Temples, Tombs & Hieroglyphs_ A Popular History of Ancient Egypt - Barbara Mertz [18]
The lunar calendar worked admirably for a simple agricultural people; but as society became more complex, it was seen to have disadvantages. Every new month had to be established by observation, and no one knew in advance whether it would have thirty days or twenty-nine. At the end of the lunar year there would be a space of days, even weeks, before the opening of the new year, which was signalized by the rising of Sirius. So some busy bureaucrat decided, with royal approval, to set up another year whose exact length would be known in advance. This is called the “civil calendar,” and it is the distant ancestor of the one we use. It had twelve months of thirty days each, with five “intercalary” days at the end of the year. We don’t know how this unknown genius arrived at the number 365; he might have counted the days between successive risings of Sirius or he might have averaged out the number of days that elapsed between Inundations over a period of years.
Even this solution to the problem of time has a difficulty, which the reader has probably noticed. The true solar year does not have 365 days, but 365 and a quarter and then some. Hence, if the “Opening of the Year” occurred on day one, month one, when the civil calendar was first set up, four years later it would fall on day two, month one. A period of 1,460 years (four times 365) constituted what we call a “Sothic cycle” and brought the rising of Sirius back to “day one, month one” of the civil calendar once again.
There’s a lot more one can say about the calendars of ancient Egypt, but I am not that one. What really matters for our purpose is the Sothic cycle. From time to time the Egyptians saw fit to mention the rising of the Dog Star in connection with a date of their civil calendar. Now we know, from Roman sources, that a Sothic cycle—the coincidence of the rising of the star and the first day of the civil calendar—began in A.D. 139. By a simple process of arithmetic we can calculate that the previous cycle started in 1322 B.C., and the one before that in 2782 B.C. (Bear in mind that there is no year zero.) We have a mention of a Sothic rising, with date, in the Twelfth Dynasty, and another in the Eighteenth. Hence we can establish these events in terms of our own time scheme with relative accuracy. Why not absolute? Because we don’t know where the observations were taken. It makes a difference. Still, the variance is only a few years one way or the other. Knowing the dates of the Twelfth and Eighteenth Dynasties enables us to fix the approximate length of the confused period between these two stable periods.
We do not have, as yet, any astronomical reference from the Old Kingdom. There are two major documents that attempt to give a king list, with dates, for the Old Kingdom. One of them is in pieces and the other is in fragments.
The fate of the Turin Papyrus is told in a story that may be apocryphal, but whose general spirit is unhappily too typical of the early days of archaeology. The papyrus was complete when it was discovered in 1823 by a gentleman named Bernardino Drovetti, who stuck it into a jar that he tied around his waist. He then rode off to town on his donkey. The gait of a donkey being what it is, Egyptologists have been pushing the pieces of the papyrus around ever since, and cursing Drovetti as they do so. The other document, the Palermo Stone, is equally fragmented, though its material would seem so much more durable. Several bits