GEOLOGICAL EXPLOKATIONS AND LITEKATURE. 89 



The inotst eastern section \vlii(tli may he fairly eonsidered as opeu is locally known 

 as the Sunday lake district, liavins' Wakefield, Michigan, ;is its business center. Here 

 several mines, notably the Brotherton. Sunday lake, and Iron (ihief, slnii])ed in the 

 aggregate about ol,(t(M» tuns otoic in ISSi; (Vuni nnderiiround workings, and as in tliis 

 vicinity the ridge is less detlned and the gr<»und at a lowei- lc\ el, tlie exploitation has 

 been more expensive and difficult and the pi'ogress less niaiUcd than elsewhei'c. The 

 ore bearing rocks api)arently strike through Sunday lake. Following west .'i miles 

 the Black river cuts through the ridge, and tlic ore has been ibniid in tills gap. 

 Three miles still farther, the highest elevati(ni of the I'idge is found (reported as 1,100 

 feet above lake Superior or 1,70(1 feet above tide) at the Oolbj' mine, which overlooks 

 the town of Bessemer, Micliigan, built on the northern slojie of the ridge. Just west 

 of the Colby mine the stiike of tlie ore-bearing rocks ciosses a \alley about half a 

 mile wide, and then follows the ridge for about .5 miles to wliere the main brandi of 

 the Montreal river cuts tlirongh it, and in the westein half of this section are found 

 three mines, the Aurora, tlie Norrie, and the Ashland, whi<-h, next to tlie <'olby, have 

 been the principal ]>rodiicers. and whose aggregate output for the year ISSG was 

 about. '520, (too tons. In addition othei's of smaller capacity aie o]>erated. After rising 

 from the valley of tlie Montreal river into Wisconsin the oic mines are <iii elevated 

 ground for about 3 miles, in which there are several producers. 



After crossing the west branch of the iMontreal river there are few more judduc- 

 ing mines, but ex]>loitation has lieeii carried beyond this stream for .3 miles, and 

 farther west large syndicates own land on which prosi)ecting is fairly active. 



Tlie ("olby mine, the i)est known and largest (levelo])cd working in the Gogebic 

 iron iiinge, is at present operated under a lease which has less than two years to run. 

 The time limit has undoubtedly encouraged the large outputs of S4..'?0L' tons in ISSo, 

 the first year of actual working, and li4.S,.S10 tons in 188(». The mine, being located at 

 the most elevated jioint in the legion, is reached by a switch-ba<'k railway connection 

 which formerly ran diicctly into the open workings, and the ore was dug and loaded 

 onto the cars which carried it to A.shland for shipiiing. Whih? the open ])itwork of the 

 Colby and Aurora mines are the features of the (rogebic region, the dcjiosit as found 

 in the Noirie and ^Vshland mines indicates what may be considered as specially good 

 mines, and if one-half of those already oiierating can reach the output of these the 

 district will be an enormous producer. As undergionnd workings must e\eiilually 

 be generally adopted, the operations of these two mines will i)rove a guide as to the 

 future ]iossibilities ot'others according to the width of the ore bodies. In them are also 

 found the '• horses '" which add to the uncertainty of the niiniiig <'nteii)rises. 



Most of tlie mines that were on the shijijiing list in ISSd have been sinking 

 and opening up ground for the season's work. No large de|)osits have been found 

 during winter development except possibly at the Anvil and I'yan. A great many ex- 

 plorations are being carried (ui, but the most productive portion of the range seems 



