476* APPENDIX. 



scriptions ; while, without this, he will deserve that 

 his knowledge be called in question. 



Of the tertiary strata, I have already fully stated what 

 I consider a true arrangement ; referring also to the 

 last chapter, in preference to the one which treats on 

 that subject. To that the reader may turn for what I 

 need not repeat; but let the substances be at least de- 

 scribed as they exist; since, to give such names, alone, 

 as "The plastic clay," or " the calcaire grossier" is to 

 do worse than nothing. Let their elevations also and 

 their relations to the inferior rocks be noted : as, through 

 their physical geography, carefully examined, we shall 

 distinguish them from those deposits with which they 

 have been confounded. As to mineral veins, it is at 

 least necessary that they should be carefully examined, 

 and described in all their accidents ; in the rocks which 

 they traverse, in their contents, and in the variations 

 of those : while further, under whatever circumstances 

 pure minerals may occur, it is the geologist's duty to 

 describe these, since it is to him that mineralogy must 

 always be indebted for this knowledge. 



Studying brevity as I have here done, it will still 

 remain for the discretion and knowledge of an observer 

 to add what he thinks may contribute to geological 

 science; as he is permitted whatever may enhance its 

 interest to the reader. But let him ever remember 

 that if by commencing his career in England or Saxony, 

 or by trusting to books and professors, he has deter- 

 mined that any given country is his pattern of nature 

 and point of reference, he has already bandaged his 

 eyes; for it is certain, that wherever he goes he will 

 see nothing but the succession or " formation" in vogue ; 

 " the muschelcalk" or "the greensand," the The of his 

 school or system. Let him study nature with his own 

 eyes, and infer by his own reason : else will hisObser- 



