[tz] Leap year bugs

[Clive D.W. Feather]

Brian Inglis said:
>>> [OT: Note the date issued on the Julian Calendar: as it was not an O.S. leap
>>> year this was not the leap day; the year changed on Lady Day March 25 (O.S.);
>> In England but not in Scotland, which had moved to the 1st January rule well
>> before.

I meant well before 1752; I don't know when (or if they ever used the Lady
Day convention).

> Probably for continental commercial reasons regardless of religious
> considerations, while keeping an eye on the crown to free up down south.

Union of crowns was 1603; union of Parliaments was 1707.

>> It's my understanding that the insertion of 29th February was done on the
>> basis of the Scottish system, not the English one, so there was a 29th
>> February in 1743 and in 1747.
> Was there a different Julian/O.S. system in Scotland, and are there docs/refs?

I didn't make that clear, did I?

My understanding (and, no, I don't have references) is that all of Europe
had 29th February (whether the leap day is VI Kal.Mar. or 29th February is
a notational matter and not relevant) in the same Februaries, so that the
29th February would be in 1743 and 1747 in England but in 1744 and 1748 in
Scotland *but it's the same February*.

>>> still observed as HM gov fiscal and taxation year end April 5 (N.S.) as they
>>> were not giving up 11 days of taxes in 1751/2!]
>> Just 1752; that was the first year that England changed rule. So 1751 was
>> only 278 days long in England (and had no January or February at all);
>> February 29th 1752 existed throughout the Union.
> 
> You mean as January/February/March until 24th were still considered 1750 (O.S.)?

Yes.

> Did the Empire change year numbering on January 1 from O.S. to N.S., prior to
> changing the calendar from Julian to Gregorian on September 14?

Yes: this was specified in the New Calendar Act.

England     Scotland
...         ...
1747-12-31  1747-12-31
1747-01-01  1748-01-01
...         ...
1747-02-28  1748-02-28
1747-02-29  1748-02-29
1747-03-01  1748-03-01
...         ...
1747-03-24  1748-03-24
1748-03-25  1748-03-25
...         ...
1748-12-31  1748-12-31
1748-01-01  1749-01-01
...         ...
1748-02-28  1749-02-28
1748-03-01  1749-03-01
...         ...
1748-03-24  1749-03-24
1749-03-25  1749-03-25
...         ...
1749-12-31  1749-12-31
1749-01-01  1750-01-01
...         ...
1749-02-28  1750-02-28
1749-03-01  1750-03-01
...         ...
1749-03-24  1750-03-24
1750-03-25  1750-03-25
...         ...
1750-12-31  1750-12-31
1750-01-01  1751-01-01
...         ...
1750-02-28  1751-02-28
1750-03-01  1751-03-01
...         ...
1750-03-24  1751-03-24
1751-03-25  1751-03-25
...         ...
1751-12-31  1751-12-31
1752-01-01  1752-01-01
...         ...
1752-02-28  1752-02-28
1752-02-29  1752-02-29
1752-03-01  1752-03-01
...         ...
1752-03-24  1752-03-24
1752-03-25  1752-03-25
...         ...
1752-09-02  1752-09-02
1752-09-14  1752-09-14
...         ...
1752-12-31  1752-12-31
1753-01-01  1753-01-01
...         ...


-- 
Clive D.W. Feather          | If you lie to the compiler,
Email: clive at davros.org     | it will get its revenge.
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