294 Mr. Ben NET on the Island of Teiierife. 



is here no appearance of columnar formation, the lava being earthy 

 and porphyritic ; this continuity of wall, at present so easy to be 

 traced, may be considered as forming the sides of one immense 

 crater, from which perhaps originally the lavas of the island flowed, 

 which might have thrown up the cone of the peak, and covered 

 these wide-spreading plains or clanuras with the deep beds of ashes 

 and pumice. On this plain or desart, for we had long left all shew 

 of vegetation, except a few stunted plants of Spanish broom,a sensible 

 change was felt in the atmosphere ; the wind was keen and sharp, 

 and the climate like that of England in the months of autumn. All 

 here was sad, silent, and solitary. We saw at a distance the fertile 

 plains on the coast, lying as it were under our feet, and affording a 

 cheerful contrast to the scenes of desolation with which we were 

 surrounded ; we were already 7 or 8000 feet above the level of the 

 sea, and had reached the bottom of the second region of the peak. 

 Immense masses of lava, some cf them many hundred tons in 

 weight, lie scattered on these pumice plains. Some are broken by 

 their fall, and all wear the appearance of having been projected by 

 volcanic force. Their composition is uniformly porphyritic, with 

 large masses cf feldspar ; the v/holc compact and heavy, and bear- 

 ing no resemblance to the earthy lava we had seen in such abundance 

 prior to our entering these pumice plains. Many of these masses 

 are completely vltrihed, while others only shev/ marks of incipient 

 vitrification ; but from their site and fracture, from the insulated state 

 in which they lie, from there being no appearance of lava in a stream, 

 from the pumice bed being very deep, (and in one place I saw it ex- 

 posed to a depth of betvv'een 20 and SO feet) from all these facts 

 taken together, there can be little doubt that these masses were thrown 

 out of the mountain v^^hen that lava flowed, which is of similar sub- 

 stance, and which is called by the Spaniards El Mai Pais, 



