Dr. Weimer served in the Natural Sciences Division at Manchester College and while still on the faculty at Manchester went to do chemical research for the Monsanto Chemical company in Dayton, Ohio. This was 1943 and the era of Hitler and the Second World War. The Nazis were thought to be developing an atomic bomb and the United States wanted to build an atomic weapon before Germany or Japan was able to do so. The Manhattan Engineer District (later known as the Manhattan Project) was organized in June of 1942 for this purpose. Monsanto Chemical Company in Dayton, Ohio was one of the participates. Forty years later Mrs. Weimer recollected, "Harry received still another call...Would you participate in a government-sponsored program involving a totally new field of science with no questions asked or answers given?" Polonium-210 was the heart of a device placed inside the atomic bomb to "initiate" the chain reaction. It was essentially the trigger that started the explosion. The trigger for the atom bomb was invented and fabricated in Dayton, by the scientists of the Dayton project. As the project neared completion Dr. Weimer became more disturbed. He once came home "and literally walked the floor all night long. Exhausted by morning he picked up a cup of coffee and remarked, 'We have succeeded, but I wish to God we hadn't. It's awful, but it has to be.'" He resigned the Project. He was invited to White Sands to observe the test of the atom bomb using the trigger, but he didn't go. He was invited to Bikini to see another test and he didn't go. In March of 1945 the trustees promoted Weimer to full professor and it was announced that "he will return to teach in the department next year." Harry did return to Manchester to teach after a two year leave of absence. He wanted others to know about what he had helped develop. Without revealing technical secrets, within a month after school began in 1945 he spoke to the Science Club on "The History and Development of the Atomic Bomb." (from William Eberly's book, The Story of the Natural Sciences at Manchester College, pg., 90 - 92) | 
