MEXICO. 



103 



During our month's residence, the weather was ex- 

 tremely unsettled ; and twice during a few rainy days, 

 when the temperature was remarkably chill, we saw the 

 snow-line descend several thousand feet upon the great 

 volcanoes. 



For the remainder of the short period alluded to, the 

 weather was warm, and occasionally hot ; with partial 

 thunder showers, during the passage of which the streets 

 of the city were deluged by water to that degree that 

 the crossings would have been impracticable for fine gen- 

 tlemen and ladies with shoes and stockings, were it not 

 for the cargadores and Indians, upon whose backs we 

 were taught to mount without scruple, in order to save 

 ourselves a wetting. 



As to the rest, we could not be insensible to the pecu- 

 liar rarity and dryness in the atmosphere, for which the 

 table land is remarkable. The sensation of the heat on 

 the skin is far greater than the degree of warmth indi- 

 cated by the thermometer would appear to warrant, 

 owing to the astonishing degree of reflection of the sun's 

 rays, which is produced by the vast and naked spread of 

 the plains, the masses of mountains by which they are 

 surmounted, and the diminished pressure which the rari- 

 fied air exerts upon the moisture given forth by the body. 

 The most violent exercise never produces the slightest 

 sign of perspiration ; at the same time that you can 

 ascend no elevation, not even the steps of houses, with- 

 out being sensible of an unusual shortness of breath. 



But while I have dipped my pen in my inkstand to 

 allude to natural phenomena, I must not forget to men- 

 tion the earthquakes, from which the city is rarely ex- 

 empt at this season of the year. 



1 omitted to mention at the close of the preceding let- 

 ter, that when we arrived at our last halting place before 

 entering the city, we heard that the first earthquake of 

 the season had been felt at ten the preceding night ; and 

 that more than usual alarm had been excited, on account 

 of the duration, force, and the character of the shock. 

 This I am convinced I felt at San Mateo, where we slept 

 on the night in question \ though it was shrouded in the 



