372 



NATURAL PHENOMENA OF THE EQUATORIAL REGION*. 



Tin in on the 

 west. 



Chirnbornzo. 

 Its height. 



Vast volcano. 



The east face 

 of the Andes 

 steepest. 



Geography of 

 plants.. 



Variation of 

 temperature. 



Cold of the 

 Andes. 



Feai near the 

 rivcis. 



From the western shore of America, in this region, to the 

 chain of the Cordilleras, we find a plain stretching a consi- 

 derable distance from north to south, but in no place ex- 

 ceeding twenty or thirty leagues in breadth. Chimborazo, 

 the loftiest summit of the vast chain of the Andes, rises in 

 l p 27' south lat itudc. From the author's barometrical mea- 

 surements, calculated by the formula of Mr. Laplace, this 

 mountain is 6536 met. [7143 yards] above the level of the 

 sea. Mr. Condamine gives 180 met. [197 yards] less: a 

 difference naturally arising from his neglecting the temper- 

 ature. 



In the map accompanying this volume, where Mr. von 

 H. has given a vertical plan of Chimborazo, the summit of 

 Cotopaxi appears behind it; a volcano nearly five times as 

 high as Vesuvius, and the roarings of which were heard in 

 1744 to the distance of 220 leagues. 



Several eminent natural philosophers have supposed, that 

 the western slope of the Andes was much steeper than that 

 on the cast: but Mr. von Humboldt has found the contrary 

 to be the case, after traversing the chain in several directions. 



The part which the author has dedicated to the geogra- 

 phy of plants exhibits many new views. On the plain of 

 Chimborazo he has inserted the names of the plants growing 

 on it at different heights, which he determined accurately by 

 means of the barometer. His comparison of them with 

 the plants growing at the same heights on the Alps and Py- 

 renees is extremely curious: and he has noted the height 

 they attain, according to the different situations aud ele- 

 vations where they grow. 



This article is followed by a series of observations on 

 every thing that varies with the heights to which you ascend 

 above the level of the sea. The table of variations of tem- 

 perature exhibits the maximum and minimum of heat, which 

 the centigrade thermometer indicates from five metres to 

 five hundred. It appears, that the cold of the Andes is not 

 very considerable; but- many circumstances combine to 

 render it difficult to bear On Chimborazo, at the height 

 of £908 met. [6457 yards], the thermometer descends only 

 to —1-8° [28-76° F.]. In the hottest regions on the 

 fcanks of the Amazon, Magdalena, and other rivers, the 



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