GENERAL J' 1(0 PORT TONS. 
95 
at three hundred and seventy toises high, the cone detaches 
itself from the plain of Atrio dei Cavalli. The peak of 
Teneriffe presents two of these elevated plains, the upper- 
most of which, at the foot of the Piton, is as high as Etna, 
and of very little extent ; while the lowermost, covered with 
tufts of retains, reaches as far as the Estancia de los 1 n- 
gleses. This rises above the level of the sea almost as high 
as the city of Quito, and the summit of Mount Lebanon. 
The greater the quantity of matter that has issued from 
the crater of a mountain, the more elevated is its cone ot 
ashes in proportion to the perpendicular height ol the vol- 
cano itself. Nothing is more striking, under this point ot 
view, than the difference of structure between Vesuvius, the 
peak of Teneriffe, and Pichincha. I have chosen this last 
volcano in preference, because its summit* enters scarcely 
within the limit of the perpetual snows. The cone of Coto- 
paxi, the form of which is the most elegant and most regular 
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 
3 
Peak of Teneriffe 
190-1 
81 
A 
Pichincha 
2190 
210 
A 
This table seems to indicate, what we shall have an op- 
portunity 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 their summits. Thus the crater 
at the extremity of the Piton, which is called the Caldera, 
* I have measured the summit of Pichincha, that is the small moun- 
tain covered with ashes above the hlano del Vulcan, to the north of Altc 
de Chuquira. This mountain has not, however, the regular form of a cone. 
As to Vesuvius, I have indicated the mean height of the Sugar-loaf, oa 
account of the great difference between the two edges of the crater. 
