98 ELEVENTH REPORT. 



abuts directly against the ore. Sometimes the ore comes quite to the surface 

 but it is usually covered by from one to several feet of clay. All of the 

 mining is done by hand. The larger nodules called "rock" ore, some of 

 which need to be broken up by blasting, are picked by hand from the clay 

 and sand in which they are embedded but the greater part of the 

 ore is mined with the impurities in which it occurs and separated by 

 washing in barrel washers. The following is the analysis of a three month's 

 average sample of "rock" and "wash" ore: 



Fe SiO^ AI3O3 CaO MgO P vS Mn 



43.6 24.00 2.3 .58 .30 .14 .018 .80 



The Cady Deposit. 



The Cady deposit is 2^ miles northwest of Elmwood and southeast of 

 Spring A'^alle}^ about 5 miles. It covers several acres on the top and upper 

 slopes of a high 2-idge that rises steeply above the valley of Cady Creek. 

 (Fig. 2.) As in the Oilman deposit the ore rests on the Magnesian limestone. 

 At the time of the writer's visit the deposit had not been opened but the ore 

 was exposed in numerous pits and trenches. According to Mr. W. H. Foote, 

 at one point a shaft was sunk through 80 feet of ore and struck a face of 

 limestone at that depth which was at an angle of 60 degrees with the hori- 

 zontal. Ore was followed down this face for 40 feet more with no bottom. 

 The following analyses indicate the character of the ore in this shaft. 



Analyses of Cady Creek Ore. 



Depth Fe SiO., Mn Phos. 



Blue lump ore 10 ' 59 . 12 9 2 . 03 .075 



Brown lump ore 10 ' 49 . 96 14.33 .83 . 073 



Brown hematite 16 ' 47 . 79 20 . 5 1 . 39 .078 



22' 32.96 45.25 2.13 .076 



28' 46.56 22.17 2.47 .077 



34' 52.02 11.82 2.51 .054 



40' 37.91 35.34 1.82 .068 



45' 55.11 1.73 .062 



50' 53.56 2.72 .062 



55' 52.02 2.25 .062 



60' 52.22 1.91 .068 



65' 54.18 1.33 .060 



The Cady ore contains a somewhat higher per cent of iron, has a greater 

 proportion of "rock" ore, and is associated with a lesser amount of impurities 

 i. e., sand, clay, etc., but is otherwise exactly similar to the Oilman ore. 



Oeology and Topography. 



The Potsdam sandstone, of Upper Cambrian age. underlies the valleys 

 and the lower hill slopes. The uplands are formed by the Magnesian lime- 

 stone of Ordovician age. The strata are conformable and nearly flat lying. 

 The position of the area with reference to the axis of the broad central and 

 southern Wisconsin anticline indicates an average slight dip of the strata 

 toward the southwest. 



The topography is that of the maturely dissected plateau, which is 

 characteristic of the larger part of the driftless area of the Upper Mississippi 



