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Octagon and October, and calendars in general
By Rachel Grant (P1159) on Sunday, September 12, 1999 - 07:29 am:

In view of "Septagons - are they real" (a discussion I read), I was wondering if anyone knew anything about this.

If an Octagon has eight sides, why is the month October the 10th month? I heard it was because some ancient civilisation added a couple of months in to our year. Is this true?

Rachel

By Graham Lee (P1021) on Sunday, September 12, 1999 - 10:03 pm:

Yes it is. There used to be 10 months of 36 days =360 day year, but when Augustus Caesar decided to make the year 365 days long (as indeed it is), he added two months July (after Julius) and August (no comment). There for September (7th month)-December (10th month) have been shifted along, and no longer make sense.
Also on the subject of calendar reform, Pope Gregory XII mucked around with it so much that Christmas (which used to be Jan 1st A.D.1) is now Dec 25 B.C.27! Stupid man

By Alex Barnard (Agb21) on Monday, September 13, 1999 - 12:08 pm:

The reason for Caesar adding two extra months (which was in 46BC if you want to know) was not only to get his name in the calendar but to bring the number of days in the year to be much closer to the number of days the earth takes to orbit the sun. It takes about 365days 5hrs 48mins and 46sec to orbit the sun. So Caesar made the year 365days and 6hrs long. This extra 1/4 of a day is why we have leap years.

This isn't too bad but it does mean that the year is 11mins 14sec too long. By the time of Pope Gregory XIII (not the XII) these small number of minutes had accumulated to become 10 days. So in October 1582 he corrected this by removing 10 days. So the days in October this year went 1,2,3,4,15,16,... He also changed the leap year system to make years much closer to their true value. He dropped the lear year every 100 years except that he put it back in every 400 years. This makes the year 365days 5hours 49minutes 12seconds long. So we are now only out by about 26 seconds/year. Currently we have an even more accurate calendar by including things called 'leap-seconds' where we make the next year start a second early or late to make our years almost perfect.

England and her colonies refused to accept the Gregorian calendar until the year 1752 (so in that time our dates were 10 days out from other countries). When we did change over something even stranger happened. It was the practice in Rome to start the year on March 25th (the Feast of the Annunciation --- when Gabriel told Mary that she would be the mother of Christ after 9 months). This is why Christmas is now Dec 25th (9 months after March 25th). And also why our tax year starts and ends where it does. So to get in line with this the calendar went

Nov 1751, Dec 1751, Jan 1751, Feb 1751, Mar 1751

So the year number didn't change until March 25th when it skipped to 1752. We then also had to skip 11 days to come into line with the Gregorian calendar.

Some countries waited even longer --- Russia changed to Gregorian in 1918! Some countries use totally different calendars.

This all leads to dates being very confusing at this time in history. This is why tombstones sometimes give both dates. Also why people can be born in Jan 1751 and die in May 1752 and still be under a year old! Or even be born in Jan 1751 and then die in Jan 1751 and be over a year old!

AlexB.

By Anonymous on Sunday, May 21, 2000 - 05:25 pm:

Doesn't the amount of time in our day go over the amount of time the earth takes to orbit its axis, so shouldn't the times of day (daytime, nighttime) be constantly changing (very slowly) all the time?