Ditch the mercury and go old school when it comes to a thermometer for your garden or porch! Galileo thermometers work using the principle of relative density and they’re also a very cool ornament for outside!
These thermometers consist of a simple glass tube filled with fluid. Inside the tube you’ll see colourful hand blown glass balls, each with a different density relative to the fluid in the tube. When the temperature rises or falls, the density of the liquid in the tube changes along with it which causes the density of the coloured balls relative to that liquid to also change. If the density of the ball is now less than that of the surrounding liquid, that ball will rise in the tube. On the other hand, if the density of the ball is increased in relation to the fluid in the tube, that coloured ball will sink in the tube.
Each of the coloured glass balls has a little tag on the bottom with a number corresponding to a temperature. To read a Galileo thermometer simply look at which ball is in the middle of the tube and read the label! The Galilio thermometer is easy to use and looks great too!
These outdoor Galileo thermometers come with a sturdy black metal frame and hook so you can hang it from a plant hook or on a fence. These glass thermometers are great gifts for gardeners and people who like to spend time in the yard!