One hundred years ago, visitors to Cave of the Winds in Colorado carried candles and lanterns along ghostly, dark halls that seemed to have no end. Today, cave enthusiasts can spend an hour or more with an authentically ...Read More

The Liberty Bell was not made in the United States and it was not rung on the first Fourth of July. It was cast in London in 1752, cracked in 1835, and was not named "Liberty" until the 1830s in memory of slaves seeking ...Read More

Recycled glass uses only two-thirds the energy needed to manufacture glass from scratch. That means for every soft drink bottle that is recycled, enough energy is saved to run a television set for an hour and a half.

Among his many achievements, the astronomer Johannes Kepler chalked up one about man's inner world. It was Kepler who realized that man's visual apparatus is so constructed that it can produce only inverted images.

A beautiful mirage called the Fata Morgana appears in the Straits of Messina, between Sicily and Italy. It is an image of a town in the sky, but it seems more like a fairy landscape than a real town. It is believed to be a...Read More

Yes. Under the Julian calendar, February had 29 days and the other months alternated evenly between 30 and 31 days. Because July had 31 days, the month following it was supposed to have 30 days. But that was the month that...Read More