Very Rare Froment Principle 12" Desk Fan. This Very Rare Fan Was Acquired From A Swiss Collector And Possibly The Only Known Example. Paul-Gustay Froment (1815-1865) Was A French Engineer Who Devised A Number Of Scientific Instruments. In 1844 He Devised An Electric Motor That Was One Of The First Used For Industrial Purposes. In His Design, Electromagnets Are Energized To Pull In Iron Bars Mounted On A Rotating Cage. Once The Iron Bar Is Level With The Electromagnet, The Current Is Cut Off Until The Next Iron Bar Is In Range. A Commutator Is Used To Complete And The Break The Current To The Electromagnet. 

Dimensions:

Height: 13.5"

Width:11"

Depth:7.5"