Early Time Travel? Why Britain Lost 11 Days in 1752

For one year, more than two centuries ago, September 3-13 didn't exist in the British Empire. Overnight, citizens were transported from Wednesday, September 2, 1752 to Thursday, September 14.

The loss of 11 days was intentional. Britain implemented the Gregorian calendar in place of the pre-existing Julian calendar, the main timeline used worldwide after Julius Caesar introduced it in 45 BCE. And in order to properly transition, the empire needed to move ahead in the month.

The Julian calendar was designed around the assumption that each year is 365 days and six hours long. The result: every four years an extra day was added to February—much like the leap years we know now. However, this format resulted in an lag of approximately 18 hours each century. As time passed, the Julian calendar became increasingly inaccurate, and the Catholic Church was particularly uneasy with Easter gradually moving farther and farther away from the spring equinox.

The Gregorian calendar attempts to correct this lapse and more closely align the calendar year with the solar year, the length of time it takes the Earth to complete one orbit around the sun. In order to do this, the qualifications for a leap year became more complicated. The calendar system demanded that there can only be an extra day in years that are divisible by four. If the year could also be evenly divided by 100, it was not a leap year unless it could also be evenly divided by 400. For instance, 1900 would have previously been a leap year, but it no longer was since it didn’t meet the updated guidelines. Another notable change is that the New Year, which previously began on March 25 in Britain, moved to January 1.

Some accounts claim the changes didn't go over smoothly. Citizens reportedly took to the streets, rioting and demanding, “Give us our 11 days.” This legend is reinforced by interpretations of William Hogarth’s 1755 painting titled "An Election Entertainment” that depicts Whig candidates at a tavern dinner and a stolen banner that reads "Give us our Eleven Days.” However, Historic U.K. reports that historians now believe stories of the riots are exaggerated and the protests are simply an urban myth.

It is also believed that many Protestant countries pushed back on adopting the Gregorian calendar because it was strongly supported by the Catholic Church. The Gregorian calendar was introduced in 1582 and Catholic countries like Spain, Italy, and Portugal put into place that same year. However, Protestant Germany held out until 1700 and England, of course, waited until 1752.

Whether or not the English citizens were unhappy with the loss of 11 days, one resident of the 13 Colonies, which was part of the British Empire at the time, reportedly didn’t mind. Benjamin Franklin praised the switch, writing, “It is pleasant for an old man to be able to go to bed on September 2, and not have to get up until September 14."

A Simple Trick For Figuring Out the Day of the Week For Any Given Date

People typically remember anniversaries in terms of dates and years, not days of the week. If you can’t remember whether you got married on a Saturday or Sunday, or don't know which day of the week you were born on, there’s a simple arithmetic-based math trick to help you figure out sans calendar, according to It's Okay To Be Smart host Joe Hanson.

Mathematician John Conway invented the so-called Doomsday Algorithm to calculate the day of the week for any date in history. It hinges on several sets of rules, including that a handful of certain dates always share the same day of the week, no matter what year it is. (Example: April 4, June 6, August 8, October 10, December 12, and the last day of February all fall on a Wednesday in 2018.) Using this day—called an “anchor day”—among other instructions, you can figure out, step by step, the very day of the week you’re searching for.

Learn more about the Doomsday Algorithm in the video below (and if it’s still stumping you, check out It’s OK to Be Smart’s handy cheat sheet here).

Why Was February Chosen for Black History Month?

Every February since 1976, the United States has celebrated the achievements of African-Americans during Black History Month. The month-long celebration puts those accomplishments and milestones in focus via the media and in classrooms.

But why February? Was that part of the calendar chosen for any specific purpose?

It was. Black History Month began as “Negro History Week,” a label applied by historian Carter G. Woodson in 1926. Woodson was bothered by the fact that many textbooks and other historical reviews minimized or ignored the contributions of black figures. Along with his Association for the Study of Negro Life and History—later the Association for the Study of African American Life and History—Woodson earmarked the second week in February to raise awareness of these stories.

Woodson chose that week specifically because it covered the birthdays of Frederick Douglass (February 14) and Abraham Lincoln (February 12). The ensuing publicity led many mayors and college campuses to recognize the week; through the years, the groundswell of support allowed the occasion to stretch throughout the entire month.

In 1976, President Gerald Ford made Black History Month official, saying that he was urging everyone to “seize the opportunity to honor the too-often neglected accomplishments of black Americans in every area of endeavor throughout our history.”

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