THE IRON SERIES, CONTINUED. 119 



These analyses are mostly taken from State reports and from 

 Mineral Resources of the United States. They are intended to 

 illustrate the general run of compositions, but for Birmingham and 

 Marquette are high. Analyses vary widely. 



Amer. GeoL, III. 6. J. R. Gage, " On the Occurrence of Iron Ores in Mis- 

 souri," Trans. St. Louis Acad. Sci., 1873, Vol. III., p. 181. E. Harrison, 

 " Age of the Porphyry Hills," Ibid., Vol. II., p. 504. E. Haworth, " A Con- 

 tribution to the Archaean Geology of Missouri," Amer. GeoL, I. 280-363 ; 

 "Age and Origin of the Crystalline Rocks of Missouri, "Bull. F., Mo. Oeol. 

 Survey, 1891. A. V. Leonhard, "Notes on the Mineralogy of Missouri," 

 Trans. St. Louis Acad. Sci., Vol. IV., p. 440. F. L. Nasoa, "Report on 

 the Iron Ores of Missouii,'' Mo. GeoL Survey, II. Rec. R. Pumpelly, 

 " Geology of Pilot Knob and Vicinity," Mo. GeoL Survey, 1872, p. 5 ; see 

 also remarks on Iron Mountain, Bull. GeoL Soc. Amer., Vol. II., p. 220. 

 Rec. W. B. Potter, " The Iron Ore Regions of Missouri," Journal U. S. 

 Asso. Charcoal Iron Workers, Vol. VI., p. 23. Rec. F. A. Sampson, "A 

 Bibliography of the Geology of Missouri," Bull. II., Mo. GeoL Survey, 1890. 

 (This is a valuable book of reference.) F. Shepherd, Ann. Rep. Mo. GeoL 

 Survey, 1853-54. Hist. A. Schmidt, " Iron Ores of Missouri," Mo. GeoL 

 Survey , 1872, p. 45, and especially p. 94. Rec. J. D. Whitney, Metallic 

 Wealth of the U. S., p. 479 



