Ola, my question is a rather simple one, I suppose. I have collected Galileo Thermometers for decades and have a question regarding the liquid.

Some of the older thermometers were filled with mercury which was dangerous if it came in contact with your skin. So, do some research on mercury filled thermometers & see what you find. I’m not sure that you can even buy mercury replacements anymore, so you may need to replace with a water filled one. Maybe this will give you enough info to guide you in the needed direction!!!

Thanks for all your info. As I have stated, I have worn out my sources of water. And I have also talked with our maintenance engineer, and he said it is not water. We have tested every water available to man, and the little bulbs simply float. They will not sink. I will explore to find a source of liquid and a new container. Thanks everyone. Have a great day or night, whichever.

Oh, and just an aside: this one just simply cracked or something? It hasn’t been moved in nearly four years, other than to dust around it and clean it off. The crack happened during the night. I was asleep, and I know I don’t sleep walk. Thanks again.

Maybe you can try ethanol: https://science.howstuffworks.com/how-does-a-galileo-thermometer-work.htm#:~:text=What%20is%20the%20clear%20liquid,even%20more%20so%20than%20water.

@LadyMarissa
Galileo thermometers have no mercury.

@ThomRicTucker21
According to the Wikipedia article, the composition of the fluid is not important. Thought it must be lighter than water. So water diluted with alcohol works.

The sealed floats can be identical. Their varying flotation is adjusted with weights.