TRUE VOLCANOES. 327 



prolongation of the lava-stream which is certainly very pro- 

 bable (it is so represented in my Profiles tab. 9 and 11, and 

 in the Nivellement Barometrique), that it may have flowed 

 from this mountain, the form of which is so remarkable. 

 The Cofre de Perote, which is nearly 1400 feet higher than 

 the peak of Teneriffe, but inconsiderable in comparison with 

 the giants Popocatepetl and Orizaba, forms, like Pichincha, 

 a long rocky ridge, upon the southern extremity of which 

 stands the small cubical rock (la Pen a), the form of which 

 gave origin to the ancient Aztec name of Nauhcampatepetl. 

 In ascending the mountain I saw no trace of the falling in 

 of a crater, or of eruptive orifices on its declivities ; no 

 masses of scoriae, and no obsidians, perlites or pumice-stones 

 belonging to it. The blackish gray rock is very uniformly 

 composed of much hornblende and a species of felspar, which 

 is not glassy felspar (sanidinr) but oligoclase ; this would 

 show the entire rock, which is not porous, to be a dioritic 

 trachyte. I describe the impressions which I experienced. 



forest-trees in beautiful pine-trees : Pinus occidentalis, mixed with 

 Cupressus sabinoides and Arbutus Madrono. The oak, Quercus xala- 

 pensis, had accpmpanied us only to an absolute elevation of 10,340 

 feet. (Humboldt, Nivellement barometr. des Cordilleres, Nos. 414 

 429). The name of Nauhcampatepetl, which the mountain bears in 

 the Mexican language, is derived from its peculiar form, which also 

 induced the Spaniards to give it the name of Cofre. It signifies 

 " quadrangular mountain" for nauhcampa, formed from nahui, the 

 numeral four, signifies, as an adverb from four sides, but as an adjec- 

 tive (although the Dictionaries do not state this), undoubtedly quad- 

 rangular or four -sided, as this signification is attached to the com- 

 pound nauhcampa ixquich. An observer, very well acquainted with 

 the country, M. Pieschel, supposes the existence of an old crater- 

 opening on the eastern declivity of the Cofre de Perote (Zeitschrift 

 filr Allgem. Erdkunde, herausg, von Gumprecht, Bd. v, s. 125). I 

 drew the view of the Cofre, given in my Vues des Cordilleres, pi. xxxiv, 

 in the vicinity of the castle of San Carlos de Perote, at a distance of 

 about eight miles. The ancient Aztek name of Perote was Pinahui- 

 zapan, and signifies (according to Buschmann) the beetle pinaJiuiztli 

 (regarded as an evil omen, and employed superstitiously in fortune- 

 telling : see Sahagun, Historia Gen. de las Cosas de Nueva Espana, 

 t. ii, 1829, pp. 10 11) on the water ; the name of this beetle is derived 

 from pinahua, to be ashamed. From the same verb is derived the 

 above-mentioned local name Pinahuast (pinahuaztli) of this district; 

 as well as the name of a ehrub (Mimosaceae '?) pinahuihuiztli, trans- 

 lated herba verecunda by Hernandez, the leaves of which fall down 

 when touched. 



