312 HORNBLENDE SCHIST. 



great ; but, in this case, the hornblende is black, 

 and scaly or granular ; the actinolite green and 

 fibrous. 



K. Hornblende and indurated talc. 



i 



This variety appears to pass into serpentine, 

 and is enumerated under that head. 



THIRD DIVISION. 



Compound : of three or more ingredients. 



A. Hornblende, mica, and felspar. 



B. Hornblende, felspar, and quartz. 



C. Hornblende, actinolite, and mica. 



D. Hornblende, chlorite, and felspar. 



E f Different quaternary mixtures of these ingrer 

 dients, which do not require to be particularly spe- 

 cified. 



These varieties are placed here for facility of 

 reference ; but some of them appertain to gneiss, 

 under which head they are also enumerated, 

 while others will be found under other titles. 



The varieties of aspect in all the rocks of this 

 division are endless, and arise from the varying 

 colours, magnitude, proportion, and intermix- 

 ture of the several ingredients. 



