10 Days Missing
play clip > cal9_1752
The dates September 3rd thru 13th are missing in the 1752 calendar. It is not a mistake. How can you view this calendar from the 18th-century on your computer? Launch the Terminal. Type: cal 9 1752
Notice the dates missing between September 2nd and 14th. There’s a Wikipedia post that explains this gap.
Source: Wikipedia.org
September 3–September 13 inclusive - These dates are omitted from the calendar in Britain as part of the adoption of the Gregorian calendar in the British Empire, to correct the 11-day discrepancy between the Old Style and New Style dates.
“In England, the year 1751 was a short year of 282 days, running from 25 March to 31 December. 1752 began on 1 January. To align the calendar in use in England to that in use on the continent, the changes introduced in 1582 by the Gregorian calendar were adopted with effect in 1752. To this end, the calendar was advanced by 11 days: 2 September 1752 was followed by 14 September 1752. The other changes brought about by Gregory were also adopted.
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The Gregorian calendar is the most widely used calendar in the world today. It was first proposed by the Calabrian doctor Aloysius Lilius, and decreed by Pope Gregory XIII, after whom it was named, on 24 February 1582 by papal bull Inter gravissimas. It is a reform of the Julian calendar.
Years in the reformed calendar continue the numbering system of the Julian calendar, which are numbered from the traditional Incarnation year of Jesus, which has been labeled the "anno Domini" (AD) era, and is sometimes labeled the "common era" (CE), otherwise known as the "Christian Era".
The changes made by Gregory corrected the drift in the civil calendar which arose because the mean Julian calendar year (exactly 365.25 days) was slightly too long, causing the vernal equinox, and consequently the date on which Easter was being celebrated, to drift slowly forward in relation to the civil calendar and the seasons. The Gregorian calendar system dropped 10 days to bring the calendar back into synchronization with the seasons and, to keep it there, adopted the following leap year rule:
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100; the centurial years that are exactly divisible by 400 are still leap years. For example, the year 1900 was not a leap year; the year 2000 was a leap year”.