A stormglass is a weather prediction device. Technically, it is a type of barometer -a device that responds to atmospheric pressure. Its main component is a sealed glass capsule that contains a specific chemical mixture: 2.5 g. of potassium nitrate; 2.5 g. of ammonium chloride; 33 mL. of distilled water; 40 mL. of ethanol and 10 g. of camphor. This solution changes its appearance depending on the weather to be: transparent if the weather will be bright and clear; if the weather will be cloudy or rainy, the liquid will also cloud by forming a series of crystals at the bottom of the capsule; humid or foggy weather will cause the formation of small dots in the liquid, etc. I am unaware of the scientific principle behind this highly visual weather forecasting object, although some attribute the changes in the appearance of the liquid to electromagnetic changes caused by weather and sun storms. First used by an admiral Fitzroy aboard the HMS Beagle during Darwin's five year historic voyage around the world in the early 19th century, the present of this archaic analog device is bright: it is still commercialized worldwide by a number of companies that sell nautical objects. Despite its glorious origins and shiny appearance, as an object, the stormglass is small -–about 14.5 cm (5.75 in.) high and 4.2 cm (1.65 in.) in diameter-– and devoid of any remarkable formal features. Anonymity may very well be what good measuring devices should aspire to.
