Show to manufacture optical glass the manufacture of american optical glass Is about to be inaugurated on a commercial basis a large factory having been erected by an optical firm of rochester N Y which it Is said will be equipped to make all kinds of lenses from the tiny glass used in the microscope to that of the searchlight measuring several feet in diameter the first effort in this direction was made about twenty five years ago and the effort was a failure and was abandoned the latest effort in thu the manufacture of this glass was begun experimentally by the rochester firm a few years ago and when the war broke out this had just demonstrated its success so that its expansion would have come along in the regular order of things but the necessity tor for a plant of this kind in this country has forcibly demonstrated by the war which has completely cut off the supply of optical glass which came heretofore from one or the other of the belligerent countries |