SHATTERPROOF GLASS USED IN SPECTACLES (Nov, 1934)
SHATTERPROOF GLASS USED IN SPECTACLES
Hammer blows cannot shatter the glass in safety spectacles recently developed in England. Under the impact of the metal, the lenses crack as does the safety glass used in automobiles, but the broken fragments will not scatter. The glasses are designed for athletes, workers, and others who run the risk of having their spectacles struck by flying objects.