§ On ilie Decomposition and Composition 



I mentioned that the metallic lustre of the substance from 

 potash immediately became, destroyed in the atmosphere, 

 and that a white crust formed upon it. This crust I soon 

 found to be pure potash, which immediately deliquesced, 

 and new quantities were formed, which in, their turn at- 

 tracted moisture from the atmosphere till the whole globule 

 disappeared, and assumed the form of a saturated solution 

 of potash*. 



When globules were placed in appropriate tubes contain- 

 ing common air or oxyjren gas confined by mercury, an 

 absorption of oxygen took place ; a crust of alkali instantly 

 formed upon the globule; but from the want of moisture 

 for its solution, the process stopped, the interior being de- 

 fended from the action of the gas. 



With the substance from soda, the appearances and effects 

 were analogous. 



When the substances were strongly heated, confined in 

 given portions of oxygen, a rapid combustion with a bril- 

 liant white flame was produced, and the metallic globules 

 were found converted into a white and solid mass, which in 

 the case of the substance from potash was found to be pot- 

 ash, and in the-case of that from soda, soda. 



Oxygen gas was absorbed in this operation, and nothing 

 emitted which affected the purity of the residual air. 



The .alkalis produced were apparently dry, or at least 

 contained no more moisture than might well be conceived 

 to exist in the oxygen gas absorbed ; and their weights 

 considerably exceeded those of the combustible matters con- 

 sumed. 



The processes on which these conclusions are founded 

 will be fully described hereafter, when the minute details 

 which are necessary will be explained, and the proportions 



* Water likewise is decomposed in the process. We shall hereafter see 

 that the bases of the fixed alkalis act upon this substance with greater energy 

 than any other known bodies. The minute theory of the oxidation of the 

 bases of the alkalis in the free air, is this : — oxygen gas is first attracted by 

 them, and alkali formed. This alkali speedily absorbs water. This water is 

 again decomposed. Hence, during the conversion of a globule into alkaline 

 solution, there is a constant and rapid disengagement of small quantities of 

 gps. 



Of 



