The Model 40B-4 was designed to carry four passengers and a substantial load of mail. Pacific Air Transport used theirs on Contract Airmail route C.A.M.8 between Seattle and Los Angeles. The pilot sat in an open cockpit just ahead of the circular "Boeing System" insignia. From Boeing 60 years ago.
This photo was added on 13 September 2017, and has since been viewed 167 times.