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Transactions of the Boyal Society of South Africa. 
on account of the metallic particles. These particles were readily 
separated from the other matter by means of a magnet, and formed more 
than half of the whole mass. The metallic portion is partially soluble in 
Fig. 4. X J. 
dilute sulphuric acid, and completely soluble in aqua regia. Hydrochloric 
acid attacked the powder with evolution of sulphuretted hydrogen owing 
Fig. 5. Magnification, 10 diameters. 
to decomposition of the troilite. After digestion for two days with hydro- 
chloric acid and boiling off' the sulphuretted hydrogen, the residue was 
dissolved in aqua regia. Sulphuric acid was now found in the solution, so 
