716 GEOLOGY AND TOPOGRAPHY OF THE LEAD REGION. 



"The company commenced work in 1849, and on the present range m May, 1874. 

 They are now operating a steam pump on what is supposed to be a continuation of the 

 South digging range. The product from June 1, 1873, to Maa-ch 1, 1876, is as follows: 

 1873, 377,120 pounds; 1874, 201,966 pounds; 1875, 318,690 pounds; 1876, 153,720 

 pounds." 



Silverthorii Mine. N. W. qr. Sec. 32, N. E. qr. Sec. 31, T. 2, R. 2 E. The great- 

 est thickness of Galena limestone found on the ridge was about one hundred feet. The 

 ground is drained by a level ran in the carbonaceous shale, on the top of the Blue 

 Hmestone, which has here a very great thickness, being nowhere less than two feet, and 

 in some places seven and a half feet tliick. It seems in this mine to replace the pipe- 

 clay opening. It is very easy to work, and consequently this level has been compara- 

 tively inexpensive. This shale, when dried, burns with a bright yellow flame and much 

 smoke unto, the carbon is exhausted, but owing to the amount of calcareous matter it 

 contains, it is not much reduced in bulk. These diggings produced in 1871, 200,000 

 pounds, and in 1872, about 100,000 pounds. Their product in previous years could not 

 be ascertained. Work was suspended on them in 1875. An analysis of lead ore from 

 the Silverthorn mine gave the following results: Lead sulphide, 97.06; metallic lead, 

 84.07; insoluble siKcious residuiim, 1.76. 



Dry Bone Diggings.' Situated on the S. W. qr. of the S. E. qr. and the S. E. qr. 

 of the S. W. qr. of Sec. 4, T. 1, R. 2 E. The ranges here run in nearly an east and 

 west direction. The diggings are situated in the lower strata of tlie Galena limestone; 

 the top of the Blue limestone is found a short distance down the stream. Although 

 shallow, these diggings have been very productive of zinc ore, and are still successfully 

 worked. 



Irish Diggings. Sec. 2, T. 1, R. 2 E. These diggings have not been worked for 

 many years on account of water, but were fonnerly very productive and were abandoned 

 with ore going down in the crevices. The greatest thickness of Galena limestone on 

 tliis ground is about 150 feet. They could be roadily unwatered by means of a level 

 from some point on the Shullsburg branch. 



Meloy and Fox. In the early part of the year 1875, that part of the Irish Diggings 

 known as the Findloy Cave range was leased by Messrs. E. Meloy and M. A. Fox, of 

 ShuUsburg-. It is situated on the N. E. qr. of Sec. 2, T. 1, R. 2 E., and comprises 99 

 acres of land, lying about a mile northeast of the village. The range was worked du- 

 ring the months of April, May and June, 1875, and in November of that year a steam 

 engine and pump were erected, and it has been worked continuously to the present time 

 (November, 1876). The pump shaft is now about 80 feet deep. Water is discharged 

 into an adit connecting with the shaft at 20 feet below the surface, at the rate of 150 

 gallons per minute. The course of the vein is N. 7° E., having a dip to the eastward 

 of four feet in one hundred. The distance between the walls of the vein or crevice va- 

 ries from two and a half to seven feet, the space between them being filled vidth the 

 vein matrix common to this neighborhood. The bottom of the pump shaft is six feet 

 below the top of the flint beds (see section on page 715). The vein appears to continue 

 downwards, the filling of the crevice being loose and allowing the water to pass readily 

 through it. 



After sinking the pump shaft, the vein was drifted in, a distajtice of 60 feet to the 

 northward; in the course of runnmg this cbift, 100,000 pounds of ore were extracted. 



The foregoing remarks show the condition of the mme in March, 1876. The produc- 

 tion since then we have not learned. 



This range was worked more than 30 years since, with a two-horse pump, as deep as 

 water would permit, and large quantities of lead ore were obtained. These diggings 

 could be unwatered to a nmch greater depth by means of a level from some point on tlie 

 Shullsburg Brajich. 



