This is no ordinary mummy. It did not originate from ancient Egypt or the Inca. It is not thousands of years old, nor is it wrapped in bandages. (In fact, if you look closely, you'll see this person died wearing knee-high stockings.)

This mummy is from North America. When he was alive, this person live in 18th-century Philadelphia. During a construction project in Philadelphia in 1875, the body was unearthed by accident.

But that's not what makes this mummy special.

Unlike other mummies which are kept dry to ensure preservation, this mummy was exposed to water, which seeped into the casket and turned the fats in his body to soap. Hence the mummy's nickname: "Soapman."

Saponification, a chemical reaction used to create soap for millennia, literally means "soap making" in Latin. When water reacts with the fats and oils, a reaction called hydrolysis, the result is glycerol and soap.

This process is common when bodies have been exposed to water. The end result is called adipocere, or grave wax....