The spindles of cop machines are gear driven as shown clearly in Fig. 26; the large skew bevel wheels are keyed to the main shaft, while the small skew bevel wheels are loose on their respective spindles. The upper face of each small skew bevel wheel forms one part of a clutch; the other part of the clutch is slidably mounted on the spindle. When the two parts of the clutch are separated, as they are when the yarn breaks or runs slack, when it is exhausted, or when the cop reaches a predetermined length, the spindle stops; but when the two parts of the clutch are in contact, the small skew bevel wheel drives the clutch, the latter rotates the spindle, and the spindle in turn draws forward the yarn from the bobbin, and in conjunction with the rapidly moving yarn guide and the inner surface of the cone imparts in rapid succession new layers on the nose of the cop, and thus the formed layers of the latter increase the length proportionately to the amount of yarn drawn on, and the partially completed cop moves slowly away from its cup or cone until the desired length is obtained when the spindle is automatically stopped and the winding for that particular spindle ceases. Cops may be made of any length and any suitable diameter; a common size for jute shuttle is 10 in. long, and 1-5/8 in. diameter, and the angle formed by the two sides of the cone is approximately 30 degrees. [Illustration: FIG 26 COP WINDING MACHINE _By permission of Messrs. Urquhart, Lindsay & Co., Ltd_.] CHAPTER XIII. WARPING, BEAMING AND DRESSING There are a few distinct methods of preparing warp threads on the weaver's beam. Stated briefly, the chief methods are-- 1. The warp is made in the form of a chain on a warping mill, and when the completed chain is removed from the mill it is transferred on to the weaver's beam. 2. The warp is made in the form of a chain on a linking machine, and then beamed on to a weaver's beam. 3. The warp yarns are wound or beamed direct from the large cylindrical "rolls" or "spools" on to a weaver's beam. 4. The warp yarns are starched, dried and beamed simultaneously on to a weaver's beam. The last method is the most extensively adapted; but we shall describe the four processes briefly, and in the order mentioned.