APPENDIX. 321 



ingfish lliver, and appears to dip at Isle aux Trains, about twenty- 

 miles northeast. The scenery is peculiarly soft and pleasing in 

 passing the Huron Islands, a granitic group, and directing the 

 view, as in the sketch, to the coast and the rough granitical hills 

 rising behind Huron Bay. The strata are level, as shown above, 

 around the Bay of Presque Isle and Granite Point, and continue 

 so, resting on the roots of the granitical tract of the Totosh^ or 

 Schoolcraft, and Cradletop Mountains, and at Point aux Beignes, 

 and Keweena Bay. This level position of the rock is preserved 

 to the south cape of the shallow bay of the Bete Gre, on the 

 north, at which the trap-dykes of the peninsula first begin ; and 

 so continues after passing that rugged coast of the vitreous series 

 of that remarkable point, to and beyond Eagle Eiver and Sandy 

 Bay, in the approach to the portage of the Keweena. 



The same horizontality is observed on the headland west of it, 

 and upon all the points and headlands to Misery and Firesteel 

 Rivers and the mouth of the Ontonagon. The trap-dyke of Ke- 

 weena crosses this river about ten miles, in a direct line, inland. 



At Iron Eiver, we observe a stratum of compact gray grau- 

 wacke, over the hackly bed of which that river forces its way 

 during the spring months, and stands in tanks and pools during 

 the summer. On reaching the foot of the Porcupine Mountains, 

 the sandstone, which is here of a dark chocolate color, with quartz 

 pebbles of the bigness of a pigeon's egg^ and organic remains of 

 palaozoic type, is found to be tilted up into nearly a vertical posi- 

 tion, as shown in the sketch. The grauwacke reappears, in a most 

 striking manner, at the Falls of Presque Isle River, where the 

 whole mass of water precipitated from the highlands drops into 

 a vast pot-hole, a hundred feet wide and perhaps twice that depth. 

 The whole upper series of rocks, from the Porcupine Cliffs west 

 to the Montreal River, is a conglomerate. At the Falls of the 

 Montreal, the river drops over the vertical edges of the red sand- 

 stone. Beyond the Bay of St. Chares, at Lapointe Chegoimigon, 

 masses of sienitic mountains arise, which have their apex near La 

 Riviere de Fromboise. 



The Islands of the Twelve Apostles, or Federation Group, 



appear to be all based on the sienitic or trap, with overlying red 



sandstone ; which latter again reappears on the point of the 



entrance into Fond du Lac Bay, and marks its southern coast, till 



21 



