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