TOPOGRAPHY. 99 



outbursts. There was indeed tlie gradual elevation and depression of 

 the surface and probably some little flexure of the crust, and there 

 are at two or three points, indications of faulting; but in general, the 

 region has been free from violent agitation, and owes none of its sali- 

 ent topographical features to such causes. 



Having thus briefly considered the general methods by which the 

 present aspect of the country was produced, we may now more satis- 

 factorily examine its special features, and if the reader will have re- 

 course to Plate IV of this volume, and, for minor details, to the 

 accompanying atlas, it will relieve us mutually of the wearisomeness 

 of mere elementary geographical details, while it contributes to a 

 clearer and more vivid understanding of the subject. 



]STo part of Wisconsin can properly be said to be mountainous, nor 

 does it, over any considerable area, sink to a dead level. It presents 

 the golden mean in a gently undulating diversified surface, readily 

 traversible in all directions by the various highways of commu- 

 nication. The eastern district under consideration contains the more 

 level portions of the state, but presents at the same time much of di- 

 versity and many most interesting topographical features. 



Setting aside minor details, the state presents two general slopes, 

 a short, abrupt declivity northward to Lake Superior, and a long, 

 gentler incline southward. Through the center of this southward 

 slope there extends a moderate elevation a low anticlinal axis 

 giving a southeasterly and southwesterly inclination to the strata on 

 either side. The district under consideration is wholly confined to 

 the southeasterly slope. 



The symmetry and simplicity of this system is however traversed 

 in a peculiar manner by a diagonal valley occupied by Green Bay 

 and the Fox and Wisconsin rivers. This feature of the general sur- 

 face of the state enters, in an interesting way, into the topography oil 

 our district, and from its commercial importance demands attention. 

 This valley, including its extension into Michigan, is occupied by the 

 waters of Green Bay for about one hundred miles, with an average 

 breadth of about twelve miles. The bay projects into Wisconsin 

 about seventy miles beyond Porte des Morts at the extremity of the 

 peninsula, and about forty-five miles beyond the mouth of the Me- 

 nomonee river, which forms the state boundary. 



This valley is abruptly limited on the east side by precipitous rocky 

 cliff's rising from 100 to 200 feet above the Bay. From the crest of 

 these cliffs, the land slopes toward Lake Michigan. On the opposite or 

 wes-t side of the valley, the surface rises very gradually for 20 to 30 

 miles, beyond which the slope becomes somewhat steeper. The Bay 



