A storm glass is a novelty that was once believed capable of forecasting bad weather, but we now know its simply a mesmerizing thermal reaction, similar to a lava lamp. Inside the hermetically sealed glass is a supersaturated solution of camphor, ethanol, ammonium chloride, potassium nitrate, and distilled water. This solution can form crystals of various patterns and quantities.
The premise of the storm glass is that changing weather affects the solubility of the mixture which, it was believed, produces crystals in strange shapes, or causes existing crystals to melt back into solution. In fact, Admiral and pioneering meteorologist Robert FitzRoy used the storm glass as commander of the HMS Beagle on Charles Darwin’s scientific voyage and wrote about its storm-predicting ability.
