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XXIX. Geological Remarks on the Cartlane Craig, 

 By Dr Macknight. 

 (Read I2th February 18 14 J 



It is remarkable, that amongst the phenomena of 

 the mineral kingdom, on which the two geologi- 

 cal theories now in discussion, have been founded, 

 there should be so many that do not admit of an 

 unequivocal or exclusive application to either side 

 of the question at issue. A great number of these 

 appearances may be explained on the principles 

 of both systems, so as to render it a matter of 

 doubt with some enquirers, to which of them w^e 

 ought to give the preference ; nor is there per- 

 haps a single fact yet observed, which is acknow- 

 ledged on all sides as possessing distinctly the cha- 

 racter of what may be called an experimentum 

 crucis, to decide the faith of mineralogists. 



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