File:The American Museum journal (c1900-(1918)) (18159905965).jpg

Title: The American Museum journal
Identifier: americanmuseumjo09amer (find matches)
Year: c1900-(1918) (c190s)
Authors: American Museum of Natural History
Subjects: Natural history
Publisher: New York : American Museum of Natural History
Contributing Library: American Museum of Natural History Library
Digitizing Sponsor: Biodiversity Heritage Library

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242 THE AMERICAN MUSEUM JOURXAL pronounced and somewhat more elongated in the round edge shown in Figure 3. The flat side shown in Figure 1 has comparatively few round piezoglyphs, but it has many pits, grooves and points due to the flowing of the melting surface of the mass during flight through the atmosphere. The almost square edge, which is illustrated in Figure 4 and which is considered to be an abrupt fracture occurring when the meteorite was near the end of its atmospheric flight, has an oxidized skin like the rest of the mass but shows piezoglyphs very imperfectly. Figure 1 shows the side which was in front during most of the meteor- ite's atmospheric flight and is called l)y the (xermans the "brustseite." The position of the furrows indicates that the line of flight was toward the upper right hand quarter of the mass as shown in this picture. Although the iron is unusually uniform and dense in structure, as will be brought out under the discussion of its composition, it evidently yielded unequally to the heat produced l)y friction with the atmosphere, and the air in passing over its surface plowed deep furrows ending in sul^conical pits and left sharp projections pointing forward in the direction of flight. A piece of the iron which had been sawed from the small entl of the mass was polished and etched with dilute nitric acid at the Museum and was afterwards polished again and treated with dilute and strong nitric acid and picric acid in succession by the chemists, Booth, Garrett and Blair, Philadelphia, picric acid proving to be the best mordant. The surface does not show the Widmanstatten lines usually characteristic of meteoritic iron, but instead it possesses an extremely fine granular crystalline structure, which is shown magnified 100 diam- eters in Figure 5 from a photomicro- graph made by the analysts. The iiomogeneous character of the mass and the paucity of nonmetallic contents are indicated by the high specific gravity. The chemical analysis, made by Booth, Garrett and Blair, resulted as follows:
Text Appearing After Image:
FIG. 5. GUFFEY METEORITE. PHOTO- MICROGRAPH. Polished .section nuignified KM) diam- eters to show c;yptoc;ystal- Hne structure.

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