EEPOET OF PEOGEESS AND EESTJLTS, 



FOR THE YEAR 1S75. 1 



BY O. W. WIGHT. 



In compliance with a requirement of the act " to provide for a com- 

 plete Geological Survey of Wisconsin," approved March 19, 1873, I 

 have the honor to report the progress made during the third year of 

 the survey. 



BRIEF HISTORY OF PREVIOUS GEOLOGICAL SURVEYS IN WISCONSIN. 

 The first geological survey undertaken by the government of the 

 United States was instituted by the appointment of G. W. Feather- 

 stonhaugh, Esq., by the war department, with instructions to make a 

 reconnoissance " of the elevated region lying between the Missouri 

 river and the Red river, known under the designation of the Ozark 

 mountains." It was in the early part of the year 1834. In the win- 

 ter of 1834-35, that gentleman visited the lead mines of Missouri and 

 made a perfectly worthless report. The next year Mr. Featherston- 

 haugh was employed by the government under the title of United 

 States Geologist to explore the region between the St. Peters river 

 and the Missouri, and to make a general reconnoissance of the north- 

 west. He referred the whole series of Lower Silurian rocks in the lead 

 region of Wisconsin and up the river to the falls of St. Anthony and 



1 The fullest opportunity has been offered the author of this report to revise it for this 

 volume, but not having been accepted, the delicate duty has devolved upon very unwfl- 

 ing hands. Certain portions of an annual report necessarily refer to matters of transient 

 importance and are of little subsequent value. Such portions of this report have been 

 omitted, viz. : A financial statement, a business account of the work in Oconto county, 

 and an outline of the work remaining to be done. The law authorizing the survey, 

 which has been previously given, and the reports of assistants prepared by themselves, 

 are also omitted, as in the case of the reports of 1873 and 1874. I have deemed myself 

 under obligations to publish everything of a geological nature, even where dissenting 

 from the views presented. T. C. C. 



