Four hundred years ago Galileo discovered that liquids change in density as temperature changes. This revelation lead Galileo to develop a rudimentary thermometer, which was perfected by his protégés Torricelli and Viviani.

The Galileo thermometer is comprised of a glass cylinder which contains glass spheres of different and specific weights, suspended in liquid. Each glass sphere is coloured and labelled with its temperature. Each glass sphere’ specific weight corresponds with a temperature and one can read the current temperature by looking at the glass sphere that is the lowest hanging sphere within the top floating group. The theory behind the thermometer is that when temperature rises, the liquid in the glass cylinder becomes less dense and spheres slowly sink. On the other hand when the temperature decreases the spheres will rise. This thermometer is as useful as it is striking and the perfect gift for those looking for something quirky and scientific.