RADCLIFFE COLLEGE 409 RADICAL the Forest"; but that which made her reputation was the "Mysteries of Udol- pho." She died in London, Feb. 7, 1823. RADCLIFFE COLLEGE, an educa- tional non-sectarian institution in Cam- bridge, Mass., for women; founded in 1879; reported at the close of 1919: Professors and instructors, 128; stu- dents, 561; president, L. R. Briggs, LL. D. RADETZKY, JOSEPH WENZEL, COUNT, an Austrian general; born in the castle of Trebnitz, in Bohemia, Nov. 2, 1766. Called to participate in the long struggle against Napoleon, and hav- ing won his way to the rank of Major- General, he fought at Agram and Erlin- gen; distinguished himself in the battles of 1813, 1814, and 1815; and at Kulm, Leipsic, and Brienne. Having been suc- cessively governor of Ofen in Hungary, and Lemberg in Poland, he was, in 1822, appointed commander-general of the Lombardo-Venetian kingdom. In 1848 the people of Milan rose against their Austrian oppressors, and after a gallant struggle drove them out of the city. Radetzky retreated upon Verona, to await the arrival of re-enforcements. Shortly afterward, Charles Albert, King of Sardinia, joined the popular cause, but was defeated at Novara. This bat- tle decided the fate of the Italian cause, and Austrian tyranny was again trium- phant in Lombardo-Venetia. After ^ 73 years of service in the Austrian armies, Radetzky resigned in the year 1857. He died in Milan, Italy, Jan. 5, 1858. RADHANPUR, chief town of a pro- tected state in Bombay presidency, In- dia, 150 miles N. W. of Baroda. It is surrounded with walls and incloses a fortified castle, the residence of the na- tive prince. The state of Radhanpur has an area of 1,150 square miles. Pop. about 100,000. RADIANT, in botany, diverging from a common center, like rays. In heraldry an epithet applied to an ordinary or charge, when it is presented edged with rays or beams; rayonnant; reyonnee. In astronomy, the point in the heavens from which a star shower seems to pro- ceed. In geometry, a straight line pro- ceeding from a given point or fixed pole, about which it is conceived to revolve. In optics, the luminous body or point from which rays of light falling on a lens or mirror diverge. RADIATA, in zoology, a term intro- duced by Cuvier, in 1812, for the lowest of his great groups or embranchments. He described them as having radial in- stead of bilateral symmetry, apparently destitute of nervous system and sense organs, having the circulatory system rudimentary or absent, and respiratory organs on or coextensive with the sur- face of the body; and included the Echi- nodermata, Acalepha, Entozoa, Polypi, and Infusoria. Wider knowledge led to the narrowing of the limits of this group, and through Agassiz pleaded for its retention (with the three classes of Polypi, Acalephse, and the Echinoderms) . Huxley's "Lectures on Comparative Anatomy" finally broke up what is called the "radiate mob" and distributed its constituents among the Echinodermata, Polyzoa, Vermes, Ccelenterata, and Pro- tozoa. RADIATION, in physics, the trans- mission of heat, light, or actinic power (hence known as forms of "radiant en- ergy") from one body to another without raising the temperature of the interven- ing medium. It takes place in all direc- tions around a body. In a homogeneous medium it takes place in straight lines. Radiation proceeds in vacuo as well as through air. Its intensity is propor- tioned to the temperature of the source, and it diminishes according to the obliq- uity of the rays with respect to the radiant surface, and the radiating or emissive power of a body, or its capa- bility of emitting at the same tempera- ture, and with the same extent of sur- face, greater or less quantities of heat. The energy received from a radiating body is inversely proportional to the square of the distance, and the radiation of a body is exactly proportional to its absorbing power. If the radiating power of lampblack be reckoned at 100, that of platinum foil is 10.80; copper foil, 4.90; gold leaf, 4.28, and pure lam- inated silver 3.80. Solar radiation is the radiation from the sun; terrestrial radi- ation that from the earth into space. RADICAL, in chemistry, a group of elements common to a more or less nu- merous series of allied compounds, and unaffected by the processes whereby these compounds are transformed one into an- other, e. g.j Ethyl (C=H.), the radical of common alcohol (C:HoHO). In mathe- matics, an indicated root of an imperfect power of the degree indicated. In phi- lology, (1) A radix, root, or simple un- derived, uncompounded word. (2) A letter which belongs to the root; a primi- tive letter. In English and American politics, an ultra-liberal, verging on Socialism; one of that party in the state which desires to carry out a radical re- form of the constitution, and to give greater power to the democracy. The term was first used in England and ap- plied as a party name in 1818 to Henry Hunt, Major Cartwright, and others of
