464 



the eastern part, 1340 toises ; and in the western 

 part 1490 toises ; the basin of Alinaguer 1160 

 toises ; the basin * of the Rio Cauca, between 

 the lofty plains of Cali, Buga, and Cartago, 500 

 toises ; the valley of Magdalena, first between 

 Neiva and Honda, 200 toises ; r and further on, 

 between Honda and Mompox, 100 toises of 

 mean height above the level of the sea*f~. In 



be geognostically considered as the same valley as that of 

 Puembo and Chillo. The interposed hills of Ichimbio and 

 Poingasi mask this communication. 



* In order to compare this basin, which is the most fer- 

 tile part of the province of Popayan, and the basin of the 

 Magdalena with those of the ancient continent, I shall here 

 mention the table-lands of Mysore in India (420 to 470 

 toises) 5 the interior of Spain (350 toises) y of Switzerland 

 between the Alps and the Jura (270 toises) ; of Bavaria (260 

 toises), and of Swabia (150 toises). 



+ In the region of the Andes comprehended between 4° of 

 south latitude and 2° of north, the longitudinal tallies, or 

 basins inclosed by parallel chains, are regularly between 

 1200 and 1500 toises high ; while the transversal vallies are 

 remarkable for their depression, or rather the rapid lower- 

 ing of their bottom. The valley of Patias, for instance, 

 running from N. E. to S. W. is only 350 toises of absolute 

 height even above the junction of the Rio Guachicon with 

 the Quilquasi, according to the barometric measures of Mr. 

 Caldas j and yet it is surrounded by the highest summits, the 

 Paramos de Puntaurcu and Mamacondy. (Seman. Tom. i, 

 p. 28, and Tom. ii, p. 140.) In going from the plains of 

 Lombardy, and penetrating into the Alps of the Tyrol, by a 

 line perpendicular to the axis of the chain, we advance more 

 than 20 marine leagues towards the north, yet we find the 



