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fluid, but a formation of small globules, having a bright metallic 

 splendour and a perfect resemblance to quicksilver ; but they tarnished 

 rapidly at their surface, and were in general soon covered by a white 

 film, but occasionally burned with explosion and a white flame. 



These globules were soon proved, by numerous experiments, to be 

 a peculiar inflammable principle, the basis of potash. 



The platina used, as the medium, for communicating the electric 

 power, was proved not to have contributed otherwise to the result 

 than as a conductor ; for by substituting other conductors, as copper, 

 silver, gold, plumbago, or charcoal, the same substance was formed 

 by means of them. Its formation was also independent of the pre- 

 sence of air, as it took place equally under an exhausted receiver. 



Soda, when acted upon in the same manner, and under similar cir- 

 cumstances, exhibited analogous results ; but it required far greater 

 intensity of action, and could not be decomposed in pieces which 

 exceeded fifteen or twenty grains in weight. 



That the substances thus produced were evolved by the decom- 

 position of the alkalies, was proved by careful examination of the 

 gas extricated from the upper surface, which was found to be pure 

 oxygen ; and again proved synthetically, by ascertaining that they 

 absorbed oxygen gas, to which they were exposed, and that the com- 

 pounds resulting were, in fact, the respective alkalies that had been 

 employed for their formation. 



The affinity of the base of potash for oxygen is such, that its me- 

 tallic lustre very rapidly tarnishes in the atmosphere, by the forma- 

 tion of a white crust, which, by attracting moisture, is soon converted 

 into a saturated solution of potash. 



With the base of soda the phenomena are perfectly analogous, but 

 less rapid ; and when either of them is heated in oxygen gas, a rapid 

 combustion, with brilliant white flame, is produced. Oxygen gas is 

 absorbed in this process, and nothing emitted to affect the purity of 

 the residual air. 



It appears, then, says Mr. Davy, that in these facts there is the 

 same evidence for the decomposition of potash and soda into oxygen 

 and their peculiar bases, and for their recomposition, that there is for 

 the decomposition and formation of any metallic oxide, or of the 

 sulphuric or phosphoric acids. 



In the analytic experiments no substances are present but the al- 

 kalies and a minute portion of water, which, in its common form, 

 seems in no other way essential to the result, than by rendering them 

 capable of becoming fluid, and conductors at a lower temperature 

 than that at which their combustible bases burn ; for if the quantity 

 of water be increased, no such result is obtained. 



These bases seem to be repelled, as other combustible substances, 

 by positively electrified surfaces, and attracted by negative surfaces, 

 and hence are formed at that side in the electric circuit. 



The properties of these bodies are such, that in the first place it is 

 extremely difficult to preserve them, and to confine them for experi- 

 ments ; such is their affinity for oxygen, that they act on almost 



