GRAVITATIONAL; SIFTERS. 307 



are secured two semi-cylindrical plates, P, with their convex sides upward, and with 

 their inner side edges near and upon the opposite side of the handles, B. In bearings 

 in the opposite sides of the two plates, P, revolve the journals of two cylinders, 

 Q, made of finely-perforated sheet metal or fine wire-gauze to sift the dry powder 

 poison upon the plants. 



"The sif ting-cylinders, Q, are designed to he revolved by contact with the plants. 

 The ends of the 'cylinders, Q, are provided with ring-flanges, R, to which are attached 

 the ends of a number of rods, S, to strike against the plants and revolve the said cyl- 

 inders. The rods, S, prevent the surfaces of the cylinders from being wet by moist- 

 ure from the plants, which would cause the powder to stick to them and thus clog 

 the discharge holes. 



" The two sifting-cylinders, as well as the sprinkler, project of course on each side 

 of the plow and dirtribute the poison on the two adjacent rows between which the 

 plow is drawn. 



*'In practice it is found that the weight sinks the plow too deep, and to prevent 

 this a large sliding-block is attached to the cultivator legs."— Bulletin No. 3. 



EECiPROCATiNa- Stirrer Sifters. — In these the stirrer has a back- 

 and- forth movement upon the stationary sieve face to work the powder 

 through. 



" The Willie Duster.— Mr. William T. Willie, of Brenham, Tex., has 

 obtained a patent (So. 160986, March 16, 1875) for a contrivance which 

 is but a modification of the method mentioned above of the application 

 of the poison by a man on horseback by means of two sieves fastened to 

 each end of a stick and carried across the saddle. The invention con- 

 sists of two boxes suspended on a transverse bar, and made adjustable 

 vertically and laterally according to the height of the plants and the 

 width of the rows. The poison is dusted on two rows of plants by means 

 of a system of vibrating sieves at the bottom of the boxes. The appa- 

 ratus is intended to be secured to a riding-saddle in front of the rider. 



"Plate LVIII, Fig. 4, represents a sectional view of the machine, the central figure 

 showing a detailed section of one of the sifting-boxes. 



"The letters A A designate two boxes of any suitable capacity, which are constructed 

 with two fixed selves, pp, and movable sieves, p', arranged between the fixed sieves 

 and supported upon rods, so as to slide freely when the boxes are vibrated and aid in 

 pulverizing the material, and at the same time scattering it uniformly. The upper 

 sieves, 2?, will support the bulk of the material free from the scattering sieves, p'. Each 

 box has secured to it a suspension-standard, B, having a number of holes, a, through 

 it, arranged one above another, and adapted to receive suspension-pins, h c, and allow 

 the boxes to be adjusted vertically for high or low plants. C designates a bar, from 

 which rises a guide-rod, C This bar, C, is intended to be secured by the middle of its 

 length to the saddle, and through its ends holes are made through which the stand- 

 ards, B B, are passed and sustained by means of the pins, c c. Supplemental holes are 

 made through the bar, C, to allow the boxes. A A, to be adjusted for rows of plants va- 

 rying in width. D designates a bar, the ends of which are slotted longitudinally to 

 receive the standards, B B, and at or near the middle of the length of this bar, D, a 

 hole is made to receive freely through it the rod, C. The ends of bar, D, are notched 

 at, n, and are attached to the standards, B B, by fitting these notches over the pins, h 

 &, as shown in the figures." — Bull. 3. 



Rotary- Stirrer Sifters. — With these the stirrer is rotated upon 

 .the stationary sieve-face to work the powder through. 



The J. W. Young Buster, patented (]S"o. 188219) March 6, 1877, 

 by Mr. James W. Young, formerly of Southfield, Mich., now of Saint 



