Cause of Explosion:  Blown-out shot.  The shot firers had loaded the holes, connected the leads, and signed out on the surface before the master switch was thrown to fire the shots.  Also, before the switch was thrown, they had returned underground to hasten their re-inspection of the faces required after shooting.  Gas and dust were ignited by overloaded blown-out shots or arcing lead wires as the switch was left in. Note: This mine is also referred to as Stag Canon No. 1, 2