Steve Mould, a wizard, demonstrates the properties of this unusual potion called polyethylene oxide. It's a polymer that seems to pour itself if you tip the container over just slightly. The magical properties permit it to flow against rather than with gravity.
Polyethylene oxide is commonly used to lubricate razors. But elves and half-elves should avoid it even in this form, as it is midly toxic to them, inflicting 1 HP damage per round.