There were three Manhattan Project losses that I heard about over the last week that I thought were worth briefly commenting on. They highlight, in different ways, how the living history of the Manhattan Project is rapidly vanishing.
Erwin Hiebert had worked as a chemist at the Chicago Metallurgical Laboratory. He passed away last November, though a notice was just recently sent around. I interviewed him a few years back, though not about his bomb work (connected with doing some local Harvard history). I believe I recall him telling me he had worked with Harold Urey on diffusion research. He later became an historian of science, and this was the capacity I knew him in. He was a charming old man, very helpful, very friendly. He wasn't a major figure on the Manhattan Project, but it's sometimes worth remembering how many people were involved in the project other than the main, well-known scientists and the thousands of construction workers or miscellaneous technicians. I recently had a chance to look up just how many people working at the Met Lab — we normally only hear about the 20 or so people who worked on the pile, but at its height, there were around 2,000 people working at Chicago on the bomb, with some 750 of them doing it in a scientific (as opposed to administrative or construction) capacity.
Donald F. Hornig also recently passed away. He worked at Los Alamos during the war, and was heavily involved in the instrumentation work that was required for the implosion bomb. He was credited as the inventor of the triggered spark-gap switch (a "low-impedance switch"), which was the switch necessary to divert a high-voltage signal to the 32 detonators on the "Gadget" with a simultaneity tolerance of only nanoseconds. (A patent application for this switch had been filed in his name in late 1945; it was declassified and granted in 1976. Hornig told me he had no awareness of it being filed or granted when I talked to him a few years back.) He was also one of the last people in the "Trinity" tower before its detonation, checking the electrical connections, which proved to be a somewhat hair-raising experience. He describes his work at "Trinity" in some detail here. It's worth a read:
I think I was the last person down from the tower although there might be a little bit of argument about that. I won't go into any detail, but Oppenheimer had gotten worried about nine o'clock the night before about how easy the thing was to sabotage by anyone who really knew anything about it, and so I believe it was Kistiakowsky, Bainbridge and I who each took a turn sitting with it up on the tower. My turn came from around nine o'clock until midnight, in the midst of a violent thunder and lightning storm. You get philosophical in those circumstances. You know, either you do get hit by lightning or you don't and either way you won't know what happens.
He had many later achievements, including being LBJ's science advisor.
Lastly, the K-25 plant has been completely destroyed. The Oak Ridge facility, which had been used during and after World War II to enrich uranium via the gaseous diffusion method, was the largest factory under one roof at the time it was constructed. It had been long since shut down, and, a few years back, all but one "cell" of its building had been destroyed. A number of people had been trying to keep the cell preserved as an historic site, but it came to naught. It took only 20 minutes to permanently knock down the last piece of it, the last indication of the scale of this site.
I think this is really too bad — a completely missed opportunity. I know that there are people who have mixed feelings about preserving the Manhattan Project sites — they think that they will be used as excuses to glorify the atomic bomb. I think this is entirely misguided. These sites are ambiguous and they provoke different reactions from different people. By analogy, there can be controversy over how the Enola Gay should be presented to the public, but the answer is not to melt the Enola Gay into scrap. Destroying these sorts of legacies is a permanent act, whereas the act of interpretation is an always changing one. Erasing history is not the right response to the fact that we still disagree over it. Destroying the sites where the atomic bomb was made will not change the fact that we made the atomic bomb.
The last generation of people who worked on the first atomic bombs is passing away. The bomb still exists. We should be doing more to preserve these sites, even if they make us uncomfortable, even if we are unsure how they will be used by people in the present or the future.