Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/36

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Arthur's Landing. At this point the vein strikes nearly east and west, and is almost vertical. Its width is about 22 feet ; and the vein-stuff consists mainly of calc spar. Quartz and fluor spar are of occasional occurrence ; and there is a considerable quantity of iron pyrites. The silver is present both in the native form and as sulphide, some specimens being extremely rich. The vein cuts through hard black shales, but has a large mass of hornblendic trap about 50 feet to the south. The vein, however, does not run exactly along the strike of the beds, so that in following it to the west it comes ultimately to have the trap as its foot-wall. Like almost all the veins of the north shore of Lake Superior, the Shuniah lode is of a brecciated character, containing numerous fragments of the country rock. The Shuniah vein admits of being traced for several miles towards the east ; and I entertain no doubt that the so-called 3 A and Leek mines are both situated upon this lode. In passing towards the east, however, the vein diminishes somewhat in thickness, and the vein-stuff becomes siliceous instead of being calcareous. At all points where the vein has been opened it has been found to contain silver, generally in the native form, associated with silver glance. At the 3 A location the vein also contains a considerable quantity of copper-nickel ; and at the Beck or Silver Harbour Mine the silver is commonly associated with zinc- blende.

The gold-districts of Shabendowan, Round Lake, and Jackfish Lake are situated nearly to the west of Prince Arthur's Landing, the first of these being distant about 60 miles from Thunder Bay. Lake Shabendowan is reached by the so-called " Dawson Road," the commencement of the celebrated " Red-River route," the length of the road being about 47 miles. The entire district travelled over by the " Dawson Road," between Thunder Bay and the foot of Lake Shabendowan, is of an undulating character, numerous rugged bosses of rock everywhere protruding in ranges which have a prevailing N.E. and S.W. direction. Where not burnt, the country is covered with a dense timber ; but the trees are of small size, totally unfit for " lumbering "-purposes. They consist mostly of spruce, tamarack, white birch, poplar, bastard pine, and pitch-pine ; but the oak, white and red pine, and maple are altogether wanting. The fundamental rocks of the entire region everywhere exhibit unmistakable proofs of the passage over them of enormous masses of land-ice. Every rock-exposure is moutonnee, polished, and striated ; and we must conclude that the former condition of the country was very similar to that now obtaining in Greenland. The general direction of the striae is N. and S. ; but there is a minor set of grooves occasionally visible, the direction of which is nearly east and west. The greater part of the country is thickly covered up with drift, containing numerous and often large boulders of syenite, granite, gneiss, greenstone, slate, &c, all of which appear to have travelled from the north towards the south. In some places also (as near the bridge over the Kaministiquia liver) there are large masses of stratified drift.