The self-binding reaper, the one in most general use, consists essentially of a large trav eling wheel acting as the driving wheel, which carries the framework and about and above which are the various gearings and parts neces sary for sheafing and binding, and of a smaller ground wheel on the off side of the cutting plat form. The power is distributed from the driver to the various parts by gearing or sprocket chains. The cutting parts are very similar to those of the ordinary reaper or mower, of the serrated reciprocating knife type, driven by a Pitman rod from a crank and having the usual split fingers or guards on the bar to hold the grain while it is being cut by the sliding out of the bar. The cut grain falls upon a horizontal platform, about which is an endless canvas; the latter conveys the grain to two vertical can vases parallel to one another and moving in different directions. By these the 'grain is elevated and conveyed to the sheafing platform. The mechanism on the sheafing platform col lects the grain as it is being constantly poured upon it and separates it into sheaves; next $. binder attachment binds the sheaves and re leases them, allowing them to fall straight to the ground, or, as is now more common, upon a carrier which collects a number before de positing them in convenient lots to be shocked or stooked. In binders made without vertical canvases the crop is conveyed by the platform canvas directly to the packing arms and is then gripped by the grasper carrying the twine and tied. The sheaf is lifted by a mechanical fork or arm and placed outside the horse-walk for the next round. A few years ago five-foot cuts were common with six-foot cut machines a close second. At the present time, however, seven-foot cut machines are in highest favor, and there are also a large number of eight-foot cut machines at work. The eight-foot cut is a four-horse machine and it is advisable to put this number to a seven-foot binder. If one has as much as 30 acres of grain to harvest each year, the eight-foot machine will be found economical.
Some writers have claimed that the self binder is not profitable on a farm where less than 30 acres of grain are grown annually, although they admit that during the average life of these machines they will reap and bind about 2,000 acres. In actual practice, however, it is demonstrated every season that a self binder is profitable, other things being equal, cn a farm where 10 or more acres of grain are harvested yearly. Progressive farmers usually approach the hinder proposition as follows: An initial investment of $125 at least for a three horse self-binder; interest on this investment at 6 per cent; depredation and repairs, 10 per cent: thus cost of binder, $125; annual interest at 6 per cent, $7.50; depreciation and repairs,
10 per cent, $12.50. According to this esti mate the annual cost of the binder is $20, or $2 per acre for reaping and binding 10 acres of grain, exclusive of the cost of binder twine, man, horse or tractor labor. If more than 10 acres are to be reaped the corresponding cost per acre is lower and the greater the number of days the binder is at work the greater the return on the investment. To secure the latter it is not uncommon for a farmer owning a binder to reap his neighbors' grain in addition to his own at a price running from $1.50 to $2.50 per acre, in which case the reaper invest ment may be turned into an income producer instead of a liability. Another plan becoming general in regions of small farms is for two or more adjoining landholders to purchase a reaper jointly.
In western United States and in Australia a binder is used. The machine is an adapta tion of the binder with cutter bar, 'olives, plat form and reel similar to the latter. It is pushed ahead of the team of from four to six horses and cuts a strip of from 12 to 20 feet. The ears of grain are cut off and are then raised to wagons drawn alongside the header. A com bined header and thresher is also in common use, by which the grain is cut, threshed and placed in sacks. Some of the larger types of header and thresher in use on the prairies have a capacity of 100 acres per day.
In Australia and other sections where the climate is very dry and the straw dries to brittleness, a reaper of different design is in favor. It has long comb-like teeth which strip the grain from the stalk, passing it into a mechanism which by a rubbing motion divests it of the husk and it is then winnowed, and on some large machines is ground as the har vesting proceeds.
Bibliogranhv.—Ardrey, 'American Agricul tural Implements) (Chirac-Y(1 1894) ; Casson, H. V., 'Offi cial Retrospective Exhibit of the Development of Harvest ing Machinery at the Paris Exposition, 1900' (Paris 1900) ; id., 'The Romance of the Reaper> (New York 1908) ; Davidson and Chase, 'Farm Machinery and Farm Motors' (New York 1908); Ramsower, H. C., 'Equip ment for the Farm and the Farmstead' (Boston 1917); Scott, 'Textbook .of Farm Engineering) (London 1885); Shearer, I., 'Farm Mechan ics' (1915); Swift, 'Who Invented the Reaper?' cago 1895) ; United States Department of Agriculture, Farmers' Bulletins Nos. 303 and 313 (Wash ington 1913-14).
REAR (from old French arere, modern arriire, medixyal Latin ad retro, to the back, 1,ackward), the hinderpart, or the part that comes last in order, of anything. A particular military or naval term as opposed to «van» abbreviated from vanguard, derived from the French avant, in front.