624 PROCEEDINGS OF BOSTON MEETING. 



with a number of typical kettle holes nearly as deep. The composition was largely 

 coarse. Another mile north, on the land of Mr White, is another gravel deposit 

 somewhat similar and plainly of glacial origin. Near Mr Sache's house the alti- 

 tude in the road is about 90 feet above the Nelson beach. The surface in that 

 vicinity is hilly and rough and the ground is a heavy bowlder clay. The drainage 

 is westward into Duchesnay creek, which empties into lake Nipissing. 



Thus upon both positive and negative • evidences of submergence, the Nelson 

 beach was found to be the highest postglacial shoreline on the hills north of 

 North bay. 



The south Shore of the Strait. 



On the south side of the Nipissing pass the hills are much farther away, the near- 

 est accessible point at an altitude corresponding with the Nelson beach being at 

 Trout creek, about 28 miles south-southeast from North bay. The highest post- 

 glacial shoreline was located at Sundridge and South river, and lines a little lower 

 were found at Trout creek. The first visit to these localities was made before the 

 first one to North bay, and closed a two weeks' trip along the line of the Northern 

 and Pacific Junction railway. The detailed account of those localities belongs to 

 the record of that trip and will therefore be omitted here. 



Well formed beach ridges of fine gravel were found at Sundridge facing south 

 over the wide basin of Stony lake, which was an arm of the expanded waters at 

 the time of the great submergence. The highest is at an altitude of about 1,205 

 feet above sealevel. At South river a cut terrace 50 to 60 feet above the level of an 

 immense deposit of finely bedded clay and white silt overlain by sand was found 

 at an altitude of about 1,220 feet. These two localities are only about five miles 

 apart and were connected with each other and also with the ancient strait to the 

 north. At Trout creek, 11 miles farther north, the level of the highest line at 

 South river was not reached, but evidences of submergence were seen up to about 

 1,150 feet above sealevel. The failure to reach the highest line at this place was 

 accidental and affords no just ground for presumption against the inference that a 

 shoreline probably exists there at a slightly higher level than that at South river. 

 The altitudes of these localities are based on the heights of the stations above lake 

 Ontario, as given on the profile of the railroad in the engineer's office at Toronto. 



The finding of the highest beach considerably higher on the south side of the 

 Nipissing pass than on the north is rather exceptional among beaches, which almost 

 universally rise northward ; but it is not surprising when due account is taken of 

 the very marked eastward component of differential elevation, which is well estab- 

 lished by the observations of Dr Spencer farther south. 



The ancient strait, as defined by the two highest shorelines described, was about 

 32 miles wide at the place of observation ; but the hills draw nearer to each other 

 toward the east, and the narrowest part of the strait was probably not less than 25 

 miles wide. Its depth over the low i^ass between lake Nipissing and Trout lake 

 must have been more than 500 feet. 



The Ohnaping Delta. 



One other locality may be appropriately mentioned in this connection. It is 

 about eight miles east of Cartier, which is on the main line of the Canadian Pacific 

 railway, 125 miles west-northwest from North bay. On the way east I stopped off 



