This ancient thermometer was invented by Galileo Galilee (1564-1642), who was an Italian mathematician, physicist, astronomer and inventor.
It not only can show the temperature, but also be artistic.
How it works: This is a replica of Galileo’s thermometer based on his discovery that the density of liquids changes as temperature varies. Each of the glass balls is exactly weighted by partially filled the spheres with liquid. When the temperature rises, the liquid in the glass cylinder becomes less dense and the balls sink slowly to the bottom.
How to read it: The lowest temperature ball within the group at the top of the thermometer tell the correct temperature.