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safety lamp

(Encyclopedia)safety lamp, oil lamp designed for safe use in mines and other places where flammable gases such as firedamp (see damp) may be present. Its invention (c.1816) is usually attributed to Sir Humphry Davy...

picric acid

(Encyclopedia)picric acid trīˌnīˌtrōfēˈnōl [key], C6H2(NO2)3OH, a toxic yellow crystalline solid that melts at 122℃ and is soluble in most organic solvents. Picric acid is a derivative of phenol. It react...

porcelain

(Encyclopedia)porcelain [Ital. porcellana], white, hard, permanent, nonporous pottery having translucence which is resonant when struck. Porcelain was first made by the Chinese to withstand the great heat generated...

denaturation

(Encyclopedia)denaturation, term used to describe the loss of native, higher-order structure of protein molecules in solution. Most globular proteins exhibit complicated three-dimensional folding described as secon...

chiropractic

(Encyclopedia)chiropractic kīrəprăkˈtĭk [key] [Gr.,=doing by hand], medical practice based on the theory that all disease results from a disruption of the functions of the nerves. The principal source of inter...

hydrazine

(Encyclopedia)hydrazine hīˈdrəzēnˌ [key], chemical compound, formula NH2NH2, m.p. 1.4℃, b.p. 113.5℃, specific gravity 1.011 at 15℃. It is very soluble in water and soluble in alcohol. At ordinary tempera...

Higginson, Thomas Wentworth

(Encyclopedia)Higginson, Thomas Wentworth, 1823–1911, American author, b. Cambridge, Mass. A Unitarian minister, he was a leader in the abolitionist movement and was a member of a group that backed John Brown's a...

Kipling, Rudyard

(Encyclopedia)Kipling, Rudyard, 1865–1936, English author, b. Bombay (now Mumbai), India. Educated in England, Kipling returned to India in 1882 and worked as an editor on a Lahore paper. His early poems were col...

xerography

(Encyclopedia)xerography zərŏgˈrəfēˌ [key], also called electrophotography, method of dry photocopying in which the image is transferred by using the attractive forces of electric charges. A beam of light, us...

tar and pitch

(Encyclopedia)tar and pitch, viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. The heating or partial burning of w...