124 M, Humboldt on Volcanoes, [Aug. 



limestone, but never occur in narrow streams which have flowed. 

 Similar evidences of former revolutions may be found in many 

 parts of the Grecian continent, and in Asia Minor, countries 

 which will afford the geognost copious subjects for examination, 

 ■when the hght once returns to the land whence it first beamed 

 over the western world — when tormented mankind ceases to 

 sink under the savage lethargy of the Ottoman. 



I mention the geographical neighbourhood of so many phaeno- 

 mena, in order to prove, that tne bed of the Mediterranean, 

 with all its chains of islands, might have afforded to the atten- 

 tive observer, every thing that has been discovered, in latter 

 periods, under the most varied forms, in South America, on 

 TenerifTe, or on the Aleutian islands, near the polar regions. 

 There were accumulated objects for observation, but tours into 

 distant regions, and the comparison of large tracts of country 

 within and beyond Europe, were necessary, in order to discover 

 what was common to all these phaenomena, and to learn, 

 clearly, their dependence on each other. 



By the usage of language, which often gives stability and 

 respect to the first erroneous views of things, but often, as it 

 were, by instinct, distinguishes the truth, we apply the term 

 volcanic to all eruptions of subterranean and melted matter ; to 

 columns of smoke and steam, which rise sporadically out of 

 rocks, as at Colares after the great earthquake at Lisbon ; to 

 Salsae, or conical hills of clay which emit mud, asphaltum, and 

 hydrogen, as those near Girgenti, in Sicily, and near Turbaco, 

 in South America ; to hot Geyser springs which rise by the 

 pressure of elastic vapours ; and, in general, to all violent powers 

 of nature which have their seat deep in the interior of our planet. 

 In the Spanish main of America, and in the Phihppine islands, 

 the inhabitants make a distinction between igneous and aqueous 

 volcanoes, vulcanes de aguay defuego: they apply the first name 

 to mountains, which, during violent earthquakes, from time to 

 time, eject subterraneous water, and with a dull noise. 



Without denying the connexion between the different pheno- 

 mena just mentioned, it seems advisable to give a distinct 

 language to the physical as well as to the oryctognostic branch 

 of geognosy ; and not to apply the term volcano in one instance 

 to a mountain that terminates in a permanent crater ; and in 

 another, to every subterranean cause of volcanic phaenomena. 



In the present state of the earth, the most common form of 

 volcanic eminences is that of isolated cones ; such are Vesuvius, 

 iEtna, the Peak of Teneriffe, Tunguragna, and Cotopaxi. I 

 have seen them of every magnitude, from the lowest hills to 

 mountains rising to the height of 17,700 feet above the level of 

 the sea. Besides these conical mountains, there are other cra- 

 ters, permanently communicating with the interior of the earth, 

 situated upon lengthened craggy ranges of mountains, not 

 always in the middle of their wall-like summits, but towards the 

 end^ and near their declivities. Such is Pichincha wliich lises 



