An Ancient Egyptian Mathematical Photo Album: Calendars

Author(s): 
Cynthia J. Huffman (Pittsburg State University)

 

Egyptian hieroglyph numerals were also used in recording time. The Egyptian annual calendar consisted of five extra days and twelve months (with each month having three weeks and each week containing ten days) for a total of 365 days. The year was also broken down into three seasons of four months each: inundation called Akhet (when the Nile annually flooded depositing fertile top soil, June to September); emergence or growing season called Peret (October to February); and harvest season called Shemu (March to May) [Brier 2016].

Figure 11 is from a calendar at the Kom Ombo Temple. The circle on the right of each panel is the sun disk determinative to indicate that the writing presents a date. From the top, we see 27, 28, 29 (the circle with the line across represents 9), the 30th day of the last month of the harvest season, the first day of the first month of inundation, 2, 3, and so on.

The Egyptians did not keep a running count of the years. As each new pharaoh began his or her reign, the year count would reset. So, a particular date would be given as the year of the reign of the current pharaoh, the month of the season, and the day.

Ancient Egyptian calendar in hieroglyphs.
Figure 11. Portion of a calendar showing hieroglyph numerals from the Kom Ombo Temple (180–47 BCE).