Fitzroy Storm Barometer

Predict a thunderstorm before everyone else. The Fitzroys Storm Glass is an ancient weather forecasting device consisting of a hand-blown glass tube filled with a liquid that undergoes interesting and unusual crystal growth in response to changing weather conditions. Famed meteorologist Admiral Fitzroy used a storm glass in 1750 as captain of the HMS Beagle on a historic voyage with Charles Darwin. This attractive 28cm storm glass makes a stylish room ornament, and interesting conversation piece.

Age: 12+ (this is not a toy it is made from glass)

What you get

Fitzroys Storm Glass (28cm) in an attractive box

How does it work?

A storm glass works on the principle that temperature and pressure affect solubility, sometimes resulting in clear liquid; other times causing precipitants to form. The liquid within the glass is a mixture of several chemicals including, distilled water, ethanol, potassium nitrate, ammonium chloride, and camphor. The exact method by which the storm glass works is not fully understood. Explanations include changes in barometric pressure, changes in temperature, and the effects of electricity across the glass. Nevertheless, the crystals in a storm glass are constantly evolving, and they are said to indicate the following weather conditions:

Clear Liquid = Fair Weather

Murky Liquid = Rainy Weather

Crystals at the top = Thunderstorms

Large Flaky Crystals = Cloudy skies, snow in winter

Thread of Crystals = Windy weather

Teach

• Properties of liquids and precipitates
• Crystal formation
• Weather forecasting
• Barometers
• History of weather forecasting and seafaring