River City 910-100 Sun and North Wind Weatherball quickly indicates any changes in atmospheric pressure.
Renaissance scientist Evangelista Torricelli (1608-1647) discovered the first barometer, proving that air pressure was subject to change. It is believed that Goethe, the famous German playwright, developed this simple but effective barometer using the principles established by Torricelli.
The air trapped by the liquid maintains a stead pressure. When high pressure and good weather are approaching, the liquid is pushed down the spout. When low pressure and bad weather invade your region greater pressure trapped inside the Weatherball causes the liquid in the spout to rise. If liquid spills out of the top you should take shelter!
