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Show GLASS-MAKING BY MACHINERY Inventors Were Long In Perfecting Process, But Their Persistency Has Overcome All Obstacles. It was only within recent years that the art of making window glass by machinery ma-chinery was mastered, the old crude hand methods which had been the only means known for hundreds of years dying hard and slowly. Inventors Inven-tors and skilled mechanics found all their efforts resisted, not so much because be-cause of any particular opposition on the part of the hand-workers, but because be-cause they were unable to perfect the correct form of machinery for their purpose. Even now a considerable quantity of window glass is still hand made, but machinery is everywhere displacing the I process. Until about twenty years ago a man with a blowpipe blow-pipe represented the only method of producing window glass, and the sheets were limited to about two feet by three feet, even then containing defects which could not be avoided. By. the perfecting of the cylinder and sheet-drawing process it has recently become possible to manufacture glass of good quality and beautiful clarity in. about the same manner that paper Is made that is, in a continuous sheet. Machinery does everything, taking the glass from the molten mass in the furnace, fur-nace, handling it automatically through all its changes until it is delivered on a table, ready to be washed, cut and boxed for shipment. These machine-made machine-made sheets have already been made as large as five feet wide by ten feet long, and apparently the size is limited only by the size of the machine. The first commercial factory for making continuous sheet drawn window glass j was built in Pennsylvania in 1907. j |