Ambient Weather WS-YG634 Antique Storm Glass Barometer with Cherry Wood Frame This traditional weather station is both a work of art and an instrument at home in any fine study, library, office or upscale restaurant; The rich, wood framed classic weather station measures barometric pressure (liquid) The concept that "decreasing atmospheric pressure predicts stormy weather" was postulated by Lucien Vidie and it's the basis for a weather prediction device called a storm glass or liquid barometer It consists of a glass sealed body, half filled with water; A narrow spout connects to the body below the water level and rises above the water level, where it is open to the atmosphere When the air pressure is lower than the sealed pressure, the water level in the spout will rise above the water level in the body and when the air pressure is higher, the water level in the spout will drop below the water level in the body All Ambient Weather Stations are covered by a 1-year warranty against manufacturing defects This traditional weather station is both a work of art and an instrument at home in any fine study, library, office or upscale restaurant. The rich, wood framed classic weather station measures barometric pressure (liquid). The concept that 'decreasing atmospheric pressure predicts stormy weather' was postulated by Lucien Vidie -- and it's the basis for a weather prediction device called a storm glass or liquid barometer. It consists of a glass container with a sealed body. A narrow spout connects to the body below the water level and rises above the water level, where it is open to the atmosphere. Includes 2 year limited Ambient Weather warranty All Ambient Weather Stations are covered by a 1-year warranty against manufacturing defects.