The gravity of the molten wax blobs and the oil/water/whatever surrounding medium it moves through, are close enough that it will cool enought by the time it reaches the top of the lamp away from the heat coil at the bottom, that it will fall back down.
Sorry, that should be “specific gravity” of the molten wax blobs, not “gravity”.
I’m lost. Is this supposed to be an answer to another OP?
It seems the OP disappeared but the title is self explanatory and astro answered it pretty well. I was going to say about the same thing except I did not know it was wax and I was hoing to say goo. _
Cecil on How do lava lamps work?
Heat coil? I thought it was a light bulb.
You are correct, the initial heat source is a light bulb. I should have said “radiating coil”. There is a free floating metal coil at the bottom of the glass container that picks up the bulb’s heat and evenly distributes it throughout the wax. You don’t usuallly see the coil because it is sitting inside the pool of wax at the bottom of the container.
It is. See Cecil’s column above. And be sure to only use 40 watt bulbs. Higher wattage scorches the wax and turns it into unsightly hard blobs.
Doh! Space – the final frontier. These are the voyages of the moderator manhattan.
Should figgered that one out on my own.
Carry on.
Yes very strange indeed about my original op. It just disappeared.
Anyway I now know much more than I did about lava lamps. Thanks guys!
aha
I thought the metal was to prevent the glass from cracking due to the heat.