mm- 



\_To face page 72.] 



iordial 

 t-Pri- 



iGrifc, 



Shales 



es(Up- I g 



idstone 

 ^ula- y 



^■■^^S Fre-Frimordial Trap. 



Granitic and Quartzo- 

 felspathic veins. 



Pre-Cambrian, or 

 Laurentian Eooka. 



Faults. 



Scale 1 inch to the mile. 



