METEORITES OF NORTH AMERICA. 439 



In the examination made by M. Berthier he failed to detect the presence of cobalt, but it is mentioned by Professor 

 Clark that Manross had found it in a specimen from the cabinet of Professor Wohler; my examination confirms that of 

 Mr. Manross. 



To the kindness of W. S. Vaux, Esq., I am indebted for the material for this investigation; Mr. Vaux has in his 

 magnificent cabinet the principal portion of a mass which weighed over 10 pounds. It was originally about 6 inches 

 long, with an average diameter of 3 inches; the lump was oblong with rounded ends, the whole being covered with a 

 thin crust of limonite. 



A cross section cut from this lump has been carefully polished and etched by strong nitric acid, which gives a most 

 beautiful surface of about 3.5 inches in length by 2.5 in breadth, covered with the greatest complexity of Widmann- 

 statten figures which almost defy description. 



The surface is crossed by bands about one-tenth to one-sixteenth of an inch in breadth; these apparent bands are 

 cross sections of different planes, as is readily perceived by their different refractive powers. 



On changing the position of the specimen, those that are a bright silvery white in one direction become a dull gray 

 in another, and vice versa. 



There are several systems of bands which preserve a parallelism among themselves and cross other systems at 

 various angles, forming trapezoids, rhombs, and triangles. These several fields and their characteristic etchings will 

 be described in detail at some future time. Along the bands or planes thin laminae of schreibersite have been observed, 

 as in other meteoric irons. 



Embedded in one side of the large lump (just described) was a globule of pyrrhotine which looks as if it had been 

 dropped into the iron when it was in a semifluid state. This globule appears to have been about an inch in diameter; 

 it was in part decomposed, but a small portion of the mineral was separated sufficiently pure for the determination of 

 its specific gravity and analysis. On dissolving it in hydrochloric acid thin laminae of schreibersite separated with 

 minute portions of chromic iron. 



Through the kindness of Dr. F. A. Genth I have been permitted to make the following analysis in his laboratory: 



No. 1. Pyrrhotine dissolved in nitric acid gave — 



Sulphur 33.76 



Iron 57.95 



Nickel 6.70 



Cobalt 56 



Silicon 05 



Phosphorus 25 



99.27 

 No. 2 dissolved in hydrochloric acid gave — 



Iron 58. 25 per cent. 



A residue remained which dissolved after being treated with hydrochloric acid and chlorate of potash consisted of — 



Copper 0. 12 per cent. 



The remainder consisted principally of chromic iron with a small portion of schreibersite. 



The specific gravity was found to be 4.822. 



The ratio of sulphur to the metals was found to be— 



Sulphur 2.102 Iron 2. 0661 „ 



Nickel and cobalt 0. 245.T' 



It will be seen that the composition corresponds with that of pyrrhotine, considering its formula to be FeS.if we 

 disregard the few impurities which were found with it. 



The meteoric iron was first treated in a flask with hydrochloric acid and the gas evolved was passed through a solu- 

 tion of ammonia chloride of copper, but not a trace of sulphur could be detected in this manner. 



In the fifth supplement to Rammelsberg's Handworterbuch der chemischen Mineralogie, this meteoric iron is 

 mentioned as passive, experiments having been made by Professor Wohler; but the piece belonging to Mr. Vaux is 

 evidently active, throwing down metallic copper from a neutral solution of its Bulphate. This experiment was repeated 

 with great care with confirmatory results. 



No. 1 was dissolved in hydrochloric acid, and a slight precipitate was obtained by hydrosulphuric acid, which, on a 

 careful examination before the blowpipe, was found to be copper with a trace of tin. 



Iron 90. 72 



Nickel 8. 49 



Cobalt 44 



Schreibersite, chromic iron, etc 38 



Silicon 25 



Phosphorus 18 



100.46 

 The phosphorus was estimated in a separate portion which was first oxidized by nitric acid and fused in a plati- 

 num crucible with carbonate of soda. 



