and the other Channel Islands. 5 



regularity of their position gives them in some places, where their 

 edges are exposed, a form so apparently columnar, that they might 

 at a distance be mistaken for basalt : and when a succession of these 

 ribs appears cropping through the grass, the appearance as of the 

 skeleton of a mountain is exhibited. The cliffs give no opportunity 

 of observing on what bottom this sandstone rests, as the tide flows 

 high round them. I have remarked that it becomes finer and 

 whiter as it approaches the south-west, that is to say, the strata 

 which in their original horizontal position were undermost, are the 

 whitest and finest. They, here also, approach nearer in their nature 

 to a sandstone flag ; acquiring a schistose fracture, though incapable 

 of being raised in large masses. The stone is however easily quar- 

 ried, and breaks naturally into masses having their sides slightly 

 inclined, or absolutely rectangular. It is therefore well calculated for 

 architectural purposes ; and abundance might be procured at a 

 small expense, very nearly adapted for squared building without 

 the assistance of the chisel. The few inclosures which are used in 

 the island are built of this stone without mortar. 



The principal varieties of the stone that I have been describing 

 are the following. 



1. White — very coarse — the quartz cemented by a clay the pro- 

 duce of the felspar. 



2. The sam.e — red — and with distinct grains besides, of felspar 

 imbedded in it. 



3. Dark red — and containing mica. 



4. The felspar so distinct as to reapproach to a fine-grained 

 granite. 



5. A variety consisting of very minute grains, and to the mag- 

 nifying glass exactly resembling a granite. 



