It is, however, during the Middle Minoan age, the centre point of which corresponds with the XIIth Egyptian dynasty, according to the Sothic system of dating, c. 2000-1850 B.C., that a systematized pictographic or hieroglyphic script makes its appearance which is common both to signets and clay tablets.
But the year of 365 days lost one day in four years of the Sothic or Julian year, so that in 121 Egyptian years New Years clay fell a whole month too early according to the seasons, and in 1461 years a whole year was lost.
This Sothic period r era of 1460 years, during which the Egyptian New Years day travelled all round the Sothic year, is recorded by Greek and Roman writers at least as early as the 1st century B.C. The epagomenal days appear on a monument of the Vth Dynasty and in the very ancient Pyramid texts.
Whether any earlier attempt was made to adjust the civil to the solar or Sothic year in order to restore the festivals to their proper places in the seasons temporarily or otherwise, is a question of great importance for chronology, but at present it remains unanswered.
Of these, the Sothic date furnished by a calendar in the Ebers Papyrus of the 9th year of Amenophis I.
Another Sothic date of the 7th year of Senwosri III.
Professor Petrie, however, thinks it best, while accepting the evidence of the Sirius date, to suppose further that a whole Sothic period of 1460 years had passed in the interval, making a total of 1650 years for the six dynasties in place of 220 years.
To the present writer it seems that Meyers chronology provides a convenient working theory, but involves such an improbability in regard to the interval between the XIIth and the XVIIIth Dynasties that the interpretation of the Sothic date on which it is founded must be viewed with suspicion until clear facts are found to corroborate it.
P. 48, confirms the Sothic date for the XIIth Dynasty in some measure, but it belongs to the same age, and therefore its evidence would be equally vitiated with the other by any subsequent alteration in the Egyptian calendar.
Before the discovery of the Kahun Sothic date, Professor Petrie Viedemann Meyer Petrie Breasted Maspero 1884.1884.1905-1906.1906.1904.
Others are grounded on the dates of certain operations which are likely to have taken place at particular seasons of the year so that they can be roughly calculated on the Sothic basis, others on Manethos figures, average lengths of reigns, evidence of the Turin Papyrus, &c.
Page 79 shows the chronology of the first nineteen dynasties, according to recent authorities, before and after the discovery of the Kahun Sothic date.
A new Sothic cycle began in A.D.