In answer to the question about models being built.I have seen photos of one built in O Scale . However the builder didn't get the angle of the rotating cone correct in the housing. The model looked wrong compared with the photos of the real thing.
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www.google.com]
If you go to this website you can view the original patents , Orange Jull filed for his Jull snow plow. ( Google Patents ) . The website also has the original patents for the rotary which he designed.
Charles