Columbia Encyclopedia

(Encyclopedia) mutation, in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any change in the delica...

(Encyclopedia) magic, in religion and superstition, the practice of manipulating and controlling the course of nature by preternatural means. Magic is based upon the belief that the universe is populated by unseen f...

(Encyclopedia) induction, in electricity and magnetism, common name for three distinct phenomena. Electromagnetic induction is the production of an electromotive force (emf) in a conductor as a result of a changing ...

(Encyclopedia) James, William, 1842–1910, American philosopher, b. New York City, M.D. Harvard, 1869; son of the Swedenborgian theologian Henry James and brother of the novelist Henry James. In 1872 he joined the ...

(Encyclopedia) ultraviolet radiation, invisible electromagnetic radiation between visible violet light and X rays; it ranges in wavelength from about 400 to 4 nanometers and in frequency from about 1015 to 1017 hert...

(Encyclopedia) narodniki närôdˈnĭkē [key], Russian populists, adherents of an agrarian socialist movement active from the 1860s to the end of the 19th cent. Influenced by the writings of Aleksandr Herzen, the n...

(Encyclopedia) Nashe or Nash, Thomas both: năsh [key], 1567–1601, English satirist. Very little is known of his life. Although his first publications appeared in 1589, it was not until Pierce Penniless His Suppli...

(Encyclopedia) Laurens, Henry lôrˈənz, lärˈ– [key], 1724–92, political leader in the American Revolution, b. Charleston, S.C. A wealthy merchant and planter, he was, in the years preceding the Revolution, a...

(Encyclopedia) ohmmeter ōmˈmēˌtər [key], instrument used to measure the electrical resistance of a conductor. It is usually included in a single package with a voltmeter, and often an ammeter. In normal usage, ...

(Encyclopedia) monitor, any of various, mostly tropical lizards. A monitor lizard has a heavy body, long head and neck, long tail that comes to a whiplike end, and strong legs with sharp claws. Its slender, forked t...