The Montgolfier Brothers, Joseph and Jacques, were pioneers of hot air ballooning in the late 18th century in France. Through experiments, they discovered that heating air inside a large bag made of silk and paper caused it to rise. In their first test, a balloon carrying no passengers rose over half a mile high. Later tests included animals in the basket and attracted an audience including the King and Queen of France. Finally, on November 21, 1783, two men became the first humans to fly in a Montgolfier hot air balloon, traveling over 10 miles in 20 minutes.