Antique barometers

The barometer is an instrument for measuring atmospheric pressure.  The first barometer was invented in the mid-17th C but it did not become a household item before the early 19th C. Although early barometers existed also in water and gaz it is the mercury barometer  that is the most common.  The antique barometer to be hung on the wall is usually in a richly decorated mahogany or rosewood case which contains both a barometer and a thermometer.  The ship barometer is usually in a round case in brass.