Cubit

The cubit is an ancient unit based on the forearm length from the middle finger tip to the elbow bottom. 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 hedge laying, the length of the forearm being frequently used to determine the interval between stakes placed within the hedge.

The English word "cubit" comes from the Latin noun cubitus "elbow", from the verb cubo, cubare, cubui, cubitum "to lie down", from which also comes the adjective "".

The Ancient Egyptian royal cubit (meh niswt) 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. These cubit rods range from 523.5 to 529.2 mm (20.61 to 20.83 in) in length, and are divided into seven palms; each palm is divided into four fingers and the fingers are further subdivided.

Hieroglyph of the royal cubit, meh niswt

Early evidence for the use of this royal cubit comes from the Early Dynastic Period: on the Palermo Stone, the flood level of the Nile river during the reign of the Pharaoh Djer is given as measuring 6 cubits and 1 palm. Use of the royal cubit is also known from Old Kingdom architecture, from at least as early as the construction of the Step Pyramid of Djoser in around 2,700 BC.

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