10 



1. It has been suggested that there may be a limestone 

 rioor for this part of the lake. 



2. The limestone might have been derived from the 

 Hudson Bay slope, where such rocks occur. 



3. The limestones are erratics from the Red River 

 Valley. 



As to these view:^ there is no evidence of a limestone floor 

 for Lake of the Woods ; in fact, there is every probability against 

 it. In regard to No. 2, it would seem impossible to imagine 

 any agency by which the great region of rocky country be- 

 tween this region and Hudson Bay could have been overcome. 

 The third supposition is plainly most reasonable. In the 

 glacial period we know that a great glacial lake covered the 

 Red River Valley and extended to the east shore of the Lake 

 of the Woods. The glacial action in the Red River Valley 

 was very great, and no doubt fragments of the limestone were 

 carried southeastward from it to the basin of the Lake of the 

 Woods. 



MINING. 



The contorted strata of the Huronian rocks, thrown 

 about as they have been by granitic intrusions, naturally had 

 many crevices, faults, fissures, broken seams, cracks and open- 

 ings in their structure. The intrusive rocks would liberate in 

 their upheaval great bodies of lava, steam and boiling water 

 from the vast depths below. These would have the metals in 

 a state of solution. The crevices and faults of the Huronian 

 would be filled and gorged with the gaseous, or liquid, heated 

 matters 



From the wide-spread chaiacter of the mineral substances, 

 such as sodium, potassium, manganese, iron, copper, and even 

 gold and silver in sea water, and in many sea animals and 

 plants, it may be learned what the waters thrown up from the 

 great depths would contain. The cooling down of the mate- 

 rials thus carried in by water and steam makes the veins. 

 The kind and character of the vein depends on the shape of 

 the crevice or opening when the intrusive solid matter is de- 

 posited and solidified. 



