Lecturer: “Now, this compound is both neurotoxic and mutagenic before it sets; it still is when it’s set, but as long as you don’t eat it you should be fine. For this reason, I recommend checking for solidity by shaking the tray from side to side to see if it’s still sloshing rather than tilting the tray to see if it falls out, for reasons I hope are obvious. On you go.”

(Several minutes pass. I am tapping the tray, and notice the sloshing is turning into a wobble.)

Me: “Oh, hey, I think ours is nearly done!”

Lab Partner: “Really?”

(The lab partner proceeds to tilt the tray upwards. My assessment is correct, and we get bits of partially-congealed solid all over our desk. I grab my lab-partner back before she gets any on herself. The lecturer comes over to investigate, and I explain the situation.)

Lecturer: “Well, you’re doing better than me, at any rate. My first lab partner tried to check if it was done by dipping his finger in to see if it was solid, and then licked it clean. He got carted out in a stretcher.”

Me: “Uh…”

Lecturer: “The scary thing is he now works as head of [regional division of bank].”