H-B DURAC Galileo Thermometer, 18 to 30C 64 to 88F, 7 Spheres, 17in

Galileo galilei discovered when a liquid's temperature increases, its density decreases. His findings inspired these unusual and interesting thermometers with colorful spheres which rise and fall to indicate temperature. decorative, functional thermometers are a great conversation piece perfect for the home or office sealed glass cylinder contains a clear liquid and several glass spheres of varying densities tag on the lowest sphere in the top group indicates the current temperature