Hi Graham,

Accordingly, the oldest calendar system in use today is a intercalated lunar-solar system, the Hebrew calendar, and it began in the year 3761 BCE if I remember correctly.

If, for the sake of argument we accept this date it shows that the "levant" people were aware of lunar and solar cycles, why then should we expect the Egyptians to be in the dark? we don't or I don't. My best guess would be that because the moon is mostly visible at night along with the "stars" the lunar cycle was associated with the gods of the celestial realm, and the archaic Egyptians originally calculated the "feasts" and ritual sacrafices based on lunar cycles.

Knowing that Jericho was an agri settlement we can assume that solar cycles were at least known and observed by them ca. 7000 BCE, its my belief that naturally solar worship derives its origin from crop growing communities and not the nomadic tribes (neolithic hunter gatherers). In contrast hunter gatherers did not grow crops and had no need for solar calculation, but if they had deities they more than likely were associated through or by the moon and its cycles. Thus introducing crops required the introduction of solar worship, creating a natural conflict of interests not only for feasts and rituals but also for deciding which one, the moon or the sun, was more important. I have this fancy idea that the introduction of agriculture to the archaic tribes of the nile valley and Delta is what ultimately forced the unification of Upper and Lower Egypt, that the conflicts were spawned by competition of theological order between solar and lunar deities.

Mathematically over time an observer would find synchronizing lunar cycles that aligned with solar cycles, the most obvious synchronization could easily have been what we call the meton (Greek) cycle ~ 19 solar years equals 235 synodic lunar months; imagine if the solution to end arguments (warfare?) was to prove the moon and the sun were related using their respective cycles. However, an interesting correlation occurs when you calculate a 365.25 stellar year (sothis) cycle every 20 years ~ 365.25 x 20 = 7305 days and 7305 - 365 (civil calendar year) equals 235 synodic lunar months or 1 meton cycle [the moon returns to its exact phase and location each meton cycle]. So, mathematically using base 10 the synchronization of a Lunar, solar, civil and stellar cycle can be reached in 20 stellar year cycles, a very simple solution that the Hebrews decided against, the reality is that the Hebrew calendar is perhaps the most complicated system to grasp but it is by far the most accurate of any calendar system ever invented.

360 is a nice number for many reasons, as a suggestion, I ponder the idea; if you look at the symbols used for each solar month being lunar symbols how does one arrive at 360 days aligning with lunar cycles? you dont, you need to add 5 days and you would still fall short of 365 by 5 days because the difference per year is marginally 10-11 days (10.88 days). So, if the majority of archaic tribes in the nile valley are using a lunar calendar based on raw lunar cycles a year would equal roughly 355 days. The introduction of solar worship to these people would require them to adopt a 365 day year. Using simple math provides 360 days as a compromise that would accomodate 12 divisions (i.e. the twelve lunar months), the three seasons and it would provide the annual feastivals of Hrjw rnpt to round out 365 days. Calendars are large time pieces relative to the cycles of the universe, they are always adjusted or changed, a system used in the Old Kingdom could have easily been replaced by a system of the Middle Kingdom and so on. I would say that 360 is a perfect divisional compromise that helped fuse lunar and solar cycles, thus it was math based with an emphasis on serving the ritual and agricultural needs of a people emerging from neolithic survival as hunter gatherers. Geometry, in my opinion, had nothing to do with calendars though there is 360^2 = 355 x 365

Just for the record, I do not ascribe to Parker's "Sothic" calendar scheme, I agree with M. Clagett's analysis that there just is no hard evidence that clearly substantiates it use as a "fixed" double calendar system (civil ~ stellar) that cycles every 1,461 civil years; it requires that it survived the first and second intermediate periods and as a group, the Old Kingdom tomb invocation lists could not work with it unless, as Parker attempts to do, an older lunar calendar was scraped [before the Old Kingdom] for a new lunar calendar that used intercalary months periodically, something that has zero evidence to support it.

Best Regards,

B.A. Hokom