Columbia Encyclopedia

Search results

441 results found

Ruskin, John

(Encyclopedia)Ruskin, John, 1819–1900, English critic and social theorist. During the mid-19th cent. Ruskin was the virtual dictator of artistic opinion in England, but Ruskin's reputation declined after his deat...

sea turtle

(Encyclopedia)sea turtle, name for several species of large marine turtles found in tropical and subtropical oceans. These turtles are modified for life in the ocean by having flipperlike forelimbs without toes and...

semiconductor

(Encyclopedia)CE5 N-type and P-type crystals: In a pure silicon crystal each silicon atom (Si) is surrounded by four valence electrons. In the N-doped semiconductor, illustrated in the left-hand figure, some sil...

manganese

(Encyclopedia)manganese măngˈgənēs, mănˈ– [key] [Lat.,=magnet], metallic chemical element; symbol Mn; at. no. 25; at. wt. 54.93805; m.p. about 1,244℃; b.p. about 1,962℃; sp. gr. 7.2 to 7.45, depending o...

marsupial

(Encyclopedia)marsupial märso͞oˈpēəl [key], member of the order Marsupialia, or pouched mammals. With the exception of the New World opossums and an obscure S American family (Caenolestidae), marsupials are no...

Wilde, Oscar

(Encyclopedia)Wilde, Oscar (Oscar Fingal O'Flahertie Wills Wilde), 1854–1900, Irish author and wit, b. Dublin. He is most famous for his sophisticated, brilliantly witty plays, which were the first since the come...

walnut

(Encyclopedia)CE5 Black walnut, Juglans nigra walnut, common name for some members of the Juglandaceae, a family of chiefly deciduous, resinous trees characterized by large and aromatic compound leaves. Species...

beryllium

(Encyclopedia)beryllium bərĭlˈēəm [key] [from beryl ], metallic chemical element; symbol Be; at. no. 4; at. wt. 9.01218; m.p. about 1,278℃; b.p. 2,970℃ (estimated); sp. gr. 1.85 at 20℃; valence +2. Ber...

zirconium

(Encyclopedia)zirconium zərkōˈnēəm [key], metallic chemical element; symbol Zr; at. no. 40; at. wt. 91.224; m.p. about 1,852℃; b.p. 4,377℃; sp. gr. 6.5 at 20℃; valence +2, +3, or +4. Zirconium is a very ...

rat

(Encyclopedia)rat, name applied to various stout-bodied rodents, usually having a pointed muzzle, long slender tail, and dexterous forepaws. It refers particularly to the two species of house rat, Rattus norvegicus...