298 K. I : I I I — GLACIAL PHENOMENA IN CANADA. 



fur the snow-fall on its own area ami a- a collecting basin for the ice from 

 tin- Dorthwesl ami thi and discharged it in vast sheets to the northeast- 



ward and the south ami southwest. The ice-sheet from this quarter would 

 he great enough to hold back the water of the hypothetical Lake A-gassiz, 

 although it is possible this may have heen supported by other means. The 

 teral elevation di' the land was probably greater than now, ami when the 

 ice melted towards the south, which it probably did rapidly, it may have 

 discharged a tremendous stream of water over what is now the narrow divide 

 between the head of Long lake and the north shore of Lake Superior. The 

 area of pot-holes, remarkable for their Dumber and great size, described by 

 Mr. Peter McKellar in a paper printed in thi- volume, is in the track which 

 would he followed by such a river. 



Some extraordinary features with reference to glaciation are presented at 

 the northeastern extremity of Hudson's hay. The northern part of the easl 

 Coast of the hay runs about due north, while the western part of the south 

 >hore of Hudson's strait runs about due west, so that the two form a right 

 angle at ('ape Wblstenholme. Projecting westward from this cape are two 

 high islands, called Digges, the Outer one lying west of the Inner, the latter 

 being separated from the cape by a narrow notch. Overlooking Hudson's 

 .-trait from < 'ape Wolstenhplme, for twenty or thirty miles eastward, is a per- 

 pendicular precipice a thousand feet or more in height. It has a nearly uni- 

 form elevation: while, looking eastward from the Hudson's hay side, the 

 plateau above it has an even outline, which appears to slope slightly upward to 

 the brink of this great precipice. The angle formed between the south side 



of Inner Digges and the main land is hounded hy high and almost perpen- 

 dicular walls of rock. The glacial movement here having heen from the 

 west ami south, it looks as if these walls had heen protected by a wedge »f 

 ice, their height having heen too great and their slopes too steep for the lower 

 part of the -lacier to surmount; while their peculiar conformation with 

 regard to each other would aid in wedging the ice in the manner supposed. 

 Ala considerable distance \<> the southeast, or directly inland from the cape, 

 -Hue mountains rise t" a height of perhaps a thousand feet above the plateau 

 which has just heen described. II' the ice-sheet moved from south to north 

 mi this plateau, B8 it did on lower lands to the southward, and if the laud 



was a- high a- it i.- ai present, there must have been a magnificent ice-fall 



over thi- precipice in glacial times. 



The gnat lake.- of the St. Lawrence and our North west Territories are all 



«.n or mar the junction of the Archean with newer rocks. The ha-in- "I 



some of them extend far below the level of the sea, or even below the bottom 

 of Hudson's bay. Although this inland sea "I' Canada is Idled with -alt 

 water, it may, geologically Bpeaking, be considered as analogous t « * the great 



lake- lather than a- forming part of t he ocean. With il- wide -hallow ha-in. 



