The disaster at Hartley killed 204 men and boys, trapped underground by a falling beam and with no means of escape.The Hartley Disaster provoked a media storm unlike any previous mining disaster. The harrowing scenes were reported over several weeks in national newspapers. A public outcry resulted after it was revealed that the disaster could have been prevented if those trapped underground had a second way out. After a fight with members of the coal owning Lords, an amendment to the Coal Mines Act was brought in and after 1st January 1865 it became unlawful for a mine owner to work a mine unless there were at least two means of egress. The provisions in the act were adopted in the mines of the Empire and later to all legally operated mines across the globe. Memorial glasses are particular to North East England and were originally intended to serve as a reminder to families of those who had died. This glass also stands today as a reminder of the many lives across the world saved as a result of the changes made following the disaster.




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There is lot more about the "disaster Glasses" in a book called "An alarming accident". Which tells the story's behind the glasses.
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