158 Feather stonhavgWs Geological Report. 



Being desirous of examining the country from Prairie du 

 Chien to the mouth of the Missouri, more in detail than 1 

 should have been able to do if I had taken my passage in the 

 steamboat, I continued on to Dubuque'sand the town of Galena 

 in my canoe. Sulphuret of lead is found in various places 

 between Prairie du Chien and Cassville, a new settlement on 

 the left bank of the Mississippi. At Dubuque's lead mines 

 the limestone appears identically the same with the galenifer- 

 ous beds of Missouri. The fossils also are the characterstic 

 fossils of the carboniferous limestone. The galena itself, 

 however, differs in appearance from that which constitutes the 

 solid and brilliant bands* of sulphuret in the Missouri mines. 

 There, although it has an evident tendency to separate into 

 cubes, the lines of cleavage are generally obliterated, whilst 

 here the sulphuret consists of aggregates of perfect cubes, of a 

 very dull and rubbly appearance, and lying in loose masses in 

 cavities of the limestone beds, mixed up with ochreous earth. 

 1 found this to be the universal state of the metallic beds also 

 on the left bank of the Mississippi. In Missouri the veins of 

 galena are exceedingly bright, and are encased in wet, waxy, 

 red, argillaceous matter, whilst in the galeniferous region of 

 this part of the country, some electric action seems to have 

 dried up the argillaceous matter, and to have separated the 

 metal into cubes, and broken it up into masses. In the neigh- 

 borhood of the town of Galena, I perceived the veins went 

 very much into those pockets common to metallic countries ;f 

 here they appear to prevail through extensive areas of coun- 

 try ; shafts are sunk to great depths through the dry red earth, 

 and the masses of cubical sulphuret are always found in the 

 condition I have described. I think it very probable that the 

 lead formation of this part of the United States extends to the 

 north far beyond the places where excavations are now car- 

 ried on, but the activity, perseverance, and great respecta- 

 bility as to character and resources of the population engaged 

 in the lead business of the Galena district, will in time lead 



* Report 1835, p. 48. f Report 1835, p. 49. 



