101 



yellowish tinge which it generally has, and on essaying it, I 

 found it free from any impurity but a little carbonic acid, and 

 a trace of platina from the crucible, A fragment of it exposed 

 on charcoal to the flame entered into the same watery fusion 

 as the carbonate, and was dissipated with the coloured flame. 

 When it was placed on a fragment of Wedgewood's ware, avoid- 

 ing the fusion of the support, the appearances were rather dif- 

 ferent ; during the few seconds which elapsed before it acquired 

 the teinperature of the flame, some hydrate was formed which 

 melted, but the remainder resisted fusion, and was changed into 

 a sort of frit ; this evolved the usual flame, and it was obvious 

 that the reduction was taking place. In this and subsequent 

 experiments, I examined the residue for the metallic lustre, but 

 I never certainly found it, and I do not think that any hydro- 

 gen was disengaged when these residues were passed into dilute 

 muriatic acid over mercury ; some gas was liberated, but I sus- 

 pect it to have been carbonic acid, as it was totally absorbed 

 by ammoniacal gas when added in excess above what was re- 

 quired to saturate -the, acid (e). I am therefore inclined to 

 think that the barium was volatilized as fast as it was formed. 

 The various bodies on which 1 have tried experiments are, 

 with few exceptions, fused in a few minutes, shivers of gunflint 

 melt rapidly into globules, hydrate of alumine is rather more 

 refractory, the subsulphate of it is easily fusible. Magnesia wa» 

 blown away by the blast, but 4 parts of it with 1 of hydrate of 

 alumine gives a clear glass. Lime is most untractable, the 



(e] Tlie first specimens of barytes which I obtained gave a gas wliich was not absorbed 

 by this treatment : I suspect that it was oxygen from peroxide of barium, as they vi-ere 

 deprived of this property by the application of a violent heat. 



