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psychrometer

(Encyclopedia)psychrometer sīkrŏmˈĭtər [key], one of many instruments used for measuring the water vapor content or relative humidity of the atmosphere. It consists of two identical thermometers—the wet-bulb...

humidity

(Encyclopedia)humidity, moisture content of the atmosphere, a primary element of climate. Humidity measurements include absolute humidity, the mass of water vapor per unit volume of natural air; relative humidity (...

vaporization

(Encyclopedia)vaporization, change of a liquid or solid substance to a gas or vapor. There is fundamentally no difference between the terms gas and vapor, but gas is used commonly to describe a substance that appea...

thermoelectricity

(Encyclopedia)thermoelectricity, direct conversion of heat into electric energy, or vice versa. The term is generally restricted to the irreversible conversion of electricity into heat described by the English phys...

Gunter, Edmund

(Encyclopedia)Gunter, Edmund, 1581–1626, English mathematician and astronomer, educated at Westminster School, London, and Christ Church, Oxford. He invented (1618) a small portable quadrant and discovered (1622)...

land art

(Encyclopedia)land art or earthworks, art form developed in the late 1960s and early 70s by Robert Smithson, Robert Morris, Michael Heizer, and others, in which the artist employs the elements of nature in situ or ...

Le Châtelier's principle

(Encyclopedia)Le Châtelier's principle, chemical principle that states that if a system in equilibrium is disturbed by changes in determining factors, such as temperature, pressure, and concentration of components...

slide rule

(Encyclopedia)slide rule, instrument for making numerical computations and readings, the results of which may be read easily and quickly after performing simple mechanical manipulations. Multiplication and division...

weighing machine

(Encyclopedia)weighing machine: see balance; scale. ...

vernier

(Encyclopedia)vernier vûrˈnēr [key], auxiliary scale, either straight or an arc of a circle, designed to slide along a fixed scale. Its unit divisions, usually smaller than those on the fixed scale, permit a far...