Goethe barometer / Donderglas - Barometer - Glass - Wood

Goethe barometer from the seventies.

Thunder glass
Dutchman Cornelis Drebbel invented the oldest known barometer, the motus perpetuus, forerunner of the thunder glass, around 1610, although the invention is credited in 1619 in a document to a certain Gijsbrecht de Donckere. In the second quarter of the 17th century, Drebbel’s principle was simplified and the thunder glass appeared on the scene. The reservoir contains a closed amount of air. When the external air pressure rises, it pushes the water down the spout. The air in the reservoir is then slightly compressed until the pressure in the reservoir equals that of the outside air. If the external air pressure falls, the force on the water column also decreases and the air in the reservoir pushes the water up the spout.
Thunder glasses were used both on ships and on land. The expression “gedonder in the glazen” comes from this thunder glass. Johann Wolfgang von Goethe studied the thunder glass around 1792–93 and popularized it in Germany, where it is called a Goethe glass, which should be regarded as apocryphal. Another questionable name is water barometer.
Thunder glasses are not precise measuring instruments; they respond not only to air pressure but also to temperature. When hung in a space where the temperature remains reasonably constant, however, the thunder glass forms a quickly reacting indicator of atmospheric pressure differences. Thunder glasses were manufactured as a beloved “water barometer” well into the 20th century.
Tip: you can also put colored water in it; that is decorative.

This lot has been carefully cleaned and will be carefully packed, sent by registered mail and insured (with Track & Trace so you can follow the shipment). Pickup in (Ridderkerk, South Holland) is also possible. I have tasty freshly ground coffee.
and coffee.