The Courrières mine disaster, the worst mining accident in European history, killed 1,099 miners in Northern France. It is generally agreed that the majority of the deaths and destruction were caused by an explosion of dust which swept through the mine, however, it has never been ascertained what caused the coal dust to ignite in the first place. A group of thirteen survivors, later known as the rescapés, was found by rescuers twenty days after the explosion. How had they survived? Discuss