Re: Why not 13 months? (Was La Systeme Metrique)

Frank Joseph Yurco (
Wed, 12 Jul 1995 17:47:44 GMT

In the whole debate about the calendar, no one has mentioned whence the
12 month calendar derives. I was developed in ancient Egypt, as the Sothic
Calendar, with 12 months of 30 days each, and 5 days added at the end,
to give 365 days. In the Ptolemaic Period, around 270 B.C., the concept
of the leap year was discovered, and every four years a sixth day was added.
This was the calendar that Julius Caesar adopted for Roman use after he
had visited Egypt, and of course, what the Romans did was to lengthen some
months to 31 days, and thus eliminated the need to add the extra five days.

Frank J. Yurco
University of Chicago

Frank Joseph Yurco