BORDERING ON VERMILION RIVER 



317 



On the south side, the wall is about fifty feet in height, and thirty feet on the north 

 side. The current is very swift, and falls about twelve feet in the distance named. 

 The bearing of the rocks is east-northeast and west-southwest, and the dip 36° 

 south-southeast. There are fewer granitic intrusions here than at most of the other 

 points examined. The few veins are principally felspathic, the felspar being in 

 large lumps and crystals, and decomposing easily. The ridges are covered with a 

 thin bed of clay. Between this place and " Crane Lake Portage," one other ridge 

 was seen, with same bearing and dip. It is about thirty feet high, and has nume- 

 rous granite veins cutting across the line of strike. Where the granite intrudes, 

 the stratification of the schistose rocks is nearly or wholly obliterated. 



At Crane Lake Portage we found a high ridge of rocks, almost bare, in which the 

 relations of the granite and mica slate were very satisfactorily shown. The ridge 

 is about three hundred feet in height, and bears east-northeast and west-southwest. 

 It is traversed by granite veins, which, at some points, are from twenty to thirty 

 feet wide. These veins do not, however, maintain their width for the whole dis- 

 tance they are traceable, but divide into several separate veins, which penetrate 

 between the beds of slate laterally, which gives to the granite, in many places, the 

 appearance of being bedded, and of alternating with the beds of mica slate. These 

 veins also appear always to be wider near to and at the summits of the hills. The 

 mica slate is fine-grained, and very compact and tough between the granite intru- 

 sions, while the granite becomes very micaceous. Most of the veins contain but 

 little mica, until they become subdivided and more intimately associated with the 

 mica slate, their constituents being principally quartz and felspar, the felspar pre- 

 dominating. 



The rapids here are very difficult, and a portage has to be made of everything. 

 Where the river turns around, or, rather, cuts through the ridge just described, it 

 is contracted to twenty feet in width, and runs through a gorge, with mural walls 

 over forty feet in height, for the distance of nearly three hundred yards. From the 

 point where the portage leaves the river above the ridge, to where it strikes it 

 again, on the north side, is about a mile and a half by the course of the stream — 

 the length of the portage being estimated by the voyageurs at two u pauses." The 

 fall at these rapids, as measured by Colonel Whittlesey, is thirty-five feet. 



A little over two miles below the portage we entered a narrow detroit, which 

 leads to Crane Lake. The shores of the lake are bound with rocks, which become 

 more granitic in character, and just at the termination of the lake, low ridges of 

 granite show themselves. The dip of the schistose rocks, from the lower end of 

 Crane Lake Portage, is north, north-northwest, and north-northeast. The bending 

 and foldings of the slates by the granitic intrusions, are beautifully exhibited at 

 many points on the lake shore, and particularly at the narrow strait which con- 

 nects Crane Lake with Sand Points Lake, and called by the Indians Wa-ba-bi-kon. 

 At the entrance of this last lake the rocks are all granite (No. 531). 



At the north side of Sand Points Lake mica slate again appears, dipping north- 

 northeast, at an angle of 15°. (No. 532.) It is traversed by granitic and felspathic 

 veins (Nos. 533 and 534). A short distance further on, the dip varies from 16° to 

 44° north, and a little east and west of north. This slate is very finely laminated, 



