Black cubit

Black cubit , Cubitus nigri , was a measure of length and is considered an Arabic measure. It was determined by the caliph Al-Mamun in the 9th century to measure the Arabian Gulf ( Red Sea ) as a valid measure. The explanation of the name in the many traditions can be assigned to the legends. Example: the length of the forearm of a dark-skinned slave is said to have been the measuring standard. The length of the ulna corresponded to 27 times the length of the six barley grain width.

1 cubit (black) = 0.52 meters ; according to Boeckh = 239.69 Parisian lines = 0.5407 meters; after Karsten u. a. = 0.54189 meters

literature

Erna Padelt, Hansgeorg Laporte: Units and magnitudes of the natural sciences. Fachbuchverlag, Leipzig 1967, p. 30.

Individual evidence

↑ August Böckh: Metrological investigations into weights, coin feet and measures of antiquity in their context. Veit and Comp., Berlin 1838, p. 247 ( Google Books ).
^ Gustav Karsten, Friedrich Harms, Georg Daniel Eduard Weyer : General Encyclopedia of Physics. Volume 1: Introduction to Physics. Leopold Voss, Leipzig 1869, p. 430 ( Google Books ).

[1] August Böckh: Metrological investigations into weights, coin feet and measures of antiquity in their context. Veit and Comp., Berlin 1838, p. 247 ( Google Books ).

[2] Gustav Karsten, Friedrich Harms, Georg Daniel Eduard Weyer : General Encyclopedia of Physics. Volume 1: Introduction to Physics. Leopold Voss, Leipzig 1869, p. 430 ( Google Books ).