The Hartley Pit Disaster, Northumberland 1862. A poster describing the beam of an engine used to pump water from a mine which broke and fell down the shaft, trapping the workers inside. It took six days for the debris to be removed, by which time all of the 199 men underground had died from asphyxiation. The event devastated the local close knit community. It led, within the year, to both the forming of the Miners Permanent Relief Fund and the passing of an Act of Parliament which made it law for all mines to have two shafts to enable both rescue and ventilation in the event of an accident in one.
The poster is a family heirloom. (My great great grandfather was William Shields, a master shaft sinker and one of the named rescue party.)
It comments on how reliant mining communities were on the mines and their owners; how safety reform came after the disaster rather than preceding it; how safety and profit contend for funding and the Victorians' almost hubristic faith in technology.