Danna (Mesopotamian)

Danna (Sumerian) or Beru (Akkadian) is a word denoting a unit of time consisting of two hours.^[1] There were twelve Danna in a day. Danna were first used around 2400 BC.^[2]

Change in length and decline

In Hellenistic times the Danna was halved with the introduction of the temporal hours and the number of daylight hours increased from twelve to twenty-four. The conversion was based on the ancient Egyptian precursors of the 24 seasonally - equal hours. A 24-hour division of the day could not be proven in inscriptions on Babylonian tablets, which is why the Babylonians cannot be used as the originators of the 24-hour division of the day.^[3]

See also

• Unequal hours
• Equinoctial hours

References

1. "Sumerian Questions and Answers". www.sumerian.org. Retrieved 2023-01-29.
2. Vgl. François Thureau-Dangin: Textes de l'époque d'Agadé <Fouilles d'Ernest de Sarzec en 1895> - Inventaire des tablettes de Tello (Teil 1) -, Leroux, Paris 1910, 11, 1175; Otto Neugebauer: Astronomy and history - Selected essays -, Springer, New York 1983, S. 8.
3. Vgl. Friedrich-Karl Ginzel: Handbuch der mathematischen und technischen Chronologie, Bd. 1 - Zeitrechnung der Babylonier, Ägypter, Mohammedaner, Perser, Inder, Südostasiaten, Chinesen, Japaner und Zentralamerikaner -, Deutsche Buch-Ex- und Import, Leipzig 1958 (Nachdruck Leipzig 1906), S. 123.