WESTEBN CHAIN OF T1IE ANDES. 



10 3 and 5, no summit of the eastern and central chains rises 

 as high as the region of perpetual snow; the only snowy 

 summits are in the western chain. The central chain, that 

 of the Paramos de Callacalla, and Piscoguanuna, scarcely 

 attains 1800 toises, and lowers gently to 800 toises; so that 

 the mountainous and temperate tract of country which 

 extends on the north of Chachapoyas towards Pomacocha, 

 La Vellaca, and the source of the Rio Nieva, is rich in fine 

 cinchona trees. After having passed the Rio Huallaga and 

 the Pachitea, which with the Beni forms the Ucayali, we 

 find, in advancing towards the east, only ranges of hills. 

 The western chain of the Andes, which is the most elevated 

 and nearest to the coast, runs almost parallel with the shore 

 N. 22 W., between Caxatambo and Hilary, Conchucos and 

 Guamachuco, by Caxamarca, the Paramo de Yanaguanga, 

 and Montan, towards the Rio de Guancabamba. It comprises 

 (between 9 and 7) the three Nevados de Pelagatos, Moyo- 

 pata, and Huaylillas. This last snowy summit, situated near 

 Guamachuco, (in 7 55' lat.) is the more remarkable, since 

 from thence on the north, as far as Chimborazo, on a length 

 of 140 leagues, there is not one mountain that enters the 

 region of perpetual snow. This depression, or absence of 

 snow, extends in the same interval, over all the lateral chains ; 

 while, on the south of the Nevado de Huaylillas, it always 

 happens that when one chain is very low, the summits of the 

 other exceed the height of 2460 toises. It was on the south 

 of Micuipampa (lat. 7 1') that I found the magnetic equator. 

 The Amazon, or as it is customary to say in those 

 regions, the Upper Maranon, flows through the western part 

 of the longitudinal valley lying between the Cordilleras of 

 Chachapayas and Caxamarca. Comprehending in one point 

 of view, this valley, and that of the Bio Jauja, bounded by 

 the Cordilleras of Tarma and Huarocheri, we are inclined to 

 consider them as one immense basin 180 leagues long, and 

 crossed in the first third of its length, by a dyke, or ridge 

 18,000 toises broad. In fact, the two alpine lakes of Lauri- 

 cocha and Chinchaycocha, where the river Amazon and the 

 Rio de Jauja take their rise, are situated south and north of 

 this rocky dyke, which is a prolongation of the knot of 

 Huanuco and Pasco. The Amazon, on issuing frdm the 

 longitudinal valley which bounds the chains of Caxamarca 



