332 J. £. Willet on Meteoric Iron from Georgia. 
of the larger bars; and the crystalline structure of the mass might 
be overlooked with the action of this acid alone. Nitric acid, 
however, brings out the Widmanstattian figures most beautifully. 
The etched surface is a perfect miniature copy of the Texan iron; 
the largest bars of the Putnam county iron corresponding with 
those of medium size in the Texas iron, and thence diminishing 
to bundles of striz hardly visible to the naked eye. The trian- 
les and parallelograms are proportionally small. Query: Are the 
crystalline figures of meteoric irons, in any degree, proportional 
to the meteoric masses? If so, may we not infer from the size 
of them, whether the iron be an entire mass, or a fragment of a 
large one? 
Neutral sulphate of copper produces no precipitate of metal on 
the iron; the slightest addition of acid causes the deposit of cop- 
per. Moreover, I find, that if the film of copper be wiped off as 
soon as formed, the sulphuric acid has etched out the figures su- 
perficially but very imperfectly. Liquid sulphuric acid, wher 
cold, has no effect upon the surface. ? 
In addition to the above description, I subjoin an interesting 
note from Prof. Shepard, containing an analysis of the 10n, 
which he has very kindly furnished at my request. 
“ Charleston, 8. C., February 10, 1854. 
My Dear Sir—In comparing the Putnam county meteoric iron with 
specimens from other localities, I notice a striking similarity 10 its 
structure to that of the Texan mass. Like it, your iron is compact, 
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into beads ortknobs. The pyrites in my specimens is scarcely | 
recognized, except in one or two very limited patches, which are irreg- 
ular and vein-like. : ‘ 
The iron appears to have suffered a very remarkable disintegrai 
to the depth of half an inch or more below the thick, scaly crust wil 
which the mass was coated; in consequence of which it cleaves be 
regularly, like the Cocke county, Tennessee iron, into tetrahedral 
rhomboidal fragments. 
The specific gravity of the fresh internal portions of the 
769. A single analysis gave me the following result: 
Tron, é ‘ ‘ 3 ‘ é < 89°52 
Nickel, with traces of cobait, - - + - 982 
Tin, phosphorus, sulphur, m gnesium and calcium, 1-66 
——— 
100-00 
mass is 
Very truly, yours aaa 
a Cuances Uran SaEPan: — 
