300 Mr, Ben NET on the Island ofTeneriffe. 



which we ascended ; from this side flowed the basaltic lavas of 

 1704, and of the last eruption in 1797; this latter stream of 

 lava flowed in a remarkably slow current, for notwithstanding the 

 sharp descent of the mountain, and the length of the lava not 

 exceeding three miles, several days elapsed before it reached the 

 spot where it stopped ; how little fluid this lava must have been is 

 evident, when it is remembered that the lava of Vesuvius in 1794, 

 which destroyed Torre del Greco, reached the sea from the bottom 

 of the cone, a distance of eight miles, in little more than six 

 hours. M. Escolar further told me that there is on this south- 

 western side of the Peak an ancient lava, at present not at all 

 decomposed, of several miles in length, and in a perfect state of 

 vitritication ; the whole of this stream has the appearance of 

 obsidian. All these lavas appear to have flowed from the bottom 

 of the cone, and to have run from its base in the same manner as 

 that of Vesuvius in 1794, the crater of which vomited out ash and 

 pumice, and large pieces of rock, while the current of lava issued 

 from its side. It is not however improbable that the cone itself is of 

 anterior formation to this vitrified lava, as the summit of the Peak 

 is similar to the lava of the Mai Pais^ and that being porphyritic is 

 considered as of more ancient date than the one above mentioned, 

 which is basaltic. 



If one might hazard a conjecture upon a subject where the data 

 are so few, I should be inclined to suspect that the Peak itself, as well 

 as the whole of the country around it which forms its base, were 

 produced by that immense crater called Las Canales^ the shape and 

 magnitude of which I have before taken notice of when traversing 

 the pumice plains ; it is also well worthy of remark that there is 

 no volcano in action at all to be compared in size of crater to those 

 that are extinct. The ancient crater of Vesuvius is considerably 



