THE LAURENTIAN ROCKS. 28 1 



mated by Bayfield to be twelve hundred feet high. Be- 

 tween Belles Amours and Anse-au-Sablon, on the north- 

 ern side of the Strait of Belle Isle, occur the lower 

 Silurian or Taconic rocks, which have been already fully 

 described in the " Geology of Canada," published by the 

 Canadian Geological Survey. In coasting within a mile 

 or two of this interesting region we see the red sand- 

 stones running out as a low point of land resting on the 

 lofty, precipitous Laurentian rocks. Between Bradore 

 Bay and Anse-au-Loup these sandstones and grits rise 

 up to a height of five to six hundred feet, forming the 

 coast-line ; and looking up through the bays and harbors 

 we can see the low conical hills of Laurentian gneiss in 

 the interior. At the eastern termination of this forma- 

 tion the Laurentian rocks rise into high, rugged, and 

 broken syenitic hummocks, in marked contrast with the 

 regular terraces and smooth slopes of the fossiliferous 

 sandstones and limestones. Approaching Henley Har- 

 bor, there is a visible change in the scenic features of 

 the coast ; the hills grow more regular in outline, and 

 slope gradually to the water, giving us the peculiar 

 physiognomy of the Laurentian gneiss. 



Upon entering Henley Harbor the dark gneiss is seen 

 resting upon syenite, and at the point of contact inter- 

 penetrated by irregular intrusive masses of the latter 

 rock. On Henley Island, where these rocks crop out 

 under the trap capping this island, there appears a true 

 syenitic gneiss, very hard, distinctly stratified, and of the 

 usual flesh color of the syenite. 



At this point I broke off" some pieces of nearly un- 

 stratified syenite which showed very distinctly the sedi- 

 mentary origin of the rock, for the cavities were often 



