154 



Mr. X. Story-Maskelvne on the 



[Jan. 13, 



remains un combined in the form of erystallixed silica with the specific 

 gravity of a fused quartz, and that where magnesia and other bases are in 

 excess, a basic silicate wi:h the formula of olivine absorbs the supplementary 

 portion of these bases. Calcium, when present, would convert into augite 

 its equivalent ratio of what would otherwise constitute enstatite, and it is 

 possible that this is true even when this element is distributed in small 

 quantities throughout the mass. 



No alumina, and consequently no feldspathic ingredient, has been de- 

 tected in this meteorite. 



VIII. Composition of thr entire Meteorite. 

 With the view of determining the different ingredient minerals present 

 in the Bus:: i^e:e:r::e. -"ragmen's and dust from the neighbourhood of the 

 nodule of sulphide and augite were analyzed. The mineral was treated 

 with hydrogen chloride, carbon disulphide, and potash, which removed 

 16*873 per cent., leaving a residue of 83-127 per cent. ; the composition 

 of these two portions, soluble and insoluble, is given below : — 



In.?-: 1 -*:lf p«: rti : 

 J! 



Per- Oryg«i 

 outages. ratios. 



0891 



46357 24*727 



12-375 3-535 



23-266 9-299 

 0-14 

 0-455 

 0 019 



83-503 



The ratio of the silicic acid to the magnesia and lime in the latter 

 analysis corresponds with the composition (|Mg|Ca)0. SiO,. Regarding 

 the calcium of the white and grey varieties of enstatite to be present as 

 angite intercalated with the enstatite, we may assert that while all the 

 silicates of this meteorite present the typical formula MO, SiO„ three 

 equivalents of the rock near the nodule may be treated as composed of two 

 equivalents of augite and one of enstatite ; in other parts of the stone the 

 latter mineral predominates. 



A formula for the augite with magnesium and calcium in equal pro- 

 portions would no doubt more truly represent its composition ; it is, how- 

 ever, as impossible to separate the enstatite intercalated with it as it is to 

 remove this mineral when blended with the enstatite. 



IX. Solubility of the Minerals of the Bu*ti Meteorite. 

 As it appears of importance to determine the degree to which these 



S- If z<rzi:-. 

 I r r- Oxygen 



Calcium sulphate 0442 



Calcium sulphide. ... 4- 133 



Iron oxide 0194 



Silicic aeid 6*514 3 474 



Lime 0-022 0 006 



Magnesia 5 055 2 02 



Potash 0 099 



Soda 0118 



Lkhia 



16*577 



