Analysis of Meteoric Iron from Tennessee. 357 



addition of water brought flocks of silicic acid into view. The 

 results of this analysis give 



Iron, 93.80 



Nickel, 466 



Carbon, C i -^u • c • ^ 



Silicon ) ^1°"§ Z §T^f °^ ^'"°" { 0.10 



■nu 1 y and nickel alloy, i 



Phosphorus, { 3 



Oxygen, sulphate of iron, sulphur, > j ., 



moisture and loss, 5 



100.00 



Charleston, February 9, 1842. 



Since my return to New Haven, I have paid some attention to 

 another specimen of meteoric iron from the same mass with the 

 above, and which was kindly afforded me by Dr. Troost. On 

 breaking it to obtain a fresh fracture, the regular crystalline struc- 

 ture showed itself on the largest scale. The clean surfaces were 

 intersected by layers of brilliant magnetic iron-pyrites, varying 

 in thickness from one sixteenth to one fourth of an inch, whereby 

 a series of trihedral and rhombohedral areas of various sizes were 

 produced. These regularly inclosed spaces were mostly black, 

 from the diffusion of a sooty form of carbon between the plates 

 of the meteoric iron. The contrast between the areas and the 

 separating layers of pyrites was consequently rendered more stri- 

 king. Besides the distribution of the pyrites in plates or veins, 

 it also occurs in balls and almond-shaped masses, sometimes half 

 an inch or more, in thickness. The structure of these is concen- 

 trically laminar, the laminee being often separated by iron and 

 carbon. The pyrites forms nearly one sixth of the mass. Dr. 

 Troost presented me also with several loose balls of the shape of 

 the pyrites masses, which to the eye seem composed of little else 

 than carbon, concerning which a few remarks will presently be 

 subjoined. None of these balls are found imbedded in the speci- 

 men I am more particularly describing. 



If we except the bright projecting edges of the pyritic veins, 

 the Widmanst'dttian figures produced by etching with dilute 

 nitric acid on polished surfaces in directions of cleavage in this 

 iron, are by no means striking. Little channels and waving strise, 

 bright at bottom and dull at top, are indeed brought into view ,• 

 but these are so minute and irregular as to require the use of 



