New York State Museum Bulletin 



Entered as second-class matter November 27, 191S, at the post office at Albany, N. Y.. under 



the act of August 24, 191 2 



Published monthly by the University of the State of New York 



No. 185 ALBANY, N. Y. May i, 1916 



The University of the State of New York 



New York State Museum 



John M. Clarke, Director 



THE PRECAMBRIAN ROCKS OF THE CANTON 

 QUADRANGLE ^1k««^^^«^ 



BY 



JAMES C. MARTIN 



AW8 5 19t6 



% 



INTRODUCTION ^>l^}^ 

 The Canton quadrangle (see key map, figure i), lies~somewhat 

 to the northwest of the center of St Lawrence county, New York. 

 Bounded by parallels 44° 30' and 44° 45^ and meridians 75° and 

 75° 15', it embraces an area of approximately 212 square miles. 

 In a geological sense the district lies on the northwest outskirts 

 of the Adirondack moimtains, while physiographically it flanks 

 the line of foothills which mark the approach to the rugged interior. 

 So far as bedrock is concerned, the larger part of the quadrangle, 

 that is, the southern two-thirds, as truly belongs to the Adiron- 

 dacks as any of the more highly elevated districts adjoining it. 



During the past century or more, the crystaUine rocks of the 

 mountains have attracted the careful attention of many observers. 

 For a full bibliography and summary of Adirondack literature up 

 to and including 1908, the reader is referred to the bulletin by Van 

 Hise and Leith (1909, pages 597-621)-^, and the publications of 

 the State Geological Survey, to which the writer is indebted for the 

 following brief notes covering the activities of this period. 



Some twenty-six investigators, working often in widely separated 

 places, have contributed in varying amount to our knowledge of the 

 vast assemblage of metamorphic rocks which make up this moun- 

 tain system. Among the workers of the earlier period were Jessup, 

 Eaton, Emmons, Conrad, Vanuxem and Mather. Emmons pub- 

 lished (1842) the first comprehensive summary of contemporary 



^See list of references at end of bulletin. 



