THE 



AMERICAN 



JOURNAL OF SCIENCE, &c. 



Art. I. — Analysis of the Meteoric Iron of Louisiana, and 

 discovery of the Stanniferous Columbite in Massachusetts ; 

 by Charles Upham Shepard, Assistant to the Professor 

 of Chemistry, Mineralogy, ^c. in Yale College. 



The circumstances relating to the occurrence and natural 

 properties of the Louisiana iron, as well as the detection of 

 nickel in its composition by Prof. Silliman, have, for several 

 years, been before the public;* but no extended examination 

 with a view to determine the presence or absence of other 

 metals, or to ascertain the relative proportions of the iron 

 and nickel, so far as I am informed, has hitherto been at- 

 tempted. Having been permitted to detach a few fragments 

 from the fine specimen of this iron, belonging to the Cabinet 

 of Yale College, I engaged in the following examination.! 



1. Upon a fragment of thQ meteoric iron, was poured ni- 

 tro-muriatic acid. Its entire solution was effected without 

 the aid of heat, and the liquid assumed a reddish brown color. 



2. To a part of the solution, was added muriate of ba- 

 rytes ; no precipitate took place, from which the absence of 

 sulphur was inferred. 



3. The remainder of (1.) was decomposed by ammonia in 

 excess; and the liquid after being warmed for a few moments 



* See Vol. VIII, p. 218 of this Journal. 



t The mean specific gravity of three specimens, whose greatest difference was 

 one tenth of a grain, was 7-543. This result differs slightly from that obtained 

 by Dr. Bruce, who places it at 7-400. A want of perfect agreement in differ- 

 ent trials may be expected, however, notwithstanding the homogenity of the 

 mass; since the fragments examined, will rarely possess the same density, 

 owing to the different degrees of mechanical forCe applied, to effect their sepa- 

 ration. 



Vol. XVL— No. 2. 1 



