The Writer’s Almanac has a informative discussion of leap years and calendars. It begins with:
Today is Leap Day, the extra day that we tack on to February every four years to keep the calendar in time with the seasons. We do this because the earth does not orbit the sun in a nice round 365 days, but rather in 365 days, 5 hours, 48 minutes, and 45 seconds.
And includes this:
When Great Britain finally accepted the Gregorian calendar in 1751, eleven days had to be deleted from the year. The change led to antipapal riots, because people believed the Pope had shortened their lives. Mobs gathered in the streets, chanting, “Give us back our eleven days!” When the British colonies in America made the change the following year, Ben Franklin wrote in an editorial, “Be not astonished, nor look with scorn, dear reader, at . . . the loss of so much time. . . . What an indulgence is here, for those who love their pillow, to lie down in peace on the second [day] of this month and not awake till the morning of the fourteenth.”