Random fact: flammible flour

From wikipedia:

Flour dust suspended in air is explosive, as is any mixture of a finely powdered flammable substance with air,^[1] see Lycopodium. In medieval flour mills, candles, lamps, or other sources of fire were forbidden. Some devastating and fatal explosions have occurred at flour mills, including an explosion in 1878 at the Washburn "A" Mill in Minneapolis, the largest flour mill in the United States at the time.^[2]