Pan American Airways System Boeing 314 NX18602 (NC18602) “California Clipper” at Puget Sound, Washington, USA. The “X” in the registration number pictured on its tail would indicate this image is pre-delivery and still in the test flight phase. The “California Clipper” was delivered to the fleet in 1939.

Close-up of bookmark sticking up from book I was reading at the time picture was taken.