WGSCG112 Galileo Thermometer 8.25 H $31.50 Item is as shown, no personalization included.
Searching for a way to measure temperatures, Galileo discovered this fascinating method. He placed several exactly weighted balls in a cylinder filled with a liquid. He found that the balls rose or fell according to the temperature. By this method, Galileo was able to determine the current temperature. The thermometer works on the principle that the density of a liquid changes as temperature varies. Each of the glass balls is exactly weighted by partially filling them with liquid. When the temperature rises, the liquid in the glass cylinder becomes less dense, and the heavier balls sink slowly to the bottom. You read the thermometer by looking at the lowest floating ball, which indicates the current temperature. If all of the balls float to the top, the temperature is below the lowest floating ball. If all the balls sink, the temperature is above the highest ball.