INDEX TO VOL, V, 



ABIOH on volcanic phenomena in Ghilan,|Antisana, the colossal mountain, described, 

 169; his views on the Caucasian mount- 311 ; its dikes, 312; lakes, 313. 

 ain system, 201, 383 ; analysis of the Antuco, volcano of, 273. 



Chlmborazo rock, 431. 

 Aconcagua, volcano of, measurement of, 



273. 



Acosta on the volcancitos of Turbaco, 205. 

 Adams, Mount, a volcano, 390. 

 ^Enaria, the island of Apes, 252. 

 ^Eolus, residence of, on Strongyle, 244. 

 yEtna, eruptions of, usually occur within a 



Aphron, the northern pole of the mag- 

 netic needle, 54. 



Apparatus employed by Humboldt for hia 

 453 determinations of height in the New- 

 World, 428. 



Arabia, lava eruptions in, 336. 



Arago on magnetic inclination, 105; hia 

 series of magnetic observations, 75. 



pace of six years, 243; periods of its Aiarat, as a volcano, 339, 



greatest activity, 244; height to which 

 ejected matters attain, 251; its trach- 

 ytes, 434. 



Arare, crater of, 368. 

 Arequipn, volcano of, 270. 

 Argseus, the volcano, 237. 



Africa, determination of the magnetic Arimer, country of the, 252. 



equator in, by Sabine, 102 ; ita transla- 

 tion,^; snowy mountains in, 333; vol- 

 canoes in, 332 ; their small number, 334. 



African magnetic node, its varying posi- 

 tion, 102. 



Agaschagokh, island of, 348. 



Agreeable odor diffused from certain vol- 

 canoes, 219. 



Agua, Volcan de, described, 262. 



Airy, density of the earth determined by, 

 35 ; on terrestrial magnetism, 79. 



Alaid, great eruptions of the volcano on 

 the isle of, 349. 



Albite, 438. 



Aleutian islands, numerous volcanoes in, 

 347. 



Alps, temperature of spi-ings in the, 184. 



America. See Central America, Chili, 

 Mexico, Northwest America, Peru and 

 Bolivia, Rocky Mountains, South Sea. 



Ampere on the cause of earthquakes, 162. 



Ampolletas, 57. 



Amsterdam, volcanic island of, 3GO. 



Anahuac, series of volcanoes of, 266. 



Anaxagoras, maxim of, verified, 11. 



Andaman isles, volcanic phenomena in the, 

 359. 



Andes, large spaces in the chain of, desti- 

 tute of volcanoes, 267; groups and dis- 



three Cordilleras, 276. 

 Andesite, 437, 439. 

 Andrea Bianco, his early charts exhibit 



the magnetic variation, 55. 

 Anemasite, 446. 

 Annular valleys, 221. 

 Ansango, lake of, 313. 

 Ansogorri, Father Joaquin, his description Banda, a volcanic island^ 357. 



of the rise of the volcano Jorullo, 292. iBarba, the volcano, described, 259. 

 Ant-hills in the Rocky Mountains, their Barile, earthquake at, 167. 



remarkable construction, 443. 



Aristotle on the fundamental principles of 

 nature, 9; volcanic phenomenon upon 

 Hiera described by, 219. 



Arran, volcanic phenomena in, 329. 



Artesian wells, Walferdin's observations 

 on, 38. 



Ascension, volcanic phenomena of the isl- 

 and of, 331. 



Asia, situation of the principal volcanoes 

 in, 281 ; volcanoes of the western and 

 central parts, 334; of Kamtschatka, 340 ; 

 of the islands of Eastern Asia, 344 ; of 

 the islands of Southern Asia, 354; of the 

 Indian Ocean, 358. 



Atlantic Ocean, volcanoes of the islands 

 of the, 330; presumed submarine vol- 

 cano, 332. 



Atlantis of Solon, 173. 



Atolls, or lagoon reefs, 363. 



Attraction of the magnet known to the 

 Greeks and Romans, 51. 



Augite, 443. 



Aurora Borealis, 147 ; observations of the 

 black segment, 148; colors observed in 

 high latitudes, 149 ; accompanying fleecy 

 clouds, 150 ; influence on terrestrial mag- 

 netism, 152 ; observations at Berlin and 

 at Edinburgh, 153. 



Auvergne, extinct volcanoes of, 227, 263. 

 tances, 268 ; special direction of the Azores, craters of elevation in the, 217 ; 



the volcano of Pico, 236. 

 Azufral de Quindiu, Humboldt's visit to 

 the, 211; change of temperature ob- 

 served by Boussingault, 212. 



Baily on the density of the earth, 34. 

 Baker, Mount, a volcano, 390. 



Antilles, Little, volcanoes of the, described, 

 394. 



Barrancos on the slopes of volcanoes, 



287. 

 I Barren Island, one of the Andaman*, ap- 



