TRUE VOLCANOES. 275 



because, when observed from the plain, the thin vapors, which 

 ascend from the crater at a great height, remain invisible to 

 the eye. Thus it was even denied, at the time of my Amer- 

 ican travels, that Pichincha and the great volcano of Mexico 

 (Popocatepetl) were still active, although an enterprising 

 traveler, Sebastian Wisse,* counted 70 still burning orifices 

 (fumaroles) around the great active cone of eruption in the 

 crater of Pichincha ; and I was myself a witness,! at the 

 foot of the volcano in the Malpais del Llano de Tetimpa, in 

 which I had to measure a base-line, of an extremely distinct 

 eruption of ashes from Popocatepetl. 



In the series of volcanoes of New Granada and Quito, 

 which in 18 volcanoes includes 10 that are still active, and 

 is about twice the length of the Pyrenees, we may indicate, 

 from north to south, as four smaller groups or subdivisions : 

 the Paramo de Ruiz and the neighboring volcano of Tolima 

 (latitude, according to Acosta, 4° 55 / N.) ; Purace and Sota- 

 ra, near Popayan (lat. 2^°) ; the Volcanes de Pasto, Tuquerres 

 and Cumbal (lat. 2° 20' to 0° 50') ; and the series of volca- 

 noes from Pichincha, near Quito, to the unintermittently act- 

 ive Sangay (from the equator to 2° S. lat.). This last sub- 

 division of the active group is not particularly remarkable 

 among the volcanoes of the New World, either by its great 

 length or by the closeness of its arrangement. We now 

 know, also, that it does not include the highest summit ; for 

 the Aconcagua in Chili (lat. 32° 390 of 23,003 feet, accord- 

 ing to Kellet, 23,909 feet, according to Fitzroy and Pent- 

 land, besides the Nevados of Sahama (22,349 feet), Parincota 

 (22,030 feet), Gualateiri (21,962 feet), and Pomarape (21,699 

 feet), all from between 18° V and 18° 25 / south latitude, 

 are regarded as higher than Chimborazo (21,422 feet). Nev- 

 ertheless, of all the volcanoes of the New Continent, the 

 volcanoes of Quito enjoy the most widely-spread renown, for 

 to these mountains of the chain of the Andes, to this high 

 land of Quito, attaches the memory of those assiduous astro- 

 nomical, geodetical, optical, and barometrical labors, directed 

 to important ends, which are associated with the illustrious 

 names of Bouguer and La Condamine. Wherever intellectu- 

 al tendencies prevail, wherever a rich harvest of ideas has 

 been excited, leading to the advancement of several sciences 

 at the same time, fame remains, as it were, locally attached 



* Humboldt, Kleinere Sch?-iften, bd. i., s. 90. 



f 24th of January, 1804. See my Essai Politique sur la Xouvelle 

 Espagne, t. i., p. 166. 



