ON ITS EXTERIOR. VOLCANOES. 271 



middle of the narrow high plain), the Altar de los 

 Collanes (Capac-Urcu), and Sangay on the eastern one. 

 If we embrace the whole northernmost group of South 

 American volcanoes in one view, the opinion, often ex- 

 pressed in Quito and in some measure supported by 

 historic accounts, of a migration of the greater intensity 

 of volcanic activity to the southward, will seem to 

 acquire some degree of probability. It is true, on the 

 other hand, that in the south, by the side of the well 

 nigh incessantly active colossal Sangay, we find the 

 ruins of the " prince of mountains " Capac-Urcu, said 

 to have surpassed Chimborazo in height, but which in 

 the latter part of the fifteenth century (fourteen years 

 before the conquest of Quito by the son of the Inca 

 Tupac Yupanqui) fell in, became extinct, and has not 

 since^been rekindled. 



The area not covered by groups of volcanoes in the 

 Andes, is far greater than is commonly supposed. In 

 the northern part of South America, from the Volcan 

 de Euiz and the cone of Tolima, the two northernmost 

 volcanoes of the New Granada and Quito series, to 

 beyond the Isthmus of Panama, about Costa Eica, where 

 the Central American series begins, there extends a 

 region of more than 600 geographical miles in length, 

 which is, indeed, often powerfully agitated by earth- 

 quakes, and which contains flame-emitting salses, but 

 in which true volcanic eruptions are not known. On 

 the south, a still longer tract in which there are no 

 volcanoes extends nearly 1000 miles, from Sangay, 

 the southern extremity of the New Granada and Quito 

 group, to Chacani near Arequipa, the commencement of 

 the Peru and Bolivia series of volcanoes. So compli- 



