( 350 ) 



On the Heights of the most remarTcahle Summits of the CordU- 

 lera of ike Andes in Peru, 



1 o know the highest sutnmtt in every chain of mountains, the 

 highest mountain in every country, in every continent, in the 

 whole world, has always been a favourite object with mankind. 

 Astronomical observations have permitted this research to be 

 extended even to the Moon, to Mercury and Venus. These 

 planets have been studied of late with so much care, and with 

 instruments so powerful, that it seems difficult to determine 

 more precisely than has already been done, the height of the pro- 

 digious mountains which cover their surface. The asperities of 

 the Earth have also been the objects of constant research. The 

 number of points whose several heights above the level of the 

 sea, are irrevocably fixed, is very considerable ; and yet, not to 

 mention countries which geographers have never yet explored, 

 it would be difficult to say with certainty, even of the Hima- 

 laya, Caucasus, the American ranges, and even of some chains 

 in Europe, whether their culminating points have been accu- 

 rately measured. Not but that the traveller may have, in every 

 place, directed his attention to the summits which apjyeared to 

 him the highest ; but unfortunately such appearances are often 

 deceitful, and bad substitutes for real measurements. The cir- 

 cumstance of a mountain being more or less isolated, the incli- 

 nation of its sides, its distance, the form, disposition and height 

 of the surrounding grounds, and finally the state of the atmo- 

 sphere, are so many causes of fallacy, from which the most ex- 

 perienced observer cannot get free, and which are removed only 

 by the barometer and geodesical instruments. Were it necessary 

 to adduce examples in support of these reflections, many might 

 be quoted. Thus we might say that, at the beginning of the 

 eighteenth century, the Peak of TenerifFe was reckoned the 

 highest mountain in the world *, though, in the Alps of Switzer- 

 land, there were summits which surpass it nearly one-third; 

 though many travellers had, on their return from Peru, seen 

 the great Cordillera of the Andes, and even visited some of 

 the populous towns that are situated on their table-lands, whose 

 * See the Geography of Vareniiis, reviewed by Newton. 



