The method described reveals the level of liquid within the container. There is a distinct difference above and below.
Comment on Perfect posture
TinyShonk@lemmy.world 2 months agoHow does that tell how much fuel is left?
homesnatch@lemm.ee 2 months ago
gnu@lemmy.zip 2 months ago
You pour a bit of boiling water down the side of the cylinder then run your hand down where you poured the water - you will feel a clear delineation in the temperature at the level of the liquid gas inside.