306 TRANSACTIONS OF THE CANADIAN INSTITUTE. [YOL. II- 



I mile wide, and 30 miles long. The Montreal River (which is the 

 boundary between the State of Wisconsin and the upper Peninsula of 

 Michigan) flowing northward into the lake, cuts through the range nearly 

 midway between the extremes of the present exploitations, about one 

 half of the ore strike, as now believed to be determined, lying in Ontona- 

 gon County, Michigan, and the other half in Ashland County, Wisconsin., 



There seems good reason to believe that the ores lie in lenses of greater 

 or less width and depth, throughout an ore bearing stratum, confined by 

 quartzite, which is very regular, and diorite, which in places is decom- 

 posed into so-called "soap rock." In places small quantities of Kaolin 

 is found formed from the decomposed felspar in the diorite. The dip 

 of the ore bearing rocks is 65° to 70°. Most of the analyses of the Iron 

 ores show that they are rich in metallic Iron, from 50 to 66 per cent., 

 very low in Phosphorus, variable in Silica and free from sulphur. The 

 Colby mine as an example shows metallic Iron from 48 to 65^ ; Phos- 

 phorus '04 to 'OS^ ; Silica, 2 to 8^ ; and Mn. i to 1 1/^ ; analyses from a 

 number of other mines show, Fe. 51 to 65%; P. "02 to "08%; Si. 3 to 5^;, 

 and a little Mn. in some ores. 



This range was only opened in 1885, and the results have been simply 

 prodigious. From a wilderness a very few years ago, it has by means of 

 railroad communication, been opened into a thriving populous district. 

 Several railroad systems now run into this range, which has outstripped 

 the older ranges. 



As an example of the ore deposits I might mention the " Ashland Mine" 

 which I visited. The strike is N. 80* E. Dip of foot wall 65° N. On 

 the property there are 4 lenses of ore dipping to the North and pitching tO' 

 the East. The width of ore is 220 to 240 feet in widest part. The usual 

 manner of working in this district, as I saw it in this mine, is by running 

 a slope down the quartzite foot wall and running levels from it. 



The footwall is quartzite, into which they ran 68 feet, below that is 

 bluish argillite, and below that to the south is granite. Diorite, varying 

 to crystaline hornblendic rock, is seen on the hanging wall ; and next to 

 that come mixed ore and quartzite, then alternating bands of diorite 

 mixed ore and quartzite. 



Nevada style of timbering is used and there are 3 million of feet of 

 timbering in this mine. As an example, the first room is 140 feet wide by 

 60 feet high and 70 feet long, and this space is all built up with timber. 



The ore is an open hematite in layers with cavities, looking very much 

 as if it was for the most part the result of a secondary formation ; some 

 of it is hard steel blue ore. At the" Germania Mine" in the same range,. 



