PEEVIOUS WORK OIv" FELCH MOUNTAIN RANGE. 377 



horizontal sandstones, whicli has ah'eady been mentioned as characterizing the 

 Menominee hills, gives a somewhat more even character to the crest lines, and in 

 places produces a strikingly diiiereut profile (p. 72). 



As stated by Major Brooks in a footnote on p. 157, the facts contained 

 in the chapter on the Menominee iron region were derived largely from the 

 surveys and explorations of Prof. R. Pumpelly and his assistant. Dr. H. 

 Credner. The following passage is the most important statement concern- 

 ing the Felch Mountain area, or the "North Range:" 



The north iron belt or range has a course nearly due east and west, and is all 

 embraced, so far as known, in the south tier of sections of T. 42, Rs. 28, 29, and 30. 

 The most easterly discovered exposure of ore, known as the Felch Mountain, is in the 

 N. J of sees. 32 and 33, T. 42, R. 28. Traveling due west, fragments of iron ore are 

 found in NB. J of sec. 31, T. 42, R. 28; after which no absolute proof of the presence 

 of iron is found (although it is probably continuous) until we reach sec. 31, T. 42, R. 29, 

 where, in the center of tbe section, is an immense exposure of iron ore in an east- west 

 ridge, which can be traced westerly halfway across section 36 of the next township. 

 The natural exposure of ore on section 31 is larger than at any other point in the 

 Menominee region, and the quality is as good, if not better, so far as can be judged by 

 surface indications. Magnetic attractions and iron bowlders found farther west and 

 southwest on this range prove its extension in that direction. Whether the westerly 

 course continues, or whether it curves to the southwest, as seems probable from the 

 position of the lower quartzite and local magnetic attractions in the northwest part of 

 T. 41, R. 30, has not been determined. The latter hypothesis is most iu accordance 

 with the known facts, although the southeast dip of the quartzite on sections 17 and 18, 

 observed by Dr. Credner, is not explained. If this hypothesis is true, the iron range 

 should cross the Menominee somewhere in sees. 24 or 25, T. 41, R. 31, into Wisconsin. 

 There can be little doubt but that the north and south belts belong to one geological 

 horizon, hence somewhere come together (pp. 159-160). 



A geological section through the north range on the line between Rs. 

 29 and 30, T. 42, is given, and is also represented as section CC on Atlas 

 Plate IV. The succession from south to north is as follows: 



Grranite. 



Quartzite. 



Interval. 



Marble. 



Iron-ore formation. 



Interval. 



Marble. 



Interval. 



Granite-gneiss and hornblende and mica schist. 



As represented in the section, the beds all dip toward the north at 



