Explosions at the face of experimental coal mine shaft.
United States of America.
The U.S. bureau of Mines demonstrates the effects of a mine explosion. Spectators sitting on a hill at a safe distance.
M.S. Explosions at the face of the experimental shaft. Causes a large sheet of flame to billow out followed by a huge cloud of white smoke followed by a coal dust cloud.
Lavender & Mute.