INDEX 



Trichinosis, character of the disease 

 and its cause discovered, 363-365. 



Tuke, William, inaugurates reform in 

 treatment of the insane, 395. 



Tyndall, John, his advocacy of May- 

 er's doctrine of the conservation of 

 energy, 221, 223; and of Darwin's 

 theory of natural selection, 313; 

 his endorsement of the germ the- 

 ory, 320, 386. 



ULTRA-GASEOUS or fourth state of 

 matter, theory of, 247. 



Undulatory theory of light, establish- 

 ment of, 192-204. 



Uniformitarianism, Sir Charles Ly- 

 ell's advocacy of the doctrine of, 

 99-102, 127, 131. 



VACCINATION, its discovery as a means 

 of preventing small-pox, 42 ; its 

 application as a preventative of 

 other diseases by virus prepared in 

 the laboratory, 386-390. 



Valency, development of the law of, 

 269/275. 



Valentin, Gabriel Gustav, his study 

 of pancreas, 347. 



Van 't Hoof, Professor, his establish- 

 ment of stereo-chemistry, 448, 44S. 



Venetz, M., an early believer in and 

 advocate of the glacial theory, 134. 



Vertebrate paleontology, establish- 

 ment of, 91-97. 



Vinci, Leonardo da, his early recog- 

 nition of the true character of fos- 

 sils, 88. 



Virchow, Rudolf, his demonstration 

 of Schwann's cell theory, 344, 345 ; 

 his researches which lead to the 

 discovery of trichinosis, 363, 364. 



Volta, Count Alessandro, his inven- 

 tion of the voltaic pile, 27, 28. 



Vortex theory of atoms, the, experi- 

 ments to prove, 236-240 ; an un- 

 solved problem, 446, 447. 



Vulcan, a hypothetical planet located 

 by Leverrier, 49. 



WALLACE, ALFRED RUSSELL, his re- 

 markable conception of the theory 

 of natural selection contemporane- 

 ously with Darwin, 307-310. 



Waller, Professor, his discovery of 

 " trophic centres," 427. 



Warren, John C., mounted, described, 

 and gave name to the mastodon 

 found at Newburg, N. Y., 119. 



Water, its com position discovered, 31, 

 34, 253. 



Weather bureaus, their principal oc- 

 cupation, 186, 191. 



Weber, Ernst Heinrich, his experi- 

 ments and discovery in psycho- 

 physics, 409-412. 



Weber, Wilhelm Eduard, makes a 

 practical test of the electric tele- 

 graph, 207 ; his study of the ner- 

 vous system, 405. 



Wedgwood, Josiah, invents the py- 

 rometer, 24. 



Wedgwood, Thomas, his experiments 

 in photography, 2, 5. 



Weismann, August, opposes La- 

 marck's theory of acquired vari- 

 ations in the origin of favored 

 species, 318; elaborates a hypo- 

 thetical scheme of the relations of 

 intracellular units, 455. 



Wells, C. W., his solution of the 

 problem of dew formal ion and of 

 the precipitation of \vatery vapor 

 in any form, 170-172. 



Wells, Horace, the first to administer 

 an anaesthetic in a surgical opera- 

 ation, 369. 



Werner, Abraham Gottlob, the pro- 

 pounder of the Neptunian theory, 

 his belief in the aqueous origin 

 of the solids of the earth's crust, 

 123; his belief in the uniformity of 

 strata over thewhole earth, 136, 137. 



Wilson, Patrick, his theory of dew 

 formation, 171. 



Winds. See Aerial currents. 



Wohler, Friedrich, his synthesization 

 of urea, 265, 266 ; his investigation 

 substantiates the binary theory of 

 Berzelius, 268 ; his discovery of 

 isomerism, 274 ; his important ser- 

 vices to physiology, 346, 347 



Wolff, Kaspar Friedrich, founder of 

 the science of embryology, 36 ; 

 foreshadows the cell theory, 336. 



Wollaston, William Hyde, discovers 

 the identity of galvanism and elec- 



474 



