270 MEMOIRS NATIONAL ACADEMY OF SCIENCES, VOL. XIII. 



not afford shaving. There were a few dots of an earthy mineral or rock, having a magnesian base, closely adhering 

 to fragments of pyrites. 



A fragment was analyzed by Hayes with the following result : 



Fe Ni FeS 2 CI Loss 



83.572 12.665 2.395 0.907 .461 =100 



It is thus seen that Hayes' analysis, while showing a high content of nickel, does not exhibit the 

 percentages obtained by Jackson. Hayes' account indicates that his specimen was a com- 

 plete individual and not a fragment from the original specimen. One must conclude, there- 

 fore, that either his or Jackson's analysis was faulty or that they worked on different meteorites. 



Partsch 2 examined a small piece of the meteorite sent him by Jackson and found it not 

 attacked by dilute nitric acid. After strong etching with concentrated nitric acid, the iron 

 showed neither Widmanstatten figures, lines, streaks, or bands. A polished surface showed 

 but little luster, was grayish black in color and exhibited grains, lines, and points of iron sul- 

 phide in so large quantity and uniform distribution as to differ from any iron that he had pre- 

 viously examined. 



Meunier, 4 in 1884, united the iron with that of Tucson, the characters of the group being 

 "compact, taking a good polish, and inclosing very small stony grains." In 1893, 5 he changed 

 the classification of Lime Creek to the braunite group and described the specimen as follows: 



In the Paris Museum there is a specimen of this iron with the following label, in Jackson's own handwriting: 

 "Meteoric iron in which I originally discovered chlorine combined with nickel and iron, in 1834." The metal is not 

 very compact, filled with small cavities which contain a black substance. A few bright grains resembling schrei- 

 bersite may be seen with the glass. 



Cohen 6 described the structure of the iron as follows: 



The iron acquires, upon etching, a glossy luster such as is characteristic of nickel-rich ataxites and especially 

 resembles Morradal. To the naked eye the surface appears somewhat speckled, but under the microscope these bound- 

 aries disappear entirely and the appearance is that of a homogeneous compact iron. When very highly magnified, 

 dark rods and points about 0.001 mm. in cross section appear in great numbers, giving the appearance of a netted struc- 

 ture of extraordinary fineness. These are, however, not uniformly distributed and disappear on some regularly- 

 arranged elongated areas 0.01 mm. in breadth. The latter appear clear, lending a hackly appearance to the surface, 

 and may well be the cause of the previously mentioned speckled appearance. The minute size of the inclusions makes 

 a study of the structure and description of it difficult. Besides some large 6chreibersites there are pretty uniformly 

 distributed a considerable number of little rods, grains, and spindles, all surrounded by a small, dull zone face of dark 

 grains. These would seem to be iron-nickel phosphide also. They sink on the one hand to microscopic dimensions 

 and on the other reach at times a length of 0.75 mm. To their falling out may perhaps be ascribed the depressions 

 seen on an etched surface. 



A fragment of the iron weighing 0.3 gr. was analyzed by Dr. Knauer, with the following 

 result: I, analysis; la, the analysis calculated to 100 after discarding residue and iron-nickel 



phosphide: 



Fe Ni Co P Residue 



1 65. 03 29. 99 1. 48 0. 19 0. 20 = 96. 89 



la 67.41 31.06 1.53 =100.00 



Tests for metals of the hydrogen sulphide gave no result, and the residue gave no reaction 

 for chromium. The above analysis supports Jackson's results. 



As Cohen remarks, most of the specimens labeled "Lime Creek" in collections will be 

 found to be Walker County. Such as are truly from the iron described by Jackson can be 

 known by their lack of hexahedral characters and by their high content of nickel. 



BIBLIOGRAPHY. 



1. 1838: Jackson. Chemical analysis of meteoric iron from Claiborne, Clarke County, Alabama. Amer. Journ.Sci., 



1st ser., vol. 34, pp. 332-337. 



2. 1843: Partsch. Meteoriten, pp. 133-134. 



3. 1845: Jackson. 1. Remarks on the Alabama meteoric iron, with a chemical analysis of the drops of green liquid 



which exude from it. 2. Letter from Mr. A. A. Hayes on the same subject, with remarks on the origin of the 

 chlorine found in the Alabama iron, and a description of new methods employed in the analysis of meteoric irons. 

 Amer. Journ. Sci., 1st ser., vol. 48, pp. 145-156. (Analysis by Uayes.) 



4. 1884: Meunier. M6teorites, pp. 35, 94, and 134. 



5. 1893: Meunier. Revision desfers m£teoriques, pp. 15 and 19. 



6. 1905: Cohen. Meteoritenkunde, Heft 3, pp. 128-132. 





