Film 3: Jumbo: Owing to test planner’s concern that the Trinity device could fizzle with high explosives spreading immensely valuable plutonium across the desert, General Groves approved the construction of a huge steel vessel, nicknamed Jumbo, to contain the bomb and prevent such a loss With growing confidence that the “gadget” would work as planned, Jumbo was not used for its purpose, but placed in a tower 800 yards from ground zero. This film shows Jumbo after its arrival by train from Ohio at a railroad spur, 30 miles from the Trinity site, where it was transferred onto a 64 wheel trailer. (Excerpt from LANL video, “Trinity 2”) (For the Jumbo story, see Robert S. Norris, Racing for the Bomb: General Leslie R. Groves, The Manhattan Project’s Indispensable Man, 297-299)
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