155 



height, the mean temperature of the globe is 

 not below 1(>*8°, which was what the water of 

 the subterranean river indicated. We can even 

 prove, that this temperature of the globe is not 

 above 19°; since the air of the cavern, in the 

 month of September, was found at 18* 7°. As 

 the mean temperature of the atmosphere, in the 

 hottest month 7 does not exceed 19*5° it is pro- 

 bable, that a thermometer placed in the open 

 air in the grotto, would not rise higher than 

 19° in any season of the year. These results, 

 as well as many others, which we have record- 

 ed in this journey, seem of little importance, on 

 viewing them singly ; but, if we compare them 

 with the observations recently made by Messrs. 

 von Buch and Wahlenberg, under the polar 

 circle, they throw light on the economy of na- 

 ture in general, and the equilibrium of tempe- 

 rature, toward which the air and earth are con- 

 tinually tending. It is no longer doubtful, 

 that in Lapland the stony crust of the globe is 

 three or four degrees above the mean temperature 

 of the atmosphere. Does the cold, which per- 

 petually reigns in the abysses of the Equinoc 



* The mean temperature of the month of September at 

 Caripe is 18' 5° ; and on the coast of Cumana, where we had 

 opportunities of collecting a great number of observations, 

 the mean heat of the warmest months differs only 1*8° from 

 that of the coldest. 



