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Field Columbian Museum — Geology, Vol. I. 



sion of a network in which grains of kamacite are imbedded. The 

 contour of the figures is for the most part curved and wavy, especially 

 near the borders of the section. The most reasonable explanation 

 for this seems to be the treatment probably given the mass by the 

 ancient workmen. If heated until it became somewhat plastic and 

 then hammered, just such curving of the plates might be pro- 

 duced. Owing to the distortion of the figures it is impossible to 

 positively classify the iron. Apparently it is an octahedral iron hav- 

 ing lamellae of medium width. While two alloys, kamacite and taen- 

 ite, are plainly discernible, no troilite or schreibersite can be seen, 



Fig. 6. Etched surface of Hopewell Mounds meteorite showing Widmanstatten figures curved 



and interwoven, probably on account of heating and hammering that 



the mass has received. X 8. 



although the presence of the two latter is indicated by the percent- 

 ages of sulphur and phosphorus found on analysis. At one end of 

 the mass are three large irregular pores such as might have been pro- 

 duced by the falling out of crystals of chrysolite or other stony mat- 

 ter. There is no other evidence, however, that such stony matter 

 was at one time present and the cavities may have been produced in 

 a purely mechanical way. This seems rather the more probable from 

 the fact that the rest of the mass is quite compact. The iron is rather 

 soft, cutting easily with a hack-saw, and malleable. It is active to 

 copper sulphate. 



For purposes of quantitative analysis a small piece was sawed 

 from one end of the mass and cleaned from rust by filing and scraping. 



