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in the higher Alps. On advancing from Po- 

 payan toward the south, we see on the arid ele- 

 vated plain of the province of Los Pastos the 

 three small chains of the Andes lost in one 

 group, which stretches far beyond the equa- 

 tor. 



This group, in the kingdom of Quito, pre- 

 sents an extraordinary appearance from the 

 river of Chota, which meanders amid moun- 

 tains of basaltic rock to the Paramo of Assuay, 

 on which are seen some remarkable remains of 

 Peruvian architecture. The most elevated sum- 

 mits are arranged in two lines, which form as 

 it were a double ridge to the Cordilleras. These 

 colossal summits, covered with perpetual ice, 

 served for signals in the operations of the French 

 academicians at the time of the measurement 

 of the equinoxiai degree. Their symmetrical 

 disposition, in two lines directed from north to 

 south, has led Bouguer to consider them as 

 two chains of mountains, separated by a longi- 

 tudinal valley : but what this celebrated astro- 

 nomer calls the bottom of a valley is the summit 

 of the Andes itself ; it is an elevated plain, the 

 absolute height of which is from two thousand 

 seven hundred to two thousand nine hundred 

 metres. We must not confound a double 

 ridge with a real ramification of the Cordil- 

 leras. 



The plain covered with pumice stone, that 



