Thanks for sharing that memento.
Most of the people who signed in at 109 East Palace Avenue probably had no idea regarding the nature of the project they had been recruited to work on. Even after they arrived at Los Alamos, many of them were not told. I suspect some of them guessed, but others only learned about the atomic bomb when its existence was revealed to the public at large. One of my college professors, a refugee from Hungary who had been identified in elementary school as a math(s) prodigy, was among those who was never formally told why he was assigned to spend ten hours a day solving differential equations. Los Alamos was one of a number of installations that contributed to the "Manhattan Project." It was an enormous undertaking. The secrecy wasn't perfect, but apparently nothing ever leaked to any of the Axis powers.
