300 



many degrees lower than that of the surrounding atmosphere. 

 These vessels are made very thin, and without any glazing. 

 They are accordingly so porous, that when filled with water, 

 it transudes in sufficient quantity to keep the surface con- 

 stantly wet; and when thus exposed to a current of air, the 

 evaporation from the outside maintains the contents of the 

 vessel in a state of refreshing coolness. 



" The whole of this soil appears to have been formed by 

 the decomposition of the trap. In some parts, this trans- 

 mutation is already nearly completed ; for, on penetrating to 

 any depth in the ground, we find nothing but a mass of 

 reddish earth, with here and there a small nucleus of stone, 

 enveloped in concentric crusts of matter, in an intermediate 

 state between that and soft earth. In other parts, however, 

 and those the more numerous, where the greater compactness 

 of the trap, or some other cause, has retarded the process 

 of disintegration, we meet with little or no earth, but with 

 angular masses of stone without any crust. 



'' Various French Naturalists who had occasion to examine 

 the structure of this island, have given it as their opinion, 

 that it is entirely of volcanic origin ; and if the description 

 of rocks known by the name of trap is proved to be a 

 product of fire, no spot upon the face of the globe has a 

 fairer claim to that origin : yet the attentive mineralogist will 

 stumble upon objects, the existence of which he will find 

 it difficult to reconcile with any theory which would attempt 

 to account for its formation, on the level, at least, where it 

 actually lies. 



" On the plain, for instance, that spreads out from the 

 base of the Tamarind Mountain, there is a mass of petrified 

 coral, about twelve feet high, and forty yards in circumference, 

 very httle sunk in the ground, and appearing as if it had 

 been dropped there by accident. It is disposed in three 

 distinct beds ; the lowest divested of every trace of organiza- 

 tion, and so indurated, that, on being struck, it gives a 

 metallic sound; the others still retaining their organic 

 structure, though several blocks of the common trap of the 

 island are seen imbedded in their substance. The ground 



