Britain and its colonies eliminated 11 days (not 10), following
September 2, 1752.
From "A.D. 1751. Anno vicesimo quarto GEORGII II. CAP. XXIII.
An Act for Regulating the Commencement of the Year; and for
Correcting the Calendar now in Use.":
"... and that the natural Day next immediately following the said 2nd Day of
*September* [1752], shall be called, reckoned and accounted to be the 14th
Day of *September*, omitting for that Time only the 11 intermediate nominal
Days of the common Calendar;
and that the several natural Days, which shall follow and succeed next after
the said 14th Day of *September*, shall be respectively called, reckoned and
numbered forwards in numerical Order from the said 14th Day of *September*,
according to the Order and Succession of Days now used in the present
Calendar; "
Added a caution note on using cal for very old dates.
Problem mentionned in PR 5215 by John Franklin (franklin@bev.net).
Thanks to Perry Metzger for his comments and for reviewing this man page.