This photo was taken at S Site in Los Alamos where explosive testing was carried out to perfect the "implosion" process.  The man on the left, partly obscured, is Morris Patapof, the civilian group leader.  The other two men are SED's - Man in middle is unknown and Monroe Messinger is on right.  The wall behind Monroe is fortified; the charges on which they were working were detonated in the area where the picture was taken.  This photo courtesy of Monroe & Esther Messinger.  If anyone recognizes the man in the middle, above, please contact us via "feedback".