Storm Cloud: A Weather Predicting Instrument (Weather Predictor, Fun Cloud-Shaped Barometer)In the 1800s, during his voyage with Charles Darwin, Admiral Robert Fitzroy used and later popularized the storm glass, which promised to predict the weather. A beautiful twist on this classic device, the Storm Cloud is a fun way of seeing what the weather has in store. Filled with a special liquid that responds to changes in the atmosphere, the crystals within the cloud shaped glass indicate whether it'll be fair, cloudy, rainy, windy, or stormy.