Forget boring digital thermometers and outdated mercury ones when you can have something much cooler and safer. This Galileo Thermometer contains 10 weighted balls. The temperature can be read by observing which bauble is floating in the middle of the column.The 17-inch Galileo Thermometer employs the principles of buoyancy and density. The body of the thermometer is filled with paraffin oil and air, allowing the paraffin to expand and contract as needed. This isolates it for air pressure which can affect the density of liquids. As the temperature of the paraffin falls, it becomes denser, and the colored baubles inside will rise.
Package contains (1) Heebie Jeebies Galileo's Thermometer 17" - Ages 8+. Contains 10 balls. Accurate for a temperature range between 16 degrees Celsius and 40 degrees Celsius (60 degrees Fahrenheit and 104 degrees Fahrenheit).