8 GEOLOGICAL SURVEY OF WISCONSIN. 



was requested to give attention to the question of tlie age of the red 

 sandstone and accompanying shale of the counties to be examined; 

 whether the Archaean rocks are of different ages; and to the disturb- 

 ances of the strata in the vicinity of the metal-bearing ranges, involv- 

 ing important questions regarding the proper system of mining. 



His report, herewith submitted, will be found to contain ample de- 

 tails of the beds of silicious magnetic iron ores forming what is 

 known as the Penokee Iron Range, with numerous analyses of the 

 ores, including all information necessary for a proper understanding 

 of the extent and value of these important ore beds. Other details 

 brought forward in this report, showing what had previously been 

 done in exploring this interesting region; its topography, surface, 

 general, special and economical geology; its agricultural features, 

 timber, etc., will be found equally interesting and valuable. These 

 explorations, made so early in the season, were not accomplished with- 

 out the patient endurance of much suffering and hardship, arising 

 from the clouds of musquitoes, and from unfavorable weather. 



Prof. Irving also made a partial examination of the iron ore beds 

 at and near the Black Eiver Falls, in Jackson county. 



Pkof. Chambeelin's Party. — To Prof. Chainberlin was assigned 

 the duty of surveying that portion of the state lying immediately 

 west of the line of outcrop of the Niagara or Clinton group of rocks, 

 from the south line of the state through the counties of "Walworth, 

 Jefferson, Dodge, Fond du Lac, Calumet and Outgamie to the south- 

 ern limits of the crystalline Archtean rocks in Shawano county; and 

 upon his return route, to examine the outcrops of the lower strata lying 

 west of that line. He would thus be led to examine the important 

 iron beds, now so extensively mined at Iron Eidge, the artesian wells 

 from which water flows so abundantly at Fond du Lac and elsewhere, 

 and the highly interesting localities of quartzite in Dodge and Jeffer- 

 son counties. He would also be in the midst of some of the most 

 striking features of the glacial and modified "drift," with their "pot- 

 ash kettles," gravel hills .and parallel ridges. 



On the twenty-third day of June, work was commenced by thus 

 party under the immediate direction of Prof. Chamberlin, aided dur- 

 ing portions of the time by Messrs. L. C. Wooster, F. H. King, N, 

 D. "Wright, Samuel Shaw and G. L. Merriman. 



They reached Keshena, in Shawano county, early in September, and 

 returned to Beloit by the last of that month. Some further explora 

 tions were afterwards made by Prof. Chamberlin in person, as men- 

 tionedin-his report. 



