the primary religious texts of Judaism and Christianity. There is no common version of the Bible, as the individual books , their contents and their order vary among denominations...
indicate that length was first measured with the forearm, hand, or finger and that time was measured by the periods of the sun, moon, and other heavenly bodies. When it was necessary to compare the capacities of containers such as gourd
Gourd
A gourd is a plant of the family Cucurbitaceae. Gourd is occasionally used to describe crops like cucumbers, squash, luffas, and melons. The term 'gourd' however, can more specifically, refer to the plants of the two Cucurbitaceae genera Lagenaria and Cucurbita or also to their hollow dried out shell...
s or clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
or metal vessels, they were filled with plant seeds which were then counted to measure the volume
Volume
Volume is the quantity of three-dimensional space enclosed by some closed boundary, for example, the space that a substance or shape occupies or contains....
s. When means for weighing were invented, seeds and stones served as standards. For instance, the carat, still used as a unit for gems, was derived from the carob seed.
Units of length
The Egyptian cubitCubit
The cubit is a traditional unit of length, based on the length of the forearm. Cubits of various lengths were employed in many parts of the world in Antiquity, in the Middle Ages and into Early Modern Times....
, the Indus Valley units of length referred to above and the Mesopotamian cubit were used in the 3rd millennium BC
3rd millennium BC
The 3rd millennium BC spans the Early to Middle Bronze Age.It represents a period of time in which imperialism, or the desire to conquer, grew to prominence, in the city states of the Middle East, but also throughout Eurasia, with Indo-European expansion to Anatolia, Europe and Central Asia. The...
and are the earliest known units used by ancient peoples to measure length. The measures of length used in ancient India included the dhanus (bow), the krosa (cry, or cow-call) and the yojana
Yojana
A Yojana is a Vedic measure of distance used in ancient India. The exact measurement is disputed amongst scholars with distances being given between 6 to 15 kilometers ....
(stage).
The common cubit was the length of the forearm from the elbow to the tip of the middle finger. It was divided into the span of the hand (one-half cubit), the palm or width of the hand (one sixth), and the digit or width of the middle finger (one twenty-fourth) and the span or the length between the tip of little finger to the tip of the thumb. The Sacred Cubit, which was a standard cubit enhanced by an extra span—thus 7 spans or 28 digits long—was used in constructing buildings and monuments and in surveying in ancient Egypt. The inch
Inch
An inch is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in a foot...
, foot, and yard
Yard
A yard is a unit of length in several different systems including English units, Imperial units and United States customary units. It is equal to 3 feet or 36 inches...
evolved from these units through a complicated transformation not yet fully understood. Some believe they evolved from cubic measures; others believe they were simple proportions or multiples of the cubit. In whichever case, the Greeks and Romans inherited the foot from the Egyptians. The Roman foot (~296 mm) was divided into both 12 unciae (inches) (~24.7 mm) and 16 digits (~18.5 mm). The Romans also introduced the mille passus (1000 paces) or double steps, the pace being equal to five Roman feet (~1480 mm). The Roman mile
Mile
A mile is a unit of length, most commonly 5,280 feet . The mile of 5,280 feet is sometimes called the statute mile or land mile to distinguish it from the nautical mile...
of 5000 feet (1480 m) was introduced into England during the occupation. Queen Elizabeth I
Elizabeth I of England
Elizabeth I was queen regnant of England and Ireland from 17 November 1558 until her death. Sometimes called The Virgin Queen, Gloriana, or Good Queen Bess, Elizabeth was the fifth and last monarch of the Tudor dynasty...
(reigned from 1558 to 1603) changed, by statute, the mile to 5280 feet (~1609 m) or 8 furlongs, a furlong
Furlong
A furlong is a measure of distance in imperial units and U.S. customary units equal to one-eighth of a mile, equivalent to 220 yards, 660 feet, 40 rods, or 10 chains. The exact value of the furlong varies slightly among English-speaking countries....
being 40 rod (unit)
Rod (unit)
The rod is a unit of length equal to 5.5 yards, 5.0292 metres, 16.5 feet, or of a statute mile. A rod is the same length as a perch or a pole. In old English, the term lug is also used.-History:...
s (~201 m) of 5.5 yards (~5.03 m)each.
The introduction of the yard (0.9144 m) as a unit of length came later, but its origin is not definitely known. Some believe the origin was the double cubit, others believe that it originated from cubic measure. Whatever its origin, the early yard was divided by the binary method into 2, 4, 8, and 16 parts called the half-yard, span, finger, and nail. The association of the yard with the "gird" or circumference of a person's waist or with the distance from the tip of the nose to the end of the thumb of King Henry I
Henry I of England
Henry I was the fourth son of William I of England. He succeeded his elder brother William II as King of England in 1100 and defeated his eldest brother, Robert Curthose, to become Duke of Normandy in 1106...
(reigned 1100–1135) are probably standardizing actions, since several yards were in use in Britain.
There were also Rods, Poles and Perches for measurements of length. The following table lists the equivalents.
Length
12 lines = 1 inch
12 inches = 1 foot
3 feet = 1 yard
1760 yards = 1 mile
36 inches = 1 yard
440 yards = quarter mile
880 yards = half mile
100 links = 1 chain
10 chains = 1 furlong
8 furlongs = 1 mile
4 inches = 1 hand
22 yards = 1 chain
5.5 yards = 1 rod, pole or perch
4 poles = 1 chain
40 poles = 1 furlong
Typographical units
The use in typography of the point, which was one twelfth of a ligne in the customary French measures of the Ancien régimeUnits of measurement in France before the French Revolution
200px|thumb|right|Woodcut dated 1800 illustrating the new decimal units which became the legal norm across all France on 4 November 1800Before the Revolution French units of measurement were based on the Carolingian system, introduced by the first Holy Roman Emperor Charlemagne which in turn were...
, as a unit for measuring print type predates the metric system. Various typographic points were defined, including the Truchet point by Sébastien Truchet (1657–1729), the Fournier point by Pierre Simon Fournier
Pierre Simon Fournier
Pierre Simon Fournier was a French mid-18th century punch-cutter, typefounder and typographic theoretician. He was both a collector and originator of types”. Fournier's contributions to printing were his creation of initials and ornaments, his design of letters, and his standardization of type...
in 1737 and the Didot point by the Didot brothers, Francois Ambroise and Pierre Francois, in 1755 or 1767 or 1783, which was exactly two Truchet points. The point was first used in the United States in 1878 or 1872 by a Chicago type foundry (Marder, Luse, & Co.
Marder, Luse, & Co.
Marder, Luse, & Co. was founded in 1855 as the Chicago Type Foundry and Printer's Warehouse by C. G. Sheffield as branch of Elihu White's New York foundry, Farmer, Little & Co.. This was the first type foundry to operate in Chicago...
).
The point
Point (typography)
In typography, a point is the smallest unit of measure, being a subdivision of the larger pica. It is commonly abbreviated as pt. The point has long been the usual unit for measuring font size and leading and other minute items on a printed page....
was defined as 1/12 of a pica consisting of 1/6 of an inch truncated to thousandths of an inch (1/12 of 0.166 inches) in the USA in 1886 and was quickly adopted by Britain and its colonies;. This number has been approximated in various ways depending on the technology, prejudices, and information available to engineers involved in the production of typesetting machinery since then. Common approximations in use are 1/72.27 inch (now equal to 0.3514598 mm) and simply 1/72 of an inch. Other typographic points
Typographic unit
Typographic units are the units of measurement used in typography or typesetting. The traditional units are different from common metric units, as they were established earlier. Even though these units are all very small, across a line of print they add up quickly...
are used in other countries.
The pica in any of several related systems measures 12 points.
Units of mass
The grain was the earliest unit of mass and is the smallest unit in the apothecary, avoirdupoisAvoirdupois
The avoirdupois system is a system of weights based on a pound of 16 ounces. It is the everyday system of weight used in the United States and is still widely used to varying degrees by many people in Canada, the United Kingdom, and some other former British colonies despite the official adoption...
, Tower, and troy
Troy weight
Troy weight is a system of units of mass customarily used for precious metals, gemstones, and black powder.There are 12 troy ounces per troy pound, rather than the 16 ounces per pound found in the more common avoirdupois system. The troy ounce is 480 grains, compared with the avoirdupois ounce,...
systems. The early unit was a grain of wheat or barleycorn used to weigh the precious metals silver and gold. Larger units preserved in stone standards were developed that were used as both units of mass and of monetary currency. The pound
Pound (mass)
The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...
was derived from the mina used by ancient civilizations. A smaller unit was the shekel, and a larger unit was the talent. The magnitude of these units varied from place to place. The Babylonians and Sumerians had a system in which there were 60 shekels in a mina and 60 minas in a talent. The Roman talent consisted of 100 libra (pound) which were smaller in magnitude than the mina. The troy pound (~373.2 g) used in England and the United States for monetary purposes, like the Roman pound, was divided into 12 ounces, but the Roman uncia (ounce) was smaller. The carat is a unit for measuring gemstones that had its origin in the carob seed, which later was standardized at 1/144 ounce and then 0.2 gram.
Goods of commerce were originally traded by number or volume. When weighing of goods began, units of mass based on a volume of grain or water were developed. For example, the talent in some places was approximately equal to the mass of one cubic foot of water. Was this a coincidence or by design? The diverse magnitudes of units having the same name, which still appear today in our dry and liquid measures, could have arisen from the various commodities traded. The larger avoirdupois pound for goods of commerce might have been based on volume of water which has a higher bulk density
Bulk density
Bulk density is a property of powders, granules and other "divided" solids, especially used in reference to mineral components , chemical substances, ingredients, foodstuff or any other masses of corpuscular or particulate matter. It is defined as the mass of many particles of the material...
than grain. For example, the Egyptian hon was a volume unit about 11 per cent larger than a cubic palm and corresponded to one mina of water. It was almost identical in volume to the present U.S. pint (~473 mL).
The stone, quarter, hundredweight, and ton were larger units of mass used in Britain. Today only the stone continues in customary use for measuring personal body weight. The present stone is 14 pounds (~6.35 kg), but an earlier unit appears to have been 16 pounds (~7.25 kg). The other units were multiples of 2, 8, and 160 times the stone, or 28, 112, and 2240 pounds (~12.7 kg, 50.8 kg, 1016 kg), respectively. The hundredweight was approximately equal to two talents. The ton of 2240 pounds is called the "long ton". The "short ton" is equal to 2000 pounds (~907 kg). A tonne (t) is equal to 1000 kg.
Units of time and angle
Systems of measurement
A system of measurement is a set of units which can be used to specify anything which can be measured and were historically important, regulated and defined because of trade and internal commerce...
divided the day differently; other calendar
Calendar
A calendar is a system of organizing days for social, religious, commercial, or administrative purposes. This is done by giving names to periods of time, typically days, weeks, months, and years. The name given to each day is known as a date. Periods in a calendar are usually, though not...
s divided the year differently.
Metric conversion
The metric systemMetric system
The metric system is an international decimalised system of measurement. France was first to adopt a metric system, in 1799, and a metric system is now the official system of measurement, used in almost every country in the world...
was first described 1668, and officially adopted by France in 1799. Over the course of the 1800s and 1900s, it became the dominant system worldwide, with the largest exception being the United States.
See also
- Airy pointsAiry PointsAiry Points are used for precision measurement to support a length standard in such a way as to minimise bending or droop. The points are symmetrically arranged around the centre of the length standard and are separated by a distance equal to...
- Ancient Mesopotamian units of measurementAncient Mesopotamian units of measurementAncient Mesopotamian units of measurement originated in the loosely organized city-states of Early Dynastic Sumer. The units themselves grew out of the tradition of counting tokens used by the Neolithic cultural complex of the Near East. The counting tokens were used to keep accounts of personal...
- Greek Systems
- History of measurement systems in IndiaHistory of measurement systems in IndiaThe history of measurement systems in India begins in early Indus Valley Civilization with the earliest surviving samples dated to the 5th millennium BCE. Since early times the adoption of standard weights and measures has reflected in the country's architectural, folk, and metallurgical artifacts...
- Imperial unitImperial unitThe system of imperial units or the imperial system is the system of units first defined in the British Weights and Measures Act of 1824, which was later refined and reduced. The system came into official use across the British Empire...
- Mesures usuellesMesures usuellesMesures usuelles were a system of measurement introduced by Napoleon I in 1812 to act as compromise between the metric system and traditional measurements...
- Megalithic yardMegalithic YardA Megalithic Yard is a unit of measurement, about , that some researchers believe was used in the construction of megalithic structures. The proposal was made by Alexander Thom as a result of his surveys of 600 megalithic sites in England, Scotland, Wales and Britanny...
- Pseudoscientific metrologyPseudoscientific metrologySome approaches in the branch of historic metrology are highly speculative and can be qualified as pseudoscience. Interest in ancient metrology was triggered by research into the various Megalith building cultures and the Great Pyramid of Giza.-Origins:...
- SISiSi, si, or SI may refer to :- Measurement, mathematics and science :* International System of Units , the modern international standard version of the metric system...
- Systems of measurementSystems of measurementA system of measurement is a set of units which can be used to specify anything which can be measured and were historically important, regulated and defined because of trade and internal commerce...
- Units of measurementUnits of measurementA unit of measurement is a definite magnitude of a physical quantity, defined and adopted by convention and/or by law, that is used as a standard for measurement of the same physical quantity. Any other value of the physical quantity can be expressed as a simple multiple of the unit of...
- U.S. customary unit
- Weights and measures
- Winchester measureWinchester measureWinchester measure is a set of legal standards of volume defined in the city of Winchester, England during the tenth century and in use, with some modifications, until the present day.-National standard:...
Further reading
- , Measures and Weights in the Islamic World. An English Translation of Professor Walther Hinz's Handbook “Islamische Maße und Gewichte“, with a foreword by Professor Bosworth, F.B.A. Kuala Lumpur, ISTAC, 2002, ISBN 983-9379-27-5. This work is an annotated translation of a work in German by the late German orientalist Walther Hinz, published in the Handbuch der Orientalistik, erste Abteilung, Ergänzungsband I, Heft 1, Leiden, The Netherlands: E. J. Brill, 1970.
- Scales and Weights: A Historical Outline, Bruno Kisch. (New Haven: Yale University Press, 1965. Based in part on the Edward C. Streeter collection at Yale Medical Historical Library