Cool little things these hand boilers, or love meters if you prefer. Its basically a tool that demonstrates vapour-liquid equilibrium. People collect these little glass sculptures and use them as a way to measure love.
These hand boilers were sometimes known as love meters because the pipes that separate the two top and bottom glass chambers are twisted into a heart shape and the liquid inside is red. A couple would hold a chamber each and which ever forced the liquid through to the other end would be the more passionate of the two.
Us humans did a lot of silly things like that back when we had nothing better to do. These days they are scientific novelties which can be found on the desk of your child’s science teacher. Click Mechanics of a hand boiler to learn more about how it works.
You can see the hand boiler working in my video below. This particular hand boiler magically jumped from my sons hand to the floor and smashed into a million pieces. He swears it grew legs and sky dived out of his hand.
If you want one click Hand Boiler from Aliexpress