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On 15 September, the Fourth Doctor and Sarah Jane Smith visited the town of St Thomas to see P. T. Barnum's circus. After the show ended, the animals that performed were transported across a nearby train-track to their boxcars. As the elephantsJumbo and Tom Thumb were transported across the track, a train came along. Jumbo attempted to run away from it, but was unsuccessful. The impact killed Jumbo. If it weren't for the Doctor's TARDIS blocking the only path off of the train-track, Jumbo would have been able to avoid the train and survive. (AUDIO: The Wondrous Box)