HADDAM AND DRAZIX.. I 1 ij 



The calcined mass was boiled in nitric acid. In this nin 

 nearly two-thirds of the matter that could not he entirelv 

 attacked in any other way, were dissolved. The same 

 treatment was repeated, until nearly (he whole of it was ta- 

 ken up, whicli happened alter the fourth calcination. It was 

 then no fuithei- acted on. 



After makin.2; numerous experiments on the matter that 

 resisted nitrate of harytes atnl nitric acid, 1 ascertainorl, tiiat 

 it was not acted on hy alkalies nor acids when used sepa- 

 rately, hut after having been previously calcined with caus- 

 tic potash, it readily dissolved in muriatic acid, yielding a so- 

 lution of a pale yellow colour, wliich gave a reddish preci- 

 pitate with an infusion of galls, a deep green precipitate 

 with the hydrosulphatc of potash, and a white precipitate 

 with alkalies. Hence it was oxide of titanium. 



After the barytes was separated with sulphuric acid, the 

 nitric solutions were united, and treated with an excess of 

 subcarbonate of ammonia. An abundant precipitate ensu- 

 ed, which entirely re-dissolved in the excess of subcarbo- 

 nate. By ebullition it was again precipitated, and when 

 calcined, it was in the form of a liglit white powder, jiosses- 

 sing all the properties that characterise Gfitcina. With the 

 sulphuric and muriatic acids it formed very sweet as^trin- 

 gent deliquescent salts. By caustic potash it was precipi- 

 tated from its solutions, and the precipitate re-dissolved in 

 the excess of the alkali. Klaprotb and Arfwedson. in ihcir 

 analyses of the Chrysoberyl from Brazil, considered the iti- 

 solublc matter remaining after they had treated the mineral 

 with potasli and muriatic acid, to l)e Silira. This will ex- 

 plain why their results dillerso essentially from mine. 



After having thus satisfied myself of the comp(tsition of 

 the residue above mentioned. I resumed my preliminary ex- 

 periments, and jiroceeded to examine the muiialie solution 

 ol)tained from the treatment of the mineral with potasb and 

 muriatic acid. From this solution some silica was separated. 

 A portion of tlie liquifl was treated with caustic ammonia, 

 and then tested for Li?ne with oxalate of potash, but none 



