Re: The elevator did it
It is easy to demonstrate the explosive nature of flour. Take a six foot length of 4" PVC pipe. Drill four 3/4" holes around the circumference of one end, about 2" from that end. Place a votive candle on the ground, and put the pipe over it. Light the candle through one of the holes. Dump a scant 1.5 tablespoons (10g) of sifted[0] flour into the open end. On a calm day, the minor explosion[1] can be fairly loud, and the resulting smoke-ring can rise & expand far more than you might think. All sizes are approximate. I've never actually measured anything when doing this, yet it always works despite my lack of care and attention.
NOTE! While I've never had an issue playing with this toy, nor have I ever heard of anybody getting hurt or doing damage to anything, this may be illegal in your jurisdiction. Most such toys tend to get lawmakers upset, probably because they are always vaguely afraid that somebody, somewhere, is having fun. Needless to say, children LOVE it :-)
[0] If you don't sift the flour, it might fall as a clump & extinguish the candle.
[1] Depending on pipe size, hole size & number, the grind of flour, the quantity of flour how well it is dispersed, and other variations, the noise can range from a mild "pop" to a dull "thud" to a deep "bang". Experiment. That's what science is for, right?
Biting the hand that feeds IT
