210 



vius, t he Peak of TenerifFe, and Pichincha. 1 

 have chosen this last volcano in preference, be- 

 cause it's summit # enters scarcely within the 

 limit of the perpetual snows. The cone of Co- 

 topaxi, the form of which is the most elegant and 

 most regular hitherto known, is 540 toises in 

 height ; but it is impossible to decide, whether 

 the whole of this mass is covered with ashes. 



Names of the volcanoes. 



Total height 

 in toises. 



Height of the 

 cone covered 

 with ashes. 



Proportion of 

 the cone to the 

 total height. 



Vesuvius 



606 



200 



i 



3 



Peak of Teneriffe 



1904 



84 



i 



82 



Pichincha 



2490 



240 



i 



This table seems to indicate, what we shall 

 have an opportunity of proving more amply 

 hereafter, that the Peak of TenerifFe belongs to 

 that group of great volcanoes, which, like Etna 

 and Antisana, have had more copious eruptions 

 from their sides than from the summit. Thus 

 the crater at the extremity of the Pi ton, which 



* I have measured the summit of Pichincha, that is the 

 small mountain covered with ashes above the Llano del Vul- 

 can, to the north of Alto de Chuquira. This mount has not 

 however the tegular form of a cone. As to Vesuvius, I have 

 indicated the mean height of the Sugar-Loaf, on account of 

 the great difference between the two edges of the crater. 



