30 



M. Bonsdorfon the 



[July, 



The next attempt was to expose the mineral to the action of 

 hydrogen gas, while at the same time heat was applied to it, in 

 hopes that the hydrogen would reduce the oxide of antimony to 

 the metallic state and form water, by the weight of which the 

 quantity of oxygen in the mineral could be determined. But in 

 order to satisfy myself in the first place that this theoretic spe- 

 culation would accord with the nature of the bodies present, I 

 undertook a set of experiments on the reduction of an artificial 

 mixture of sulphuret and oxide of antimony by means of hydro- 

 gen gas. 



The apparatus which was employed in these processes was 

 constructed on almost the same idea as that described by Prof. 

 Berzelius in his experiments on nickel glanse, arsenical nickel, 

 &c. ; an outline of which is here given. 



fflm$imM$ $ 



It consisted of a globular vessel, A, in which the gas was 

 generated, a tube, C, filled with chloride of calcium, and a small 

 apparatus for distilling. But this last apparatus, distinguished 

 in the figure by the letters D E F G H, was, in my experiments, 

 not terminated by the ball, F, and the crooked tube, G H ; but 

 had on that side merely a straight tube rather more than two 

 inches long, which was fastened to the ball, E, by a caoutchouc 

 tube in the same way as the apparatus, D E, only somewhat 

 greater. This tube was filled with chloride of calcium in the 

 same way as the tube C, and from A there passed a crooked 

 tube to allow the gas evolved to make its escape. The gas was 



