34 



NATURE 



[November lo, 1892 



has followed from the inquiries of chronologists that in 

 this year the ist of Thoth took place on July 20 (Julian), 

 the date originally of the heliacal rising of Sirius, the 

 beginning of the year. 



This being so,' then, in the year 23 A.D.— in which 

 the Alexandrine reform of the calendar, of which more 

 presently, was introduced— the ist of Thoth would take 

 place on August 29, a very important date. Censorinus 

 also said that in his own time (a.d. 238) the ist of Thoth 

 of the vague year fell on June 25. Fig. 5 will show the 

 connection of these three dates in reference to the vague 

 year. The relations of the statements made as to the 

 years 139 and 238 are very clearly discussed by Dr. 

 Oppolzer. 



Oppolzer, then, being satisfied as to the justice of 

 taking the year 139 a.d. as a time of coincidence of the 

 fixed and vague years — the latter being determined alone 

 by the heliacal rising of Sirius, and, be it remembered, not 

 by the solstices— calculated with great fulness, using Le- 

 verrier's modern values, the years in which, in the various 

 Egyptian latitudes, chiefly taking Memphis (lat. 30'') and 

 Thebes (lat. 25°), the coincidence between the two Thoths 

 occurred in the previous periods of Egyptian history. He 

 finds these dates for latitude 30° as follow : — 



Now the date which Oppolzer gives for the coincidence 

 which is nearest the date we had previously determined 

 at 270 B.C. is 139 A.D. There is a difference of 409 years. 



The question is. Can this fundamental difference be ex- 

 plained ? I think it can. 



In the first place, it is beyond doubt that, in the inter- 

 val between the Ramessids and the Ptolemies, the 

 calendar, even supposing the vague year to have been 

 used and to have been retained, had been fundamentally 

 altered, and the meanings of the hieroglyphics of the 

 tetramenes had been changed — in other words, the desig- 

 nations of the three seasons had been changed. 



On this point I quote Krall in a note.^ 



' It should be observed that a distinction is made between the Julian 

 and the historical year. This comes from the fact that when astronomical 

 phenomena are calculated for dates B.C., it must be remembered that chrono- 

 logists are in the habit of designating by i, or rather by - i, the first 

 year which precedes the instant of time at which the chronological year com- 

 menced, while astronomers mark this year in their tables by o. It follows, 

 therefore, that the rank of any year B.C. is always marked by an additional 

 unit in the chronological dates. For the Christian era, of course, chronologists 

 and astronomers work in the same way. The following table, given by Biot, 

 exhibits the connection between these two methods. In the latter Biot shows 

 the leap-years marked B, and the corresponding years in the Scaligerian 

 chronological period are also given. 



Dates of Julian Years commencing on January i. 

 According to According to Corresponding 



Chronologists. Astronomers. years of the period 



of Scaliger. 



-6 -s 4708 



-5B -4B 4709 



-i-s 



-1-5 



4718 



^ Loc. cit. p. 29. " It is well known that the interpretation of the seasons 

 and the months given by Champollion was opposed by Brugsch, who pro- 

 pounded another, which is now universally adopted by experts. Something 

 has happened here which is often repeated in the course of Egyptian history 

 — the signs have changed their meaning. Under the circumstance that the 

 vague year during 1461 years wanders through the seasons in a great cycle, it 



NO. 1202, VOL. 47] 



The three hieroglyphic signs used for the tetramenes 

 are supposed to represent water, flowers, and a barn, and 

 the natural order would be that the first should represent 

 the inundation, the second the sowing which succeeds 

 it, and the last harvest time. If this be conceded, the 

 initial system would have had the month Thoth con- 

 nected with the water sign, as Thoth in early Egyptian 

 times was the first inundation month. But in the times 

 of the Ramessids even this is not so. Thoth has the 

 sowing sign assigned to it. In the time of the Ptolemies 

 the flood is no longer in Thoth, but in Pachons, and 

 Pachons has the barn sign attached to it, while the month 

 Thoth is marked by the water sign, thereby bringing 

 back the hypothetical relation between the name of the 

 month and the sign, although, as we have seen, Thoth is 

 no longer the flood month. 



Egyptologists declare that all or at least part of this 

 change took place between the periods named ; they are 

 undoubtedly justified as regards a part. 



At one point in this interval we are fortunately supplied 

 with some precise information. In the year 238 B.C. 

 a famous decree was published, variously called the decree 

 of Canopus and the decree of Tanis, since it was inscribed 

 on a stone found there. 



It is perfectly clear that one of the functions of this 

 decree was to change, or to approve an already made 

 change in, the designation of the season or tetramene 

 in which the inundation commenced, from Thoth to 

 Pachons. 



Another function was to establish a fixed year, as we 

 shall see presently. We must assume then that a vague 

 year was in vogue prior to the decree. Now the decree 

 tells us that at its date the heliacal rising of Sirius took 

 place on i Payni. Assuming that this date had any re- 

 lation to the system we have been considering, the cycle 

 to which it belonged must have begun 



Days. 

 5 Epacts 

 30 Mesori 

 30 Epiphi 

 30 Payni 



95 X 4 



380 years previously ; that is, in the 

 year 618 B.C. 



Now here at first sight it would seem that the Sothic 

 cycles we have been considering have no relation to the 

 one now in question ; for, according to my view, the last 

 Sothic cycle began in 1728 B.C. 



A little consideration, however, will lead to the contrary 

 view, and show that the time about 600 B.C. was very 

 convenient for a revision of the calendar. 



In the first place nearly a month now elapsed between 

 the coming of the flood and the heliacal rising ; and in 

 the second, by making the year for the future to begin 

 with the flood, a change might be made involving tetra- 

 menes only. 



Thus, commencement of cycle ... 1728 B.C. 



Epacts 5 



Two tetramenes ... 240 



Month between flood and 

 rising of Sirius ... 30 ■■■ 



275 X 4 = 1 100 



628 B.C. 



Nor is this all. A very simple diagrammatic statement 

 will show what might also have happened about 618 B.C. 



is natural that the signs for the tetramenes should have changed their 

 significations in the course of millenniums. 



" While Thoth was the first month of the inundation in the documents of 

 the Thutmo.sids and Ramessids, we have in the time of the Ptolemies the month 

 Pachons as the first month of the flood season. Whilst Brugsch's explanation 

 is valid for the time of the Ramessids, it is not so for that of the Ptolemies, 

 to which Champollion's view is applicable." 



1 Probably too great a value-by 2 or 3 days. 



