Reaper. A reaper is a farm implement or person that reaps crops at harvest when they are ripe.
   Usually the crop involved is a cereal grass. The first documented reaping machines were Gallic reaper that was used in modern-day France during Roman times.
   The Gallic reaper involved a comb which collected the heads, with an operator knocking the grain into a box for later threshing. Most modern mechanical reapers cut the grass; most also gather it, either by windrowing it or picking it up. Modern machines that not only cut and gather the grass but also thresh its seeds, winnow the grain, and deliver it to a truck or wagon it are called combine harvesters or simply combines; they are the engineering descendants of earlier reapers.
   Hay is harvested somewhat differently from grain; in modern haymaking, the machine that cuts the grass is called a hay mower or, if integrated with a conditioner, a mower-conditioner. As a manual task, cutting of both grain and hay may be called reaping, involving scythes, sickles, and cradles, followed by differing downstream steps.
   Traditionally all such cutting could be called reaping, although a distinction between reaping of grain grasses and mowing of hay grasses has long existed; it was only after a decade of attempts at combined grain reaper/hay mower machines that designers of mechanical implements began resigning them to separate classes. Mechanical reape
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