Discover 50 Super Weird Historical Facts 2 years ago Prev Article Next Article Prev23 of 51NextUse your ← → (arrow) keys to browse Fact 22: In the 19th century, doctors used leeches for medicinal purposes. The practice of bloodletting using leeches was believed to balance the body’s humors and treat a range of ailments. Prev23 of 51NextUse your ← → (arrow) keys to browse Facebook Prev Article Next Article