SIR HUMPHREY DAVY 185 



rated at common temperatures, by the highest electrical power I could 

 command, and which was produced by a combination of Voltaic bat- 

 teries belonging to the Royal Institution, containing 24 plates of 

 copper and zinc of 12 inches square, 100 plates of 6 inches, and 150 

 of 4 inches square, charged with solutions of alum and nitrous acid ; 

 but in these cases, though there was a high intensity of action, the 

 water of the solutions alone was affected, and hydrogen and oxygen 

 disengaged with the production of much heat and violent efferves- 

 cence. 



The presence of water appearing thus to prevent any decomposi- 

 tion, I used potash in igneous fusion. By means of a stream of 

 oxygen gas from a gasometer applied to the flame of a spirit lamp, 

 which was thrown on a platina spoon containing potash, this alkali 

 was kept for some minutes in a strong red heat, and in a state of 

 perfect fluidity. The spoon was preserved in communication with 

 the positive side of the battery of the power of 100 of 6 inches, highly 

 charged; and the connection from the negative side was made by 

 a platina wire. 



By this arrangement some brilliant phenomena were produced. 

 The potash appeared a conductor in a high degree, and as long as 

 the communication was preserved, a most intense light was exhibited 

 at the negative wire, and a column of flame, which seemed to be 

 owing to the development of combustible matter, arose from the 

 point of contact. 



When the order was changed, so that the platina spoon was made 

 negative, a vivid and constant light appeared at the opposite point : 

 there was no effect of inflammation round it ; but aeriform globules, 

 which inflamed in the atmosphere, rose through the potash. 



The platina, as might have been expected, was considerably acted 

 upon ; and in the cases when it had been negative, in the highest 

 degree. 



The alkali was apparently dry in this experiment ; and it seemed 

 probable that the inflammable matter arose from its decomposition. 

 The residual potash was unaltered ; it contained indeed a number of 

 daik grey metallic particles, but these proved to be derived from the 

 platina. 



I tried several experiments on the electrization of potash rendered 

 fluid by heat, with the hopes of being able to collect the combustible 



