S42 APPENDIX. 



2. Lead. 



The only ore of lead known to exist within the limits to which 

 these remarks are confined, is the sulphuret. In the year 1780, 

 Peosta, a woman of the Misquakee, or Fox tribe of Indians, dis- 

 covered a lead mine upon the west banks of the Mississippi, at 

 the computed distance of twenty -five leagues below Prairie du 

 Ghien, which the Indians, in 1788, gave Julian Dubuque a right 

 to work. This permission was partially confirmed by the Baron 

 ue Carondelet, Governor of Louisiana, in 1796. No patent was, 

 however, issued ; but Dubuque continued to prosecute the mining 

 business to the period of his death, which happened in 1810, when 

 the mines were again claimed by the original proprietors. 



The ore is the common sulphuret of lead, or galena, which Du- 

 ""buque stated to have yielded him seventy -five per cent, in smelt- 

 ing in the large way. He usually made from 20,000 to 40,000 

 pounds per annum. 



I made a cursory visit to these mines, and found them worked 

 by the Fox Indians, but in a very imperfect manner. They cover 

 a considerable area, commencing at the mouth of the Makokketa 

 Iliver, sixty miles below Prairie du Chien. Traces of the ore are 

 found, also, on the east bank of the Mississippi at several points. 

 It occurs disseminated in a reddish loam, resting upon limestone 

 rock, and is sometimes seen in small veins pervading the rock; 

 but it has been chiefly explored in diluvial soil. It generally 

 occurs in beds having little width, and runs in a direct course 

 towards the cardinal points. They are sometimes traced into a 

 crevice of the rock. At this stage of the pursuit, most of the 

 diggings have been abandoned. Little spar or crystalline matrix 

 is found in connection with the ore. It is generally enveloped 

 by a reddish, compact earth, or marly clay. Occasionally, masses 

 of calcareous spar occur; less frequently, sulphate of barytes, green 

 iTon earth, and ochrey brown oxide of iron. I did not observe 

 any masses of radiated quartz, which form so conspicuous a trait 

 in the surface of the metalliferous diluvion of the mining district 

 of Missouri. 



Sufficient attention does not appear to have been bestowed, by 

 mineralogists, upon the metalliferous soil of the Mississippi Valley. 

 It is certainly very remarkable that such vast deposits of lead ore, 



