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Cubit is the name applied to the set of units of measure longer than a remen but shorter than an elle. Cubits generally have a long and a short form with the short form 5 hands or 6 palms and the long form 6 hands or 7 palms. The range of lengths that can be applied to cubits thus ranges from 1 1/2 to 2 feet. Cubit measures were used in Mesopotamia, Egypt, throughout the Ancient Near East, Greece, Persia, Rome, and Europe.

Similar but unrelated measures that may have been about the length of a human forearm were used by many other cultures. Cubit measures include the Roman cubit of 444 mm, The Egyptian short cubit of 450 mm, the Greek cubit of 463 mm the Assyrian cubit of 494 mm, The Sumerian cubit of 500 mm, The Egyptian royal cubit of 524 mm, the Talmudist cubit of 555 mm and the Palestinian cubit of 641 mm from AE Berriman "Historical Metrology" London, 1953

It has been said that when cubits originating in Western Asia, Greece and Africa are compared the difference are small because the cubit had been standardized by the Hellenistic era. The cubit is 18 inches in Burma and 22 inches in Somalia. A standard measure was employed as early as c. 2750 BC at Saqqara.

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In recent years the analytic geometry of the Egyptians unit fraction algorythms have become interesting. The mathematics underlying the solutions of the Egyptians who first attacked the problem in the Rhind Papyrus are once again being studied because of their implications for continued fractions. This represents a construction by an Egyptian architect which dates back to the 3rd millennium BC which solves the problem by the use of two different coordinate systems. The problem really dates back to the invention of geometry and has occupied mathematicians for millennia. It was not until 1882 that the impossibility was proven rigorously, though even the ancient geometers had a very good practical and intuitive grasp of its intractability. It should be noted that it is the limitation to just compass and straightedge that makes the problem difficult.

The royal cubit was subdivided into 7 palms of 4 digits, 28 digits in total. The ordinary cubit of of 6 palms, remen of 5 palms, foot of 4 palms, nibw or double foot of 8 palms were part of the same standard system.Standard Egyptian cubits survive from later dynasties.

Along with other body measures such as fingers, palms, hands, spans, and feet, cubits are among the earliest recorded units of length. Although the earliest written references to standards of measure are more concerned with agricultural measures, by the pyramid age, c 3000 BC, accurate cubit rulers begin to be found in Egypt and many artifacts including buildings are measured in cubits. By the Old Babylonian period rules and rods are bound throughout Mesopotamia.

Palm based cubits
While several different standard rules and Nileometers survive from the Old Kingdom of Egypt, it has been estabished from a surviving inscription that a standard measure was employed as early as c. 2750 BC at Saqqara. From archaeological evidence this standard was in use throughout most of the land irrigated by Nile as early as the predynastic Naquadda II period. From other archaeological evidence the standard in the range of 523 to 525 mm in length, and was subdivided into fingers, palms, hands, spans, feet of 4 palms, remen of 5 palms, ordinary cubits of 6 palms, and royal cubits of 7 palms. A longer unit known as the nibw was litterally 2 feet or 8 palms. Multiples of royal cubits were the hayt of 10 royal cubits and the khet of 100 royal cubits. Many other cultures used palm based cubits including the Romans and the people who wrote the Bible.


 * The ordinary Roman cubitus was 444 mm (17.5 in)
 * The ordinary Biblical cubit was 457.2 mm ( 18").

Hand based cubits
In Mesopotamia cubits were divided into fingers and hands. A foot cubit of 3 hands would be the same length as a foot or land cubit (mh t3) of 4 palms but count 15 fingers instead of 16. A cubit of 6 hands would be the same as a nibw of 8 palms or 2 feet.

Many other cultures used hand based cubits as well. Persian cubits were actually remen of 370 mm.

Since the Greek city states had several different feet and each cubit was composed of the same fingers and hands that added up to the foot, the length of the cubbit can be determined from the length of the foot.


 * The Attic foot was 304.8 mm so the Attic cubit was 508 mm
 * The Athenian foot was 316 mm so the Athenian cubit was 526.66 mm
 * The Ionian foot was 296 mm so the Ionian cubit was 493.33 mm

The cubit of King Gudea of Lagash (an ancient Mesopotamian city-state) was 500 mm (19.68 inches). In ancient Israel during the First Temple period, one cubit was 428 mm. During the Second Temple period, an Egyptian cubit of 450 mm was in general use, but in the sacred areas of the temple another cubit of 437 mm was used. (See Biblical Archaeology Review, March-April 1983, and Newsletter and Proceedings of the Society for Early Historical Archaeology, issue 159.)