14 LETTER IV, 



M. Buflfbn imagines that some of the mountains of 

 Asia, particularly those of Taurus, imatis, Caucasus* 

 and the mountains of Japan, as well as the moun- 

 tains of the Moon, in Africa, from whence the 

 principal branch of the Nile arises, are higher than 

 any part of the Alps. This point however does not 

 appear to be well ascertained ; but we have it from 

 good authority that the Andes, in South America, far 

 exceeded in elevation the highest mountains of the 

 old world. The perpendicular height of Chimbo- 

 razo, the most elevated summit of the Andes, is as- 

 serted by Juan de Ulloa to be nearly three miles, and 

 a half. The same traveller also informs us that the 

 line of congelation, where perpetual frost begins, is 

 about half a mile perpendicular below tne summit, 

 It is in general observed that the mountains of the 

 torrid zone are higher than those of the temperate,, 

 and these higher than those of the frigid zones. The 

 cause of this, like that of many other circumstances 

 of the physical and moral world, is unknown ; but as- 

 we can easily perceive order and design in all the 

 works of nature as far as our researches can reach; 

 we are fully authorized to suppose that the same con- 

 sisten^cy of plan exists in those which lie beyond the 

 sphere of our comprehension. If,, therefore, we 

 should, on this principle, hazard a conjecture, it is not 

 improbable that infinite wisdom has formed the high- 

 est mountains nearest to the equator in order to attract 

 and form into clouds that immense mass of vapours 

 exhaled by the ocean in those regions where the SUIL 

 is vertical, and, by, this process, of nature, to purity 

 the atmosphere and render it less insalubrious than it 

 would be if the surface of these countries were more 

 uniformly level. 



It would, sir, confine your attention too long to 

 this subjectj.where I to describe t', er so concisely, or 

 even enumerate, all the mountains with which the 

 face of this globe is diversified. There are, however, 

 a few which are too remarkable to be passed over in 

 silence. These are the volcanoes or burning moun- 

 tains. These contain within their bowels sulphur and 



