The H.M.S. Beagle Stormglass is the infamous gadget used by Admiral FitzRoy, captain of the H.M.S. Beagle during the time that he along with his lieutenant, Charles Darwin voyaged to the Galapagos Islands in 1831. No one knows exactly how the contraption works but the stormglass can predict the weather. There several documents noting the accuracy of the stormglass. Inside the stormglass is a mixture of distilled water, potassium nitrate, ammonium chloride, alcohol, and camphor. If the stormglass is cloudy, it will rain, if crystals are seen it will be foggy or humid, if the glass is cloudy with tiny stars, thunderstorms are for sure.

To buy your own stormglass, click this link.