Galileo Galilei was an Italian physicist, mathematician, astronomer and philosopher who had a major role in the scientific revolution of the sixteenth century. He was the first to discover that the density of liquid changes as a result of increasing or decreasing temperatures.
However, Galileo didn’t invent the Galileo Thermometer. Instead, it was named in his honor since without his discoveries, it wouldn’t have been possible to invent. The thermometer is made up of a sealed glass cylinder.
Inside there is a clear liquid and a series of bulbs. Each bulb has a weight attached to it. As the temperature changes, they rise and fall depending of a number of mathematical principles. And the Galileo Thermometers are not only functional; they are also very beautiful.
On each of the bulbs the weight is also tagged. A number and a degree symbol are engraved on each one. The weights are finely regulated counterweights. Each of the weights is a little different from the others. The colored water in the bubbles is added so that each one will have the same density – but it certainly adds to the overall attraction of this special thermometer.
The mathematical principles applied to the Galileo thermometer are straightforward. Each bulb in the thermometer has the same volume and therefore exactly the same density. This means that each bulb has the same magnitude of both gravitational and buoyant forces. Gravity pushes down, buoyancy upwards.
Each bulb is defined by the mass that is suspended from its base. This mass increases the relative weight of the bulb as well as the effect of gravity on it. The weight means that each of the bulbs has a slightly different density to the others.