Barometer :: Barometer (n.) An instrument for determining the weight or pressure of the atmosphere, and hence for judging of the probable changes of weather, or for ascertaining the height of any ascent..
Hydrobarometer :: Hydrobarometer (n.) An instrument for determining the depth of the sea water by its pressure.
Thermobarometer :: Thermobarometer (n.) An instrument for determining altitudes by the boiling point of water.
Water Barometer :: Water barometer () A barometer in which the changes of atmospheric pressure are indicated by the motion of a column of water instead of mercury. It requires a column of water about thirty-three feet in height.