Cubit

thumb|Egyptian cubit rod in the [[Liverpool World Museum]]

thumb|Cubit rod of [[Maya (Egyptian)|Maya, 52.3 cm long, 1336–1327 BC (Eighteenth Dynasty)]]

The cubit is an ancient unit of length based on the distance from the elbow to the tip of the middle finger. It was primarily associated with the Sumerians, and the Egyptians. The term cubit is found in the Bible regarding Noah's Ark, the Ark of the Covenant, the Tabernacle, the gallows of the Book of Esther, the Miraculous catch of fish and Solomon's Temple. The common cubit was divided into 6 palms × 4 fingers = 24 digits. Royal cubits added a palm for 7 palms × 4 fingers = 28 digits. These lengths typically ranged from , with an ancient Roman cubit being as long as .

Cubits of various lengths were employed in many parts of the world in antiquity, during the Middle Ages and as recently as early modern times. The term is still used in hedgelaying, the length of the forearm being frequently used to determine the interval between stakes placed within the hedge.

Etymology

The English word "cubit" comes from the Latin noun "elbow", from the verb "to lie down", from which also comes the adjective "recumbent".

Ancient Egyptian royal cubit

The ancient Egyptian royal cubit () is the earliest attested standard measure. Cubit rods were used for the measurement of length. A number of these rods have survived: two are known from the tomb of Maya, the treasurer of the 18th dynasty pharaoh Tutankhamun, in Saqqara; another was found in the tomb of Kha (TT8) in Thebes. Fourteen such rods, including one double cubit rod, were described and compared by Lepsius in 1865. The Classical Mesopotamian System also has a proportional relationship, by virtue of standardized commerce, to Bronze Age Harappan and Egyptian metrologies.

In 1916, during the last years of the Ottoman Empire and in the middle of World War I, the German assyriologist Eckhard Unger found a copper-alloy bar while excavating at Nippur. The bar dates from and Unger claimed it was used as a measurement standard. This irregularly formed and irregularly marked graduated rule supposedly defined the Sumerian cubit as about .

Late Assyrian cubits

Ancient Assyrian units of measure appear to exhibit significant variability. However, based on analysis of careful measurement of sculptured slabs and figures from Khorsabad, dating to the time of Sargon II, now held in Western museums, it appears that standard measures did exist. This analysis, together with information from cuneiform documents from the period, confirm the existence of three Late Assyrian cubits or "kus" as the measure was called in Assyrian literature:

The standard cubit (approximately ), used in most normal situations.
The big cubit () is believed to have been reserved for representations of religious and mythological beings.
The rare cubit of the king () is believed to have been used for representations of the king.

Biblical cubit

The standard of the cubit () in different countries and in different ages has varied. This realization led the rabbis of the 2nd century CE to clarify the length of their cubit, saying that the measure of the cubit of which they have spoken "applies to the cubit of middle-size". In this case, the requirement is to make use of a standard 6 handbreadths to each cubit, and which handbreadth was not to be confused with an outstretched palm, but rather one that was clenched and which handbreadth has the standard width of 4 fingerbreadths (each fingerbreadth being equivalent to the width of a thumb, about 2.25 cm).

This puts the handbreadth at roughly , and 6 handbreadths (1 cubit) at . Epiphanius of Salamis, in his treatise On Weights and Measures, describes how it was customary, in his day, to take the measurement of the biblical cubit: "The cubit is a measure, but it is taken from the measure of the forearm. For the part from the elbow to the wrist and the palm of the hand is called the cubit, the middle finger of the cubit measure being also extended at the same time and there being added below (it) the span, that is, of the hand, taken all together."

Rabbi Avraham Chaim Naeh put the linear measurement of a cubit at . Avrohom Yeshaya Karelitz (the "Chazon Ish"), dissenting, put the length of a cubit at .

Rabbi and philosopher Maimonides, following the Talmud, makes a distinction between the cubit of 6 handbreadths used in ordinary measurements, and the cubit of 5 handbreadths used in measuring the Golden Altar, the base of the altar of burnt offerings, its circuit and the horns of the altar.

Ancient Rome

In ancient Rome, according to Vitruvius, a cubit was equal to Roman feet or 6 palm widths (approximately ). A 120-centimetre cubit (approximately four feet long), called the Roman ulna, was common in the Roman empire, which cubit was measured from the fingers of the outstretched arm opposite the man's hip.<sup>; also, </sup><sup>with</sup>

Islamic world

In the Islamic world, the cubit () had a similar origin, being originally defined as the arm from the elbow to the tip of the middle finger. Several different cubit lengths were current in the medieval Islamic world for the unit of length, ranging from , and in turn the was commonly subdivided into six handsbreadths (), and each handsbreadth into four fingerbreadths ().

The Modulor is another human based measurement devised by the Swiss-born French architect Le Corbusier (1887–1965).

Cubit arm in heraldry

thumb|upright|A heraldic cubit arm, [[Dexter and sinister|dexter, vested and erect]]

A cubit arm in heraldry may be dexter or sinister. It may be vested (with a sleeve) and may be shown in various positions, most commonly erect, but also fesswise (horizontal), bendwise (diagonal) and is often shown grasping objects. It is most often used erect as a crest, for example by the families of Poyntz of Iron Acton, Rolle of Stevenstone and Turton.

References

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Bibliography

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Petrie, Sir Flinders (1881). Pyramids and Temples of Gizeh.
Stone, Mark H., "The Cubit: A History and Measurement Commentary", Journal of Anthropology , 2014