INDEX. 



459 



Moon, extent of our acquaintance with thejOrthoclase, 448. 



surface of the, 418; volcanoes and para- 1 Osomo, volcano of, 274. 



sitic craters, 419 ; Kreil on the magnet- 

 ism of the, 84 ; investigation of the sub- 

 ject by General Sabine, 84. 



Mormons, Great Salt Lake of the, 383. 



Mortero, Cerro del, 302. 



Mosenberg, the, an extinct volcano, 222, 

 227. 



Mosychlos, the mountain, destruction of, 

 328. 



Mouna Loa. See Manna Roa. 



Mountain masses, magnetism of, 154. 



Mountain peaks, comparison of, with the 

 bulging of the earth's surface, 31. 



Mousart (corruption of Muztag), equivalent 

 to Sierra Nevada, 405. 



Moya cones of Pelileo, 166, 207. 



Mud springs of Iceland, 203. 



Mud volcanoes, 207, 255. 



Murchison, Sir R., on eruptive trap masses, 

 329, 451. 



Muriatic acid fumaroles, 397. 



Mutis, apparatus of, 428. 



Naphtha springs, 199. 



Negropont. See Euboja. 



Neptune, connection of, with earthquakes, 



173. 

 New Britain, volcanoes of, 371 

 New Caledonia, volcanic action absent 



from, 372. 

 New Guinea, volcanoes of, 371. 

 New Mexico, barometric levelings in, 380 ; 



list of heights, 382. 

 New Zealand, geology of, 371 ; volcanoes, 



372. 

 Niphon, recorded volcanic eruptions in, 350. 

 Nodes, magnetic, their changes of position, 



102, 104. 

 Noises from volcanoes, differences observed 



in, 250; extraordinaiy distances at which 



heard, 251. 

 Norman, Robert, determines the inclina- 

 tion of the magnetic needle in London, 



58. 

 Northwest America, volcanoes of, 377; 



hypsometry of, 382. 

 No variation (magnetic), points and lines 



of, 55, 59 



Obsidian, 447; its cavities and air-holes, 



449. 

 Oerafa, in Iceland, fearful eruptions of, 



330. 

 Oeynhausen, temperature of the salt spring 



at, 39." 

 Oisans, natural amphitheatre of, its vast 



extent, 220. 

 Oligoclase, 439. 



Olot, extinct volcanoes of, 405. 

 Olympus, Mount, in America, 390. 

 Omato, Volcan de, 271. 

 Ometepec, an active volcano, 259. 

 Orinoco, high temperature of its waters at 



certain seasons, 179. 

 Orizaba, a volcano, measurement of the 



peak of, 239 ; lava field of, 305. 

 Oron, fresh-water lake of, seals found in 



the, 408. 

 Orosi, the volcano, 259. 



Overweg's researches on volcanic phenom- 

 ena in Africa, 334. 



Ovid, volcanic phenomena clearly described 

 by, 219. ' 



Owliyhee. See Hawaii. 



^caya, eruptions of, 262. 

 Jfcific Ocean, the term '' Grand Ocean" 

 improperly applied to the, 378 ; compar- 

 atively small number of active volcanoes, 

 364; grouping of its islands by Dana, 

 365. See, also. South Pacific Ocean, 

 South Sea. 

 PanguipuUi, Volcan de, 274. 

 Papagayos, remarkable storms so called, 



257. 

 Paramagnetism exhibited by oxygen gas, 

 51 ; importance of the discovery, 78, 81, 

 98. 

 Paramos, their elevation and vegetation, 



278. 

 Parasitic craters of the moon, 419. 

 Parinacota, volcano of, 271. 

 Passuchoa, the extinct volcano of, 317. 

 Patricius, the bishop, his theory of central 



heat, 188. 

 Paul, St., volcanic island of, 360. 

 Pele's hair, volcanic glass so called, 367. 

 Pelileo, eruption of the Moya of, 166, 207. 

 Pendulum, vibrations of the, applied to 

 determine the figure of the earth, 23; 

 Sabine's expedition, 26 ; other obsei-vei-s, 

 26 ; the form of the earth not exactly 

 determinable by such means, 29 ; Airy's 

 experiments at Harton, 35. 

 Pentland, his discovery of lava streams in 



the eastern chain of the Andes, 279. 

 Perlite, 323. 



Pertusa, hot springs of, 188. 

 Peru and Bolivia, series of volcanoes of, 



276. 

 Peshan, volcano of, 335, 406. 

 Petermann's notices from Overweg, of vol- 

 canic phenomena in Africa, 334. 

 Peteroa, volcano of, 273. 

 Phaselis, flame of the Chimajra, near, 203. 

 Philippines, volcanoes of the, 232. 

 Phlegraian Fields, ancient descriptions of 



the, 400. 

 Pic de Nethou, the highest summit of the 



Pyrenees, 220. 

 Pic of Timor, formerly an evei"-active vol- 

 cano, 358. 

 Pichincha, remarkable form of, 230; ascent 

 of, by Humboldt, 231 ; visited by Wisse, 

 231; its height, 238. 

 Pichu-Pichu, Volcan de, 271. 

 Pico, the volcano, 236 ; eruptions of other 

 volcanoes in the Azores apparently de- 

 pendent on, 330. 

 Piedmont, trembling of the earth in, 17G. 

 Pilla, on theleucite crystals of Rocca Mon- 



fina, 434. 

 Pisoje, basalt-like columns of, 426. 

 Pithecusse, Bokh on the, 253. 

 Pitt, Mount, in America, 389. 

 Plato, on the Pyriphlegethon, 37, 254 ; on 



the magnetic chain of rings, 51. 

 Polar li"rht. Seo Aurora. 



