Calotte zodiacale

Domed cap, divided into 12 equal sections corresponding to the months of the year, months of 30 days. Each section is engraved with 3 words superimposed, in Greek letters:
- on the outer line are the 12 Egyptian months
- on the middle line, the signs of the zodiac
- on the inner line, the 12 months of the Roman Julian calendar.
In each of the 12 sections, there are 5 notches corresponding to 6 divisions of the decan.
The cap can be read starting with Thôth, the first month of the Egyptian calendar (August 28 or 29), which coincided with the beginning of the Nile flooding and the sowing.