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linseed oil

(Encyclopedia)linseed oil, amber-colored, fatty oil extracted from the cotyledons and inner coats of the linseed. The raw oil extracted from the seeds by hydraulic pressure is pale in color and practically without ...

safety valve

(Encyclopedia)safety valve, device attached to a boiler or other vessel for automatically relieving the pressure of steam before it becomes great enough to cause bursting. The common spring-loaded type is held clos...

gas laws

(Encyclopedia)gas laws, physical laws describing the behavior of a gas under various conditions of pressure, volume, and temperature. Experimental results indicate that all real gases behave in approximately the sa...

Lebedev, Pyotr Nikolaevich

(Encyclopedia)Lebedev, Pyotr Nikolaevich pyôˈtə nyĭkəlīˈəvĭch lāˈbyədyəf [key], 1866–1912, Russian physicist. The most noted Russian physicist of his time, he studied at Strasbourg and Berlin and was...

artesian well

(Encyclopedia)artesian well, deep drilled well through which water is forced upward under pressure. The water in an artesian well flows from an aquifer, which is a layer of very porous rock or sediment, usually san...

cyclone

(Encyclopedia)cyclone, atmospheric pressure distribution in which there is a low central pressure relative to the surrounding pressure. The resulting pressure gradient, combined with the Coriolis effect, causes air...

Hales, Stephen

(Encyclopedia)Hales, Stephen, 1677–1761, English physiologist and clergyman. From 1709 he was perpetual curate of Teddington. His experimental studies in animal and plant physiology contributed greatly to the pro...

temperature inversion

(Encyclopedia)temperature inversion, condition in which the temperature of the atmosphere increases with altitude in contrast to the normal decrease with altitude. When temperature inversion occurs, cold air underl...

trade winds

(Encyclopedia)trade winds, movement of air toward the equator, from the NE in the Northern Hemisphere and from the SE in the Southern Hemisphere. The trade winds originate on the equatorial sides of the horse latit...

hydraulics

(Encyclopedia)hydraulics, branch of engineering concerned mainly with moving liquids. The term is applied commonly to the study of the mechanical properties of water, other liquids, and even gases when the effects ...