Historic devices still provide practical applications
For centuries, households have hung beautifully crafted devices to help the residents tell the weather. Two examples of these items are the weather glass barometers and Galileo thermometers. Today, you can own these beautiful reproduction instruments. Not only are they lovely accent and conversation pieces, but useful tools for understanding weather patterns.
A weather glass is a barometer. These barometers consist of hand blown glass orbs, often with a side spout. The containers usually have some kind of liquid, such as colored water. As the air pressure changes, the water rises or falls in the side spout, indicating a change in the barometric pressures. Sometimes these barometers are known as a water barometer, weather glasses or a storm glass.
Weather glasses have been used since the 16th Century. Some people attribute the invention of the weather glass to Dutch nobleman Gheijsbrecht de Donckere, while others believe the first inventor of the barometer was Italian mathematician, Evangelista Torricelli, in 1645.
Weather glasses have long held fascination for people, including German writer Johan Wolfgang Goethe, who was very interested in studying weather. Goethe had a weather glass (it hangs in the museum of his former home). Goethe was fascinated by the weather glass and introduced it throughout many countries in Europe. It was sometimes referred to as a Goethe barometer.
Many people believe that the pilgrims brought weather glasses with them on their voyage to the new world, where these barometers became known as Cape Cod weather glasses, or thunder bottles. They grew to be very popular with fishermen and farmers.
Galileo thermometers are another beautiful glass item, but the shape and function is very different from a barometer. You may have seen a Galileo thermometer and interpreted it as an art piece, without realizing the functionality behind it. Galileo thermometers are made of a clear glass cylinder containing clear liquid. Inside the liquid floats a series of glass spheres. These spheres rise or sink in relation to the temperature of the liquid. The warmer the temperature, the less dense the fluid, the more apt the spheres are to sink.
Each of the glass spheres are filled with a different colored liquid. Often these spheres or bulbs have weighted medallions that are counterweights to the fluid. As the temperature changes, the appropriate spheres either sink to the bottom, or rise to the top.
Both the Galileo thermometers and the weather glass are examples of beautiful craftsmanship and art, but both also offer a practical function in the home. They are wonderful examples of science in action, and beautifully designed to fit in a variety of decors.