110 Scientific Proceedings, Royal Dublin Society. 



Difficultly Reducible Metallic Oxides. 



Three decigrams of eacli substance, fused with twelve decigrams 

 of borax in the oxidizing flame on charcoal, then nine decigrams 

 (in the case of cobalt twelve decigrams) of silver in the form of a 

 button added, and the fusion continued, the reducing flame being 

 employed. 



Iron {Ferrous sulphate) : — 



The metallic bead became quite infusible, but fused when 

 the flame was removed, a very faint trace of iron was found 

 in the metallic bead. 



Cobalt [Cobalt chloride) : — 



The metallic bead was difficultly fusible on cooling, it 

 flattened out in the way already described for cobalt {see first 

 series of experiments). It was found on testing to contain a 

 small quantity of cobalt. 



Aluminium [Aluminium phosphate) : — 



The metallic bead was somewhat infusible. Throughout 

 the fusion a considerable quantity of metallic scale appeared 

 on the glass bead. On testing the metallic bead, aluminium 

 was found present. 



Chromium [Chromium nitrate) : — 



The metallic bead was very difficultly fusible : on solidify- 

 ing, it flattened out as already described for cobalt and 

 chromium {see first series of experiments). On testing, a 

 small quantity of chromium was found present. 



Manganese [Manganous sulphate) : — 



The metallic bead was at first infusible, but became more 

 fusible towards the end of the experiment. A good deal of 

 metallic scale appeared floating on the glass bead, even before 

 the silver was added. On testing the metallic bead, manganese 

 was found present. 



It now only remains for us to make a brief reference to what 

 has been done towards the solution of the third of the questions 



