36 Wisconsin and Missouri Lead Region. 



horizontal, until by tracing them some miles, a prevailing dip to 

 the south is discovered. 



The lead region is a rolling hilly country, the hills sometimes 

 covered with an open growth of oak, but as often entirely free of 

 timber, and clothed with the tall prairie ^grass only. The sum- 

 mits maintain a general level, except where it is broken by the 

 "natural mounds," (the two Blue mounds, the Platte mounds, 

 Sinsinava mounds, &c.) which rise several hundred feet above 

 it. In these the limestone appears more siHceous than is noticed 

 elsewhere, and its superior hardness may in part have been the 

 cause of these mounds remaining like monuments of the devas- 

 tating currents that must have given the surface around its pres- 

 ent form; while the huge blocks, tipped out of their horizontal 

 position, lie on the steep sides as additional evidence of the wast- 

 ing waters. Yet these are the only evidences that such a force 

 has been in operation ; for in the western part of Wisconsin, there 

 are no primary bowlders, no loose rocks but those which once 

 evidently formed a part of the formations on which they now 

 repose ; in the eastern part of the territory, however, and to the 

 west in Iowa, such bowlders are not wanting. Whether this 

 region may have been in part protected by the high lands to the 

 north of it, and the progress of the bowlders been thus intercept- 

 ed and turned aside, must be determined by more extended ob- 

 servations. This supposition is rendered more plausible by the 

 unusual course of the Wisconsin river, it suddenly turning from 

 a south to a west direction. In its valley, however, where it 

 flows towards the west, no bowlders are found except the small 

 pebbles brought down by the river itself. 



Throughout the extensive tract defined as the lead region, lead 

 ore may be sought for with prospect of success on every town- 

 ship and on almost every square mile. And fortunately it is so 

 well watered, and the little streams have so rapid a fall, that 

 power for furnaces may almost always be obtained near the mines. 

 New discoveries are continually made, and with every one fur- 

 ther light is thown upon the true character of the ranges of fis- 

 sures containing the lead and copper ores ; by which result they 

 can be traced with greater certainty from one tract to another, 

 without depending entirely on the present imperfect system of 

 "prospecting." 



