The Fitzroy Storm Glass is a sealed glass column containing a chemical compound that reacts to atmospheric conditions. According to the findings of Vice-Admiral Fitzroy, this glass barometer forecasts the weather based on changes in the formation of crystals inside the column. If the liquid is clear, the weather will be bright and clear. If the liquid is cloudy, the weather will be cloudy as well, perhaps with precipitation. If there are small dots in the liquid, humid or foggy weather should be expected. A cloudy glass with small stars may indicate thunderstorms. If the liquid contains small stars on sunny winter days, expect snow. If there are large flakes throughout the liquid, it should be overcast in temperate seasons or snowy in the winter. Crystals at the bottom indicate frost. Threads near the top mean that it will be windy.
When you receive your storm glass, it will be in a state of disruption from the shipping process. It is very important that you “reset” your storm glass after you receive it. To ‘reset” your storm glass, carefully lay it on its side on a large towel. Use a blow dryer to gently warm the glass while rolling it back and forth on the towel. Move the blow dryer in a side-to-side pattern to avoid over heating. Continue warming up the glass until the crystals disappear and the column is almost completely clear. DO NOT heat the glass to the point where the liquid becomes HOT. After you have cleared the entire column, place the storm glass in a secure location where it will not be bumped or moved. Due to the sensitive nature of the crystals inside the Storm glass, you will want to avoid moving it unnecessarily. Repeat this resetting process at least 2 times a year or when you notice a lack of change within the glass.