My grandpa had a similar contraption; a "puzzle jug" -- he'd fill it with wine, drink some, and pass it around to his guests -- who would often tip the jug and spill. Amusingly, potheads are more likely to succeed than the general population, because it's just a carburetor.<p><a href="https://en.m.wikipedia.org/wiki/Puzzle_jug" rel="nofollow">https://en.m.wikipedia.org/wiki/Puzzle_jug</a>