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LX. Afemoir on a new Species of Piinelodus thrown out oj 

 the Volcanoes in the Kingdom of Qn'tto ; with some 

 Particulars respecting the Folcanoes of the Andes. By 

 M. De Humboldt *. 



X HE chain of the Andes, from the Straits of Magellan to 

 the northern shores bordering on Asia, extending over more 

 than 2000 leagues, presents above fifty volcanoes still active, 

 of which the phaenomena are as various as their height and 

 local situation. A small number of the least elevated of 

 these volcanoes throw out running lava. I have seen, at 

 the volcano of Zurnllo, in Mexico, a basaltic cone that 

 sprung from the earth the 15lh September 1759, and at 

 present rising 249 toises {15955- feet) above the surrounding 

 plain. The volcanic ridges of Guatimala cast out a prodi- 

 gious quantity of muriate of ammonia. Those of Popayan 

 and the high plain of Pasto present either solfatarcs, which 

 exhale sulphureous acid, or little craters filled with boiling 

 water, and disengaging sulphurated hydrogen, which de- 

 composes by contact with the oxygen of the atmosphere. 

 The volcanoes of the kingdom of Quito throw out pumice- 

 stone, basahesf, and scorified porphyries ; and vomit enor- 

 mous quantities of water, carburetted argil, and muddy mat- 

 ter, which spreads fertility from eight to ten leagues around. 

 But, since the period to which the traditions of the natives 

 ascend, they have never produced great masses of running 

 melted lava. The height of these colossal mountains, that 

 surpasses five times that of Vesuvius, and their inland situa- 

 tion, are, without doubt, the principal causes of these ano- 

 malies. The subterranean noise of Cotopaxi, at the time 

 of its creai explosions, extends to distances equal to that 

 from Vesuvius to Dijon. But, notwilhstaading this mten- 



* ¥rom Rccucil d'Ohirvutions <le Zoologie et d'Anatomie cowfpan', Irclivraison. 



t It Would have been of some use to geology had the author here men- 

 tioned whether the stone which he calls basaltes has been submitted to 

 the action of fire or water ; or whether, in adaition to the other well known 

 characters of this n\incral, it yielded hydrogen gas on dijtiiiaiion, the latter 

 being the pccuUar characteristic of what is properly deaominatcd basalies. — 

 Ira/istator. 



sity 



