MINERAL CONSTITUENTS OF METEORITES. 
207 
silicate with the formula of olivine absorbed the supplementary portion of these bases. 
Where calcium is present, it probably converts into an augite a portion of the materials 
that otherwise would go to constitute enstatite. 
In none of the particular meteorites hitherto examined in the Museum Laboratory 
has a trace of alumina been found, though it has been carefully looked for, and conse- 
quently no felspathic ingredient has been detected in them. 
VIII. General Analysis of the Basti Meteorite. 
In order to determine approximately the proportions in which the different ingredient 
minerals were present in the meteorite, and to ascertain whether any other mineral had 
escaped detection, an analysis of the fragments and dust of the stone from the neigh- 
bourhood of the nodule containing the sulphides and the augite was made. The mate- 
rial employed was that obtained on cutting the meteorite by a dry wlieel-saw, used to 
prevent the introduction of foreign substances. 1*874 grm. were taken for analysis. 
The sulphur was determined, as in the case of the Oldhamite, as sulphide of silver, and 
as separated by means of carbon disulphide. Heated with hydrogen chloride, and 
afterwards with potash, there was dissolved by those reagents . and by the carbon 
disulphide 16*873 per cent., 
the residue being 83*127 
100*000 
The soluble part gave the results in column I., the insoluble part those in column II. ; 
the sulphur and sulphuric acid being supposed to be present as calcium sulphide and 
sulphate respectively. 
I. 
Calcium sulphate . . . 
Calcium monosulphide . . 
0-442 
4-133 
II. 
Iron oxide 
0-194 
Oxygen ratios. 
0-891 
Oxygen ratios. 
Silicic acid ..... 
6-514 
3-474 
46-357 
24-727 
Lime 
0-022 
0-006 b 
12-375 
3-535 h 
Magnesia 
5-055 
2-02 1 
0-017 > " 073 
23-266 
9-299 
Potash 
0-099 
0-14 
0-023 > 
Soda 
0-118 
0-03 j 
— 
0-455 
0-117 | 
Lithia 
16-577 
0-019 
83-503 
0-01 J 
The insoluble part in this analysis would correspond to a composition Si O , (Mg* Cap), 
which, if we consider the calcium as being present as a constituent of the augite and 
the formula of this mineral to be Si 0 3 (Mg| Ca*), will give for the insoluble silicate 
of the rock in the neighbourhood of the nodule a composition of two equivalents of 
augite to one of enstatite. As the analysis of the soluble portion showed that some of 
the above minerals had been dissolved, it was thought advisable to determine what and 
how much of them were rendered soluble by the action of hydrogen chloride in the cold, 
hor this purpose some fresh material, selected partly from the neighbourhood of the 
2 e 2 
