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and the perſon expoſed to hurt his fingers. But the advantages reſulting from the raſp, ſuggeſted to me the idea of introducing it, in the conſtruction of a mill; of which I now give the deſcription.

I got a raſp made with Swediſh fheet iron, to which I gave a cylindric form(ig. 1.) about ſeven inches diameter, and about eight inchés high; the perforations from the holes are inwards. This raſp is ſupported by three feet(AAA) made of flatted iron, ſeven inches high, and ſolidly fixed to the raſp by nails rivetted thereon. The lower end of each foot is eſbowed out about an inch, with a hole bored through to receive a ſcrew.(See the feet of the mill, Fig. 4.) One inch below the upper extremity of the tripod, there is fixed at B(Pig. 1 and 4.) a threc-branched prong of flatted iron, rivetted together, to keep the three feet firmly at their proper diſtances: the centre of this prong is perforated with a fquare aperture, to ſerve as the point of reſt to a wooden or iron axle-tree; of which we fhall ſpeak preſently. To the upper part of the cylindric raſp is added a kind of hopper(CC, Fig. 4.) of fheet iron, about ten inches diameter, and five inches high. In the inſide of the cylindrical raſp, a ſecond raſp is fixed, but of a conic form(Fig. 2 and 3.) the point of which is truncated: this raſp fhould be of ſtrong ſhect iron, and the projection of the apertures are to be outwards. This cène is placed with its baſe downwards, as may be ſeen(Eig. 4.): at the upper part of the cone a ſmall triangular ſtar, or prong of threc branches, is rivetted at BBB(Pig. 2.) of flat iron. In the middle, a ſquare aperture is made to receive a wooden or iron axle-tree; but to give greater reſiſtance to this part of the cone, it is ſtrengthened by an iron cap fixed on the raſp and rivetted with nails, and likewiſe bored with a ſquare hole for the axis to paſs through..

Fig. 3. repreſents the ſame cone ſeen in front; the baſe(CCC) is alſo furniſhed with a ſtar of three branches, rivetted by three points to an iron hoop, placed at the lower part of the inſide of the cone. The centre of this ſtar is alſo pierced with a fquare hole for the paſſage of the axis.

Fig. 5. is the axle-tree; it is an iron bar ſixteen inches long, about ſeven inches ſquare, round at the bottom, and alſo round at top. where it correſponds with the ſtar GGG(Fig. 7.) in order to turn on its two points of reſt; and it is made fquare at the upper end to receive a handle about nine inches long, with which the conic raſp is turned. At D(Fig. 54) a fmall hole is made to receive a ſmall raſp E, in order to fix the conic raſp on a level with the cylindric raſp.—

Eig. 6. is a wooden veſſel, in the fhape of a bathing-tub, wherein the mill is fixed, and repreſented with a bird's eye view. AB Ois an iron ſtar of three branches, and ſcrewed on the tub. The centre of this ſtar is pierced

with a round hole, to form the centre of gravity for the axis when in motion.— 8

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