In the ordinary process, which is by far the most commonly used, the sliver from the card is put through successive similar operations, known as drawing, the object of which is to draw out the fibres and cause them to lie parallel to each other. Six card slivers are fed together between two pairs of rollers, the second of which is revolving faster than the first. The obvious result of this is the stretching of that portion of the slivers which is between the two sets of rollers. The operation is usually performed two or three times, in each case combining six strands into one. The sliver delivered by the third drawing machine will be of the same diameter as the original card sliver, but will contain more or less parallel fibres. [Illustration: _Roving Frame_] [Sidenote: _Roving Operations_] [Sidenote: _Slubber_] There remains now only one series of operations before the yarn is ready to be spun. The sliver must be reduced in size and given a certain amount of twist; these objects are accomplished by the roving frames, of which there are either three or four. The first, or slubber, passes the drawn sliver through rollers without combining, and winds it up on bobbins set in spindles. The sliver is twisted by being fed onto the bobbin by an arm, or flyer, which revolves a little more slowly than the spindle, being drawn around after it. The result is a slightly twisted sliver, now called a roving, about the diameter of a clothes-line. [Illustration: _Four Stages of Roving_] The intermediate, fine frame, and jack frame,—or, if there are only three roving boxes, the intermediate and fine frames,—combine two rovings into one of smaller size and more twist. The mechanism is much the same, except that in each successive frame the spindles are smaller and revolve faster, until finally the thread is small enough to spin. [Sidenote: _Second Process_] [Sidenote: _Lapper_] Where it is desired to spin special kinds or very fine yarns twenty card slivers are usually combined in a machine similar to a drawing frame and known as a sliver-lapper. The twenty ends are drawn between rollers and delivered not as we should expect in one strand, but in a narrow band or lap, which is wound on spools. Four of these laps are again combined and drawn over a spiral surface in the ribbon lapper which delivers its product to the comb. The cotton is now in a band less than a foot wide, with fibres more or less parallel and practically clean. Since it is desired to spin a yarn which demands not only parallel but uniform fibres, the short fibres must be eliminated. [Sidenote: _The Comb_]