Robert Oppenheimer: Fine Gray Felt Stetson Hat Which Belonged To the Famed Physicist and Father of the Atomic Bomb.  The hat is accompanied by a 1958 letter of transmittal on his official Assistant Secretary of State letterhead from Andrew H. Berding. It was being sent to a "Timmy," who was apparently recovering from an illness. Berding wrote: "I have today sent to you by messenger a grey Stetson hat which belonged to Mr. Robert Oppenheimer. Mr. Dulles (then Secretary of State) informed me that you would like such a thing and I am more than pleased to present it to you. When I next see you I will tell you the story of how he gave me this hat after a 'top secret' briefing." The hat had been signed by Oppenheimer on the leather sweatband inside. When it was purchased by the previous owner at auction in 1993, it was noted that the signature had faded, but was still visible. Unfortunately it has continued to fade over the ensuing years, so now all that remains is a faint hint of the original signature. Nonetheless, this is an interesting personal possession from one of the most important scientists of the 20th century.