With this magical storm glass, you will be better informed than the weather god himself. The white crystals predict the weather. The modern globe is filled with a camphor salt solution. The salt crystals inside react to electromagnetic waves as well as changes in air pressure and temperature. Weather forecasts of up to 12 hours are possible, depending on the placement. If the crystals are visible, humid and foggy weather is expected, while a cloudy glass indicates a storm is on the way. Conversely, if the glass is clear, you can look forward to fair weather conditions. Even Charles Darwin relied on such a storm glass during his travels.