Lighting has played a critical role in the safety of underground coal and metal mining for several thousand years. Challenges in an underground mine environment include dust, confined spaces, surfaces ...
The Canadian Press on MSN
Today-History-Dec17
Today in History for Dec. 17: In 1538, England's King Henry VIII was excommunicated by Pope Paul III. Married and divorced several times, Henry declared himself head of the Church of England. In 1777, ...
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