GEOLOGY OF THE COUNTRY. 89 



There can be no doubt, but that these rocks belong to a newer class 

 than any which we have yet seen — the extent of the formation I had no 

 opportunity of ascertaining — it probably occupies, at least, all the lower 

 portions of the elevated plain on which we were encamped, the rising 

 grounds, as we have seen, being formed of the nearly vertical strata of 

 the underlying rocks. Nothing like organic remains could be traced, 

 though I examined with care the different masses which had been thrown 

 out by the borers. Through the above rocks a vein of quartz was seen 

 to pass -it gradually narrowed frum below upwards till it terminated at 

 the surface, where it was about a foot and a half in thickness, the lowest 

 portion of it seen, being about two yards broad. The quartz was of a 

 pure white color and crystallize texture. It was not stratified, but pre- 

 sented the appearance of a number of rounded masses closely cemented 

 together — the Huttonian might say, that it derived this form from having 

 been ejected from below, the Wernerian, perhaps, that it had been a pre- 

 viously existing rent in the strata which had been filled up from above 

 by rounded masses of quartz derived from the neighbouring hills, and 

 which are seen strewed over the whole surface of the plain. The latter 

 is certainly the more probable theory, as the masses of quartz were ce- 

 mented together by a calcareous cement of obviously a posterior forma- 

 tion to the quartz. 



In which precise class of rocks, the above ought to be included, I 

 have had no means of ascertaining ; in their nature and structure, how- 

 ever, they resemble the rocks of the new red sandstone formation of Ja- 

 meson, and I should feel induced to consider them as belonging to this 

 class. No rocks of a similar nature have occurred to me during my 

 march, nor do I think that, in the country passed after leaving this, any 

 do exist, for in almost every situation the vertical strata appear at the sur- 

 face, it is more than probable, however, that the rocks examined formed 



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