An elephant was executed by hanging in 1916.

Charlie Sparks, the owner of a small-time circus called Sparks World Famous Shows, was touring the southern United States. Along for the trip was Mary, a 30-year-old pachyderm that Sparks claimed was the largest animal on Earth, could play the horn, had a .400 batting average, and could kill a man. It turns out only one of those was true.

The many witnesses of the following events offer various accounts of what happened on September 12, 1916, that fateful day when Sparks World Famous Shows came to Kingsport, Tennessee. For whatever reason, whether by mistake or malicious intent, Mary the elephant killed novice elephant handler, Red Eldridge. For her crimes, “Murderous Mary” was sentenced to be executed the next day.

After deciding that there was no way to produce enough electricity to electrocute Mary, Sparks decided instead to execute her with a public hanging. 2,500 people showed up to watch the elephant be hanged at the Clinchfield Railyards. She was so heavy that the chain around her neck snapped shortly after she died. They then buried her in a grave dug by a steam shovel.

Source: http://www.blueridgecountry.com/archive/mary-the-elephant.html

The Tonle Sap River in Cambodia flows North for almost half the year and then South for the rest of the year.

Monsoon rains fill the neighboring Mekong River with so much water that the Tonle Sap river is forced to flow backwards into the Tonle Sap Lake. The lake swells to 5 times its normal size, providing Cambodians with giant Mekong catfish for food.

Overfishing, and damming of the Mekong river may disrupt this important seasonal occurrence. Fishermen have been catching fewer and smaller fish in recent years, and Mekong catfish is now endangered.

Google was once named "BackRub".

Creators Larry Page and Sergey Brin met while at Stanford University and collaborated on a web search engine called "BackRub." Over time, the engine became too large for the university's servers and the pair decided it was time for a name change. They eventually came up with the name "Google," which was based on the word "googol" - a mathematical term for the number 1 followed by 100 zeros! They believed this word encapsulated their goal of organizing the limitless amounts of information stored across the World Wide Web.

Spicy food can make your nose run because of a chemical compound that irritates your mucus membranes.

This chemical compound is called capsaicin, and it is found in such foods as hot peppers. It is a strong irritant that can irritate both the mucus membranes of the nose and the tear ducts of a person's eyes. This is why oftentimes your nose can run and your eyes water while enjoying a spicy meal. Capsaicin can also dilate blood vessels, which is why people also tend to turn red in the face!

Angel Falls in Venezuela is so high that the water often evaporates before it can land.

At over 3200 feet, it's the tallest waterfall in the world! That's roughly 20 times taller than the Niagara Falls. The height of the longest uninterrupted fall for water in Angel Falls is over 2600 feet. In the dry season the water will evaporate before hitting the bottom of the falls!

The initials of Homer Simpson's creator are hidden in his ear and hair.

If you look closely, you can see that Homer's little squiggle of hair and right ear resemble an 'M' and a 'G.' Those letters stand for the name of his creator, Matt Groening! Groening originally designed the features to resemble the letters much more closely, but he thought the ear was too distracting. He still draws the ear as a 'G' when he draws pictures of Homer for fans though!

The Lincoln Memorial has a typo on it that is still partially visible.

Two of Abraham Lincoln's most important speeches are carved on the inner walls of the Memorial: the Gettysburg Address on the north wall, and his Second Inaugural Address on the south wall. While carving the Second Inaugural Address, the engraver accidentally chiseled an 'E' instead of an 'F' in the word "future!"

The mistake was easily corrected by filling in the extra line, but the mistake is still quite visible if you look closely. By the way, Abraham Lincoln's body is not buried in the Lincoln Memorial. It's actually in Springfield, Illinois. And the position of the statue's hands are not sign language.