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at the level of the sea, it is 20° or 21°. The 

 cold does not increase on our mountains so 

 rapidly as the heat diminishes. We shall find 

 as we advance toward the Cordilleras, that 

 under the torrid zone the climate is more uni- 

 form in the plains, than on the mountains. At 

 Cumana and La Guayra (for we must not cite 

 places where the north winds disturb for some 

 months the equilibrium of the atmosphere) the 

 thermometer keeps during the whole year be- 

 tween 21° and 35°. At Santa Fe and Quito 

 we find it vary from 3° to 22°, if we compare, 

 I do not say the days, but the coldest and 

 warmest hours of the year. In the low regions, 

 at Cumana for instance, the nights differ from 

 the days only three or four degrees. At Quito, 

 I found this difference, taking carefully, every 

 day and night, the mean of four or five obser- 

 vations, amounting to seven degrees. At Ca- 

 raccas, placed on a spot nearly three times 

 less in height, and on a table-land of little ex- 

 tent, the days in the months of November and 

 December are still from 5° to 5*5° hotter than 

 the nights. These phenomena of nocturnal re- 

 frigeration may astonish at the first view : they 

 are modified by the table-lands and the moun- 

 tains being heated during the day, by the action 

 of the descending currents, and above all by 

 the nocturnal radiation of caloric in the pure 

 and dry air of the Cordilleras. The following 



