LAKAMIE HILLS. 15 



The mountain rises about 600 feet above the stream-bed, is irregular in 

 form, but has a somewhat oval-shaped outline. It occurs intercalated in the 

 granite, standing nearly vertical, with the walls in places sharply defined; 

 this is the case in the canon, where the dark iron body resembles a broad 

 dike, which rises to the top of the canon-wall. Frequently large masses of 

 granite are nearly encased in the iron, and again the iron body puts out 

 into the surrounding granite. The main deposit of iron is nearly a quarter 

 of a mile in length, with a strike a little to the west of north and east of 

 south. To the north the main deposit terminates somewhat abruptly; but 

 southward it crosses the canon, and may be traced cropping out through 

 the granitoid rocks with the same general strike for nearly 2 miles, in the 

 direction of Pebble Creek. These outcrops vary much in size, mostly mere 

 narrow seams, and small irregular patches of iron, which disappear in the 

 surrounding granite. Still fartlier. to the south, just above Horse Creek, 

 considerable deposits again make their appearance, but much smaller than 

 Iron Mountain, and, like the latter, have been held for valuable mineral 

 .bodies ; they are probably only a continuation of the larger one. The 

 ilmenite occurs chiefly as a compact massive deposit, iron-black in color, 

 with a submetallic lustre. It is frequently found, however, with a coarse 

 granular structure. It is accompanied by small amounts of magnetite and 

 hematite, which decompose and give portions of the mass a brownish-red 

 appearance. Prof. 0. D. Allen, of Yale College, examined specimens of the 

 Iron Mountain ore, and found it to contain a mixture of ferrous and ferric 

 oxide, which gave 50.83 per cent, of metallic iron, combined with 23.32 per 

 cent, of titanic acid. Other samples of the ore, analyzed by Professor Rich- 

 ards, of the Institute of Technology in Boston, gave the following results: 



Ferrous oxide 24.55 



Ferric oxide 48.97 



Titanic acid 23.18 



Sulphur 0.03 



Residue insoluble in acid 2.15 



98.88 

 Metallic iron 53.33 ' 



