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An Encyclopedia of the History of Technology part 85

An Encyclopedia of the History of Technology part 85. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART FIVE TECHNOLOGY AND SOCIETY will run in a gentle circle again to help keep it close to the reed. Then the points on the shuttle must be carved so that when it is held by them the centre of gravity lies towards the back. It was probably not until after 1747 when Kay had to flee to France to escape the hostility aroused by his invention that he made the final and possibly crucial modification. On earlier shuttles the bobbin or pirn of weft was free to rotate on its spindle and the weft was pulled off from the side through a hole in the middle of the shuttle. With the faster speed of the flying shuttle and its sudden deceleration in the box the pirn would have continued to rotate causing a snarl in the weft. This fault was overcome by placing the pirn firmly on the spindle or skewer in the shuttle and drawing the weft off over one end and out through a hole at that end of the shuttle. The normal manner of winding the yarn on to the pirn was to traverse it from side to side along the face of the bobbin so that parallel layers were built up. Kay s new method was to wind the yarn in short traverses at one end of the pirn to begin with and to build these up into a cone. Then he continued winding on this short conical surface until the entire length of the pirn had been filled and he had made a cop. This method of winding was soon copied on the great spinning wheel see p. 813 because then this cop could be put straight into the shuttle without rewinding. The flying shuttle became much more popular in Lancashire after 1760 when John Kay s son Robert invented the drop box. Instead of a single box for the shuttle at the end of the slay he introduced a tiered box holding at first two but later up to four shuttles. This could slide up and down so that any shuttle could be lined up with the race. Shuttles with either different colours or different types of weft could be put on the shelves and the weaver could select which one he wanted by pressing a lever on the reed with .