…of How Not To Do It at In The Pipeline, featuring water aspirators to produce light vacuum in the chemistry lab. I remember using these in high school, I think, but I'm sure Mr. D. never suggested that we run a tube all the way down the drain.
Well, one day, one of the guys in the lab next door to me was shocked to see water blasting around in his hood. It was a real fountain, just geysering out full blast from what must have been a cracked water line or something in the back. He ran over and immediately shut off every tap – but to no avail. Roaring, showering water everywhere. Getting a look at the source, he realized, to his consternation, that the water was coming up out of the drain in the back of his hood. I remember standing there with him, staring at this in disbelief. It looked like a special effect. How on earth could you get water blasting up out of a drain pipe?