130 SIENITIC GREENSTONE OF FASSNEY. 



lour, and the mica diminishing in quantity. The 

 geognostic characters enable us to distinguish it 

 sufficiently from Sienite. 



The name Sienitic Greenstone, as used by Pro- 

 fessor Jameson, for this rock, appears to me hap- 

 pily chosen, and quite unobjectionable. 



This rock has been strangely confounded with 

 Granite, by Dr Hutton and Mr Play fair ; and I 

 shall conclude with a quotation from the " Illus- 

 " trations" of that system by the latter, with a 

 view of pointing out to those who are inclined to 

 admire the Huttonian Theory, one of the nume- 

 rous and glaring errors upon which it has been 

 founded. 



4 6 Another instance," says Mr Playfair, " of 

 " real Granite, disposed in regular beds, but 

 " without any character of Gneiss, is one which I 

 " saw in Berwickshire, in Lammermuir, near the 

 " village of Priestlaw. The little river of Fass- 

 " net cuts these beds across, and renders it easy 

 " to observe their structure," &c. 



We may ask, Where was Granite ever seen 

 without Quartz, and united with Hornblende, and 

 in such a situation ? 



