Friday links

Here's what happens when you crack your knuckles, including the researcher who cracked the knuckles in one hand only for over 60 years to see if he'd get arthritis. Related: The Science of Knuckle Cracking.

How a Guy From a Montana Trailer Park Overturned 150 Years of Biology

The legend of Blackbeard’s silver-plated skull. Kind of related: The Swashbuckling History of Women Pirates.

April 22 is Earth Day: here's the story of the co-founder who killed then composted his girlfriend.

Inside the FBI’s Colossal Pre-Computer Fingerprint Factory.

Artificial Heart Update: A simple artificial heart could permanently replace a failing human one.

ICYMI, Wednesday's links are here, and include the anniversary of the 1906 earthquake and fire that destroyed 80% of San Francisco, that time Kansas locked up more than 5,000 women and girls for having STDs, why it's almost impossible to throw a 110 mph fastball, and "T'was the eighteenth of April in seventy-five": the midnight ride of William Dawes and Samuel Prescott (and Paul Revere).

Tuesday's links

April 25th is ANZAC (Australian and New Zealand Army Corps ) Day, the anniversary of the Battle of Gallipoli.

Seven Things You Didn’t Know About Medieval Dragons.

Is a Drunk Witness a Bad Witness?

It's Oliver Cromwell's birthday - here's his excellent speech throwing out the corrupt Parliament, with bonus Monty Python.

The World's Most Stubborn Real Estate Holdouts.

Inside the FBI’s Colossal Pre-Computer Fingerprint Factory.

ICYMI, Friday's links are here, and include the science of cheap wine, Earth Day's murderous co-founder, a 1964 coffee revolt, fighting communism with jazz, and a 1983 episode of The Family Feud that pitted the cast of Gilligan's Island against the cast of Batman.

Wednesday links

On March 30, 1848, Niagara Falls Ran Dry, with bonus Niagara Falls sketch by Abbott & Costello and The Three Stooges.

Before computers: Inside the FBI’s Colossal Fingerprint Factory.

In this 2.5 minute video, Carl Sagan lucidly explains how Eratosthenes not only deduced a spherical earth, but accurately calculated its diameter in 200 B.C.

For Van Gogh’s birthday, his recently-discovered sketchbooks and the unexpected math behind "Starry Night"

Prozac in the Water Makes Fighting Fish More Mellow.

The Demonic Origins of Ventriloquism.

ICYMI, Friday's links are here, and include the history and calculations behind Easter's varying dates, a gallery of Easter bunnies terrifying children, and a collection of videos of violence against marshmallow peeps.