Based on Galileo Galileis discovery that a liquids 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 silver tag attached to the lowest of the floating spheres. Use in science classes to demonstrate Galileo's principle or as an interesting and attractive way to accurately measure indoor ambient temperature anywhere.Note:To preserve the function and appearance of this product, the Galileo thermometer should not be left out in direct sunlight.