DIVERSITY OP CLIMATE. 297 



varying more than eight or nine degrees. To this CHAP.xxiv 

 region, of which the mean annual temperaturfe is from -j — 

 08° to 69'8°, the natives give the name of Tierras tempiadaa 

 templadas. Unfortunately these tracts are frequently 

 covered with thick fogs, as they occupy the height to 

 which the clouds usually ascend above the level of the 

 sea. 



The plains which are elevated more than 7218 feet Tienas friiw. 

 above that level, and of which the mean temperature is 

 under 62*6°, are named Tierras frias. The whole 

 table-land of Mexico belongs to this description, which 

 the natives consider cold, although the ordinary warmth 

 is equal to that of Rome. There are plains of still 

 greater elevation, on which, although they have a mean 

 temperature of from 61 '8° to 55*4°, equal to that of 

 France and Lombardy, the vegetation is less vigorous, 

 and European plants do not thrive so well as in their 

 native soil. The winters there are not extremely severe, 

 but in summer the sun has not sufficient power over the 

 rarified air to bring fruits to perfect maturity. 



From the peculiar circumstances of New Spain, as influence ou 

 here sketched, the influence of geographical position ^ '^s^'*'^°'i- 

 upon the vegetation is much less than that of the height 

 of the ground above the sea. In the nineteenth and 

 twentieth degrees of latitude, sugar, cotton, cacao, and 

 indigo, are produced abundantly only at an elevation of 

 from 1968 to 2625 feet. Wheat thrives on the declivi- 

 ties of the mountains, along a zone which commences at 

 4593 feet and ends at 9843. The banana (^Musa para- 

 disiaca), on the fruit of which the inhabitants of the 

 tropics chiefly subsist, is seldom productive above 5085 

 feet ; oaks grow only between 2625 and 9843 feet ; and 

 pines never descend lower than 6069, nor rise above 

 13,124 feet. 



The internal provinces of tlie temperate zone enjoy a Difference of 

 climate essentially diff'erent from that of the same 

 parallels in the Old Continent. So remarkable an in- 

 equality prevails indeed between the temperature of the 

 seasons, that while the winters resemble those of Ger- 



