— 104 — 



dike is steep-wall-like in fact — rising to a height ot 



about 40 feet at some places. Where the base is 



exposed on the northern side, the stones composing 



this dike are seen to rest on the conglomerate aqueous 



rocks of which the cliffs of the southern end of the 



Island are composed. — And what is still more curious 



is that on descending to the bottom of what one 



would suppose to have been the centre of the crater, 



the exposed rocks were found to be the same aqueous 



conglomerate as the cliffs. 



The " Deux Mamelles " present a particular 



appearence. — They are cone shaped* — The points of 

 the cones almost, if not quite, overhang their basis 



on the eastern side. They are composed of tne same 



kind of aqueous material as the surrounding rock ; 



but the material has been much hardened by heat, 



and some portions of it have a scorched appearence, 



resembling that of a hard burned brick. The rock 



of which these cones are composed, is shattered into 



large angular blocks. Large pieces of coral abound 



in the aq^ueous conglomerate. In a vein of it, which 



is exposed in the cliffs near the Palissade Bay, some 



small angular pieces of basaltic rocks were discovered. 



At a place on the south side of the cliffs and near the 



sea, where the rock, being soft, has been much worn 



by the weather, veins of a substance resembling talc 



were found. This mineral, talc, is composed of silica 



and magnesia. It feels soft, as if greasy, to the touch. 



It is found in crumbling, laminated and foliated 



masses of a greenish, or yellow white j or soap-stone* 



It is used for pipe heads, crayons for writing upon 



cloth j also for crucibles, as a grease absorbent and in 



tnaking porcelain. It enters into the composition of 



many rocks, particularly schists, serpentines, etc. 



The veins]|are each about half an inch in thickness. 



