17 

 History of Investigation. 



The presence of nepheline in the vicinity of Port Coldwell 

 was known very early in the geological investigation of 

 Canada, and some details respecting its mode of occurrence 

 are included in the Report of Progress of the Geological 

 Survey of Canada for 1846-47 (1), as also in the Geology of 

 Canada 1863 (2). Attention was directed to these early 

 descriptions through the discovery in 1898 by Dr. A. P. 

 Coleman of the University of Toronto of a dyke rich in 

 analcite, near Heron Bay, for which rock he proposed the 

 name "heronite". Subsequently it was shown that 

 "heronite ' was really a decomposed tinguaite (3, 4, 5, 6). 



In 1900 Dr. Frank D. Adams of McGill University, 

 furnished under the title "On the Probable Occurrence of a 

 Large Area of Nepheline-bearing Rocks on the Northeast 

 Coast of Lake Superior" (7), a detailed petrographical 

 description of four thin sections prepared from two rock 

 specimens collected from the vicinity of Peninsula harbour 

 by Peter McKellar in 1870 and Dr. Selwyn in 1882. Dur- 

 ing the summer of 1900, Dr. Coleman again visited Heron 

 bay, but although successful in discovering certain dykes 

 rich in nepheline, he failed to locate any large area of rocks 

 containing this mineral. 



In 1901 another examination was made, during which 

 outcrops of nepheline and other closely related alkaline 

 syenites were revealed between Peninsula harbour and 

 Middleton station (8) on the Canadian Pacific railway. 



In 1902 Dr. T. L. Walker of the University of Toronto 

 spent a few days collecting museum specimens in this neigh- 

 bourhood. At his suggestion Mr. H. L. Kerr of the same 

 institution undertook a petrographical study of the speci- 

 mens then collected, as well as of those obtained by Dr. 

 Coleman, with a view of making a more detailed examina- 

 tion of the whole Port Coldwell area (9). 



During the fall of 1906 and again in 1907, Mr. Kerr spent 

 about ten weeks in all in the field gathering information 

 regarding the extent of country covered by the several 

 varieties of these syenites. Mr. Kerr's examinations and 

 descriptions have evidently been made with great care 

 and in such detail as to make possible a rather complete 

 and satisfactory statement of this interesting complex 

 of igneous rocks. 

 35069—2 



