78 



CLASSIFICATION OF ROCKS. 



Artificial System. 



PRIMARY CLASS, 



STRATIFIED. 



Gneiss. 



t Micaceous schist. 

 Chlorite schist. 

 Talcose schist, partial. 

 Hornblende schist. 

 Actinolite schist, partial. 



* Quartz rock 



* Red sandstone 



t Argillaceous schist, fine clay slate and 



gray-wacke. 



Diallage rock. Apparently ambiguous. 

 Serpentine. Ambiguous. 



J Limestone. 



Compact felspar. Partial. 

 Jasper, modified from * 

 Siliceous schist, modified fromt 

 Chert, modified from J when 

 argillaceous 



where gra- 



/are present: 

 partial. 



UNSTRATIFIED. 



Granite. From the ordinary appearance, 



to that of greenstone arid basalt. 

 C. Felspar porphyry. When ^ 

 decidedly limited to the 

 primary strata 

 Clinkstone and Claystone. In 



the same cases. 

 Serpentine. When sftlely connected with 

 primary strata, or granite. 

 Diallage rock. Not satisfactorily proved. 



often doubt- 

 ful 



Natural 

 System. 



Class 1. 



Protolith ? 



&c. 



Class 2. 



SECONDARY CLASS. 



STRATIFIED. 



* Sandstone. Conglomerate and fine. Old red. 

 series below ) Of various colours and qualities. 



Coal 



Limestone. Mountain limestone of English. 

 Transition of some. 



Class 3. 



Coal peri 09 



* Sandstone, 

 t Shale 



* Clay 

 Limestone 

 Coal 



Various. 



}DO. 



Class 4. 



