Science and Mechanics 1936-06.jpg Science and Mechanics 1936-05ThumbnailsScience and Mechanics 1936-08Science and Mechanics 1936-05ThumbnailsScience and Mechanics 1936-08Science and Mechanics 1936-05ThumbnailsScience and Mechanics 1936-08

New Dornier rotor-wing flier, an early helicopter design.



Artist: Frank R. Paul

Source: eBay seller banjoflier