In 1936, safety glass for spectacles passed a successful test in London, England. Pounded with a hammer, the glass was marked with myriad lines but remained intact. The shatter-proof eyeglasses are said to be especially recommended for athletes engaged in such strenuous sports as tennis, football and baseball.
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| Photo shows the shatter-proof spectacles with glass intact. Subject holds the tool with which the glass was tested. |
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