David S. Mackey, and Jarvis R. Smith, of Batavia, N. Y, have made certain improvements in machines tor extracting the smut and other impurities from grain, for which measures have been taken to secure a patent. The improvement may be briefly described as follows:—Two circular plates or discs are placed within a cylinder both nearly horizontal with each other, one of which revolves rapidly and the other remains stationary.— These plates or discs are each provided with two or more concentric inclined flanges having radial flutes or grooves cut in them for the purpose of thoroughly scouring and separating the smut and other impurities trom the grpin These discs, made slightly concave, are sur rounded by a curb, which collects and concentrates the grain. The whole is very con veniently arranged.