English cavalryman Philip Astley stages the first modern circus in London. Trick riders, acrobats, clowns, trained animals, and other familiar components of the circus have existed throughout recorded history, but it was not until the late 18th century that the modern spectacle was born. Astley found that if he galloped in a tight circle, centrifugal force allowed him to perform seemingly impossible feats on a horse's back. His trick riding received such a favorable response that he soon hired other equestrians, a clown, and musicians and in 1770 built a roof over his ring and called the structure Astley's Amphitheatre. Later, a competitor coined the term circus to describe this new form of entertainment, referring to the Roman name for the circular theaters where chariot races were held. __