62 



Miles and 

 Kilometres. 



103. m. A few miles east of Havelock Black River 



165.7 km. limestones are exposed, and the pre-Cambrian 



complex also makes its first appearance about 

 one-quarter of a mile north of the railway track, 

 where trap is developed on the surrounding 

 hills, and is being quarried and crushed for 

 road metal. 



122.8 m. Between Havelock and Ivanhoe flat-lying 

 197.6 km. limestone is exposed, except where covered by 



extensive swamps which occur in this area. 

 These Paleozoic limestones continue to within 

 132. m. a few miles of Tweed, and the surface of 

 212.4 km. the country presents a striking appearance owing 

 to the numberless boulders of the limestone 

 which cover it. At Tweed pink granite gneiss 

 and Trenton limestone are exposed. 



Ivanhoe to Madoc. 



The village of Madoc, which lies about seven miles north 

 of the Canadian Pacific railway, is connected by wagon road 

 with Ivanhoe station, and for four miles north of the 

 station the road passes over horizontal beds of Ordovician 

 (Black River) limestone. The northern face of this lime- 

 stone presents a steep escarpment, the latter presumably 

 caused by a fault. To the north of the escarpment the great 

 expanse of the pre-Cambrian shield is entered, and the vil- 

 lage of Madoc is seen resting on the southern fringe of these 

 ancient rocks. The topography of the country underlain 

 by the Black River limestone is flat or gently rolling, while 

 that presented by the complex peneplain of the pre-Cambrian 

 is comparatively rugged. 



