A cubit is the first recorded unit of length and was one of many different standards of measurement used through history.
It was originally based on measuring by comparing to one's forearm length. The Egyptian hieroglyph for the unit shows this symbol. It was employed through Antiquity, the MiddleAges up to the Early Modern Times, especially for measuring cords and textiles, but also for timbers, stone and volumes of grain.
The Egyptian cubit was not subdivided into centimetres or inches, but into palms and digits. The cubit was subdivided into 7 'palms' of 4 'digits', making 28 parts in all. The distance between thumb and another finger to the elbow on an average person measures about 24 digits or 6 palms or 1½ feet. This is about 45 cm or 18 inches. This is sometimes referred to as a "natural cubit"^{[citation needed]} of 1½ feet and was used in the Roman system of measures and in different Greek systems.
Over time, various cubits and variations on the cubit have measured:
From late Antiquity, the Roman ulna, a fourfoot cubit (about 120 cm) is also attested. This length is the measure from a man's hip to the fingers of the outstretched opposite arm.
The English yard could be considered to be a type of cubit, measuring 12 palms, ~90 cm, or 36 inches (3.00 ft). This is the measure from the middle of a man's body to his fingers, always with outstretched arm. The English ell is essentially a kind of great cubit of 15 palms, 114 cm, or 45 inches (3.75 ft).
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The cubit—the approximate length of the forearm—is among the first recorded units of length used by an ancient people.
The earliest attested standard measure is from the OLD KINGDOM pyramids of Egypt and was called the royal cubit (mahe). The RC was 523 to 525 mm (20.6 to 20.64 inches) in length^{[2]}, and was subdivided into 7 palms of 4 digits each, for a 28part measure in total. Secure evidence for the RC unit is known from OLD KINGDOM architecture, from at least as early as the construction of the Step Pyramid of Djoser from around 2,700 B.C.^{[3]}
In 1916, during the last years of Ottoman Empire and in the middle of WWI, the German Assyriologist Eckhard Unger found a copperalloy bar during excavation at Nippur from c. 2650 BC. which he claimed was a measurement standard. This irregularly formed and irregularly marked graduated rule supposedly defined the Sumerian cubit as about 518.5 mm or 20.4 inches, although this does not agree with more secure evidence from the statues of Guduea from the same region. A 30digit cubit known as a kus was nevertheless known from the 2nd millennium B.C., with a digitlength of about 17.28 mm (more than 0.68 inch).
Old Egyptian geometers could calculate the square root of two from the value of the hypotenuse of a cubit. This wellattested old Egyptian unit was known as the "construction remen" and used a good approximation: .
Heb. 'ammah; i.e., "mother of the arm," the forearm, is a word derived from the Latin cubitus, the lower arm. It is difficult to determine the exact length of this measure, from the uncertainty whether it included the entire length from the elbow to the tip of the longest finger, or only from the elbow to the root of the hand at the wrist. The probability is that the longer was the original cubit. The common computation as to the length of the cubit makes it 20.24 inches for the ordinary cubit, and 21.888 inches for the sacred one. This is the same as the Egyptian measurements.
A rod or staff the measure of a cubit is called in Jdg 3:16 gomed, which literally means a "cut," something "cut off." The LXX. and Vulgate render it "span."
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Cubit is the name for any one of many units of measure used by various ancient peoples and is among the first recorded units of length.
The cubit is based on measuring by comparing – especially cords and textiles, but also for timbers and stones – to one's forearm length. The Egyptian hieroglyph for the unit shows this symbol. It was employed consistently through Antiquity, the Middle Ages up to the Early Modern Times.
The distance between thumb and another finger to the elbow on an average person and measures about 24 digits or 6 palms or 1½ feet. This is about 45 cm or 18 inches. This socalled "natural cubit" of 1½ feet is used in the Roman system of measures and in different Greek systems.
Over time, units similar in type to the cubit have measured:
From late Antiquity, the Roman ulna, a fourfeetcubit (about 120 cm) is also attested. This length is the measure from a man's hip to the fingers of the outstretched opposite arm.
The English yard could be considered to be a type of cubit, measuring 12 palms, ~90 cm, or 36 inches (3.00 ft). This is the measure from the middle of a man's body to his fingers, always with outstretched arm. The English ell is essentially a kind of great cubit of 15 palms, 114 cm, or 45 inches (3.75 ft).
