Barometer
an instrument used for measuring the atmospheric pressure. BAROMETER, an instrument used for The most common form of barometer is what is called a cistern barometer. It The most common form of barometer is consists essentially of a straight glass tube about 33 inches long, filled with mercury, and dipping into a cistern of tube about 33 inches long, filled with the same metal. It is affixed to a stand, on the upper part of which is a graduated scale to mark the height in inches at which the mercury stands. When uated scale to mark the height in inches side with it to note the temperature at which the pressure of the atmosphere is form of a siphon. It has two scales with a common zero point, and graduated in contrary directions. As the one branch, a common zero point, and graduated in tern, and the other or longer one to the tube, the difference between the two levels is the true height of the mercury.
A barometer is popularly termed a weather glass. In order to adapt it for A barometer is popularly termed a the wheel barometer. It is a siphon barometer, having in its shorter leg a float, a string from which passes over a pulley, and is connected with a weight somewhat lighter than the float. To the pulley is affixed a needle, which moves round a circle graduated to represent the different variations in the weather. Speaking broadly, a barometer rises for good BARONET and falls for bad weather, but there are exceptions to this rule.
Middle Ages, the title baron, derived