During Richard Nixon’s presidency, members of his staff compiled a list of political opponents. As White House counsel John Dean put it, the purpose of the list was to “use the available federal machinery to screw our political enemies.” In addition to the original list of 20 “enemies,” Nixon’s staff put together a larger collection of political opponents, which Dean presented to the Senate Watergate Committee in 1973. This list included various politicians, journalists, business leaders, celebrities, and institutions. Think you can figure out who was on those lists? Let’s find out.
Take the Quiz: Were They On Nixon’s Enemies List?
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One of the northern provinces of the Netherlands, Friesland, has 11 ancient cities loosely separated by a series of canals and lakes. When the weather gets cold enough, the ice gets thick enough to allow for a huge, nationally renowned skating race through each of the cities.
Called the Elfstedentocht (or in English, the Eleven Cities Tour), the race is a roughly 200 kilometer trek across the frozen landscape and takes, at its fastest, over six hours. For the race to occur, the ice must be at least 15 centimeters thick throughout the course — which is rare. While the tradition of skating from city to city dates back to 1760, the race was not formalized until 1909. But in the last century, the Elfstedentocht has only taken place 15 times and not since 1997.
Former mental_floss writers John and Hank Green have started a new nerdy thing on YouTube, and it’s pretty great: Crash Course is a series of educational videos covering World History (John) and Biology (Hank). The production values are high (including animation, HD, all that good stuff), and each video is about ten minutes long. My favorites so far are John’s videos on World History — he promises a 40-part series (co-written with his high school history teacher), though only three parts have been posted so far. Check ‘em out below.
“Together we will learn how, in a mere fifteen thousand years, humans went from hunting and gathering–[interrupted by younger self offscreen]“
“Why am I alive? Also, why don’t I have any eyes?”
The team over at smosh.com likes useless flyers. I have to admit, I do too! I’ve combed through a bunch of their posts for you and present to you now, my 12 favorites… As always, tell us which you like best in the comments below!



Cupcake image via Shutterstock
On the 11th day of each month, we post (roughly) 11 ’11 lists’ on various topics throughout the day. Because February 11th is a Saturday and we’ll be setting up the mental_floss booth at the New York Toy Fair that day, we’re moving the elevensanity to Friday. Don’t freak out.
We’ll put up the first list shortly after midnight.
Reader rccola20 wrote in to ask, “Are bloodhounds really that much better at tracking than other dog breeds?”

Bloodhound image via Shutterstock
You always see them hunting down fugitives in the movies, but is that just Hollywood, or are bloodhounds really the best smellers around?
Bloodhounds are pretty much the best in the business. Sometimes called noses with paws, their skills as trackers come from the high number of olfactory receptors — or “scent cells” — tucked up in their wet noses, which detect odor molecules. A human’s olfactory membrane is about the size of a postage stamp and contains 5 million receptors. A large dog like a German Shepherd, meanwhile, has a larger membrane and about 225 million receptors.

Whether celebrity political endorsements actually matter is up for debate, and it obviously depends on the celebrity. How well do you remember the endorsements in this quiz?
Take the Quiz: Celebrity Political Endorsements

During the least colorful part of the year, after the Christmas lights are stashed away and before spring flowers blossom, we console ourselves by looking at seed catalogs or a nice blog post about the flowers to come. I’ve heard that people are seeing daffodil sprouts around town, which is exciting. No blooms yet, at least where I am, but the daffodils (and spring) will be here soon! Photograph by Flickr user Gail Johnson.
Daffodils, Narcissus, jonquils, March blooms, these terms all refer to the flower that comes back every spring on roadsides, hills, and flower gardens over a large part of the Northern Hemisphere. They are a part of the Amaryllis family, and many types grow wild.

Good luck with today’s mentalfloss.com Brain Game Think Thursday challenge:
What’s the only U.S. state that is home
to TWO Ivy League schools,
and what are the names of those schools?