295 



Per oxide of iron - =58.72=metallic iron, 41,12 



Silica - - - 34.48 



Alumina - - - 2.40 



Magnesia - - 0.39 



Sulphur (bj difference) 4.01 



100.00 



Search was made for nickel, copper, and chrome, but no trace 

 of those metals was discovered. The proportions of iron and of 

 silica were not different from those of meteoric stones, but per- 

 haps the perfect oxidation and combination of the iron with the 

 nitric acid was the strongest evidence of its terrestrial origin that 

 the specimen presents ; for even had nickel been discovered in 

 it, this would not alone prove its celestial origin, since the copper 

 ores worked at Point Shirley often contain nickel, which would 

 be likely to be found in some of the slags. 



Mr. Edwin Harrison, of Cambridge, reported the result 

 of an analysis of two specimens of Magnetite, the first 

 from the Iron Mountain, the second from the Pilot Knob, 

 Missouri. 



IRON MOUNTAIN ORE. 



Iron 68.95 



Oxygen 27.00 



Sand and Silic. of Alum. - - - - 3.07 



Manganese ------ (trace) 



Spec, grav., 3.997 at 13.°1 centigr. 



99.02 



PILOT KNOB ORE. 



Iron - 54.307 



Oxygen ------ 26.720 



Insol. subs, in H. CI. - - - - 17.509 



Spec, grav., 3.137 at ll.°5 centigr. 



98.536 



