An instrument for measuring heights by observation of barometric pressure; esp., one for determining heights by ascertaining the boiling point of water. It consists of a vessel for water, with a lamp for heating it, and an inclosed thermometer for showing the temperature of ebullition.

An instrument used to determine atmospheric pressure or elevation by observing the boiling point of water or other liquids. The sensitivity of the hypsometer increases with decreasing pressure, making it more useful for high altitude work.

any of several tools or instruments designed to measure the height of trees. The clinometer is such a tool.