Meteoric Stone which fell at the Mission Station of St. Mark's. 15 



cent. Two other carbon determinations, made with black chondritic 

 meteorites for the sake of comparison, gave, in the case of the 

 MacKinney meteorite, 0-13, and in the case of the Farmington, 

 0-12 per cent, of carbon. These two figures are so low that one can 

 draw no certain conclusion from them of the presence of a carbon 

 or a carbon compound, while this should be the case with the St. 

 Mark's stone. 



5. The solution obtained by boiling with water contained, besides 

 a small quantity of silica (0-07 per cent.) — 



Ca = 0-28 

 CI = 0-27 

 S = 0-08 



One can therefore assume the presence of some calcium chloride 

 (0-42 per cent.) and calcium sulphide (oldhamite) (0-18 per cent.) ; 

 the latter was shown by Borgstrom to occur also in the Hvittis chon- 

 dritic meteorite. From the data thus obtained there results the 

 chemical composition given below under 6, and the mineralogical 

 composition ■'■ given under 7 ; in this, however, the nature of the 

 silicates soluble in hydrochloric acid must, for the time being, be left 

 undecided. 



7. 



Enstatitef 45-96 



Other silicates 19-45 



Nickel iron 19-27 



Troilite 14-05 



Schreibersite 0-32 



Oldhamite 0*18 



Calcium chloride 0-41 



Carbon 0-36 



100-00 



101-15 



* As the result of the complete investigation, St. Mark's is a black, carbonaceous 

 quartz and plagioclase bearing enstatitic chondritic meteorite. — C. K. 

 f Without regard to possible contained alkalies. 



