54 RECORDS OF THE AUSTRALIAN MUSEUM. 



chloride of mercuiy in the cold, the sulphide of iron being unacted 

 upon under these circumstances. The latter method of purification 

 was chosen. '18 gram of iron was extracted from "52 gram of 

 the original powdered sulphide by allowing the latter to stand 

 for twenty-four hours with a concentrated solution of mercuric 

 chloride in the cold. This is equal to 34*6 per cent. 



The purified troilite had a specific gravity of 4'645 (uncorr.), and 

 an analysis of "2408 gram, gave : — 



Residue trace. 



Iron 62-01 



Nickel and Cobalt -89 



Sulphur 38-28 



101-38 



From the analysis of the iron it will be noticed that the quantity 

 of nickel present is unusually small. It is not exceptionally so, 

 for several irons have been previously analysed containing about 

 a similar or even smaller quantity. 



An examination of the Widmanstatten figures shews the iron 

 to be an octahedrite whose width of lamella? vary from 1mm. to 

 2-5mm,, the greater number, however, lying between the limits 

 of 1mm. and 2mm. Following Dr. A. Brezina* in his provisional 

 system of classification, it would be placed in Group 47, containing 

 octahedrites with broad lamellte (symbol Og) and therefore classed 

 with the Cranbourne (Victoria) and Youndegin (W. Australia) 

 meteorites more closely, and with the Cowra (N. S. Wales), 

 Moonbi (N. S. Wales), Temora (N. S. Wales), Mungindi (Queens- 

 land), and Thunda (Queensland) meteorites as being with them 

 an iron having an octahedral crystalline structure. The Nocoleche 

 iron, however, agrees much more closely with the Murfreesboro 

 one, both as regards crystalline structure and relative proportions 

 of iron and nickel. The two figures given by Dr. A. Brezinaf of 

 the latter would very well represent the structure of the former, 

 there being merely a slight difference in the average width of the 

 lamellae. 



The percentages of iron and nickel in the Murfreesboro iron 

 given by de Troost,J are as follows : — 



iron 96-0 



Nickel 2-4 



Residue 1-6 



100-0 



* Ann. K. K. Naturhist. Hofmus. Wien., x., 3-4, 1895, p. 85. 



t Ibid, p. 270. 



J Silliman's Amer. Journ. Sei. (2), v., p. 351, and Hid., xv., p. G. 



