Roman timekeeping

In Roman timekeeping, a day was divided into periods according to the available technology. Initially, the day was divided into two parts: the ante meridiem (before noon) and the post meridiem (after noon). With the advent of the sundial circa 263 BC, the period of the natural day from sunrise to sunset was divided into twelve hours.^[1]

^ Aldrete, Gregory S. (2004). Daily Life in the Roman City: Rome, Pompeii and Ostia. Greenwood Publishing Group. pp. 241-244. ISBN 978-0-313-33174-9. Retrieved 24 December 2019.

[aldrete-1] Aldrete, Gregory S. (2004). Daily Life in the Roman City: Rome, Pompeii and Ostia. Greenwood Publishing Group. pp. 241-244. ISBN 978-0-313-33174-9. Retrieved 24 December 2019.

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