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fuller's earth

(Encyclopedia)fuller's earth, mineral substance characterized by the property of absorbing basic colors and removing them from oils. It is composed mainly of alumina, silica, iron oxides, lime, magnesia, and water,...

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...

alkaline-earth metals

(Encyclopedia)alkaline-earth metals, metals constituting Group 2 of the periodic table. Generally, they are softer than most other metals, react readily with water (especially when heated), and are powerful reducin...

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,...

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...

Columbus Day

(Encyclopedia)Columbus Day, holiday commemorating Christopher Columbus's discovery of America. It has been traditionally celebrated on Oct. 12 throughout most of the United States, parts of Canada, and in several o...

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 ...

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...

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