LAURENTIAN TRAP-ROCKS. 285 



with a beautiful golden-colored mica. A rock which ap- 

 pears identical with aphanite, although not at all igneous, 

 I also found, yet, with all this apparent variety, the transi- 

 tions are too gradual to permit the differences to leave 

 any effect on the landscape." 



For some notes on the geology of Hamilton Inlet we 

 are indebted to Mr. Davies : " In some places mica slate 

 was found — it is said that the Mealy Mountains are com- 

 posed of this rock. I had no opportunity of verifying 

 this fact, as I did not visit them. Granite was only seen 

 in one place, viz., on Lake Keith, an expansion of the 

 Grand River, about one hundred and thirty miles from 

 its mouth. Specimens of chlorite schist were also pro- 

 cured on this lake, as was also a specimen of sandstone, 

 with disseminated grains of iron pyrites. At some dis- 

 tance below the lake, primary marble, of a beautiful 

 whiteness, was seen cropping out at the edge of the 

 water ; it was found in contact with a quartz rock pass- 

 ing into mica slate, having crystals of common garnet 

 imbedded in it ; this was the only place where limestone 

 of any sort was seen. 



" The shores of the bay where they are not of rock are 

 generally composed of rolled fragments of syenite, mica- 

 slate, quartz, hornblende, sometimes in large masses, 

 feldspar, etc. Magnetic iron in the form of sand was 

 also met with in some of the small coves." 



Laurentian Trap-rocks. — At Henley Harbor is a 

 system of trap-rocks which have been upheaved in a 

 N. N. E. and S. S. W. direction, in a course much more 

 northerly than the direction which the Straits of Belle 

 Isle assume. These rocks consist of three masses of co- 

 lumnar basalt, capping the syenitic gneiss. It is a hard. 



