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Anthracite is a compact variety of coal that was first burned as a residential heating fuel in the US by Judge Jesse Fell in Wilkes-Barre, Pennsylvania. It differs from wood in that it needs a draft from below. By burning it on an open grate in a fireplace, Fell proved that it could be a viable heating fuel. Fell's experiment took place 18 years after anthracite coal was said to have been discovered in Pennsylvania by hunter Necho Allen. According to legend, how did Allen "discover" anthracite? Discuss...
Source: Anthracite Coal First Burned as Residential Heating Fuel (1808) (http://encyclopedia.thefreedictionary.com/Anthracite)