DRAPER. 444 DRAPER. York Meteorolofjival Olis<'rvatory. The solfrc- (.ordiii;.' iTic'ti'oroluj.'ioal iiislruiiu'iits eiiiployed in tUat institution an- liaM'd cliiflly uiion his ilo- sigiis. Among his literary eontrilnitions to sei- enee may be menlioneil tlie well-known treatise on the Cause of I'litiiniuuiu, whieli has also been translated and rejirinted abroad. DRAPER, Hk.nky (1837-S2). An Ameriean scientist, the son of John William Draper. He was born in Prinee Kdward County, Va.; studied in Xew York from ISo'l to 1S.'>4_, and began the practice of medicine in 18J8. He was then pro- lessor of physiology in New York I'niversily from 18iiO to IStiti, jjrofpssor in the medical school from ISOli to 1873, and afterwards pro- fessor of chemistry, lie constructed large tde- 6co|)es and devoted himself to celestial photog- raphy, rendering important service to astronomy and astroi)hysics. He published .1 Text-book on i'licniistri/ (18C6), and uian,v vaUiaMe papers. DRAPER, .Toiix CiiRLSTOPiiER (1S35-8o). An Anu'rican ])hysician, born in Virginia. He was a son of John William Drajjcr. He entered the academic department of Xew York University in 1852, but subsequently abandoned the study of the classics, attended the course in medicine, and graduated in 185". He was professor of analyt- ical chemistry. New York University. IS.'SSlil; of chemistry at Cooper Union, New York City, 18(iO-(i3: of natural science at the College of the City of New York. 18fi3-S5; and of chemistry in the medical department of New York Uni- versity, 1800-85. He contributed inimerous ar- ticles to medical rnd scientific journals, was editor, in 1872-73, of the Year-Book of Yu/iire and SvUiH-c, and for throe years had charge of the department of natural science in Kcrihiier's Moiitlih/. His important works include: The Production of Urea (1850); Experiments on ]{isiiirtititin (1850): TcxtUool; on Anatomy, Physioloyy, and Hygiene (1866): .1 Practical Lahoratoni Course in Medical Chemistry (1882); :ind a Text-Book of Medical Physics (1885). DRAPER, John- Willi.m (1811-82). An Anierlian clieniist, physiologist, and ])hilosophi- cal writer. He was born near 1-iverpool, Kng- land. and was educated at a Wesleyan school at Woodhouse Grove, and at London I'niversity. In 1831 he joined some of his relatives who had emigrated to America, and in 1830 took his degree of doctor of medicine in the Universit,v of Pennsylvania and was appointed professor of natural philosophy, chemistry, and ph.vsiologj' in llampden-Sidney "CuUege. N'irginia. In 1830 he removed to New York, where he was con- nected with the college department of the University of the City of New York; and in 1841 joined Drs. Mott, Patterson, and others in founding the medical school of New York Uni- versity, in which he was at first professor of chemistry, and after 1850 of physiology. He published a Treatise on the Forres irhieh Pro- duce Orrinnization in Plants (1844); Text-Book of Chemistry (1846); a Text-Book of Xaturnl Philosophy (1847): and Human Physiolotjii, f!tatical and Dynamical: or, the Conditions and Course of Life of Man. Dr. Draper's lasting contributions to physi- ology and to pure chemistry were few and rela- tively unimportant. On the other hand, his name is associated with a number of results of the greatest value in physical chemistry, es])ccially in |>hotocliemistry (q.v. ). The cliein- ical action of light early attracted his attention and for many years formed liis favorite subject of investigation. He succeeded in demonstrat- ing that ditl'erent colors of light have an iniequal inlluence on the decomposition of car- bonic acid by the green pigment of plants. The s|K'ctra of light emitted liy incandescent sub- stances engaged his attention as early as 1847, and his memoirs show that at that "early date he had already grasped the wonderful possibili- ties of spectrum analysis in botli chemistry and astroncjmy. He further succeeded in showing that all parts of the spectrum, the invisible as well as the visible ones, are capalde of chemical action. His improvements in the art of photog- raphy entitle him to an eminent ])lace among the great inventors of the nineteenth century. The l)rinciple of ])hotography was established by the Frenchman Daguerre: but Daguerre's |)roces3 was imperfect and practically incapable of use- ful application. It was Dmjier's imju-ovements that rendered it possible to apply i)iiotogra))hy to the rei)resentation of the human countenance, and the first photograph was taken by Draper in 1S30, in the old building of the New York University. A valualile collection of Drajier's i)ub- lications was puldished in 1878. under the title, Scientific }temoirs, Beiny Exi>rrimenlal Con- tributions to a Knon-ledye of Iladiant Kneryy. Though a life-long teacher of science and a prolific writer on scientific subjects, Dra])er will, perhaps, best be remembered as the author of tliree works which more properly belong to the domain of ])hilosophical history. The first of these and the most important is The History of the Intellectual lt< rrloinnent of Europe (2 vols., 1863), in which he attempts to apply the methods of science to hum:in history, and to prove in- ductively that '"social advancement is as com- pletely lUlder (he control of natural law as is lio<lily growth." Much of his data, both scientific and historical, has been superseded, and scmic of his conclusions are discredileil, Imt the work is characterized by consideralde erudition and .1 renu>rkal)le clearness of presentation, and is still much read. His History of the American Civil Mar (3 vols., 1807-70). thovigh it gives a graphic atid fairly accurate account of the military operations, is chiefly valuable for its claliorate analysis of the causes, inniiediate and remote, which made a war between the North and the South inevitable. The most popular of his works, however, is his History of the Conflict Betieeen lleliqion ami Science (New York. 1874), a candid, philosophical, and fairly comprehensive treatment of the subject. Consult Harker's ■■-Memoir," in volnn:e ii. of the Bioyraphical Memoirs of the yational Academy of Science. DRAPER, Lyji.vn Copeland (iS15-{)1). An American historian and educator. Ho was bom at Hamburg (now Kvans). Krie County, N. Y., and was educated at Cranville College (now Denison University). Ohio. In 1840 he conceived the idea of writinj; a history of the Tndi:in wars of the United States, and with this in view visited many pioneers, Indian chiefs, and others, who were in any way identified with the early Indian campaigns. He conlirnied these investi- gations for twenty-five years, traveling thou- sands of miles through every part of the United
