22 Dr. Roase on a New Oxide, Sfc. 



alkalies also give precipitates. The pure alkalies re-dissolve 

 the recent precipitates, as do also the carbonates to a cer- 

 tain extent. Ferro-cyanate of potassa causes a slight whitish 

 opalescence, but tincture of galls produces no change. A 

 plate of zinc is soon covered with a slate coloured coating, 

 which, however, does not increase, but is succeeded by 

 drab flocculi, and if the solution be concentrated the whole 

 is gelatinized, and in this state is not very soluble in acids. 

 Muriate of gold does not occasion any alteration. 



The oxide, or the nitrate, heated with chlorate of potassa, 

 first becomes dark brown, and if the salt be in sufficient 

 quantity, the residue on cooling is of a bright flesh colour. 

 Well washed, an insoluble substance of same colour remains, 

 which soon decomposes giving out bubbles, and returning 

 to its brown colour ; muriatic acid makes it white with evo- 

 lution of chlorine, and nitric acid dissolves it, with extrica- 

 tion of gas. It is probably an oxide at a higher degree of 

 oxidation than the brown. 



Such is the result I had arrived at, when the oxide was 

 laid aside for more circumstantial examination, after I had 

 ascertained the nature of the other ingredients of the mine- 

 ral, one of which, is an organic acid very perplexing in its 

 composition. Should my oxide prove to be the same as 

 Mr. Richardson's Donium, my name of Treenium must of 

 course give place to his, as he first had the honour of 

 making it public, and I trust that this brief note will insure 

 to me, if not the honour, at least, the credit of also having 

 discovered Donium. 



The alumina of my substance has probably been derived 

 from decomposing granite, and I am sanguine that some 

 of the peculiarly red granites of the Land's End district, 

 will be found to contain this oxide ; and, perhaps, a re-ex- 

 amination of many minerals will shew that alumina has 

 been mistaken for this substance. 



By inserting this notice you will much oblige. Sir, 



Your obedient servant, 



Henry S. Boase. 

 Penzance, Wth Jtine, 1836. 



