 Complete the following phrase:  Horses appeared in Western European theater in the second half of the 18th century, both on stage and in aerial stunts flying Pegasus. Hippodrama emerged at the turn of the 19th century in England, introduced by Philip Astley in outdoor settings. At this time, the Licensing Act of 1737 was in effect, which allowed only three venues to perform legitimate theater patent theatre. These included Covent Garden, Drury Lane, and the summer theatre in the Haymarket. These theaters had patents on real drama. Other theaters, such as Astleys Amphitheatre and the Royal Circus and Equestrian Philharmonic Academy latterly the Surrey Theatre, were only granted licenses for public dancing and music and for other public entertainments of the like kind. Astleys horse acts in his circus were allowed within his license. However, Astley wanted to produce shows more like legitimate theater. He soon realized that he could produce real drama as long as the action was performed on horseback. Thus, hippodrama was born. He adapted common stories and plays in a way where they could be performed on horses. Not only that, but the horses were the main actors. The horses had their own business, or leading actions, to perform that helped carry out the plot. Also at this time, gradual closing of country fairs and discharge of cavalrymen and grooms after the end of the 