A runny nose. Constant clear and watery nasal discharge from the nose is usually the first complaint. If allergies are the cause of the runny nose then itchiness of the nose and eyes will also be present. A runny nose also commonly results in a stuffy congested feeling in the nose.
by Guest Writer Jenni Worboys. A barometer is a widely used weather instrument that measures atmospheric pressure (also known as air pressure or barometric pressure) - the weight of the air in the atmosphere.
In a sealed-tube manometer, the pressure reference is a vacuum, or zero absolute pressure. The most common form of a sealed-tube manometer is the conventional mercury barometer used to measure atmospheric pressure. A manometer can be designed to directly measure absolute pressure. The manometer in Figure 5 measures the pressure compared to zero absolute pressure in a sealed leg above a mercury column. The most common form of this manometer is the conventional mercury barometer used to measure atmospheric pressure.