1854.] BIGSBY GEOLOGY OF RAINY LAKE. 219 



On the east shore, for some miles north of Parry Strait, dark 

 greenstone-slate and gneiss occupy the country conformably with each 

 other, granite here and there emerging from their midst. The gneiss 

 has imbedded in it large masses of hornblende such as are noticed 

 elsewhere, which also run into it in seams, in all directions. 



From the north end of Otterberry Lake to Point Dalhousie (about 

 twelve miles), the mainland consists of dark greenstone and chloritic 

 slates, with some syenite at the bottom of Barclay Bay. 



The chloritic slate of an island two miles N.E. of Point Dalhousie, 

 marked by a fine grove of pines, is so quartzose as to become a horn- 

 stone. It has many veins and masses of white calcspar. 



Fourth Division. — The fourth district includes the fifty-two miles 

 of coast from Point Lyon, eastwardly, to Point Franklin. 



It is almost wholly occupied, as far as I could see, by both broad 

 and narrow alternations of greenstone- and chlorite-slates, in about 

 equal quantities, and of the kinds common on this lake. The former 

 is often in very thick strata, and is traversed by veins of white quartz 

 and chlorite-earth ; the latter being so soft as to be carved into images 

 by the Indians. Chlorite-slate is in particular abundance at the north 

 angle of Seine Bay. 



Both rocks are conformable ; their strike being to the E.N.E. or 

 N.E., with a northerly or perpendicular dip. They have been little 

 aifected, in trend at least, by eruptions of granite, and are in fact con- 

 tinuations of the same strata some miles across the lake, on its south 

 shore. 



It has yet to be stated that the bottom of Barclay Bay, three and 

 a half or four miles broad, is based on syenite, which is in connexion 

 with the granite region of the East Arm on the north. 



Fifth JDivision. — At the distance of two miles W.N.W. of Point 

 Franklin, we enter our fifth division. It comprises the S.E, end of 

 the lake. 



The greenstone-slate here begins, as we see in coasting along, to 

 alternate with dark syenitic gneiss, and then appears no more east- 

 wards, being replaced entirely by gneiss with a strike varying from 

 E.N.E. to E. by N., the dip being either perpendicular or northerly 

 at a high angle. 



About two miles N.W. of Cormorant River, great seams and tortuous 

 veins of white granular granite everywhere traverse the gneiss, with- 

 out alteration of the latter; and all around the above river, the countiy 

 is studded with hummocks and bosses of granite with (to my eye) 

 confused intervals of gneiss among them. 



This continues, with imbedded masses of hornblende (as seen in 

 the west of the lake) in either of these rocks, past Wah-chusk Biver 

 to Point Mackenzie (eight miles), where, southward for seven miles, 

 to Stokes Bay, numerous broad intercalations of a beautif\d silvery 

 mica-slate are met with among the granitic and gneissoid ridges. This 

 handsome slate is thickly spotted with small scales of black mica, and 

 fine granular quartz and felspar, both white. 



From Stokes Bay, along a low coast, through Hale Bay (almost 

 filled up with densely wooded islands) to Perch Biver, granite con- 



VOL. X, — PART I. Q 



