> Also Feb 30th happened in 1712 in Sweden September 1752 was even stranger, with 11 missing days: > The Gregorian calendar reform was adopted by the Kingdom

> Also Feb 30th happened in 1712 in Sweden September 1752 was even stranger, with 11 missing days: > The Gregorian calendar reform was adopted by the Kingdom of Great Britain, including its possessions in North America (later to become eastern USA and Canada), in September 1752. As a result, the September 1752 cal shows the adjusted days missing. This month was the official (British) adoption of the Gregorian calendar from the previously used Julian calendar. This has been documented in the man pages for Sun Solaris as follows. "An unusual calendar is printed for September 1752. That is the month when 11 days were skipped to make up for lack of leap year adjustments. $ cal 9 1752 September 1752 S M Tu W Th F S 1 2 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 https://en.wikipedia.org/wiki/Cal_(command)#Quirks_(1752) https://en.wikipedia.org/wiki/Cal_(command)#Quirks_(1752)