The Manhattan Project was formed in June 1942 under the overall control of Army Maj. Gen. Leslie Groves. The project was given overall responsibility for designing and building an atomic bomb, a race at the time to beat the Germans, who were rumored of building their own bomb. Under the Manhattan Project three large facilities were constructed. At Oak Ridge, Tennessee huge gas diffusion and electromagnetic process plants were built to separate uranium 235 from the more common form, uranium 238. Hanford, Washington, became the home for nuclear reactors which produced a new element called plutonium. Both uranium 235 and plutonium are fissionable and can be used to produce an atomic explosion. Los Alamos National Lab was established in northern New Mexico with a primary purpose of designing and building the bomb. At Los Alamos many of the greatest scientific minds of the day labored over the theory and actual construction of the device. The group was led by Dr. J. Robert Oppenheimer who is credited with being the driving force behind building a workable bomb by the end of the war. In the months leading up to the first test, two designs for an atomic bomb, one using uranium 235 and another using plutonium were being built. The uranium bomb was a simple design and scientists were confident it would work without testing. The plutonium bomb was more complex and worked by compressing the plutonium into a critical mass to sustain a chain-reaction. The compression of the plutonium ball was to be accomplished by surrounding it with lense-shaped charges of conventional explosives. They were designed to all explode at the same instant. The force would be directed inward, thus smashing the plutonium from all sides. In an atomic explosion, a chain reaction picks up speed as atoms split, releasing neutrons plus great amounts of energy. The escaping neutrons strike and split more atoms, thus releasing still more neutrons and energy. In a nuclear explosion this all occurs in a millionth of a second with billions of atoms being split. The scientists weren't sure if the conventional explosive, TNT (Trinitrotoluene), would trigger the chain-reaction of the plutonium. In case it would fail to occur, the TNT would blow the very rare and dangerous plutonium all over the countryside. Thus Jumbo was built, with the idea that Jumbo could withstand the conventional TNT explosion and contain the plutonium, in case of a failure. Jumbo was designed and manufactured by Babcock and Wilcox in Ohio. It was originally 25 feet long, 10 feet in diameter and weighed 214 tons. It was transported by rail to Pope, New Mexico, and from there by a specially built, 64 wheel flatbed, to the Trinity Site. As they approached the proposed test date, the scientists became more confident that the device would work, and Jumbo was not used. Instead, Jumbo was placed under a steel tower 800 yards from ground zero. The tower melted, but Jumbo was intact. Today Jumbo rests at the entrance to ground zero so all can see it. The ends are missing because in 1946 the Army detonated eight 500-pound bombs inside it. Because Jumbo was standing on end, the bombs were stacked in the bottom and the asymmetry of the explosion blew the ends off. (Source: Pamphlet available on site). This picture was taken on 7 October 2017, Sig...