Group of six items signed by Manhattan Project chemical engineer Meyer Steinberg and Trinity Site worker Felix DePaula, including: an ALS, signed "Meyer Steinberg, U.S. Army, Special Engineer, Detachment," one page, March 10, 2018, in part: "I worked as a Chemical Engineer in the U.S. Army Special Engineer Detachment first at Oak Ridge, Tenn. on the gaseous Diffusion Plant producing Uranium-235 which was used in the Little Boy atomic bomb to destroy Hiroshima in Japan. Then I also worked at Los Alamos where we produced plutonium-239 which was used in the Fatman atomic bomb to destroy Nagasaki on July 9, 1945"; an ALS, signed "Felix A. DePaula," one page, in part: "All I did for nine months at Trinity was a helper for all the soldiers who has trade experience. Plumbers, carpenters, electrical etc. The most amazing thing I saw at Trinity site was the detonation of the first atomic bomb…I was just 18 yrs old. I knew of anything dangerous until after the detonation of the bomb. We were told to stay out of the bomb site due to contamination." Also includes four laserprint photos, 8.5 x 11 and 11 x 8.5, of the Oak Ridge and Los Alamos plants, as well as of Steinberg and other researches, each photo signed and annotated by Steinberg in black ballpoint. In overall fine condition.