Vintage glossy 7.25 x 6.75 photo of de Forest holding his 3-electrode vacuum tube, signed and inscribed in fountain pen, “Cordial regards to Mr. & Mrs. Merkel, Lee de Forest, Sept/35.” Photo is affixed by its top edge to a slightly larger piece of cardstock. In very good condition, with trimmed edges, some light creases and ripples, and a small area of surface loss along top edge. RR Auction COA.
