Dual scale thermometers have colorful spheres that rise and fall to indicate temperature
- Hand-crafted thermometers
- Non-mercury liquid
Colorful glass thermometer is based on Galileo’s theory developed over 400 years ago: in liquid, a body of fixed mass becomes less buoyant as the liquid temperature rises, and more buoyant as the temperature decreases—due to changes in liquid density. As temperature changes, the multi-colored balls rise and fall within the liquid-filled thermostatic tube. Lowest sphere in the top group within the instrument indicates ambient temperature.