days divided into twelve months of thirty days each; other documents of this period also testify that the lunar month
so Herodotus, History, Bk. ii. 4 (transl. A. D. Godley).
31 See volume of Manetho in Loeb Classical Library.
32 Georgii Monachi Chronographia (ed. P. Jacobi Goar, 1652), p. 123.
33 In the days of the Hyksos King Aseth. But see the Section "Changes in the Times and the Seasons.'
3* Translated by F. C. Babbit.
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had thirty days, and that a new moon was observed twelve times in a period of 360 days. The Sothis book says that this 360-day year was established under the Hyksos, who ruled after the end of the Middle Kingdom, preceding the Eighteenth Dynasty.
In the eighth or seventh century the five epigomena days were added to the year under conditions which caused them to be regarded as unpropitious.
Although the change in the number of days in the year was calculated soon after it occurred, nevertheless, for some time many nations retained a civil year of 360 days divided into twelve months of thirty days each.
Cleobulus, who was counted among the seven sages of ancient Greece, in his famous allegory represents the year as divided into twelve months of thirty days: the father is one, the sons are twelve, and each of them has thirty daughters.35
From the days of Thales, another of the seven sages, who could predict an eclipse, the Hellenes knew that the year consists of 365 days; Thales was regarded by them as the man who discovered the number of days in the year. As he was born in the seventh century, it is not impossible that he was one of the first among the Greeks to learn the new length of the year; it was in the beginning of that century that the year achieved its present length. A contemporary of Thales and also one of the seven sages, Solon was regarded as the first among the Greeks to find that a lunar month is less than thirty days.36 Despite their knowledge of the correct measure of the year and the month, the Greeks, after Solon and Thales, continued to keep to the obsolete calendar, a fact for which we have the testimony of Hippocrates ("Seven years contain 360
weeks"), Xenophon, Aristotle, and Pliny.37 The persistence of reckoning by 360 days is accounted for not only by a certain reverence for the earlier astronomical year, but also by its convenience for every computation.
robin-bobin
35 See Diogenes Laertius, Lives of Eminent Philosophers, "Life of Thales."
36 Proclus, The Commentaries on the Timaeus of Plato (1820); Diogenes Laertius, Lives, "Life of Solon"; Plutarch, Lives, "Life of Solon."
37 Aristotle Historia animalium vi. 20; Pliny, Natural History, xxxiv. 12 (transL Bostock and Riley).
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The ancient Romans also reckoned 360 days to the year. Plutarch wrote in his "Life of Numa"
that in the time of Romulus, in the eighth century, the Romans had a year of 360 days only.88
Various Latin authors say that the ancient month was composed of thirty days.39
On the other side of the ocean, the Mayan year consisted of 360 days; later five days were added, and the year was then a tun (360-day period) and five days; every fourth year another day was added to the year. "They did reckon them apart, and called them the days of nothing: during the which the people did not anything," wrote J. de Acosta, an early writer on America.40
Friar Diego de Landa, in his Yucatan before and after the Conquest, wrote: "They had their perfect year like ours, of 365 days and six hours, which they divided into months in two ways. In the first the months were of 30 days and were called U which signifies the moon, and they counted from the rising of the new moon until it disappeared."41 The other method of reckoning, by months of twenty days' duration (uinal hunekeh), reflects a much older system, to which I shall return when I examine more archaic systems than that of the 360-day year. De Landa also wrote that the five supplementary days were regarded as "sinister and unlucky." They were called "days without name."42 Although the Mexicans at the time of the conquest called a thirty-day period "a moon," they knew that the synodical moon period is 29.5209 days,43 which is more exact than the Gregorian calendar introduced in Europe ninety years after the discovery of America. Obviously, they adhered to an old tradition dating from the time when the year had twelve months of thirty days each, 360 days in all.44
38 Plutarch. Lives, "The Life of Numa," xviii.
39 Cf. Geminus Elementa astronomiae viii; cf. also Cleomedes De motu circulari corporum celestium xi. 4.
40 J. de Acosta, The Natural and Moral Histories of the Indies, 1880 (Historia natural y moral de las Indias, Seville, 1590).
41 Diego de Landa, Yucatan, p. 59.
<2 D. G. Brinton, The Maya Chronicles (1882).
43 Gates' note to De Landa, Yucatan, p. 59.
44 R. C. E. Long, "Chronology—Maya," Encyclopaedia Britannica (14th ed.): 340 WORLDS IN COLLISION
In ancient South America also the year consisted of 360 days, divided into twelve months.
"The Peruvian year was divided into twelve Quilla, or moons of thirty days. Five days were added at the end, called Allcacanquis." 45 Thereafter, a day was added every four years to keep the calendar correct.
We cross the Pacific Ocean and return to Asia. The calendar of the peoples of China had a year of 360 days divided into twelve months of thirty days each.46
A relic of the system of 360 days is the still persisting division of the sphere into 360 degrees; each degree represented the diurnal advance of the earth on its orbit, or that portion of the zodiac which was passed over from one night to the next. After 360 changes the stellar sky returned to the same position for the observer on the earth.
When the year changed from 360 to 365M days, the Chinese added five and a quarter days to their year, calling this additional period Khe-ying; they also began to divide a sphere into 365K
degrees, adopting the new year-length not only in the calendar, but also in celestial and terrestrial geometry.47
Ancient Chinese time reckoning was based on a coefficient of sixty; so also in India, Mexico, and Chaldea, sixty being the universal coefficient.
The division of the year into 360 days was honored in many ways,48
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"They [the Mayas] never used a year of 365 days in counting the distance of time from one date to another."
45 Markham, The Incas of Peru, p. 117.
48 Joseph Scaliger, Opus de emendatione temporum, p. 225; W. Hales, New
Analysis of Chronology (1809-1812), I, 31; W. H. Medhurst, notes to pp. 405-406 of his translation of The Shoo King (Shanghai, 1846).
47 H. Murray, J. Crawfurd, and others, An Historical and Descriptive Account of China (p. 235); The Chinese Classics, III, Pt. 2, ed. Legge (Shanghai, 1865), note to p. 21.
Cf. also Cantor, Vorlesungen, p. 92: "Zuerst wurde von den Astronomen Babylons das Jahr von 360 Tagen erkannt, und die Kreisteilung in 360 Grade sollte den Weg versinnlichen welchen die Sonne bei ihrem vermeintlichen Um-laufe urn die Erde jeden Tag zuriicklegte."
48 C. F. Dupuis (L'Origine de tous les cultes [1835-1836], the English compendium being The Origin of All Religious Worship [1872], p. 41) gathered material on the number 360, "which is that of the days of the year without the
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and, indeed, it became an incentive to progress in astronomy and geometry, so that people did not readily discard this method of reckoning when it became obsolete. They retained their
"moons" of thirty days, though the lunar month in fact became shorter, and they regarded the five days as not belonging to the year.
All over the world we find that there was at some time the same calendar of 360 days, and that at some later date, about the seventh century before the present era, five days were added at the end of the year, as "days over the year," or "days of nothing."