MUSEUM OF COMPARATIVE ZOOLOGY. 3 



hundred feet, have been completely shattered or broken into minute 

 fragments, which, having retained their original position, were again 

 cemented by the injection of calcareons matter. This injection has 

 filled the most minute fissures, and so perfect is it, that, in looking upon 

 the face of a mural cliff of these rocks, the veins may be easily seen at 

 a distance of many i-ods, forming, as it were, a complete net-work over 

 the cliff, and so minute is it, that a single hand specimen frequently 

 contains many hundreds of these veins." {I. c, p. 492.) 



In this Report is the first mention of iron ore in this district that we 

 have seen. He gives amongst the minerals of the " Metamorphic group 

 of Rocks," ** scaly red oxide of iron" and " hscmatite." Regarding the 

 latter he says: "Although the htematite is abundantly disseminated 

 through all the rocks of the metamorphic group, it does not appear in 

 sufficient quantity, at any one point that has been examined, to be of 

 practical importance." (/. c, p. 504.) 



In Dr. Houghton's Fifth Report some remarks were made both 

 upon this district and upon the copper district, but nothing of special 

 importance w^as added.* Mr. George N. Sanders, in a report to the 

 Ordnance Office,t speaks of collecting " rich specimens of iron ore " on 

 the Menomonee River, In the same documents for 1845 - 46 ;}: are given 

 reports for the year 1845, by William A. Burt and Bela Hubbard. § Mi\ 

 Hubbard evidently considered that the ridges in the Marquette Iron 

 District were composed in the centre of eruptive rocks, but not outcrop- 

 ping, being "capped as well as flanked by the metamorphosed rocks.' 

 He states in regard to the metamorphic rocks that "these rocks are 

 throughout pervaded by the argillaceous red and micaceous oxydes of 

 iron, sometimes intimately disseminated, and sometimes in beds or 

 veins. These are frequently of so great extent as almost to entitle them 

 to be considered as rocks. The largest extent of iron ore noticed is in 

 township 47 north, range 26 west, near the corners of sections 29, 30, 31, 

 32. There are here, too, large beds or hills of ore, made, up almost entirely 

 of granulated, magnetic^ and specular iron, with small quantities of spa- 

 those and micaceous iron. The more northerly of these hills extends in 

 a direction nearly east and west, for at least one fourth of a mile, and 



* Joint Documents, Michigan, IS 42, pp. 436-441. 



t Senate Documents, 28th Cong. 2(1 Sess., 1844-45, XI., Doc. 175, p. 11. 



} 29th Cong. 1st Sess., VII., Doc. 357. 



§ See also Senate Documents, 1849-50, 31st Cong. 1st Sess., III. 802-842, and 

 The Mineral Region of Lake Superior, by J. Houghton and T. W. Bristol, (Detroit, 

 1846,) pp. 3-39. 



