gallop, which had all of their eight legs moving in coordinated motion; he also produced footage of a fleet of rocketships emerging from a Martian volcano. Metro-Goldwyn-Mayer was to release the cartoons, and the studio heads were enthusiastic about the series. The test footage, produced by 1936, received negative reactions from film exhibitors across the U.S., especially in small towns; many gave their opinion that the concept of an Earthman on Mars was just too outlandish an idea for midwestern American audiences to accept. The series was not given the go-ahead, and Clampett was instead encouraged to produce an animated Tarzan series, an offer that he later declined. Clampett recognized the irony in MGM's decision, as the Flash Gordon movie serial, released in the same year by Universal Studios, was highly successful. He speculated that MGM believed that serials were played only to children during Saturday matinees, whereas the John Carter tales were intended to be seen by adults during the evening. The footage that Clampett produced was believed lost for many years, until Burroughs' grandson, Danton Burroughs, in the early 1970s found some of the film tests in the Edgar Rice Burroughs Inc. archives. Had A Princess of Mars been released, it might have preceded Walt Disney's Snow White and the Seven Dwarfs to become the first American feature-length animated film. Disney progression During the late 1950s, stop-motion animation effects director Ray Harryhausen expressed interest in filming the novels, but it was not until the 1980s that producers Mario Kassar and Andrew G. Vajna bought the rights for Walt Disney Studios via Cinergi Pictures, with a view to creating a competitor to Star Wars and Conan the Barbarian. Ted Elliott and Terry Rossio were hired to write, while John McTiernan and Tom Cruise were approached to direct and star. The project collapsed because McTiernan realized that visual effects were not yet advanced enough to recreate Burroughs' vision of Barsoom. The project remained at Disney, and Jeffrey Katzenberg was a strong proponent of filming the novels, but the rights eventually returned to the Burroughs estate. Paramount effort Producer James Jacks read Harry Knowles' autobiography, which lavishly praised the John Carter of Mars series. Having read the Burroughs' novels as a child, Jacks was moved to convince Paramount Pictures to acquire the film rights; a bidding war with Columbia Pictures followed. After Paramount and Jacks won the rights, Jacks contacted Knowles