When I was a kid, I put some carbide in an Erlenmeyer flask with a two-hole stopper. Thistle tube down one hole, glass jet tube coming out the other hole.
Poured in water, watched the reaction, lit the gas coming out of the jet tube.
Expected a smoky flame, but noooo. Flame slowly proceeded back down the glass tube since the velocity of gas coming out was a little slower than the flame front going in.
Watched flame go around the corner of the jet tube and realized what was happening.
BANG!
Had got up from chair and covered face just in time. Thistle tube stuck in Celotex ceiling, glass all over the place.
Only got a nick of glass in my pinky.
Couldn't call it smart luck, must've been dumb luck.
Never trusted acetylene again.
--Anonymous fool