the saw-gill is very effective, it somewhat injures the quality of the cotton by tearing the fibres; to prevent this the comb-gin has been introduced (perspective, pl. 35, fig. 3; vertical section, fig. i). In Figure r, A represents a cylinder covered with rough leather which rotates in the direction of the arrow and carries with it the fibres of raw cotton fed to it. The blades a placed close to the periphery of the cylinder retain the seeds, which, liberated from the bundles of fibres by two blades (b b') oscillating rapidly up and clown, fall between the rods of the grate (i). The blades b b' are fastened to the ends of the levers c, and from a shaft placed in the lower portion of the frame (B) receive their motion by means of two eccentrics and two eccentric-rods (D (1). The raw cotton is spread out upon an endless rotating apron running over two rolls and receiving from them a forward motion, which carries the cotton under the grooved roll h, after which it is thrown into the trough III by a toothed roll (s), and is finally pushed against the leather-covered roll A by means of the oscillating comb J. The rail a is secured to the frame F j by the screw e. The cylinder A is revolved from the driving-shaft by means of a belt and a pulley (L'). The ginned cotton is filially removed from the cylinder A by a rapidly revolving fluted roll (C).
Willo70.—The cotton is always ginned on the plantations where it is produced, and for transportation is packed in hales with the assistance of powerful presses: it therefore requires subsequent loosening at the fac tories by special machines, one of which, the so-called "willow," is shown in Figure 4. This consists of a wooden casing in which rapidly revolve two horizontal shafts provided with beating arms. These arms arc so placed that those on the one shaft pass between those on the other, and, besides, a number of stationary rods arranged in two rows in the interior of the casing correspond to the intcrspaccs between the shafts. By intro ducing the cotton taken from the bales into the interior of the casing by means of an endless feeding-apron and two feeding-rolls, the firmly com pressed masses are loosened and reduced to small bunches.
Opener.—A still more effective machine, the "opener" (pl. 35, fig. 5), performs the work by means of four drums provided with thumb-like eleva tions, which receive the cotton also front a feeding-apparatus and throw it repeatedly against rows of similar but stationary teeth. Below the drums is arranged a grate, composed of thin iron rods, through which fall all foreign bodies (sand, seed, pieces of leaves, etc.). The cotton thus loos ened and freed from the coarser contaminations passes through two sieve drums with fine meshes, from the interior of which air is constantly drawn by an exhaust-fan. The cotton, thus drawn against the periphery of these
sieve-drums, is freed front dust and very short fibres by the powerful cur rent of air. The prepared cotton is removed by an endless apron.
Balling-and-lapping Jllach e. —The most important preparatory ma chine, and one closely allied in its action to those described above, is the batting-machine (scutcher, beater, or opener), which is generally combined with an apparatus for the formation of the laps, and is known as the "tap per" (section, fig. 6). The cotton is spread upon an endless feeding apron and conveyed by two pairs of fluted rolls to a beater in the inte rior of the casing a. This beater consists of two or three steel rails con nected by several cross-arms with a shaft revolving at high speed. The rails beat in rapid succession and with great velocity upon the cotton coin ing front the feeding-rolls, thus further reducing any bunches still pres ent. Below the beater is a grate, for the escape of coarser detritus. The loosened cotton next passes to the so-called "flying-space" b, and consol idates to a flor on the periphery of the sieve-drum c, from which the air is constantly drawn. The flor is detached by the pair of rolls a' , and, being further compacted between the rolls e, f, g, h, is finally rolled together upon a large wooden bobbin to a lap. To facilitate the detachment of the flor from the sieve-drum (c) the current of air is cut off at the appro priate place by a shield firmly connected with the shaft of the sieve by means of the lever m loaded with the weight n.
Figure S shows a modified form of the batting-and-lapping machine: a designates the beater; c, the grate; b, the flying-space; e and f, two endless sieve-cloths, replacing the sieve-drum; and g, the compressing rollers, back of which is the attachment producing the laps and known as the " lapper." At k and i enter the suction-channels / and 211, which lead to a fan, and by means of which the dust is removed from the cotton. k is a receptacle for the coarser contaminations, and serves at the same time for shutting off the air from below. To be enabled, when working short cotton, to bring the effective edge of the beater as close as possible to the place where the fleece is held, the feeding-rolls are frequently replaced, as in Figure 7 (154 35), by a tray (a) and a roll (b) set with sharp points, which can be brought close to the beater carried by the arms g. This arrangement is called " tray-feeding." The external appearance of an opener and lapper is shown in perspective views in Figure 9 (i5/. 35) and Figure (p. 36).