Vintage Marine Engine Valve & Propeller Motion Demonstrator by Clarence E. Long bike path the long-time provider of sanitary

the long-time provider of sanitary napkins and other menstrual products

this appears to be a simple framed print

Vintage lighted advertising clock

The mounts of the sconces measure 4

Vintage Marine Engine Valve & Propeller Motion Demonstrator by Clarence E. Long bike path the long-time provider of sanitaryc. 1930s; Clarence E. Long Marine Engineering School Milwaukee, Wisconsin Mechanical marine engineering demonstrator constructed as an instructional display to illustrate the relationship between propeller rotation and internal valve or linkage motion. Mounted on a painted wooden backboard with integrated base and carry handle, the piece features a brass and steel linkage assembly connected to a small metal propeller. Turning the propeller drives the