158 



sun do not penetrate beyond the mouthy the heats 

 of summer are not sufficient to empty the reser- 

 voir. The existence of a natural ice house de- 

 pends, consequently, rather on the quantity of 

 snow which enters it in winter, and the small in- 

 fluence of the warm winds that blow in summer, 

 than on the absolute elevation of the cavity, and 

 the mean temperature of the layer of air in which 

 it is situate. The air contained in the bowels of 

 a mountain is not easily displaced, as is proved 

 by Monte-Testaceo, at Rome, the temperature of 

 which is so different from that of the surrounding' 

 atmosphere. We shall see in the course of this 

 work, that on Chimborazo enormous heaps of 

 ice are found covered with sand, and, in the 

 same manner, as at the Peak, far below the in- 

 ferior limit of the perpetual snows. 



It was near the Cellar of Ice (Cueva del Hielo), 

 that, in the voyage of La Peyrouse, Messrs. La- 

 manon and Monges made their experiments on 

 the temperature of boiling water. These natu- 

 ralists found it 88*7°, the barometer being at 

 nineteen inches one line. In the kingdom of 

 New Grenada, at the chapel of Guadaloupe, near 

 Santa-Fe de Bogota, I have seen water boil at 

 89*9°, under a pressure of 19 inches 1*9 lines. 

 At Tambores, in the province of Popayan, Mr. 

 Caldas found the heat of boiling water 89*5°, the 

 barometer being at 18 inches 11*6 lines. These 

 results might lead us to suspect, that, in the ex- 



