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airship

(Encyclopedia)airship, an aircraft that consists of a cigar-shaped gas bag, or envelope, filled with a lighter-than-air gas to provide lift, a propulsion system, a steering mechanism, and a gondola accommodating pa...

hydrogen sulfide

(Encyclopedia)hydrogen sulfide, chemical compound, H2S, a colorless, extremely poisonous gas that has a very disagreeable odor, much like that of rotten eggs. It is slightly soluble in water and is soluble in carbo...

pumice

(Encyclopedia)pumice pŭmˈĭs [key], volcanic glass formed by the solidification of lava that is permeated with gas bubbles. Usually found at the surface of a lava flow, it is colorless or light gray and has the g...

states of matter

(Encyclopedia)states of matter, forms of matter differing in several properties because of differences in the motions and forces of the molecules (or atoms, ions, or elementary particles) of which they are composed...

deafness

(Encyclopedia)deafness, partial or total lack of hearing. It may be present at birth (congenital) or may be acquired at any age thereafter. A person who cannot detect sound at an amplitude of 20 decibels in a frequ...

electron tube

(Encyclopedia)CE5 Triode electron tube electron tube, device consisting of a sealed enclosure in which electrons flow between electrodes separated either by a vacuum (in a vacuum tube) or by an ionized gas at l...

carbon monoxide

(Encyclopedia)carbon monoxide, chemical compound, CO, a colorless, odorless, tasteless, extremely poisonous gas that is less dense than air under ordinary conditions. It is very slightly soluble in water and burns ...

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...

spastic paralysis

(Encyclopedia)spastic paralysis, form of paralysis in which the part of the nervous system that controls coordinated movement of the voluntary muscles is disabled. In spastic paralysis the nerves controlling muscle...

touch

(Encyclopedia)touch, tactile sensation received by the skin, enabling the organism to detect objects or substances in contact with the body. End organs (nerve endings) in the skin convey the impression to the brain...