{"id":12982,"date":"2014-05-01T20:14:19","date_gmt":"2014-05-01T19:14:19","guid":{"rendered":"http:\/\/www.roger-pearse.com\/weblog\/?p=12982"},"modified":"2014-05-01T20:14:19","modified_gmt":"2014-05-01T19:14:19","slug":"caesars-reform-of-the-calendar-some-ancient-sources","status":"publish","type":"post","link":"https:\/\/roger-pearse.com\/weblog\/2014\/05\/01\/caesars-reform-of-the-calendar-some-ancient-sources\/","title":{"rendered":"Caesar’s reform of the calendar – some ancient sources"},"content":{"rendered":"

Plutarch,\u00a0Caesar<\/em><\/a> 59:<\/p>\n

\n

59. 1. The adjustment of the calendar, however, and the correction of the irregularity in the computation of time, were not only studied scientifically by him, but also brought to completion, and proved to be of the highest utility.<\/p>\n

2.\u00a0For not only in very ancient times was the relation of the lunar to the solar year in great confusion among the Romans, so that the sacrificial feasts and festivals, diverging gradually, at last fell in opposite seasons of the year,\u00a03.\u00a0but also at this time people generally had no way of computing the actual solar year;\u00a0the priests alone knew the proper time, and would suddenly and to everybody’s surprise insert the intercalary month called Mercedonius.<\/p>\n

4.\u00a0Numa the king is said to have been the first to intercalate this month, thus devising a slight and short-lived remedy for the error in regard to the sidereal and solar cycles, as I\u00a0have told in his Life.<\/p>\n

5.\u00a0But Caesar laid the problem before the best philosophers and mathematicians, and out of the methods of correction which were already at hand compounded one of his own which was more accurate than any. This the Romans use down to the present time, and are thought to be less in error than other peoples as regards the inequality between the lunar and solar years.<\/p>\n

6.\u00a0However, even this furnished occasion for blame to those who envied Caesar and disliked his power. At any rate, Cicero the orator, we are told, when some one remarked that Lyra would rise on the morrow, said: “Yes, by decree,” implying that men were compelled to accept even this dispensation.<\/p>\n<\/blockquote>\n

Macrobius,\u00a0Saturnalia<\/em>, bk 1, ch. 14:[ref]Translated by Percival Vaughan Davies, Columbia University Press, 1969.[\/ref]<\/p>\n

\n

2.\u00a0Subsequently, however, since there was thus inconsistency\u00a0in the marking of the times and seasons but all was still vague and\u00a0uncertain, Gaius Caesar introduced a clearly defined arrangement\u00a0of the calendar, with the help of a clerk named Marcus Flavius,\u00a0who provided the dictator with a list of the several days so arranged\u00a0that their order could be easily found and, that order once found,\u00a0the position of each day would remain constant.<\/p>\n

3.\u00a0Caesar therefore\u00a0began the new arrangement of the calendar by using up all the\u00a0days which could still have caused confusion, with the result that\u00a0the last of the years of uncertainty was prolonged to one of four\u00a0hundred and forty-three days. Then, copying the Egyptians – the\u00a0only people who fully understood the principles of astronomy – he\u00a0endeavored to arrange the year to conform to the duration of\u00a0the course of the sun, which it takes three hundred and sixty-five\u00a0days and a quarter to complete.<\/p>\n

4.\u00a0For just as the lunar cycle is\u00a0the month, since the moon takes rather less than a month to make\u00a0a circuit of the zodiac, so the solar cycle must be reckoned by the\u00a0number of days which the sun takes to turn again to that sign of\u00a0the zodiac from which it began its course. That is why the common\u00a0year is styled the “turning” year and is held to be the “great”\u00a0year (since the lunar cycle is thought of as the “short” year), \u00a05.\u00a0and Vergil has combined these two descriptions of the solar year\u00a0in the line:<\/p>\n

Meanwhile the sun completes the turning of the great year.\u00a0[Aeneid 3. 284]<\/p>\n

It is for this reason that Ateius Capito too thinks that the word\u00a0“year” (annus<\/em>) is to be explained as a circuit of time; namely,\u00a0because of old an used to stand for “around,” as, for example,\u00a0where Cato in his Origins<\/em> writes: “Let the plough be driven around\u00a0the boundary,” using an<\/em> instead of circum<\/em>; or when we say ambire<\/em>
\nfor circumire<\/em>.<\/p>\n

6. Julius Caesar therefore added ten days to the old arrangement\u00a0of the calendar, in order that the year might consist of the\u00a0three hundred and sixty-five days which the sun takes to pass\u00a0through the zodiac; and, to allow for the remaining quarter of a\u00a0day, he ordained that the priest in charge of the months and days\u00a0should insert one day every fourth year in that month, and in that\u00a0part of it, in which of old an intercalary month used to be inserted,\u00a0that is to say, immediately before the last five days of February.\u00a0This intercalary day he ordered to be called bissextus<\/em> [as doubling\u00a0the sixth day before the Kalends of March].<\/p>\n

7. The arrangement\u00a0to distribute the ten additional days to which I have referred was\u00a0as follows: January, Sextilis, and December received two days each,\u00a0and April, June, September, and November one each. No addition\u00a0was made to the month of February, lest changes in connection\u00a0with the worship of the gods below might result; and March, May,\u00a0Quintilis, and October remained as they had been of old, because\u00a0they already had the full complement of thirty-one days apiece.<\/p>\n

8. And, since Caesar made no change in these four months, they\u00a0also have the Nones on the seventh day, as laid down by Numa.\u00a0But in January, Sextilis, and December, the months to which Caesar\u00a0added two days apiece, although after his reforms each for the\u00a0first time had thirty-one days, nevertheless the Nones come on the\u00a0fifth day and the Kalends that follow return on the nineteenth day\u00a0after the Ides, because Caesar would not insert the additional days\u00a0before either the Nones or the Ides for fear that an unprecedented\u00a0postponement by two days (which would be the result of such\u00a0change) might interfere with religious ceremonies appointed to be\u00a0held on a day fixed in relation to the Nones or Ides.<\/p>\n

9.\u00a0Nor yet\u00a0would he insert the additional days immediately after the Ides for\u00a0fear of disturbing appointed rest days, but a place was not made for\u00a0them in any month until the celebration of the rest days held in that
\nmonth had been completed. Thus in January the allotted days to\u00a0which we refer were the fourth and third days before the Kalends\u00a0of February; in April, the sixth day before the Kalends of May; in\u00a0June, the third day before the Kalends of July; in August, the\u00a0fourth and third day before the Kalends of September; in September,\u00a0the third day before the Kalends of October; in November,\u00a0the third day before the Kalends of December; and in December,\u00a0the fourth and third days before the Kalends of January.<\/p>\n

10.\u00a0Consequently, although, before this reform, in all the months to\u00a0which days were added the Kalends of the following months returned\u00a0on the seventeenth day after the Ides; afterward, as the\u00a0result of the additions, the Kalends returned on the nineteenth day\u00a0after the Ides in the months which received two days and on the\u00a0eighteenth in the months which received one.<\/p>\n

11. In each month,\u00a0however, rest days kept their appointed places. For example, if the\u00a0third day after the Ides was generally observed as a festival or a\u00a0rest day and used formerly to be known as the sixteenth day before\u00a0the following Kalends, even after the number of days in the month\u00a0had been increased, the religious observance remained unchanged\u00a0and the ceremony was still held on the third day after the Ides, although\u00a0(in consequence of an increase in the number of days in the\u00a0month) the day was no longer the sixteenth day before the following\u00a0Kalends but the seventeenth, if one day had been added to the\u00a0month, and the eighteenth, if two days had been added.<\/p>\n

12.\u00a0That\u00a0is why Caesar inserted the new days, in each case, toward the end\u00a0of the month, at a time when all the rest days in the month were\u00a0found to be over. Moreover, he caused these additional days to be\u00a0marked in the calendar as fasti<\/em>, so as to make more time available\u00a0for legal business; and he not only arranged that all these days\u00a0should be such days of legal business but also that none should be\u00a0a day on which an assembly might be held, his intention being that\u00a0this increase in the number of the days should not add to a\u00a0magistrate’s power to exercise undue influence.<\/p>\n

13. Caesar’s regulation of the civil year to accord with this\u00a0revised measurement was proclaimed publicly by edict, and the\u00a0arrangement might have continued to stand had not the correction\u00a0itself of the calendar led the priests to introduce a new error of\u00a0their own; for they proceeded to insert the intercalary day, which\u00a0represented the four quarter-days, at the beginning of each fourth\u00a0year instead of at its end, although the intercalation ought to have\u00a0been made at the end of each fourth year and before the beginning\u00a0of the fifth.<\/p>\n

14. This error continued for thirty-six years, by\u00a0which time twelve intercalary days had been inserted instead of the\u00a0number actually due, namely, nine. But, when this error was at\u00a0length recognized, it too was corrected, by an order of Augustus\u00a0that twelve years should be allowed to pass without an intercalary\u00a0day, since a sequence of twelve such years would account for those\u00a0three days too many which, in the course of the thirty-six years,\u00a0had been introduced by the premature action of the priests.<\/p>\n

15.\u00a0After that, one intercalary day, as ordered by Caesar, was to be\u00a0inserted at the beginning of every fifth year, and the whole of this\u00a0arrangement of the calendar was to be engraved on a bronze tablet,\u00a0to ensure that it should always be observed.<\/p>\n<\/blockquote>\n

Pliny the Elder,\u00a0Natural History<\/em>, bk. 18:<\/p>\n

\n

56. \u00a0There follows the question postponed to this\u00a0place, a question that needs very careful consideration\u00a0– that of the proper date for sowing the crops; it is\u00a0in a large degree connected with astronomy, and\u00a0consequently we will begin by setting out the views\u00a0of all authors in regard to it. …<\/p>\n

57. First of all it is almost impossible to explain the system of the actual days of the year and that\u00a0of the movement of the sun, because to the 365\u00a0days an intercalary year adds a quarter of a day\u00a0and of a night, and consequently definite periods of\u00a0the stars cannot be stated. In addition to this\u00a0there is the admitted obscurity of the facts, as\u00a0sometimes the specification of the seasons runs in\u00a0advance, and by a considerable number of days …\u00a0, whereas at\u00a0other times it comesbehind …\u00a0and in general the influence of the heavens falls\u00a0down to the earth in one place more quickly and\u00a0in another place more slowly; this is the cause of\u00a0the remark we commonly hear on the return of\u00a0fine weather, that a constellation has been completed. \u00a0Moreover although all these things depend\u00a0on stars that are stationary and fixed in the sky,\u00a0there intervene movements of stars and hailstorms\u00a0and rain, these also having no inconsiderable effect,\u00a0as we have shown, and they disturb the regularity of the expectation that has been conceived. …<\/p>\n

Additional difficulty\u00a0has also been caused by authors through their observations\u00a0having been taken in different regions, and\u00a0because in the next place they actually publish\u00a0different results of observations made in the same\u00a0regions. But there were three main schools, the\u00a0Chaldaean, the Egyptian and the Greek; and to\u00a0these a fourth system was added in our own country\u00a0by Caesar during his dictatorship, who with the assistance\u00a0of the learned astronomer Sosigenes brought\u00a0the separate years back into conformity with the\u00a0course of the sun – and this theory itself was afterwards\u00a0corrected (when an error a had been found), so\u00a0as to dispense with an intercalary day for a period\u00a0of twelve successive years, for the reason that the\u00a0year which had previously been getting in advance\u00a0of the constellations had begun to lag behind in\u00a0relation to them.<\/p>\n

Both Sosigenes himself in his\u00a0three treatises – though more careful in research\u00a0than the other writers he nevertheless did not hesitate\u00a0to introduce an element of doubt by correcting\u00a0his own statements – and also other authors whose\u00a0names we prefixed to this volume have published\u00a0these theories, although it is\u00a0seldom that the opinions\u00a0of any two of them agree.<\/p>\n

… the\u00a0morning setting of the Pleiads is given by Hesiod\u00a0– for there is extant an astronomical work that\u00a0bears his name also – as taking place at the close\u00a0of the autumnal eqninox, whereas Thales puts it\u00a0on the 5th day after the equinox, Anaximander on\u00a0the 30th, Euctemon on the 44th, and Eudoxus\u00a0on the 48th. \u00a0 We follow the observation of Caesar\u00a0specially: this will be\u00a0the formula for Italy; but we\u00a0will also state the views of others, …<\/p>\n

70. \u00a0From midwinter till the west wind blows\u00a0the important stars that mark the dates, according to\u00a0Caesar’s observations, are\u00a0– the Dogstar setting at\u00a0dawn on December 30, the day on which the Eagle is\u00a0reported to set in the evening for Attica and the neighbouring\u00a0regions; on January 4 according to Caesar’s\u00a0observations the Dolphin rises at dawn and the next\u00a0day the Lyre, the Arrow setting in the evening on the same day for Egypt …<\/p>\n

75.\u00a0Between the period of west wind and the\u00a0spring equinox, February 16 for Caesar marks three\u00a0days of changeable weather, as also does February\u00a022 by the appearance of the swallow and on\u00a0the next\u00a0day the rising of Arcturus in the evening, and the\u00a0same on March 5 – Caesar noticed that this bad\u00a0weather took place at the rising of the Crab, but the\u00a0majority of the authorities put it at the setting of\u00a0the Vintager – on March 8 at the rising of the\u00a0northern part of the Fish, and on the next day\u00a0at the rising of Orion; in Attica it is noticed that\u00a0the constellation Kite appears. Caesar also noted\u00a0March 15 – the day that was fatal to him – as\u00a0marked by the setting of the Scorpion, but stated\u00a0that on March 18 the Kite becomes visible in\u00a0Italy and on March 21 the Horse sets in the\u00a0morning. \u00a0…<\/p>\n<\/blockquote>\n

I’ve added a little more from Pliny than strictly necessary, as it indicates that Caesar’s calendar was not merely what we think of as the Julian calendar, but comprised a whole series of astronomical notations, for the purpose of crop management. \u00a0No doubt Sosigenes compiled these, but it is interesting to see them.<\/p>\n","protected":false},"excerpt":{"rendered":"

Plutarch,\u00a0Caesar 59: 59. 1. The adjustment of the calendar, however, and the correction of the irregularity in the computation of time, were not only studied scientifically by him, but also brought to completion, and proved to be of the highest utility. 2.\u00a0For not only in very ancient times was the relation of the lunar to […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_hide_featured_image":false,"_jetpack_featured_image_duplicate_dismissed":0,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[19],"tags":[962,1058,1349,1352,1448,1556],"class_list":["post-12982","post","type-post","status-publish","format-standard","hentry","category-from-my-diary-announcements","tag-julius-caesar","tag-macrobius","tag-pliny-the-elder","tag-plutarch","tag-roman-time","tag-sosigenes"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/posts\/12982","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/comments?post=12982"}],"version-history":[{"count":0,"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/posts\/12982\/revisions"}],"wp:attachment":[{"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/media?parent=12982"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/categories?post=12982"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/roger-pearse.com\/weblog\/wp-json\/wp\/v2\/tags?post=12982"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}