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Subject:
From:
Becky Taylor <[log in to unmask]>
Reply To:
St. John's University Cerebral Palsy List
Date:
Fri, 28 Jan 2000 10:49:55 -0800
Content-Type:
text/plain
Parts/Attachments:
text/plain (167 lines)
No, that doesn't start until next year.

At 09:21 AM 01/28/2000 -0500, you wrote:
>this is all very interesting. who know if we are in a new melinium or
>not?!!!
>
>-----Original Message-----
>From: Trisha Cummings [mailto:[log in to unmask]]
>Sent: Friday, January 28, 2000 9:04 AM
>To: [log in to unmask]
>Subject: January Notes - The History of the calendar
>
>
>Good Morning All,
>
>               Well, with this years calendars now going on sale!! I thought
>I would share a brief history about calendars.
>
>                                          Brightest Blessings
>                                                Trisha
>
>History of the Calendar
>
>The purpose of a calendar is to reckon time in advance, to show how many
>days have to elapse until a certain event takes place-the harvest, a
>religious festival, or whatever. The earliest calendars, naturally, were
>crude, and they must have been strongly influenced by the geographical
>location of the people who made them. In the Scandinavian countries, for
>example, where the seasons are pronounced, the concept of the year was
>determined by the seasons, specifically by the end of winter. The Norsemen,
>before becoming Christians, are said to have had a calendar consisting of 10
>months of 30 days each.
>
>But in warmer countries, where the seasons are less pronounced, the Moon
>became the basic unit for time reckoning; an old Jewish book actually makes
>the statement that "the Moon was created for the counting of the days." All
>the oldest calendars for which we have reliable information were lunar
>calendars, based on the time interval from one new moon to the next-a
>so-called lunation. But even in a warm climate there are annual events that
>pay no attention to the phases of the Moon. In some areas it was a rainy
>season; in Egypt it was the annual flooding of the Nile. It was, therefore,
>necessary to regulate daily life and religious festivals by lunations, but
>to take care of the annual event in some other manner.
>
>The calendar of the Assyrians was based on the phases of the Moon. The month
>began with the first appearance of the lunar crescent, and since this can
>best be observed in the evening, the day began with sunset. They knew that a
>lunation was 291/2 days long, so their lunar year had a duration of 354
>days, falling 11 days short of the solar year.1 After three years such a
>lunar calendar would be off by 33 days, or more than one lunation. We know
>that the Assyrians added an extra month from time to time, but we do not
>know whether they had developed a special rule for doing so or whether the
>priests proclaimed the necessity for an extra month from observation. If
>they made every third year a year of 13 lunations, their three-year period
>would cover 1,0911/2 days (using their value of 291/2 days for one
>lunation), or just about 4 days too short. In one century this mistake would
>add up to 133 days by their reckoning (in reality closer to 134 days),
>requiring four extra lunations per century.
>
>1. The correct figures are lunation: 29 d, 12 h, 44 min, 2.8 sec (29.530585
>d); solar year: 365 d, 5 h, 48 min, 46 sec (365.242216 d); 12 lunations: 354
>d, 8 h, 48 min, 34 sec (354.3671 d).
>We now know that an eight-year period, consisting of five years with 12
>months and three years with 13 months, would lead to a difference of only 20
>days per century, but we do not know whether such a calendar was actually
>used.
>
>The best approximation that was possible in antiquity was a 19-year period,
>with 7 of these 19 years having 13 months. This means that the period
>contained 235 months. This, still using the old value for a lunation, made a
>total of 6,9321/2 days, while 19 solar years added up to 6,939.7 days, a
>difference of just one week per period and about five weeks per century.
>Even the 19-year period required constant adjustment, but it was the period
>that became the basis of the religious calendar of the Jews. The Arabs used
>the same calendar at first, but Muhammed forbade shifting from 12 months to
>13 months, so that the Islamic religious calendar, even today, has a lunar
>year of 354 days. As a result the Islamic religious festivals run through
>all the seasons of the year three times per century.
>
>The Egyptians had a traditional calendar with 12 months of 30 days each. At
>one time they added 5 extra days at the end of every year. These turned into
>a 5-day festival because it was thought to be unlucky to work during that
>time.
>
>When Rome emerged as a world power, the difficulties of making a calendar
>were well known, but the Romans complicated their lives because of their
>superstition that even numbers were unlucky. Hence their months were 29 or
>31 days long, with the exception of February, which had 28 days. However, 4
>months of 31 days, 7 months of 29 days, and 1 month of 28 days added up to
>only 355 days. Therefore, the Romans invented an extra month called
>Mercedonius of 22 or 23 days. It was added every second year.
>
>Even with Mercedonius, the Roman calendar was so far off that Caesar,
>advised by the astronomer Sosigenes, ordered a sweeping reform in 45 B.C.E.
>One year, made 445 days long by imperial decree, brought the calendar back
>in step with the seasons. Then the solar year (with the value of 365 days
>and 6 hours) was made the basis of the calendar. The months were 30 or 31
>days in length, and to take care of the 6 hours, every fourth year was made
>a 366-day year. Moreover, Caesar decreed the year began with the first of
>January, not with the vernal equinox in late March.
>
>This was the Julian calendar, named after Julius Caesar. It is still the
>calendar of the Eastern Orthodox churches. However, the year is 111/2
>minutes shorter than the figure written into Caesar's calendar by Sosigenes,
>and after a number of centuries, even 111/2 minutes add up.
>
>While Caesar could decree that the vernal equinox should not be used as the
>first day of the new year, the vernal equinox is still a fact of nature that
>could not be disregarded. One of the first (as far as we know) to become
>alarmed about this was Roger Bacon. He sent a memorandum to Pope Clement IV,
>who apparently was not impressed. But Pope Sixtus IV (who reigned from 1471
>to 1484) decided that another reform was needed and called the German
>astronomer Regiomontanus to Rome to advise him. Regiomontanus arrived in
>1475, but one year later he died in an epidemic, one of the recurrent
>outbreaks of the plague. The pope himself survived, but his reform plans
>died with Regiomontanus.
>
>Less than a hundred years later, in 1545, the Council of Trent authorized
>the then pope, Paul III, to reform the calendar once more. Most of the
>mathematical and astronomical work was done by Father Christopher Clavius,
>S.J. The immediate correction, advised by Father Clavius and ordered by Pope
>Gregory XIII, was that Thursday, Oct. 4, 1582, was to be the last day of the
>Julian calendar. The next day was Friday, with the date of October 15. For
>long-range accuracy, a formula suggested by the Vatican librarian Aloysius
>Giglio (latinized into Lilius) was adopted: every fourth year is a leap year
>unless it is a century year like 1700 or 1800. Century years can be leap
>years only when they are divisible by 400 (e.g., 1600). This rule eliminates
>three leap years in four centuries, making the calendar sufficiently correct
>for all ordinary purposes.
>
>Unfortunately, all the Protestant princes in 1582 chose to ignore the papal
>bull; they continued with the Julian calendar. It was not until 1698 that
>the German professor Erhard Weigel persuaded the Protestant rulers of
>Germany and of the Netherlands to change to the new calendar. In England the
>shift took place in 1752, and in Russia it needed the revolution to
>introduce the Gregorian calendar in 1918.
>
>The average year of the Gregorian calendar, in spite of the leap year rule,
>is about 26 seconds longer than the earth's orbital period. But this
>discrepancy will need 3,323 years to build up to a single day.
>
>Modern proposals for calendar reform do not aim at a "better" calendar, but
>at one that is more convenient to use, especially for commercial purposes. A
>365-day year cannot be divided into equal halves or quarters; the number of
>days per month is haphazard; the months begin or end in the middle of a
>week; a holiday fixed by date (e.g., the Fourth of July) will wander through
>a week; a holiday fixed in another manner (e.g., Easter) can fall on 35
>possible dates. The Gregorian calendar, admittedly, keeps the calendar dates
>in reasonable unison with astronomical events, but it still is full of minor
>annoyances. Moreover, you need a calendar every year to look up dates; an
>ideal calendar should be one that you can memorize for one year and that is
>valid for all other years, too.
>
>In 1834 an Italian priest, Marco Mastrofini, suggested taking one day out of
>every year. It would be made a holiday and not be given the name of a
>weekday. That would make every year begin with January 1 as a Sunday. The
>leap-year day would be treated the same way, so that in leap years there
>would be two unnamed holidays at the end of the year. About a decade later
>the philosopher Auguste Comte also suggested a 364-day calendar with an
>extra day, which he called Year Day. Since then there have been other
>unsuccessful attempts at calendar reform.
>
>
>                           THE END
>
>

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