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KRONOS Vol. I, Issue 2
Limitations of Astronomical Dating Methods*
|Censorinus dates himself||Accepted date||Calculated date for Censorinus|
|1040 years from the Olympiad era||776||B.C. 264 A.D.|
|896 years from the founding of Rome||753||B.C. 143 A.D.|
|283 years from Parilibus|
|986 years from Nabonassar's era||746||B.C. 240 A.D.|
|562 years from Philippi||357||B.C. 205 A.D.|
|265 years from Augustus||28||B.C. 237 A.D.|
The statement of Censorinus is commonly regarded as corroborated by the statement of Theon, an ancient astronomer of Alexandria, who said that 1605 years had elapsed between the era of king Menophres and the era of Diocletian.(20) The era of Diocletian is rather firmly fixed as beginning in 284 A.D. This provides the date 1321 for Menophres, which date coincides satisfactorily with the date 1320 for the beginning of a Sothic period as calculated from the interpretation of Censorinus, which places his writing in 240 A.D. and the beginning of a Sothic period in 140 A.D. As one becomes aware of the degree of confusion which existed among the ancient writers relative to their own past, it would seem almost certain that Theon did not possess information which would permit him to place the date 1320 B.C. in the reign of any particular king with certainty. We have here then only a situation where two statements, each uncertain in its interpretation and in its validity, provide a questionable corroboration of each other.
It would seem strange, if astronomers are able to calculate backward in time and date eclipses centuries before Christ, that they would not be able to calculate back and determine whether or not the star, Sirius, was on the horizon at sunrise in Egypt on the Egyptian New Year's Day in the year 140 A.D. Actually, this calculation has been made, but one sees these data quoted with apparent reticence. The calculation was made by the astronomer Poole over one hundred years ago and was corroborated for correctness by the Astronomer Royal of London.(21) The calculations show that Sirius was not on the horizon coincident with the rising sun on this day. It was 1 hour and 16 minutes above the horizon at Thebes and slightly less than this at Memphis.* We are thus faced with a curious anomaly. What shall we conclude? Are we to presume that the astronomers did not know how to make these calculations? Shall we conclude that Censorinus did not know that of which he spoke so glibly, or that his calculations were in error or possibly based on the same erroneous data used by Theon? Or is it possible that the statement of Theon is being mis-interpreted? Is it possible that it was not Sirius which is the star to be identified as Sothis? Or shall we conclude that the beginning of the Sothic period was marked by a position of Siruis which was 1 hour and 16 minutes above the horizon at sunrise? Is it possible that historians have misdated Censorinus? Or is there a possibility that Censorinus is quite correct in his dating, but that historians are mistaken about the significance of this period and in the manner in which it was used by the ancients?
[Note: *To avoid the discrepancy as it exists for either Thebes in southern Egypt or Memphis in northern Egypt, the geographic location for the origin of the observation leading to this definition of a Sothic rising has been moved still further north to Alexandria. Since the discrepancy decreases as one moves northward, this ameliorates the difficulty somewhat However, the rising of Sothis must still be defined as an appearance of the star Sirius about the time of sunrise. There is considerable doubt that Alexandria can be regarded as the site of the original observations in 1320 B.C.]
The obvious conclusion is that there is something radically wrong with the reasoning and the calculations which have led to the placement of the Sothic cycle beginning in 140 A.D. This point alone may be regarded as sufficient basis for a disagreement among the authorities as to the date to be assigned to the beginning of this period and for the difference of opinion as to the reliance which should be placed on the use of this period for dating purposes. The historian Budge wrote in a most skeptical manner on this point: (22)
. . . It must be remembered that, as said above, very little reliance is to be placed on any calculations of this kind in attempting to formulate an exact chronology, especially as authorities, both ancient and modern, are not agreed as to the exact date in the second century of our era when the Sothic period ended on which they based their calculations.
Actually the extent of the disagreement in the matter of the date for the beginning of a Sothic period is not limited to an exact fixing of this date in the second century of our era. The astronomer Lockyer fixed the date for the beginning of the cycle in the year 269 B.C., some 409 years earlier than that deduced by historians from Censorinus. Lockyer built up a chronology of the XVIIIth and other dynasties with dates set some 400 years earlier than the ones now so familiar for these dynasties based on Censorinus. MacNaughton set up a chronology based on the supposition that Sothis was not Sirius, but Spica, as a way around the difficulty, (23)
The question might be raised as to what happens if one of the alternate dates is taken for Censorinus and the beginning of the Sothic period is adjusted to this date. The answer is simple but disastrous. For if we do not take the statement of Censorinus as is traditionally done, then the statement of Theon does not corroborate Censorinus, and we have a shaky basis indeed for the entire concept of Sothic dating. The same holds true if we try to adjust this date to that when Sirius was actually on the horizon at sunrise on the Egyptian New Year's Day. There would seem to be little by way of alternative. We must either accept this traditional interpretation of Censorinus in spite of the anomalies involved or admit that some gross errors have been made in the presumed fixation of the dates for the XIIth and XVIIIth Egyptian Dynasties.
Calculations Based on the Sothic Theory Are Invalid
Since Meyer first outlined his theories which form the bases of astronomical dating by the Sothic method, astronomers have had occasion to scrutinize the reasoning leading to Meyer's conclusions and have not been highly impressed. The Sothic theory as proposed by Meyer presumes that the Egyptians had determined by observation the length of the Sothic period and had used it subsequently as a long range calendar. This conclusion now seems to be quite out of the question. The trouble lies in part in the fact that the true solar year is not exactly 365 1/4 days, but is some 12 minutes short of this. A simple calculation, using the correct year length, shows that the true Sothic period is not 1460 years in length but 1507 years long.(24) The astronomers point out that during this time, the sun itself will move among the stars, and this motion is in a direction such as to partly offset the discrepancy between 1460 and 1507 years. The remaining discrepancy may be considered as sufficiently small so that the Egyptians would not detect the difference in a single Sothic period since four solar years are required for the vague year to deviate by a single day. However, the difference would certainly be apparent on the second Sothic rising and would represent an embarrassing amount of error by the third one. Since it had been assumed that the whole concept was adopted by the Egyptians as a result of observations,(25) it becomes apparent that any calendar thus set up in 4240 B.C. would be obsolete by 1322 B.C., two Sothic periods later. Since we have no reference from antiquity giving the beginning of any period prior to 1322 (assuming that Theon is referring to such), we are confronted with a presumed calendar already obsolete at the time of the first suggestion of such a beginning. It is thus quite out of the question that the Sothic period was used in the way presumed by Meyer, and his supposed date for the introduction of a calendar based on the Sothic cycle remains hanging in mid-air without a shadow of foundation.
The Egyptian Calendar Has Not Been Fixed Throughout the Period During Which Sothic Dating Methods Are Employed
The utilization of Sothic data for historical dating must presume that there was no change in the calendar of Egypt during the period to which the method is applied. Even after the disposition of Meyer's theory relative to the introduction of a Sothic calendar in 4240 B.C., the use of the method must still presume that no alterations in the calendar occurred between the XIIth Dynasty and the time of Censorinus which involved the length of the calendar year or the position of the months in the year. A single such alteration in this interim would invalidate all calculations and conclusions from this dating method for periods prior to such change. Actually there are a number of evidences that indicate changes in the Egyptian calendar after the time of the XIIth Dynasty.
A note appended to the name of King Aseth, one of the late Hyksos kings, whose name appears in the Sothis king list, reads: (26)
This king added the 5 intercalary days to the year: in his reign, they say, the Egyptian year became a year of 365 days, being previously reckoned as 360 days only.
Another version of Manetho credits this same calendar alteration to the Hyksos king, Saites, at an earlier date.(27) These two records are not necessarily contradictory, since the two kings may have introduced the change in different parts of Egypt in the two cases. The question of the reliability of the note is pertinent. As previously noted, these inserted notes may represent opinions or calculations based on inadequate evidence, just as may be supposed for the calculation of Censorinus. The question of the reliability of this note must be decided on its own merits.
It has been suggested that the note has no significance, since it is otherwise known that the 365 day year was in use back as far as the Vth Dynasty. But this is no evidence against the authenticity or reliability of the note, for the calendar could have been changed from 365 days to 360 days at the time the Hyksos took over Egypt and then returned to the 365 day year at the time of Aseth. Certainly it is not illogical to suppose that the Hyksos brought their own calendar with them when they took over the control of Egypt. Even if this 360 day calendar had a very short life, this would be sufficient to completely ruin the validity of any calculations based on a presumed fixed calendar. While the point in question may not be capable of proof or disproof at this time, the note must be considered as casting doubt on the validity of any chronology which is based on the assumption of a fixed calendar. In view of the anomalous chronology which has resulted from the application of the Sothic theory, it would seem that the simplest explanation lies in the probability of error in this assumption of an unaltered calendar in Egypt through the period from 2000 B.C. to 140 A.D.
There is also considerable evidence to indicate that the first month of the Egyptian calendar did not remain unaltered during this period. By the year 721 B.C., and probably as early as 851 B.C., the month Thoth was the first month of the Egyptian calendar.(28) From inscriptions dealing with New Year ceremonies of an earlier era, Brugsch deduced that the month Hathor was the first month of the year at this earlier period.(29) The Ebers papyrus definitely gives the month Menkhet as the first month of the year.(30) In the XXth Dynasty, Hathor is the 4th month and Mesorii is the first.(31)
The ease with which the calendar could be altered is indicated by the fact that both Amenhotep III and Rameses II altered the sequence of the so-called Sed Festivals. These rulers were dictators, and there is no reason to presume that if one of them decided to make New Year's Day coincide with his birthday, or for some other insignificant reason, elected to alter the calendar, he might not do so to meet his whims. In anticipation of the Julian calendar adopted many years later, Ptolemy III introduced a true solar calendar of 365 1/4 days (probably in the year 235 B.C.). While it is not possible to relate all these various calendars to each other or to the present calendar, it would seem futile to hope to set up a valid chronology of Egypt based on the assumption that the calendar was not altered during the period from the XIIth Dynasty to the 3rd century A.D.(32) With the numerous inconsistencies and anachronisms in the chronology to which we have been led, it would seem that some one should have guessed that the difficulty lies in the extreme improbability of this premise on which the Sothic dating method rests.
Ancient Inscriptions Used to Support the Sothic Theory are Vague
There are perhaps five principal ancient records which have been used in attempts to fix certain dates or events or eras in the Sothic period. Besides these, there are perhaps this many more which have an equal right to such consideration but which are commonly disregarded because they do not fit satisfactorily into the scheme which has resulted from the acceptance of the others. Not a single one of these references can be regarded as providing unequivocal dates.
The first example to be noted is the statement previously referred to from Theon, pointing to the year 1320 as the date for the era of Menophres and presumed to indicate that a Sothic period began in this year. As noted above, the use of this statement depends for confirmation on the selection of the date 240 A.D. chosen from several possible dates derivable from the data provided by Censorinus. There is considerable doubt that the statement of Theon can be depended upon as factual.(33) Disconcerting also is the fact that no king of Egypt is elsewhere known by the name Menophres,* and hence his identity remains uncertain. If we follow the recognized rules for transliterating Greek names back to Egyptian, we arrive at the Egyptian name Mennefer-re. There are two kings in Egypt who had names sufficiently close to this to merit such tentative identification. The first is a name transliterated as Menoffirre, belonging to a Hyksos king. But the Hyksos era is far out of line by the traditional chronology to allow placement of this king in the year 1320 B.C., the last of the Hyksos kings having ended his rule by 1580 B.C. Second vote should go to Menoffire Ai of the XIIIth Dynasty, but this king is even farther out of line with the year 1320 and hence likewise cannot be seriously considered. We might give a third vote to Merneptah of the XIXth Dynasty, though this name is hardly the equivalent of Menophres. He falls closer to the desired date, but is still some 70 years out of line.
[Note: *... i.e., for the era of 1320 B.C See I. Velikovsky, "Astronomy and Chronology," Pensee IV (Spring-Summer, 1973) pp 44-45 and 49 and reference #93 of this article. – the Ed.]
Petrie suggested an identity to Rameses I, since he carried an alternate name of Men-peh-re, a name which again is hardly the counterpart of Menophres, but which has a resemblance. Petrie's suggestion has been generally accepted, not because of any convincing evidence, but rather because Rameses I falls within the era for which it has seemed logically possible to synchronize Egyptian history with later synchronims retained. Certainly nothing but the demand of the theory would give such credence to this proposed identity. If the theory proves anything at all, it proves that the year 1322 B.C. should fall during the period of Hyksos domination.
Petrie attempted to date the reign of Mer-en-re, a king of the Vlth Dynasty, by the Sothic method, from an inscription by one of his officials named Una.(34) Una tells us in his inscriptions that he had been sent by the king to the quarry at Het-nub to secure large stones to be used in providing altars for religious offerings. After securing the stones, he floated them down the river on a barge to Memphis, arriving in the month Epiphi when, according to the inscription, there was no water over the sandbars. In spite of this difficulty, he succeeded in bringing the barge to shore and unloading his stone. Petrie concluded from this situation that the end of flood season in that era occurred in the month Epiphi. On the basis of the calculated shift of the end of the flood season from its normal position in the seasons, it was calculated that king Mer-en-re reigned about 3350 B.C. (or one Sothic period earlier by the long chronology), with an allowable error of perhaps a hundred years in either direction.
Budge recognized the insecure basis on which Petrie's calculation rested. He comments:(35)
What Una narrates may show that the month of Epiphi was considerably out of place in the year when he went to Het-nub, but the possibility of deducing any date for the reigning king from this circumstance is too remote to be seriously entertained for a moment.
The skepticism of Budge on Petrie's conclusion has been fully borne out by subsequent developments in the field of Egyptian chronology. In the course of the last several decades, there has been an increasing tendency to accept the conclusion of Scharff that Mena, the first king of Egypt, must be moved to a date in the era of c. 2800 B. C. This date is some 400 years later than the latest date deduced for Mer-en-re of Dynasty VI, a situation which is of course impossible. One might argue that Mer-en-re of Dynasty VI should then be moved one full Sothic Period later than his placement by the short chronology and date him in the era of 1900 B.C. But this is not permissible, since this period is already assigned to the XIIth Dynasty by the same method of Sothic reckoning. We have heard no suggestion, other than our own. that the VIth Dynasty should be made contemporary with the XIIth. Or it might be argued that Una's arrival at Memphis was at the beginning of the flood season, before the waters had risen to cover the sandbars. This hardly makes sense either, for then Una's trip up the river with his barge must be placed during the dry season, and this in turn puts his quarrying work in the hot summer season, when quarrying was deliberately avoided because of the difficulties involved. The obvious conclusion would be that this inscription, like all others used to the same end, provides no basis whatever for dating the reign of Mer-en-re.
The Egyptologist, Ebers, discovered a papyrus dated on the reverse side as of the 9th day of the 11th month in the 9th year of king Zeserkare.(36) Ebers identified Zeserkare a Amenhotep I of the XVIIIth Dynasty, a conclusion which was hotly contested for a period prior to its general acceptance, since other kings were also known by this same name.* The papyrus contains data in the form of a calendar of months, which has been used as the basis of Sothic reckoning for the dating of Amenhotep I. The data, however, raised difficulties, since the calendar specifically refers to the month of Menkhet as the first month of the year, rather than Thoth, which was certainly the first month a few centuries later. The explanations offered to account for this discrepancy have, to say the least, not been very credible, and a recognition of a need for a simpler explanation has been voiced.(37) By assuming that the calendar meant Thoth when it read Menkhet, a date was calculated for Amenhotep I in the 16th century as demanded by the traditional chronology.
[Note: *The name in the extant inscription is partially effaced leaving a question as to whether the name has been properly read. The reading as Zeserkare, throne name of Amenhotep I, was hotly contested when proposed and other readings have been suggested. The uncertainty of this reading leaves the inscription without value for dating.]
An inscription presumed to have been produced under Thutmose III states that a Sothic rising took place on the 28th day of the third month of the season of inundation (i.e., the 11th month of the year).(38) However, the inscription does not state the name of the king nor the year of his reign. It is ascribed to Thutmose III on the basis of the appearance of this name on another fragment presumed to be from the same inscription, but found at some distance from it. The astronomer Torr commented on the worthlessness of this inscription to prove anything, since the inscription may have been produced by any one of the successors of Thutmose III.
Perhaps the most important inscription on which Meyer based his calculations is presented by what are known as the Kahoun Papyrii. This series of papyrii inscriptions were discovered by Borchardt in 1899, one fragment of which contains a reference to a Sothic rising which stands as the key record for Meyer's Sothic theory. The record is addressed to a priest by the name of Pepihotep and is dated in the 7th year of the reign of Sesostris III of Dynasty XII. That part of the record of primary interest here reads.(39)
"You ought to know that the rising of Sothis takes place on the 16th of the 8th month. Announce it to the priests of the town of Sekem-Usertesen and of Anubis on the mountain and of Suchos . . . and have his letter filed in the temple record."
Assuming that the "rising of Sothis" of this inscription refers to the coincident rising of Sothis with the sun (although calculations do not support this concept for the marking of the beginning of a Sothic period in the time of Censorinus), and assuming that Sothis is the star now known as Sirius (which assumption is not corroborated by astronomical calculations for the Sothic beginning in 140 A.D.), and assuming that the calendar involved in this inscription was for a vague year of 365 days which was not altered between this time and the time of Censorinus (which assumption would seem certainly to be in error), and assuming that the 8th month of this calendar was the same as the 8th month of the calendar at the time of Censorinus (which assumption must certainly be in error), it is calculated that the 7th year of Sesostris III fell in the era 1876-1872 B.C. Since the internal chronology of the XIIth Dynasty has been established with some degree of certainty, the era for the dynasty is thus regarded as fixed in the era approximated by the dates 2000-1787 B.C. These dates, as an approximation, are rather universally accepted among historians as marking the limits of Dynasty XII.
The reliability of this conclusion is no greater than that of the assumptions on which it is based. The least that can be said is that there are no less than three other interpretations for this inscription which are reasonable. The first of these assumes that, since the calendar of Egypt was not fixed from the time of the XIIth Dynasty, all possibility of connecting the calendar of this inscription with that on which Censorinus based his statement is lost, and even if the Sothic period was utilized by the Egyptians in the manner presumed, there remains no basis for dating events by this method. The second explanation presumes that the Egyptians, even at this early date used a true solar calendar of 365 1/4 days.(40) By this thesis, the expression "You ought to know that the rising of Sothis takes place," does not mean that the priest should know this because of recorded observations over the past period of 1460 years, but rather that he should have known this because it occurred at this same time every year. The third interpretation would presume that the star, Sothis, is not Sirius, since this star was not on the horizon at sunrise in Egypt on New Year's Day in 140 A.D. This theory was adopted by MacNaughton, who built up a complicated astronomical basis for his chronology based on the identification of Sothis as Spica.(41)
The author of this work holds to the view that, whatever the interpretation of Sothic data which may eventually be substantiated as correct, there is, nevertheless, very good reason for believing that the Egyptians, as early as the early IVth Dynasty, used a true solar calendar of 365 1/4 days which could be regarded as fixed in the same sense that our present calendar is fixed, i.e., it was periodically corrected to take care of the accumulated discrepancies. Even if a second migrating calendar was simultaneously in use for certain purposes, the references are too vague to permit the use of such as a basis for establishing a chronology. This deduction should be apparent, since none of the premises on which this theory of dating rests can be regarded as having been established. The inescapable evidence that the Egyptians of the IVth Dynasty had a knowledge of mathematics and astronomy sufficient to calculate the exact length of the year is presented in a subsequent section of this chapter.(42)
When one sees the significance of these alternate possibilities for interpreting the inscription of the Kahoun papyrii, there is no particular difficulty in realizing that there were ample grounds for the rejection of the theory of Sothic dating by Brugsch and other astute authorities, who simply could not see in it any solid basis for providing a system of dating, and more specifically, as far back as the XIIth Dynasty. It would seem that historians in general who understand the full import of the objections raised to the validity of this theory must admit that it is not possible to date events by this method as far back as the time of Sesostris III. There are some, however, who believe that when data are used in conjunction with data relative to a second cycle, such as that of the moon, then it is possible to date events back this far with a degree of exactness and certainty. Hence the assumptions on which such a belief rests require critical scrutiny.
The principles at point are very simple. If an event can be pinned down in two independent cycles, the chronological conclusions rest on a more secure foundation than when a single cycle is used. However, it must be apparent that the use of a very short cycle, such as that of the moon, to confirm dates derived by use of a much longer cycle, such as the Sothic cycle, has some very large inherent weaknesses. The cycle of the moon will repeat itself so many times in the course of one Sothic cycle that any given lunar data can be made to fit satisfactorily into the Sothic period at a considerable number of points. Hence, unless the date for the incident involved is known approximately and with certainty from independent data, it is very possible that any proposed confirmation may be only wishful thinking. The most that could be expected of this method is the determination of the most logical date within a relatively narrow era which provides the best harmony between lunar and Sothic data. If this narrow era has not been established with certainty, the conclusions reached are quite worthless as confirmation of a chronology.
Sothic Dating Has led to an Incredible Chronology
Not the least of the reasons for rejecting the Sothic method of dating is that it led historians to adopt an incredible chronology of Egypt. If we accept the Sothic datings for the XVIIIth Dynasty as demanded by the identification of Menophres with Rameses I and accept the most questionable datings based on the Ebers papyrus, then the beginning of the XVIIIth Dynasty is fixed at a date which cannot be far removed from 1580 B.C.(43) By the same token, if we accept the dating of Sesostris III as calculated from Sothic data found in the Kahoun papyrii, the end of the XIIth Dynasty is fixed at a date not far removed from 1788 B.C.(44)* This leaves a period which cannot be in any considerable excess of 210 years from the end of Dynasty XII to the beginning of Dynasty XVIII. Into this brief period must be squeezed all the reigns of the kings of the XIIIth Dynasty prior to the Hyksos invasion (probably some 26 or more in number), followed by the total period of Hyksos domination and a brief period for the XVIIth Dynasty.
[* "To abandon 1786 8.C. as the year when Dyn. XII ended would be to cast adrift from our only firm anchor, a course that would have serious consequences for the history. not of Egypt alone, but of the entire Middle East." – A. H. Gardiner, Egypt of the Pharaohs p. 148 – The Ed.]
At the time of the proposal of the fixation of the chronologies of the XIIth Dynasties, there was strenuous objection to the resulting structure. Petrie pointed out that on the basis of the data then available, the only rational conclusion would involve the insertion of an extra, full Sothic period of 1460 years into this interim. The comments of Petrie on this question are of sufficient importance to reproduce them here in part: (45)
. . . The question in debate is in which cycle the XIIth Dynasty occurred; does it end at 1786 B.C. or 3246 B.C.? Or, as it is agreed the XVIIIth dynasty began in 1580, were there 206 or 1666 years between the XIIth and XVIIIth dynasties? The advocates of the short period claim that there are not enough monuments known to fill more than two centuries. Yet we have remains of at least seventeen kings of the XIIIth dynasty, and every year adds to their number, which on an average of 7 years each is 120 years. The Hyksos age is now fairly defined, and requires us to recognize at least ten important reigns, besides the probability of a large number more, and 150 years would be a low estimate for what is already well known. And at least 10 years must be allowed in the XVIIth dynasty. Thus 280 years is covered by reigns which are evident, while we ignore the probability that we only know yet the minor part of the rulers in this very dark and confused period. To compress this into two centuries seems impossible. The advocates of the longer period consider that the evidence of changes in the art, the language, and the burial customs show that much more than two centuries had passed, and that this fully balances the supposed scantiness of monuments as historical material.
Subsequent developments have shown that it is equally impossible to insert an extra Sothic period between Dynasties XII and XVIII as proposed by Petrie, since it is now apparent that the date of Mena must be moved to a date later than that which would result for the end of Dynasty XII. However, the increasing amount of data from this era, between Dynasties XII and XVIII, make it necessary to leave room, not only for the 17 kings known when Petrie wrote, but for not less than 26 such kings in Dynasty XIII prior to the Hyksos invasion.(46)
As a result of the disagreement among historians on this point, two theories were held by various authorities known as the long and the short chronologies for the Hyksos era. Petrie was the principal proponent of the long chronology. Many historians were not primarily chronology conscious, and the remainder of those who were (Breasted, Meyer, and Weill) leaned toward the short chronology. With the death of Petrie, and the loss of the principal supporter of the long chronology, the short chronology has become generally accepted along with the chronology of later Egypt which results from this 208 year squeeze. A summary of the diverse opinions held by various authorities at the time is provided by MacNaughton. He writes: (47)
Breasted, accepting Meyer's arguments, drew up an elaborate chronology based on the minimum lengths of reign of the kings and Dynasties as shown from the monuments. On reading his chronology one is left with the impression that he regards a minimum date as likely to be the correct probability.... It is therefore strange that so able a scholar as Breasted should have stumbled into the same type of pitfall. Nevertheless his chronological discussions are very valuable provided it is kept in mind that what he really is demonstrating are the minimal dates, not the probable dates.
Petrie, with a knowledge of the practical difficulties in the way of Meyer's theory, proposed an extra Sothic cycle between the Twelfth and Eighteenth Dynasties, but this, though ingenious, is untenable with Sirius as Sothis.... What Petrie emphasized, however, was the complete incompatibility of Meyer's theory with the archaeological evidence and the evidence of the King Lists.
But as the outstanding Egyptologists with a chronological bent . . . were three in favour of a form of "short" chronology and one in favour of a "long" chronology, it is perhaps not surprising that those who had not time to study the chronological problem for themselves gave their vote for the "short" chronology.
Budge, however, refused to accept the "short" chronology and later, Hall thought he would effect a compromise by choosing a date for the Twelfth Dynasty intermediate between that of Meyer and of Petrie. He regarded the changes in art between the Twelfth and Eighteenth Dynasties as unlikely to have occupied so short an interval as 200 years or so long an interval as 1600-1700, and he entirely abandoned the Sothiac cycle as a clue to the period elapsed.
Petrie has now also abandoned the Sothiac cycle and substituted a theory that the dates of the Twelfth Dynasty were quoted in terms of a seasonal calendar. On cultural grounds, more particularly basing his conclusions on the variations in the types of Hyksos scarabs recently discovered by him, he now estimates the interval at about 800 years.
Baikie, who has evidently made a special study of the artistic side of Egyptian life, thinks that arguments based on estimates of length of time for a change to have taken place in the arts of a nation are based on a slender foundation and that on cultural grounds a "long" chronology is just as likely to be right as a"short" chronology.
Weigall favours a short chronology but is evidently conscious that to a reader new to the subject the crushing of the Thirteenth, Fourteenth, Fifteenth, Sixteenth, and Seventeenth Dynasties into two or three hundred years will appear somewhat ridiculous. He therefore excuses himself by explaining that "of course the most important argument in favour of the arrangement is that the Thirteenth, Fourteenth, and Fifteenth Dynasties have got to be fitted into a period between the astronomically fixed date of the fall of the Twelfth Dynasty and the rise of the Seventeenth." As the Twelfth Dynasty is not astronomically fixed where he thinks it is the necessity for the squeezing of the evidence disappears.
My own view [MacNaughton's] based principally on astronomical evidence, calendrical evidence, the evidence of the King Lists, and synchronisms with Babylonia, is that the interval from the end of the Twelfth Dynasty to the beginning of the Eighteenth Dynasty was somewhat less than 1500 years.
It should be noted that the reason why Breasted set up his chronology in terms of minimal reigns of the kings of Dynasties XVIII and XIX was because he was forced to do so to squeeze these dynasties into the period in such a fashion as to retain certain synchronisms which had long been accepted. While MacNaughton is unquestionably correct in his criticism of Breasted in this interpretation of the monumental data, it must be recognized that there is little by way of alternative if the limitations imposed by the Sothic method are accepted. The important thing to keep in mind is that the acceptance of either the long or the short chronology based on the fixation of dates by the Sothic dating method leads us to an incredible structure. Petrie's long chronology provides an untenably long period between the two dynasties, as he himself must have eventually recognized. The short chronology forces us to squeeze this period into an incredibly short space.
With the acceptance of the short chronology by historians in general, the problem has become one of dividing this 208 year period between Dynasties XIII, XVII, and the Hyksos period in some sort of a credible manner. The tendency seems to be to allow about 10 years for Dynasty XVII and divide the remaining time between the kings of Dynasty XIII and the Hyksos period. Neither of these allottments is credible. Even granting but 26 kings of Dynasty XIII before the Hyksos conquest only provides an average of four years reign for each. Elsewhere, such a condition would be interpreted unequivocally as a period of chaos approaching anarchy with a rapid turn-over of rulers. Yet the archaeological evidence indicates that no such conditions prevailed during this period.(48) Some of these rulers must have had very normal periods of reign with time to erect imposing monuments with no indication of haste.
Nor is it any more credibly possible to squeeze the Hyksos period into a 100 year period now than it was when Petrie pointed out the impossible nature of such an arrangement. Manetho allows 250 (or 284) years for Dynasty XV alone, giving the length of reign for each of its kings. Following this was a less well defined period of Dynasty XVI which may well have involved a divided reign between two or several kings at one time. To squeeze these two dynasties into a period of 100 years has no resemblance to the interpretation of Manetho's dynasties otherwise. Miss Kenyon allowed 150 years for the Hyksos.(49) This is still insufficient for the era and reduces the period for Dynasty XIII to a still more incredible value.
Were it not for the pressure of the presumed fixation of dates by the Sothic dating method, no historian would presume such a short period for this era on the basis of data otherwise available.
Not All Data Relative to the Sothic Cycle Fit into Meyer's Theory
If the interpretations of Meyer are correct, then all of the data which may be brought to bear on this problem should fit satisfactorily into the Sothic theory. This is far from the case. As of the present moment, there are far more data pertinent to the question which do not fit into the theory than there are which do apparently fit. The record. of Theon as related to Menophres and his identification to Rameses I has already been introduced. The collapse of the earlier interpretations relative to Una have also been referred to. The historian Brugsch called attention to two references to Sothic risings which were studied in detail by the astronomer Lockyer.(50) On the basis of one of these, Lockyer concluded that a Sothic period began in the year 269-270 B.C., which conclusion is at variance with the statement of Censorinus by some 409 years. In the reign of Osorkon II of Dynasty XXII, there was an unusually high Nile, which resulted in a flood of the temple of Osiris.(51) The flood is dated as occurring on Tybi 12, which in the year 876 B.C. (ascribed to Osorkon II), was "extraordinarily early" as calculated by Petrie. King Pankhi I of the XXVth Dynasty examined the fortifications near Memphis and noted that "the water came up to the road below the walls, and that ships were moored there."(52) The date would coincide with our April, at which time the Nile was at low level. To by-pass this anomaly, it has been supposed that some sort of a system of dams had been used to retain the water at high level during the dry season.
While Theon is commonly credited with supporting the concept that a Sothic period began in 1321 B.C. in the era of Menophres, he also leaves a clear statement to the effect that a Sothic period began in the 5th year of the reign of Augustus (B.C. 26).(53)
. . . Now this period of 1460 years, commenced from a certain time, terminated in the fifth year of the reign of Augustus; so, from this last epoch, the Egyptians began all over again to find themselves every year one quarter of a day in advance.
Later in his discourse, Theon again reiterated this concept:
". . . we have said that the return of the coincidence of the year of Alexandria with that of Egypt occured five years after the beginning of the reign of Augustus."
Unless we are permitted to conclude that there was more than one way of defining the beginning of a Sothic period, it is difficult to see how these statements can be harmonized with an interpretation of Theon which places the beginning of such a period in 1321 B.C. If we allow that there is more than one way of defining what was meant by the beginning of a Sothic period, then none of these references to such can, with certainty, be used for chronological purposes, and in neither case can we resort to Theon as an authority as far as defining a date for the beginning of such a Sothic period.
The Egyptians of the IVth Dynasty Had the Know-how for Correcting Their Calendar to an Exact Solar Year
The Sothic theory of dating has as its fundamental basis the belief that the Egyptians of early antiquity were not adequately versed in the mathematics of astronomy to permit a knowledgeable correction of their calendar in order to prevent the seasons from becoming displaced in the year. The current views on the chronology of Egypt are tightly bound to certain vague inscriptions which have been interpreted to indicate such a migration of the seasons. While it remains true that, to date, no inscription has been found stating explicitly that any such correction was made, this is no proof that such correction was not made. It is not scientifically feasible to use what we do not know as a support for the validity of deductions that cannot stand on their own feet otherwise.
On the other hand, evidence has long been available to indicate that the Egyptians back as far as the IVth Dynasty did have the know-how and the necessary information for making such adjustments in their calendar. If they had such knowledge, it is only reasonable to assume that this knowledge was used to make these corrections. This evidence does not preclude per se the possibility that such knowledge was lost during the subsequent centuries; however it is highly improbable that once the correction system was in use the mechanics of the correction would be lost. The vagueness of the evidence used to support the hypothesis of an uncorrected calendar as the sole calendar of Egypt does not warrant the use of such an hypothesis for "fixing" the chronology of ancient Egypt. The data in question are capable of an alternate interpretation that does not require recognition of such a wandering calendar.
It is first to be noted that the Egyptian seasons were named as the Season of Sowing, the Season of Harvesting, and the Season of Inundation. It is most unlikely that these names would be retained through a period of 1460 years, making it necessary to refer to the actual Season of Inundation as the Season of Sowing. More credible is the assumption that a correction system had already been devised and adopted before the seasons were given these names.
Secondly, as pointed out by Davidson, (54) the various references to sowing, harvesting, and quarrying through the era of the first twelve dynasties, which also refer to the month of the year, indicate that there is no necessity for supposing a shift of the seasons in the calendar year of months. It is true that such data can be made to fit into more than a single calendrical interpretation; hence undue weight should not be attached to such data. Nevertheless, any credible chronology should be able to show a reasonable degree of harmony with such references.
It is to be noted also that early Scripture refers to the year as composed of 12 months of 30 days each,(55) with no indication of any correction even to the extent of adding 5 intercalary days. Yet without such correction, the seasons would have migrated backward through the year at the rate of 5 1/4 days per year to give a cycle of only 70 years rather than 1460 years. The existence of such a situation is even more incredible than would have been the case in Egypt.
Other evidence from Scripture indicates that the calendar must have been corrected in spite of the absence of reference to such correction. This follows from the fact that the various feasts of the ancient Hebrews were related to both the seasons and to the calendar months. For example:(56)
Also in the fifteenth day of the seventh month, when ye have gathered in the fruit of the land, ye shall keep a feast unto the Lord....
The context indicates clearly that this was to be an annual festival; yet if the seasons had been migrating through the year, it would have required hardly a decade before the harvest would not have been in the seventh month at all. We do not know just how this correction was made in early Biblical times; we do know how it was done in post-Biblical times,(57) and the very fact that the Jews this late did correct their calendar to maintain a proper relation between feast days and the seasons reflects such a practice at least from the time of Moses.
REFERENCES1. D. MacNaughton, A Scheme of Egyptian Chronology (London, 1932), p. L The use of references from this work should not be taken to infer acceptance of MacNaughton's chronological scheme or of any of his interpretations of data used to support his scheme. However, he has accumulated a mass of factual data, not otherwise conveniently available and which are pertinent to the problems of ancient chronology. §AIso see E. J. Bickerman, Chronology of the Ancient World (Ithaca, 1969), p. 96, n. 1. – the Ed.