This sweet storm cloud is used to predict the weather , helpful to know if you need a brolly or not! Use the storm cloud to predict the weather, as Admiral Fitzroy did on his classic voyage with Charles Darwin, aboard the HMS Beagle. The crystals inside react to different weather conditions Whether on the high seas, or the captain's table, the liquid inside the storm cloud will indicate what the weather has in store. This reworking of a classic device will add some atmosphere to your day. Beechwood + Glass [Materials] Glass, wood; Main ingredients: ammonium chloride, potassium nitrate, camphor, distilled water, ethanol 12,8 x 3.4 x 10.7