clxxxii INDEX. 



Sang-ay, ascent of, by Wisse, p. 182 ; description, p. 257259, 424, Notes 364, 383, 

 and ronquidos of, Note 383. 



Schergin shaft near Jakutzk, depth of icy stratum in, p. 44, and Notes 45 and 46. 



Schlagintweit (the Brothers), temperature of springs in the Alps, p. 192193; 

 observations in the Kuenlun mountains, Note 572. 



Schmidt (Julius), on Vesuvius, p. 347, and Notes 421 and 589. 



Schomburgk, p. 82. 



Schwabe, sun's spots, p. 89. 



Senarmont, formation of minerals in veins, &c., p. 205, Note 283. 



Siebold, description of Japanese volcanoes, p. 355 et seq. 



Simonoff, p. 83. 



Smell, sweet or peculiar, in some cases of volcanic action, p. 227228. 



Snow-line on the Cordilleras, Note 330. 



Solfataras, p. 328, 381, 408, and Notes 519, 520 and 555. 



Somerville (Mrs.), p. 67 and Note 88. 



Soufriere of la Guadeloupe, Note 555. 



Springs, thermal, 184206, of vapour and gas, 206221, Notes 289-300; tem- 

 perature of, p. 186, 271276, Notes 256, 282, 284 ; mineral veins formed by, 

 p. 204, Note 283. 



Strokr, p. 200. 



Storms, maffnetic see Disturbances. 



Stioiiiboli, p. 251252. 



Styx, source of the, Note 282. 



Sulphur-springs, p. 203. 



Sun, its connection with terrestrial magnetism, p. 81, 88, and 492, Note 73. 



Taal volcano in the Island of Luzon, p. 241, and Note 337. 



Tahiti, p. 383384. 



Taman, mud-volcanoes of, p. 207, 209. 



Temperature, distribution of, in the crust of the globe, p. 3448, 188197 ; in the 



atmosphere, p. 188 ; in the ocean, p. 195; in Artesian wells, p. 35 ; stratum 



of invariable, p. 38 and 189, and Note 41 ; of springs,p. 185187, 189190; 



in the Alps, 192 ; in Germany and Italy, p. 205206, and Note 284 ; of hot 



springs, p. 198 ; of melting point of granite, Note 464. 

 Teneriffe, height of the Peak of, Note 354. 

 Thermal springs, p. 184206. 

 Thian-schan, volcanic activity in the, p. 337 and 414; connection with the 



Caucasus, p. 340, Note 567. 

 Tolima, Note 368. 



Toluca, ascent of, by Humboldt, p. 387, and Note 531. 

 Trachytes, classification of, p. 429436. 



Trincheras, change of temperature in the hot springs of las, p. 199. 

 Turbaco, volcancitos of, p. 211215, Notes 294, 295. 



Vapour-springs, p. 206-221. 



Vesuvius, p. 181, 346,407410, 445, Notes 557, 558, 588. 



Vidal (Captain), his descriptions and charts of the Azores, Note 308. 



Vinagre, Rio, p. 203. 



Vitruvius, quotations from, p. 408. 



Volcancitos, p. 211. 



Volcanic action, different theories of, p. 169, and Notes 235237 ; ancient descrip- 

 tions of and ideas respecting, p. 224, 227, 260, and. Note 386 ; why more fre- 

 quent near seas, p. 411417. 



