This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1884 edition. Excerpt: ... board D (Fig. 32), which receives all that is shaken from the straw, and the board D1, which receives all the grain, &c, which has dropped through the concave, receive their motion from the crank T, which also gives motion to the wood riddle E. These boards and the riddle E are connected, so that their motions are simultaneous. The rod by which they are connected with the crank T is fixed under the board D1, and is thinned or flattened near the point of its fixture; being thus made flexible it needs no joint. The riddle surface, which is usually constructed of mahogany or walnut, is grooved in the direction of the length of the machine, the grooves being of 1 in. pitch, and the holes of different sizes from J in. to i in., the smallest sizes are for such grain as wheat and rye. These parts are suspended by hangers v u, which are firmly fixed at either end and consist of thin strips, usually of tough ash. The board F and the other parts of the lower shoe are suspended by similar hangers (Fig. 32). The shoe also receives its motion from crank T, and is connected therewith by a flexible rod as shown in Fig. 32. When threshing oats the seed-sieve at w is taken out and a blank plate put into its place, but the seedsieve is left in for threshing wheat and barley. The sieves G and G1 vary in mesh from J in. to J in. according to the grain being threshed. The strength of the blast through and past these sieves is regulated by a slide shown near I (Fig. 32). This blast must be regulated with great care, so that all the grain, including the light grain and chobs, may drop within the bar z, while the chaff from the upper sieve must be carried beyond that bar. The construction of the fan H is sufficiently shown in the section (Fig. 32). The...