159 



periment of Mr. Lamanon, the water had not 

 reached the maximum of it's temperature*. 



The dawn appeared when we left the cavern 

 of ice. We observed, during the twilight, a 

 phenomenon which is not unusual on high 

 mountains, but which the position of the vol- 

 cano, that we were scaling, rendered very strik- 

 ing. A layer of white and fleecy clouds con- 

 cealed from us the sight of the ocean, and the 

 lower region of the island. This layer did not 

 appear above 800 toises high ; the clouds were 

 so uniformly spread, and kept so perfect a level, 

 that they wore the appearance of a vast plain 

 covered with snow. The colossal pyramid of 

 the peak, the volcanic summits of Lanzerota, of 

 Fortaventura, and the isle of Palma, were like 

 rocks amidst this vast sea of vapors, and their 

 black tints were in fine contrast with the white- 

 ness of the clouds. 



While we were climbing over the broken lavas 

 of the Malpays, we perceived a very curious op- 

 tical phenomenon, which lasted eight minutes. 

 We thought we saw on the east side small rockets 

 thrown into the air. Luminous points, about 

 seven or eight degrees above the horizon, ap- 

 peared first to move in a vertical direction ; but 

 their motion was gradually changed into a real 

 horizontal oscillation. Our fellow travellers, our 



* A. calculation, made according to the tables of Mr. Dai- 

 ion, gives 89*4° for La Cueva, and 89*5° for Guadaloupe. 



