MEMOIR ON METEORITES. 291 



meteoric origin not falling properly under either of the above 

 three heads, still they will be seen upon close investigation not 

 to interfere in any way with the general conclusions that are 

 attempted to be arrived at; for these constituents are repre- 

 sented in the stony materials of the second class, from which 

 their only essential difference consists in the absence of metallic 

 particles. 



If we now examine chemically the three classes mentioned, 

 we find them all possessed of certain common characteristics 

 that link them together, and at the same time separate them 

 from everything terrestrial. Take first the metallic masses; 

 and in very many instances, in some fissure or cavity exposed 

 by sawing or otherwise, stony materials will frequently be 

 found, and a stony crystal is sometimes exposed ;* now examine 

 the composition of these, and then compare the results with 

 what may be known of the stony meteorites, and in every 

 instance it will agree with some mineral or minerals found in 

 this latter class, as olivine or pyroxene — most commonly the 

 former; but in no instance is it a mineral not found in the 

 stony meteorites. If these last in their turn be examined, dif- 

 fering vastly in their appearance from the metallic meteorites, 

 they will with but two or three exceptions be found to contain 

 a malleable metal identical in comj^osition with the metal con- 

 stituting the metallic meteorites. 



As to those mixed meteorites in which the metallic and 

 stony portions seem to be equally distributed; their two ele- 

 ments are but representatives of the two classes just described. 

 Examined in this way, there will be no difficulty in tracing the 

 same signature on them all, indorsing the above as their true 

 character, and almost serving to tell us whence they came. 

 They may emphatically be said to have been linked in their 

 origin by a chain of iron. 



There is one mineral which there is every reason to believe 

 constantly accompanies the metallic portions, and which may 

 be regarded as a most peculiar mark of difference between 

 meteorites and terrestrial bodies. It is the mineral screibersite 

 (see first part of this memoir), to which the constant presence 

 of phosphorus in meteoric iron is due. This mineral, as already 

 remarked, has no parallel on the face of the globe, whether we 

 consider its specific or generic character, there being no such 



