III. Remarks on the Transition Rocks of We r neb. 

 By Thomas Allan, Esq. F.R.S. Edin. 



^f^ 



IReadFeb. 17. 1812.] 



ALTHOUGH we have many writers on geological subjects, . 

 whose works are distinguished by ingenuity of doctrine, 

 and novelty of opinion, and, among them, some who have 

 made advances towards arrangement ; it was reserved to the 

 celebrated Werner, to introduce means, by which rocks might 

 be described with some degree of precision. Many ingenious 

 theories were invented, to account for their formation ; but - 

 little or no attention was paid, to the acquirement of an ac- 

 curate knowledge, either of their composition, or their relative 

 position in nature ; although these certainly appear to be the 

 bases, on which such speculative opinions ought to be found- 

 ed. 



But while we acknowledge these obligations to the Professor 

 of Freyberg, we cannot extend our unqualified approbation to 

 the systematic arrangement he has introduced. It was not to be 

 expected, that the labours of one individual, who, from peculiar 

 circumstances, was confined within certain limits *, were suffi- 

 cient 



* In Werner's Preface to his Theory of Veins, he states, that his limited for- 

 tune, and the nature of his present situation, prevented him from travelling into 

 more distant countries. Anderson's Translation, xxin. 



