lb PROCEEDINGS OF THE CANADIAN INSTITUTE. 



ever, these pioneers were overjoyed to learn on the authority of an expert that the 

 mineral was not apatite, but corundum. 



Eleven years ago Professor Coleman, now of the School of Practical Science 

 at Toronto, picked up some boulders of nepheline-syenite in the vicinity of 

 Cobourg, on the shore of Lake Ontario, which held crystals of corundum. A 

 fortnight ago I showed Dr. Coleman several specimens of nepheline, rich in cor- 

 undum, which I had taken from a large deposit recently discovered in the town- 

 ship of Dungannon, and he at once pronounced them to be identical with his own. 

 " I feel sure now," he said, " that I know where my float-boulders came fromi" 



Twelve years ago, in 1886, Nesbitt T. Armstrong, a farmer and mill-owner in 

 Carlow, discovered corundum on lot 14, in the I4thi concession of that township, 

 but he did not know its name, and did not suspect that it possessed any value. A 

 sample was shown to a student of Toronto University, who thought it might be 

 emery: and inquiry stopped there. But in 1893 Mr. W. F. Ferrier, lithologist of 

 the Geological Survey, acquired by purchase a number of specimens collected by 

 Mr. John Stewart, formerly of Ottawa, among which was a package labelled 

 " Pyroxene crystals, south part of Carlow." On examining these specimens some 

 time afterwards, presumably in 1896. Mr. Ferrier recognized them as corundum, 

 and immediately took steps to ascertain the precise locality from which they came. 

 In October, 1896. he was sent upon this mission by Dr. Dawson, the head of the 

 Geological Survey, and, guided by Mr. Armstrong, he found the corundum in 

 place upon the ilot on which Armstrong's discovery had been made ten years 

 before. Then for the first time the fact was established, on the best authority, 

 that this mineral had been found to exist in Canada in commercial quantity, and 

 thrt it was valuable as an abrasive material on account of its great hardness. But 

 as it was too 'late in the season for field-work, Mr. Ferrier did not extend his 

 explorations beyond that one locality. 



The first geological reconnaissance of the district in which corundum has been 

 found was made by the late Alexander Murray, of the Geological Survey, in 1853; 

 but his notes of it are very meagre. Mr. Murray made two traverses of the coun- 

 try lying between Georgian Bay and Ottawa river — the first from west to east, 

 by way of the Muskoka and Petewawa rivers, and the second by way of the 

 Bonnechere and Madawaska, to the headwaters of the Trent. The source of the 

 Bonnechere is within a rpile of Kaminiskeg lake, on the Madawaska, near to 

 where Barry's Bay station, on the Ottawa and Parry Sound Railway, now stands. 

 Mr. Murray descended the Madawaska to the mouth of its principal tributary, the 

 York branch, or York river; known, also, at that time, by its significant Indian 

 name of Shawashkong, or Mishawashkong, the river of the marshes. The course 

 of this stream, which Mr. Murray ascended, lies for more than forty miles within 

 the corundum belt; and along its banks are numerous exposures of syenite, with 

 occurrences of nepheline-syenite. But no reference is made in the report to the 

 rock formations; and the record of levels for the first ten miles is of very doubtful 

 accuracy.'!) 



Forty years elapsed before another attempt was made to work out the geology 

 of this interesting area, and the task was then entrusted to the very capable hands 

 of Dr. Frank D. Adams. The area under examination is comprised in sheet 118 

 of the Ontario series of geological maps, and the four corners of it lie in the town- 

 ships of Digby, Finlayson, Hagarty and Grimsthorpe respectively, embracing an 

 area of about 3,500 square miles In his first report, made for the season of 1893, 

 Dr. Adams sketched briefly the geological features of the district, the northern 

 portion of which he found to be occupied exclusively with the ancient crystalline 

 rocks of the Laurentian system, and the southern and eastern portions with the 



(i) The rock formations along the York River, however, are carefully noted on the maps which accom- 

 panied the report, as are also the waterfalls and rapids of the river from its mouth to its source. 



