336 TRAVELS A3fONGST THE GREAT ANDES, chap. xix. 



and at various elevations, and the nearest mountains on the eastern 

 side occur at irregular distances. There is no such thing as one 

 great valley in the interior of Ecuador. The mountains Pasochoa 

 and Euminahui are the only two which lie i^arallel to the others 

 on the western side.^ 



The main chain of the Andes was created by upheaval at some 

 remote date, but no one can say when this movement occurred, or 

 whether it was an affair of a year or was spread over thousands of 

 years. All of the Great Andes of the Equator rise out of, or upon 

 and above the main chain. ^ With the excej)tion of Sara-urcu, 

 they are all mountains of volcanic origin,^ although they may 

 not all have been active volcanoes. There will possibly be, for 

 a long time to come, a diversity of opinions as to the manner 

 of their formation. It seems to me probable that there were 

 never many of these volcanoes in activity at any one moment. 

 Some that are now extinct have evidently been alive ; while 

 others, like Pichincha and Tunguragua, are either dormant or are 

 not perpetually in eruption. Cotopaxi and Sangai alone are in 

 a state of constant activity, and these two mountains seem to 

 be increasing their elevation.'' 



* The Pacific Range of Ecuador and the range running south from Chimborazo as 

 far as the Rio Chanchan are, however, parallel to each other ; and the course of the 

 River Chimbo, from Guaranda to Chimbo, runs through a valley, speaking properly. 

 I have already endeavoured to make it clear that this Pacific Range lies outside 

 the main chain of the Andes. It has nothing to do with the " two parallel 

 Cordilleras." 



2 The elevation of the range in general, in Ecuador, although considerable, is not 

 so great as it is farther to the south ; and a railway might be carried there across the 

 chain at a lower level than the Trans -Andean line which is at present being con- 

 structed to connect Buenos Ayres with Valparaiso. 



3 In Ecuador, the rocks that were previously at the surface are now almost 

 entirely buried under lavas or volcanic-dusts, which have welled out of fissures or 

 have been violently ejected. 



4 The excellent observers M. de la Condamine, and the Doctors Reiss & Stiibel 

 measured Cotopaxi and Sangai at an interval of 130 years. The former found the 

 height of Cotopaxi was 18,865 feet, and Sangai 17,139 feet. The latter found the 

 heights were 19,498 and 17,464 feet respectively. 



