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Common Weights and Measures (table)

(Encyclopedia)Common Weights and Measures Length Area Volume and Capacity (Liquid and Dry) Weight (Mass) ...

atomic clock

(Encyclopedia)atomic clock, electric or electronic timekeeping device that is controlled by atomic or molecular oscillations. A timekeeping device must contain or be connected to some apparatus that oscillates at a...

carbon

(Encyclopedia)CE5 The three solid forms of pure carbon: In the diamond crystal each carbon atom is surrounded symmetrically by four other carbons (at each of the four corners of a tetrahedron). In the graphite c...

hygrometer

(Encyclopedia)hygrometer hīgrŏmˈətər [key], instrument used to measure the moisture content of a gas, as in determining the relative humidity of air. The temperature at which dew or frost forms is a measure of...

folk medicine

(Encyclopedia)folk medicine, methods of curing by means of healing objects, herbs, or animal parts; ceremony; conjuring, magic, or witchcraft; and other means apart from the formalized practice of medical science. ...

perfume

(Encyclopedia)perfume, aroma produced by the essential oils of plants and by synthetic aromatics. The burning of incense that accompanied the religious rites of ancient China, Palestine, and Egypt led gradually to ...

von Braun, Wernher

(Encyclopedia)von Braun, Wernher vôn broun [key], 1912–77, German-American rocket scientist and astronautics engineer, b. Germany, grad. Berlin Technological Institute (B.S., 1932), Univ. of Berlin (Ph.D., 1934)...

sponge

(Encyclopedia)sponge, common name for members of the aquatic animal phylum Porifera, and for the dried, processed skeletons of certain species used to hold water. Over 4,500 living species are known; they are found...

vasectomy

(Encyclopedia)vasectomy, male sterilization by surgical excision of the vas deferens, the thin duct that carries sperm cells from the testicles to the prostate and the penis. Vasectomy is a popular method of birth ...

calorimetry

(Encyclopedia)calorimetry kălˌərĭmˈətrē [key], measurement of heat and the determination of heat capacity. Heat is evolved in exothermic processes and absorbed in endothermic processes; such processes includ...