Although panoramas cannot be called a form of theatre, they had an important impact on scene design for both the legitimate and musical stage, and they were marketed to the public, along with live theatre and dime museums, under the category of amusements. After paying admission, a patron would climb a spiral staircase to a viewing platform from which one could contemplate an encircling painted vista of a city or a battlefield, with three-dimensional elements in the foreground. Panoramas were novelties in Europe around 1800, but enjoyed worldwide popularity by the 1880s. Kansas City, for example, had two panoramas in operation in 1887, each showing a Civil War battle scene. A mid-19th-century variation was the moving panorama; this involved scrolling across the stage a huge canvas depicting the changes of scenery over a vast distance. When actors or horse-drawn chariots (as in Ben-Hur) moved in the opposite direction on a treadmill in front of the spooling canvas, the illusion of a journey past changing scenery was effected.
The Historical Dictionary of the American Theater. James Fisher.