MINES SHULLSBURG DISTRICT. 715 



able of the limestone seems to have been removed by currents of water running through 

 the opening, thus permitting large and small irregular masses to fall from above, and 

 filling the interstices with tho fine insoluble residuum of sand. 



In connection with this irregularity was noticed a remarkable "chimney " about 36 

 feet long by 20 feet broad, and extending upward further than has yet been followed. 



It was originally filled with loose masses of galenite rock and sand. In the ground 

 on this ridge the strata dip on both sides toward the north and south line between Sees. 

 14 and 15, on the west side about four feet in a quarter of a mile, and on the east side 

 one foot in thirty rods. The ground is drained by a horse-pump into a level a short 

 distance below the surface. The mine produces very handsome cabinet specimens of 

 galenite and caloite, in the form of dog-tooth spar. 



The following section will serve to convey a general idea of the arrangement of the 

 strata on this ridge : 



Soil and clay 6 to 10 feet 



Galena limestone 100 " 



Flint bed 4 to 8 " 



Green bed to clay bed, including the opening 14 to 18 " 



Galena limestone to top of Blue limestone 65 " 



Total average thickness 195 " 



This may be compared with the section taken at New Diggings, and given on page 

 710 of this report. Reckoning upwards from the top of the Blue limestone to the top of 

 the green bed, or cap of the Shullsburg opening, the distance is found to be about 80 

 feet, and in the New Diggings section, from the top of the Blue limestone section to 

 the top of the flinty rock, which is the cap of the third or main opening, the distance is 

 82 feet. 



This establishes an identity of geological position of these two points. Measuring 

 downward from the cap in the Shullsburg opening, its average distance is found to be 

 sixteen feet to the bottom of the opening. In the New Diggings section the same dis- 

 tance includes all that lies between the top of the third and bottom of the fourth open- 

 ing, and finally each is underlaid by about the same thickness of unproductive rock. 

 The correspondence between these openings is thus very distinctly marked. The un- 

 productive beds in the New Diggings openings seem to disappear on going eastward, 

 and finally the openings unite on reaching Shullsburg. 



In regard to the production of these diggings, it is estimated that the S. hf. of Sec. 10, 

 and the N. W. qr. of the N. W. qr. of Sec. 14, being an area of one mile long on a 

 course S. 70 E., and three-quarters of a mile wide, including the McNulty and Rick- 

 ert's diggings, have produced since the commencement of mining operations not less 

 than 100,000,000 pounds. 



The preceding information in regard to the mine of Rickert, Stephens & Co. was ob- 

 tained at the time I examined them in June, 1873. Since then I have recently received 

 the following information concerning them from Mr. John E. Hoover, of Shullsburg, to 

 whom I am also indebted for valuable information relative to the Irish Diggings and 

 the McNulty mine : 



" The bearing of the crevice on which we (Rickert, Stephens & Co.) are now working 

 is due east and west. The mineral is found about 12 feet below the green bed or cap, 

 and is mixed with sulphur (pyrites). The rock is different from any before taken out of 

 the mines in this section. It is a dark blue, and mixed with sulphur and flint, and is 

 very hard. In the opening there is copper rust or verdigris mixed with large balls of 

 sulphur. Dog-tooth spar or tiff is also found in large quantities, most of which is 

 attached to the mineral. 



