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NOTES UPON THE GEOLOGY OF SOME PORTIONS OF MINNESOTA, 



This offers a clear and unmistakable evidence of a rock of the same or similar formation, 

 which I can have no doubt is the western outcrop of the synclinal axis which occupies a 

 width of sixty or seventy miles. I was the more convinced of this after proceeding thirty 

 miles to the westward as far as Lake Shetek, without any evidence of other geological 

 formations except the prairie drift covering the quartzite. 



At this place I was so fortunate as to find a large quantity of pipestone, which had 

 been brought from the original locality the previous winter, and I observed among this 

 material a considerable variety of color and texture ; but in its red and mottled aspect, it is 

 precisely similar to the softer portions of the rock at Redstone Ferry on the Minnesota. 

 Were there no other information concerning the position of the pipestone, its exact resem- 

 blance to the rock at Redstone Ferry would convince one of the identity in age of the 

 formations in the two localities. 



Turning northeastward from Lake Shetek,* I explored the upper branches of the Cot- 

 tonwood River, without finding any satisfactory evidence of other geological formations. 

 Proceeding down the river as far as Saratoga,f the locality of a former settlement, which 

 is now abandoned and the buildings destroyed, I found no features of especial geological 

 interest. From Saratoga we proceeded almost directly north to Sun Lake, and thence 

 crossed the undulating prairie country to the Redwood River; and thence down thai, 

 stream to Redwood Falls. At intervals on the way we found evidence of the existence 

 of the same green clay and sand formation as that observed upon the Cottonwood below 

 the mouth of Mound Creek. At Redwood Falls a well has been dug, which penetrates a 

 similar formation; and the water has the same disagreeable taste, and is charged no doubt 

 with the same salts which render the well-water in that region unpalatable. The same 

 or a similar formation crops out at several points near Redwood Falls. In these localities, 

 the earthy coal, of a character similar to that on the Cottonwood before mentioned, has a 

 thickness of nearly three feet. An exposure of the same on the land of Mr. Flynn below 



* The authority to he furnished with an escort had expressed the object to be for explorations upon the Cotton- 

 wood Valley; and I did not feel at liberty to go beyond Lake Shetek, though the men were very anxious to go to 

 the Pipestone, and several of the scouts from the camp at Hurricane Lake and Lake Shetek volunteered to accom- 

 pany us. It was therefore with great regret that I abandoned the idea of visiting that famous locality. A few 

 days later, it was ascertained that eighty lodges of the Yankton Sioux were encamped at the Pipestone quarry. 



f All the settlements, except those near the Minnesota River, were cither destroyed by the Indians in 1862 or 

 have since been abandoned. This place was named Saratoga in reference to some copious springs, one of which 

 I examined and found to bo a fine chalybeate water. I was informed of other saline or alkaline springs, but the 

 tune at my disposal, together with the caution then necessary to bo observed in this region, prevented any exami- 

 nations beyond those having relation to the general geological features of the country. 



