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PLATKORMS OF THE ANDES. 



General 

 elevation. 



Plains of 



South 



America. 



cnAP.xxiV. St Beniard of the Swiss Alps ; and to determine this 

 circumstance Humboldt executed five laborious barome- 

 trical surveys, whicli enabled him to construct a series 

 of vertical sections of the country. 



In South America the cordillera of the Andes presents 

 plains completely level at immense altitudes, such as 

 that on vi'hich the city of Santa Fe de Bogota stands, 

 that of Caxamarca in Peru, and those of Antisana, which 

 exceed in height the summit of the Peak of TeneriflPe. 

 But all these levels are of small extent, and being sepa- 

 rated by deep valleys are of difficult access. In Mexico, 

 on the other hand, vast tracts of champaign country are 

 so approximated to each other as to form but a single 

 plain occupying the elongated ridge of the cordillera, 

 and running from the 18th to the 40th degree of north 

 latitude. The descent towards the coasts is l)y a gra- 

 duated series of terraces, which oppose great difficulties 

 to the communication between the maritime districts 

 and the interior, presenting at the same time an extra- 

 ordinary diversity of vegetation. 



Tlie jdains along the coasts are the only parts that 

 possess a climate adapted to the productions of the 

 West Indies, — the mean temperature of those situated 

 \vithin the tro])ics, and whose elevation does not exceed 

 084 feet, being. from 77° to 78-8^, which is several 

 degrees greater than the mean temperature of Naples. 

 These fertile regions, which produce sugar, indigo, 

 cotton, and Ijananas, are named Tierras calientes, Euro- 

 peans remaining in them for any considerable time, 

 particularly in the towns, are liable to the yellow fever 

 or black vomiting. On the eastern shores tlie great 

 heats are occasionally tempered by strata of refrigerated 

 air brouglit from the north by the impetuous winds 

 tliat blow from October to March, which frequently cool 

 the atmosphere to such a degree, that at Havannah the 

 thermometer descends to 32°, and at Vera Cruz to 

 60-8°. 



On the declivities of the cordillera, at the elevation of 

 3937 or 4021 feet, there prevails a mild climate, never 



Climate 

 along the 

 coasts. 



