RED PRIMARY SANDSTONE. 183 



The reasons for ranking this sandstone in the pri- 

 mary class are now apparent, notwithstanding its re- 

 semblance to those of the secondary division; and, that 

 it is not even the latest of the primary strata, is evident 

 from the preceding history of its connexions. No ob- 

 jections need arise with respect to the application of 

 the term primary, to a rock composed of re-united frag- 

 ments, since the same character occurs in quartz rock, 

 and also in micaceous schist ; as there are also striking 

 analogies between the former series and the present, in 

 many important particulars. The obvious differences, in- 

 deed, frequently consist in little else than colour; fel- 

 spar being equally present in some kinds of quartz rock, 

 though of a paler hue than in this sandstone ; while both 

 have been generated from gneiss and granite, in these 

 cases, as, in others, from those, and from other strata of 

 a former series, as noticed in the chapter on the Revolu- 

 tions of the Earth. 



I may conclude these remarks by observing, that they 

 who do not choose to admit anew distinction, may consi- 

 der this as a modification of quartz rock. But the mag- 

 nitude and distinctness of the masses, with their marked 

 appearance and separation from the other forms of this 

 substance, seem to give it a claim to a place somewhat 

 more important than would arise from mere distinction 

 of colour; though I willingly leave it to the judgment 

 of others. If it is considered as unwarrantably intro- 

 duced into the antient catalogue, I cannot quote any con- 

 firmation of its existence elsewhere, from the writings 

 of foreign authors. But as M. Cordier has recently pro- 

 fessed to me his belief in a red sandstone, followed by a 

 schist, and anterior to that " old red sandstone" which 

 he takes care to distinguish from the red marl, it is 

 likely that the rock which I have now described does 

 actually exist on the continent of Europe. 



