The Pipestone of Devils Lahe. 253 



with the formation containing the pipestone of Minnesota, only 

 forty miles distant, and is identical in its aspects with the quartz- 

 ite of Devil's Like. It has the same color, hardness, completeness 

 of metamorphism, ripple marks, and tendency to degrade in cubi- 

 cal forms; the last a notable feature of the rock at Devil's Lake 

 and equally characteristic of the quartzite in which the Catlinite 

 is found, as it is described by Nicollet. These localities have not 

 only the quartzite apparently identical, but also the pipestone. I 

 found a mottled, yellow and red pipestone cropping out at the Big 

 Sioux, associated with the quartzite. A fourth location of the 

 pipestone, noted by Nicollet and later by Owen, is at the head 

 waters of the Cedar, a tributary of the Chippewa, on Sec. 27, T. 

 35 N., R. 10 W., of the public survey, as I am informed by the 

 owner of the land, Mr. EL. C. Putnam of Eau Claire. Here, too, 

 it is associated with quartzite. 



The concurrence of these facts suggested to me the importance 

 of identifying thetalcose beds of Devil's Lake with the pipestone 

 of the other localities. Pipestone is a rare rock. Its appearance in 

 these widely separated centers, with like associations, I take to 

 indicate a common age and origin for the containing quartzites, 

 respecting which there has been much discussion and still exists 

 a diversity of views. It would seem to have been satisfactorily 

 determined by Prof. Irving that the quartzite of Devil's Lake is 

 older than the Potsdam sandstone. The junction of the quartzite 

 with the inferior formation has not been discovered in any of the 

 localities herein mentioned. That evidence would be conclusive 

 of the question in the particular case. While awaiting it, some 

 authorities refer the Minnesota and Dakota formation to the Pots- 

 dam and others to the Huronian period. My thought is, that 

 whatever the age of one of these formations, all are referable to 

 the same epoch; that they are allied by the pipestone; and that 

 this connecting link establishes the probability that these rocks 

 are the result of the same cause or set of conditions, operating in 

 that dawn of the continent's history when literally the dry land 

 first appeared. 



In the vicinity of Devil's lake the pipestone is found in but 

 few places, and the exposure is nowhere extensive. It conforms 



