456 



INDEX. 



Fogo, volcano of the Ilha do, 249. 



Forbes, on the conductive power of differ- 

 ent rocks, 41. 



Formosa, the tnrning-point of the lines of 

 volcanic elevation in the islands of East- 

 ern Asia, 346 ; its volcanoes, 353. 



Foucault's apparatus for demonstrating the 

 rotation of the earth, 28. 



France, extinct volcanoes of, 22T, 263. 



Franklin on frozen earth in the northwest 

 of America, 50; his Arctic voyages, 65; 

 search for him, 65. 



Franklin's Bay, volcano of, more properly 

 a salse, 391. 



Fredonia, near Lake Erie, springs of in- 

 flammable gag at, 204. 



Fremont's hypsometrical investigations in 

 Northwest America, 383. 



Fremont's Peak, 388. 



French Alps, highest summit of the, 220. 



Frozen earth, its geographical extension, 

 48. 



Fse-7mn. a Chinese magnetic apparatus, 

 52. 



Fuego, Volcan de, described, 262. 



Fumaroles, various classes of, 396; Bun- 

 sen on their products, 396. 



Fummarole of the Tuscan Maremma, 202. 



Fused interior of the earth, 234. 



Galapagos, the, countless cones and ex- 

 tinct craters, 374; pumice not found 

 there, 375. 



Galera Zamba, teiTible eruptions of flames 

 and terrestrial changes at, 208. 



Gandavo, Fray Juan de, explores the cra- 

 ter of Masaya, 247. 



Gas, volcanic exhalations of, inquiry into. 

 412. See, also, Sprin.^s. 



Gauss, his theory of terrestrial magnetism. 

 63. 



Gay-Lussac on the chemical causes of vol- 

 canic phenomena, 163 ; on waves of com 

 motion and oscillation, 165. 



Gemellaro, his estimate of the height to 

 which erupted bodies ascend from ^t- 

 na, 251. 



Geographical distribution of volcanoes, 

 393; an abnormal phenomenon in, no- 

 ticed, 405. 



Geological terms, origin of some, 421. 



Geysers, the, of Iceland described, 191. 



Gilbert, William, lays down comprehen 

 aive views on the magnetic force of the 

 earth, 58. 



Glassy feldspar. See Feldspar. 



Godivel, Lac de la, an extinct volcano. 

 227. 

 ' Gog and Magog, Oriental myth of, 337. 



Gold, believed to be found in volcanoes, 

 248 ; descent into Masaya, in search of 

 it, 248. 



Graham, his observation of the hourly va- 

 riations of the magnetic force, 61. 



Graham Island, temporary formation of, 

 328. 



Grand Ocean, a term for the basin of the 

 South Sea, objected to, 378. 



Granite, Mitscherlich's experiments on the 

 melting point of, 234. 



Greece, has frequently suffered from earth- 



quakes, 170 ; great number of thermal 



springs, 170. 

 Grenelle, the Artesian "Well of, 38. 

 Ground temperature, observations on, 182. 



See, also. Frozen Earth. 

 Guadeloupe, the Soufri6re of, described, 



395. 

 Guagua-Pichincha, its meaning, 231. 

 Gualatieri, volcano of, 271. 

 Guanacaure, a volcano, 260. 

 Guanahuca (Guanegue ?) volcano of, 274. 

 Guettard's observations on extinct volca- 

 noes, 310. 

 Gunung, the Javanese term for mountain, 



282. 

 Gunung Tengger, a volcano in Java, vast 



size of its crater, 284. 

 Guyot of Provins, his mention of the mag-* 



netic needle, 54. 



Hair glass, a volcanic product, 367. 



Hall, Captain Basil, experiments to de- 

 termine the mean temperature of places 

 within the tropics, 42 ; measurement of 

 the volcanoes of Old Guatemala, 262; 

 his admirable description of Sulphur Isl- 

 and, S53. 



Halley's theory of four magnetic poles, 59. 



Hallmann, his classification of springs, 

 196. 



Hansteen on the magnetism of the earth, 

 66. 



Harton, pendulum experiments at, relative 

 to the density of the earth, 35. 



Hawaii, the volcanoes of, described, 369, 



Heat, distribution of, in the interior of our 

 globe, 37 ; hypothesis of the depth of the 

 fused interior of the earth below the 

 present sea-level, 234. 



liecla, the volcano, its aspect, 232; in- 

 frequency of its eruptions, 243 ; how 

 classified by Waltershausen, 330. 



Helena, St., volcanic phenomena of, 331. 



Helen's, St., Mount, a volcano, 390. 



Hell, the cold, of the Buddhists, 189. 



Hephaestos, Volcano, the holy isle of, 244. 



Herefordshire, sedimentary rocks of, 221. 



Hesse, on the volcanoes of Central Ameri- 

 ca, 258. 



Hiera, volcanic phenomena upon, de- 

 scribed by Aristotle, 219. 



Himalayan chain, four highest mountains 

 of the, 271 ; known to the Greeks as the 

 elongated Taurus, 406. 



Hobarton, magnetic observations at, 99. 



Ho-cheu, a volcano, also called Turfan, 

 835. 



Hood, Mount, an extinct volcano, 389. 



Hooker, Joseph, on the hot springs of Mo- 

 may, 891. 



Hopkins on earthqtiakes, 162, 165, 168. 



Horaiy variation of the declination not 

 ascribable to the heat of the sun, 81; 

 maxima and minima, at various mag- 

 netic stations, 107. 



Hornblende and augite, 443. 



Hornitos, low volcanic cones, 176 ; farther 

 notices of them, 298, 303. 



Homos or Hornitos. See Hornitos. 



Horsburgh, description of Barren Island 

 by, 359. 



