270 



PLATEAU OF CAXAMA11CA. 



good deal flattened by rotation, but also sometimes of less 

 regular forms, the hail having run together into thin plates of 

 ice (papa-cara) which cut the face and hands. At such times 

 I have occasionally seen the thermometer sink to 7 or 5 

 Reaumur, (47.8 and 43. 2 Eahr.) and the electric tension of 

 the atmosphere, measured by Volta's electrometer, pass in a 

 few minutes from positive to negative. "When the temperature 

 sinks below 5 Reaumur, (43.2 Fahrenheit) snow falls in large 

 and thinly scattered flakes. The vegetation of the Paramos 

 has a peculiar physiognomy and character, from the absence 

 of trees, the short close branches of the small-leaved myrtle- 

 like shrubs, the large sized and numerous blossoms, and the 

 perpetual freshness of the whole from the constant and 

 abundant supply of moisture. . No zone of Alpine vege- 

 tation in the temperate or cold parts of the globe can well be 

 compared with that of the Paramos in the tropical Andes. 



The impressions produced on the mind by the natural 

 characters of these wildernesses of the Cordilleras are height- 

 ened in a remarkable and unexpected manner, from its 

 being in those very regions that we still see admirable 

 remains of the gigantic work, the artificial road of the 

 Incas, which formed a line of communication through all 

 the provinces of the Empire, extending over a length of 

 more than a thousand English geographical miles. We 

 find, placed at nearly equal distances apart, stations con- 

 sisting of dwelling houses built of well-cut stone ; they are 

 a kind of Caravanserai, and are called Tambos and some- 

 times Inca-pilca (from pircca, the wall?). Some of 

 them are, surrounded by a kind of fortification ; others were 



