(under the class definition) Apparatus wherein the impeller comprises (1) a fluid reactive device which is asymmetrical relative to a plane, such as a plurality of blades* unequally spaced about a rotary carrier* or (2) a plurality of working members* which differ in size, shape or orientation.
(1) Note. Included under (2) above are working members merely fixed in differing operative positions (i.e., pitch).
