418 



height at Chili of the lower limit of snow, in 

 the 33° of south latitude. The limit does not 

 lower in summer to 2000 toises *. I think we 

 may conclude, according to the analogy of the 

 snowy mountains of Mexico and southern Eu- 

 rope, and considering the difference of the 

 est hale temperatures of the two hemispheres, 

 that the real Nevadas at Chili, in the parallel 

 of Valdivia (lat. 40°), cannot be below 1300 

 toises ; in that of Valparaiso (lat. 33°) not 

 lower than 2000 toises, and in that of Copiapo 

 (lat. 27°) not below 2200 toises of absolute 

 height. They are the limit numbers, the mini- 

 mum of elevation, which the ridge of the Andes 

 of Chili must attain by different degrees of 

 latitude, in order that their summits, more or 

 less grouped, pass not the line of perpetual 

 snows. The numeric results which I have just 

 marked, and which are founded on the laws. of 

 the distribution of heat, have still the same im- 

 portance as they had at the period already dis- 

 tant of my travels in America ; for there does 

 not exist in the immense extent of the Andes, 

 from 8° of south latitude to the strait of Magel- 

 lan, one Nevada of which the height above the 

 level of the Ocean has been determined, either by 



* On the southern declivity of the Himalaya, the snows 

 begin 3° nearer the equator, at 1970 toises. 



