HORNBLENDE SCHIST. 309 



hornblende are imbedded in the crystalline ag- 



gregate. 



SECOND DIVISION. 

 Compound : of two ingredients, 



A. A laminar alternation of hornblende and felspar, 



a. Continuous platy and schistose, easily split- 



ting. 



b. Continuous platy, but scarcely or not at all 



fissile. 



* 



c. Granularly laminar, and imperfectly schis- 



tose. 



B. The hornblende scaly or fibrous, and the felspar 

 arenaceous : not occupying distinct laminae. 



C. A granular uniform mixture of the same ingre- 

 dients. 



a. Scaly, splitting into rough schists or imper- 



fectly fissile. 



b. Uniformly arenaceous and mixed ; fissile. 



c. Mottled, from the particles of hornblende 



being condensed in spots and patches. 



d. Dull, both substances minutely intermixed 



and compacted. 



e. A very compact distinct intermixture of the 



two ingredients : not schistose, and un- 

 distinguishable from the greenstone of 

 the overlying rocks. 



. Manyaspects result from the vary ing sizes of the 



