Page:The New International Encyclopædia 1st ed. v. 19.djvu/301

* THRESHING. 255 THRIFT. flints fastened to the lower side, in place of rollers. The primitive implement in Northern Europe was the stick, and ;in improved modifica- tion of it, the flail, is still used to a limited ex- tent in Europe and America. The flail consists of two sticks loosely fastened together at one end by stout thongs; one stick is used as a handle by the workman, and by a circular swing around his head he brings down the other stick hori- zontally on the heads of the loosened sheaves spread out on the barn-floor. Early but unsuccessful inventions to supersede the flail by a machine, both in England and Amer- ica, were largely of the rotary beater or flail type. In 1786, however, Andrew Jleikle, an ingenious Scotch mechanic, produced a threshing machine so perfect that, despite nearly a century of im- provers, it is essentially the machine of its in- ventor. In Jleikle's machine the mode of opera- tion is as follows: A sheaf is loosened and spread out on the feeding-board, with the ears toward the machine; it is then pushed forward till caught between two revolving fluted rollers of cast iron, a new sheaf taking its place as soon as the first has disappeared. Behind the rollers is a rapidly revolving drum or cylinder, having four beaters or spars of wood armed with iron placed along its surface parallel to its axle ; and these beaters, striking the heads as they are pro- truded from between the rollers, detach the seeds and husks. Grain and straw then pass together over the cylinder, the grain falling through wire- work, the straw being passed forward by circular rakes, which thoroughly toss and separate grain and chaff and then eject the straw. The grain which has fallen through the wirework is re- LiONQITTTDINAI. eECTION OF MODERN THRBBHEB. ceived into a winnowing machine, where the chaff is blown out, etc., and is then either discharged or, as in the most improved machines, is raised by a series of buckets fixed on an endless web, and again winnowed, to separate the perfect grains from the light and small seeds. Previous to the second winnowing, barley is subjected to the process of hummeling, by which the awns are removed. ^Modifications of Meikle's drum in which the two grooved cylinders were dispensed with were employed to some extent in threshing machines in England and America, but have been almost entirely superseded in modern machines by a high-speed cylinder with radial teeth playing between inwardly projecting teeth set in a fixed concave or section of a cylinder. Prior to 1840 little progress was made in perfecting the thresh- ing machine in .merica. Since that date im- provement has been rapid, and the modern .Ameri- can machine with a capacity of 1000 bushels per day is a marvel of ingenuity and efficiency. In its most advanced form it cuts the bands of the sheaves and feeds itself; thorouglily separates the grain from the straw, winnows the grain and deposits it in sacks or loads it into wagons ; re- moves the straw and stacks it. The figure shows the interior construction of a modern thresher. The concave is open and has in rear an open grate so that the larger part of the grain is separated from the straw at this point and is conveyed di- rectly to the fan. A considerable i)ortion, how- ever, still remains in the straw and can lie sepa- rated only by further agitation, which is secured by the vibrating separator, revolving pickers or beaters, and shaking forks shown in the centre of the machine to the rear of the cylinder. These devices beat the straw thoroughly, at the same time conveying it to the rear of the machine, where it is taken by the stacker, which consists either of an elevator or tul^e with blast. The separated grain drops through the perforated bottom of the separator and with the grain com- ing directly from the drum is carried to the fan- ning mill by means of a vibrating platform or conveyor located immediately beneath the sepa- rator. The parts of the modern thresher are in large measure adjustable, so that the machine may be adapted to different kinds of grain and to a variety of conditions, but separate piachines for special purposes are also made, as, for in- stance, for threshing rice, peas and beans, pea- nuts, clover, and for husking maize and shredding the fodder. Inventive genius is also being large- ly exercised in de- vising ingenious accessories to the thresher proper, such as automatic band cutters and feeders, stackers, and grain meas- urers and loaders. The motive power most commonly used for driving threshing machines is horse power or steam. The former was most common in the earlier da.ys of the threshing maoliine, but has been largely superseded by the portable steam-engine. Engines with straw-burn- ing furnaces have been used in Hungary and in the rice regions of the United States. THRIFT (Icel. prift, from >rifa, to thrive, clutch, grip; so called from the rapid growth of the plant), Armerin. A genus of plants of the natural order Plumbaginacefe, having the flow- ers collected into a rounded head, a funnel- shaped dry and membranous calyx, five petals united at the base, five distinct .styles, and five stamens attached to the base of the petals. By many botanists it has been regarded as a sub- division of the genus Statice, from which it is distinguished chiefly by having the flowers in heads. The common thrift {Armeria maritima) is a European seacoast plant which grows in turf-like form, with linear leaves, scapes a few inches high, and beautiful rose-colored flowers in miilsiimmer. Being hardy and easily cultivated.