Based on Galileo GalileiâTMs* discovery that a liquidâTMs buoyancy decreases as its temperature increases. This unique device consists of a sealed glass cylinder containing multi colored floating spheres. The spheres have different weights which rise and fall at different temperatures. Current temperature is indicated by the tag attached to the lowest of the floating spheres. Use in science classes to demonstrate GalileoâTMs principle or as an interesting and attractive way to accurately measure indoor ambient temperature anywher Note: Hanging Galileo models are marked with the Sper Scientific logo.