Due to the holidays, we will be closed from 3.00 pm on Friday 24 July until Tuesday 11 August inclusive. No orders will be dispatched during this period. You are, of course, still welcome to place an order. From Wednesday 12 August, we will be back to serve you as usual. We will then process orders in the order in which they are received and dispatch them as soon as possible.
How does it work?
Discover the fascinating science behind the Galileo thermometer! On this page, we explain how this ingenious thermometer works, based on the principles of Galileo Galilei. Learn how the glass spheres, filled with coloured liquids, react to changes in temperature and how this beautiful instrument takes accurate measurements. Whether you’re a science enthusiast or simply curious about how things work, you’ll be amazed by the simplicity and beauty of this design.
A Galileo thermometer is a thermometer in the form of a sealed glass cylinder containing a transparent hydrocarbon liquid and various (often coloured) glass beads. It is named after Galileo Galilei. When the temperature changes, the beads rise or fall. Each bead has its own characteristic temperature at which it begins to float in the liquid.As the temperature changes, so does the density of the liquid, causing the glass beads, with their own characteristic densities, to be pushed up or down. This is in accordance with Archimedes’ principle, as objects with a lower mass density float and those with a higher density sink. A glass bead remains suspended at the point where the density of the surrounding liquid is equal to that of the glass bead.When making this thermometer, the glass beads with the highest density are placed at the bottom, so that as the temperature changes, one glass bead at a time can make the journey from the bottom to the surface (or vice versa).