Answer:
The Ancient Egyptian Calendar was used for chronology by Ptolemy.
Step-by-step explanation:
The ancient Egyptians developed a solar calendar with three seasons in a year of 365 days. The twelve months were divided into three different sets of four months. Throughout a large period of Egyptian history, the months were not known by their names and it was only during the Middle Kingdom that each month get a Hellenized name. These Hellenized names were used for chronology by Ptolemy in his works such as Almagest.