METEORITES OF NORTH AMERICA. 319 



County, Kentucky. The meteorite, which is a pallasite, has been known for some 35 years by the occupant of 

 the premises, where it served as a convenient stone on which to clean his boots after crossing the muddy fields. 

 Although recognized as of a peculiar type of stone, no suspicion of its meteoric nature was entertained, and it was only 

 when the zinc and lead mining excitement of 1902 caused a sample of it to be sent to Mr. E. O. Ulrich, of the United 

 States Geological Survey, with a request for information, that its true nature became known. It is through the influ- 

 ence of Mr. Ulrich that the specimen was obtained for the National Museum. 



Prolonged exposure has, naturally, brought about a great amount of oxidation to the exterior portion of the material. 

 More than that, the rough usage to which the exposed portion was subjected, and the breaking away of small masses 

 by the curious and the prospector, has so obscured the original form that little of value on this subject can be said. 

 The mass, as it came to the museum, is in the form of a rude prism some 55 cm. in height, with sides measuring 33 cm. 

 and 36 cm., respectively. Although badly oxidized, two of the sides show rough pittings. 



As stated above, the stone is a pallasite. It differs, however, from the usual pallasites in that, while those may 

 properly be described as spongy masses of iron containing silicate minerals, this is really a mass of silicate with a cement- 

 ing of iron, the proportion of iron, so far as can be determined from examination of the exterior of the mass, or of the 

 small pieces which have been broken away, being much less than in the case of the pallasite- of Kiowa County, Kansas. 

 From the Admire pallasite, described by the present writer in the Proceedings of the United States National Museum 

 for 1902, it differs in that the silicate (in this case olivine) occurs in large rounded blebs rather than in sharply 

 angular fragments. In this respect also it differs from the Eagle Station, Kentucky, pallasite. 



The mineral composition of this meteorite, so far as determined, has already been suggested. The main mass 

 of the material is of olivine in rounded blebs and in sizes varying from 5 to 25 mm. in diameter. These are quite 

 closely compacted, with the usual nickel-iron alloy in the interstices, and serving as a binding constituent, and in 

 smaller proportions the customary phosphide and sulphide. 



Although the meteorite has not yet been fully investigated, it is of interest in bearing out certain observations by 

 the writer in the case of the Admire, Kansas, meteorite, viz, the olivines are often shattered, with thin plates — mere 

 films or veinlets — of the phosphide extending up through them, as described in the paper already quoted. 



A slab will be sawn from the entire length of one side of the mass for the purpose of showing its internal structure 

 and securing material for study, the main mass being kept intact, after the usual custom of the museum. It is expected 

 that later more complete analyses will be made and a more detailed description given. 



The weight of the mass as received was 351 pounds (159.21 kgs.). It will be known aa the Mount Vernon meteorite. 



A later detailed account was given by Tassin, 2 as follows: 



The meteorite here described was found on the farm of Capt. S. T. Fruit, in Mount Vernon Township, about 7 

 miles northeast of Ilopkinsville, Christian County, Kentucky. Although known for some 35 years, its meteoric 

 origin was not suspected until 1902, and the first published account and preliminary description was given by Dr. 

 George P. Merrill, in the American Geologist in 1903. 



A cut surface shows the mass to be a pallasite of the Krasnojarsk type (Pk), consisting essentially of nickel iron 

 occurring in cohering spongiform or reticulated masses containing olivine and varying amounts of troilite, schreiber- 

 site, carbon, chromite, and lawrencite. 



The nickel-iron constituent comprises about one-third of the mass of the entire surface as cut, and serves as a 

 matrix in which are contained rounded blebs of olivine varying in size from 1 to 30 mm. in diameter. Dislodging the 

 olivine blebs will in general disclose a very thin, black, specular film more or less completely lining the entire cavity, 

 and which is rich in carbon and usually contains some chlorine as chloride, together with more or less sulphur as sul- 

 phide. Next to this is frequently found a more or less continuous layer of schreibersite or troilite, or both. These 

 in turn are followed by the nickel-iron constituent made up of kamacite, taenite, etc. 



The olivine blebs are quite commonly penetrated by cracks in all directions. These cracks may or may not be 

 filled with other substances. In the former case they are charged either with metallic iron, the black, specular 

 chlorine-containing material above referred to as commonly surrounding the olivine, and which often contains chro- 

 mite, with limonite (probably resulting from the oxidation of the specular substance), and which also contains 

 chromite, or, and this but rarely, with schreibersite or troilite. 



The mass contains, approximately, the following percentage composition, calculated from the results of several 

 analyses: 



Olivine 63. 15 



Nickel iron 33. 12 



Schreibersite 1. 95 



Troilite 69 



Chromite 1. 00 



Carbon 09 



Chlorine trace 



100.00 



