I02 NEW YORK STATE MUSEUM 



along all remaining shore lines. Logan and his successors have regarded 

 the course of the St Lawrence river as the locus of a great fault,' and it is 

 entirely within reason to assume a displacement of the sedimentaries 

 against the Archean land along this course ; yet the assumption of this great 

 fault does not to us seem essential to the interpretation of the structure of 

 the region nor a necessary accompaniment to the plication of the great 

 geosyncline. 



^See the delineation of its course on the general geological map of Canada, 1882. 



