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Earth Summit

(Encyclopedia)Earth Summit: see United Nations Conference on Environment and Development. ...

All Souls' Day

(Encyclopedia)All Souls' Day, Nov. 2 (exceptionally, Nov. 3), feast of the Roman Catholic Church on which the church on earth prays for the souls of the faithful departed still suffering in purgatory. The proper of...

earth, in geology and astronomy

(Encyclopedia)CE5 A. Cross section of the earth, showing its shells B. Detailed cross section of the crust and upper mantle: The lithosphere consists of the hard rock in the crust and upper mantle, lying above t...

Day, Benjamin

(Encyclopedia)Day, Benjamin, 1838–1916, American printer; son of Benjamin Henry Day. While working in New York City, Day invented a process, utilizing celluloid sheets, for shading plates in the color printing of...

day nursery

(Encyclopedia)day nursery, day-care center, or crèche krĕsh [key], institution for the care of the children of working parents. Originating in Europe in the late 18th and early 19th cent., day nurseries were est...

earth, in chemistry

(Encyclopedia)earth, in chemistry, metallic oxide not readily reducible by chemical means, e.g., alkaline earths, rare earths, and alumina. The name is also applied to certain absorbent clays, e.g., fuller's earth,...

Veterans' Day

(Encyclopedia)Veterans' Day, holiday formerly observed in the United States as Armistice Day in commemoration of the signing of the Armistice ending World War I. Nov. 11 officially became Veterans' Day on May 24, 1...

rare-earth metals

(Encyclopedia)rare-earth metals, in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, whi...

degree-day

(Encyclopedia)degree-day, a unit of measure used to estimate the fuel and power requirements in heating and cooling a building; it is equal to a difference of 1 degree between the outdoor daily average temperature ...

Memorial Day

(Encyclopedia)Memorial Day, holiday in the United States observed in late May. Previously designated Decoration Day, it was inaugurated in 1868 by Gen. John A. Logan for the purpose of decorating the graves of Civi...