METEORITES OF NORTH AMERICA. 227 



Brezina 5 classed the iron as a brecciated hexahedrite and described it as follows : 



The surface is smoothed off by weathering, yet the interior is still fresh. The grains vary in size from extreme 

 fineness to 10 cm. in diameter. The individual grains under the glass, besides unitary Neumann lines running through 

 them, frequently show a fine granular composition. The double structure recurs also on a large scale, since blades 

 of rhabdite arranged in planes run undistorted through all the grains. On account of the interior binding together 

 of jagged, interlocking grains, the whole iron makes the impression of an immense kamacite lamella. In one part of 

 the iron occur grains of magnetite of the size of mustard seeds or hazelnuts. 



Cohen 6 described the structure and gave an analysis as follows: 



The structure varies so that on one end of the mass there is a fine-grained aggregate; then come large, isolated 

 grains, and finally unitary hexahedrites inlaid with small isolated grains. The smaller grains are as a rule rounded, 

 irregular, and of varied form; every part shows the same oriented luster. The Neumann lines and pittings are very 

 distinct. Under the microscope, many grains show a fine network of hair-like cracks, which must be regarded as a 

 sort of fracture phenomenon, since the luster remains peculiar. In others are found tiny dark inclusions; it is this, 

 doubtless, which constitutes the granular character mentioned by Brezina. Besides fine rhabdites there are also a 

 few large schreibersites surrounded with a small smooth etched zone. 



Analysis (Zaubitzer): 



Fe Ni Co Cu Cr S P C Residue 



93.06 5.35 1.00 .... 0.23 0.08 0.31 .... 0.08 =100.11 



The meteorite is distributed, the Vienna collection possessing the largest quantity, 2,157 

 grams. 



BIBLIOGRAPHY. 



1. 1887: Kunz. On some American meteorites. — 2: The Chattooga County, Georgia, meteorite. Amer. Journ. Sci., 



3d ser., vol. 34, pp. 471-472. (Illustrations; analysis by Whitfield.) 



2. 1889: Huntington. Proc. American Acad. Arts and Sci., vol. 24, p. 34. 



3. 1890: Fletcher. Mexican meteorites. Mineral Mag., vol. 9, p. 106. 



4. 1893: Meunier. Revision des fers m^teoriques, p. 76. 



5. 1895: Brezina. Wiener Sammlung, pp. 292-293. 



6. 1905: Cohen. Meteoritenkunde, Heft III, pp. 239-240. 



HOMESTEAD. 



Iowa County, Iowa. 



Here also Amana, Iowa County, Marengo, Sherlock, and West Liberty. 



Latitude 41° 45' N., longitude 91° 53' W. 



Stone. Brecciated gray chondrite (Cgb), of Brezina; Limerickite (type 38, subtype 2), of 



Meunier. 

 Fell 10.15 p. m., February 12, 1875; described 1875. 

 Weight, 210 kgs. (460 lbs.). 



The first scientific mention of this great meteoric fall seems to have been in the American 

 Journal of Science for May, 1875, ' where it is stated that a meteor fell in Iowa on the night of 

 February 12, with loud detonations. The principal portion of the fragments from the stone 

 are stated to have been secured for the Iowa State University by Professor Leonard. A pre- 

 liminary examination of the gases of the meteorite by Professor Wright 2 was reported in the 

 next (June) issue of the Journal as follows: 



By the courtesy of President Thacher, of the State University of Iowa, the writer has received some fragments 

 of this meteorite, an examination of which has yielded some very interesting results. The meteorite is of the stony 

 kind, containing numerous small grains of metallic iron, and not greatly differing in appearance from others of its 

 class. 



A quantity of the iron, having been separated, was found to contain several times its volume of gaseous sub- 

 stances, much of which it yielded on a very moderate elevation of temperature. The spectroscope plainly indicated 

 the predominance of carbon compounds, and an analysis showed that very nearly one-half of the gas was made up of 

 the two oxides of that element, the approximate percentages being C0 2 , 35; CO, 14; the two together, 49 per cent. 

 The residue consisted largely of hydrogen, but the exact proportion was not determined. These relations show a 

 marked difference between the iron and the stony meteorites as to their gaseous contents, as in the former the hydrogen 

 is most abundant, while in the latter the oxides of carbon are the characteristic constituents. 



The spectrum of the gases at a few millimeters pressure gave the carbon bands very brilliantly, the hydrogen 

 lines being comparatively weak and inconspicuous, though at a very low pressure they become relatively stronger. 

 The brightest carbon bands were the three in the green and blue, the red one being much feebler. Now these are 

 precisely the ones most conspicuous in the spectra of some of the comets, and this fact is a remarkable confirmation of 

 the received theory as to the meteoric character of these bodies. 



