499 



Telica, Volcan de, described, 274. 



Telluric phenomena, special re- 

 sults of observation in the do- 

 main of, 1. 



Temboro, a volcano, its violent 

 eruption, in 1815, 381. 



Temperature, invariable, stratum 

 of, 39 ; mean annual, how de- 

 termined in the tropics, 40; 

 observations of, in Mexico and 

 Peru, by Humboldt, 41 ; frozen 

 soil in Northern Asia, 42; 

 Schergin's shaft, 43. See Interior 

 of the Earth. 



Temperature, rise of, in springs, 

 during earthquakes, 175. 



Teneriffe, the felspar of the tra- 

 chytes of, 457; notice of an erup- 

 tion on, by Columbus, 477. 



Ternate, violent eruptions and 

 lava streams in, 381. 



Tertiary formations in Java, 298. 



Thermal springs, their connexion 

 with earthquakes, 177. 



Thian-schan, the volcanic moun- 

 tain chain of, 358 ; peculiarity 

 of the position of the volcano, 

 433 ; the chain known to the 

 Greeks as the elongated Taurus, 

 434. 



Thibet, hot springs of, 197; gey- 

 sir, 199. 



Tierra del Fuego, volcanoes of, 

 296. 



Timor, Pic of, formerly an ever- 

 active volcano, 382. 



Tollo, the pumice hill of, 481. 



Tonga Islands, active volcanoes of 

 the, 394. 



Toronto, magnetic observations 

 at, 100. 



Trachyte, origin of the word, 450; 

 frequently used in too confined 

 a sense, 452; further remarks, 

 468. 



Tractus chalyboeliticos, what, 59. 



Translatory movements in earth- 

 quakes, 173. 



Trap, masses of, Sir R. Murchison 

 on, 350, 483. 



Trass, formation, 236. 



Trincheras, hot springs of, 197. 



Tristan da Cunha, a volcanic 

 island, 353. 



Tshashtl mountains, basaltic lavas 

 of the, 416. 



Tucapel, volcano of, 289. 



Tupungato, measurement of the 

 peak of, 289. 



Turbaco, the Volcancitos of, 213. 



Tuscan Maremma, volcanic pheno- 

 mena of the, 211. 



Typhon, fable of, 266. 



Umnack, volcanic island of, 230. 



Unalavquen, volcano of, 290. 



Under currents of cold water in 

 the tropics, 194. 



United States' scientific expedi- 

 tions, benefits to natural history 

 from the, 404. 



Uvillas or Uvinas, Volcan de, 286. 



Val del Bove, on Etna, remarkable 

 inference regarding, 225. 



Valleys of elevation, what, 201. 



Vancouver, Mount, 417. 



Vapour and gas springs, 222. 



Variation charts, their early date, 

 54. 



Vegetation, limit of. in Northern 

 Asia, 43. 



Vesuvius, phenomena of an erup- 

 tion of, as observed by Hum- 

 boldt, 181; barometrical mea- 

 surements by the same, 247 ; 

 lengthened series of eruptions 

 of, 426; described by Strabo, 

 426; by Dio Cassius, 427; by 

 Diodorus Siculus, 428 ; by 

 Vitruvius, 428 ; difference of 

 constitution of the old and the 

 recent lavas, 477 ; encampment 

 of Spartacus and his gladiators 

 on, 427. 



Vesuvius, valley furrows on the 

 mantle of the Somma of, 305. 



Vidua, Count Carlo, his melan- 

 choly death, 381. 



Vilcanoto, peak of, 296. 



