GALVANISM. 



had propounded, and to the realization of the ideas he had ventured to throw 

 out respecting the resolution of natural substances, before regarded as simple, 

 into their constituents. Never before did theory more surely lead to discov- 

 ery ; never was the prophetic instinct of a philosopher more speedily or more 

 magnificently satisfied. His foreknowledge of the facts to be disclosed and 

 the instruments for their disclosure, of the end to be attained and the means 

 of attaining it, of the route to be followed and the goal to be reached, was dis- 

 tinctly expressed ; and with the confidence inspired by clear perceptions and 

 conscious power, he immediately advanced in the course he described, ar,J 

 attained the end he foresaw. The resolution of the alkalies and earths into 

 their elements was the splendid result of his labors during the year 1807, and 

 was consigned to the Bakerian lecture read before the Royal Society on the 

 19th of November in that year. 



His first efforts were directed to potash, which was submitted in a state of 

 solution to the electric current. The water only was decomposed, the alkali 

 refusing to yield. In its dry state it would not transmit the current. In order 

 to give it. a conducting power, and at the same time exclude water, on which 

 by preference the current appeared to act, the alkali was now placed in a pla- 

 tinum spoon, and exposed to the flame of a lamp directed upon it by a blast of 

 oxygen. When reduced to the fluid state by such means, the potash transmit- 

 ted the Voltaic current. When the metal of the spoon was positive, and the 

 point of a platinum wire inserted in the fluid alkali negative, combustion at- 

 tended by intense splendor was exhibited at the wire, and a column of flame 

 arose from the point of contact of the wire with the alkali. When the spoon 

 was negative, and the wire positive, a vivid light appeared on the former ; 

 aeriform globules rose through the liquid potash, which inflamed as soon as 

 they escaped into the air. 



It was conjectured that the constituent of the potash, attracted by the n^ Da- 

 tive pole, was the matter which in these cases escaped in bubbles ; and that 

 its affinity for oxygen was so strong, that the moment it came in contact with the 

 atmosphere it recombined with oxygen and produced combustion. The question 

 therefore, now was, how to arrest that element, and submit it to examination. 



As the liquefaction of the alkali by heat appeared to entail, as a conse- 

 quence the immediate recombination of its separated constituent, it was nov 

 attempted to give the necessary conducting power to the potash, by allowing 

 it to imbibe from the atmosphere as much moisture as would give a conducting 

 power to its surface. The alkali in this state was placed on a platinum disk, 

 which was connected with the negative pole, while a wire connected with the 

 positive pole was applied to its upper surface. At the upper surface, there was 

 a disengagement of gas ; at the lower surface small metallic globules appeared, 

 like mercury, in their visible character. Some of these burnt by contact wi?.h 

 the air. Others had their metallic lustre tarnished, and finally covered with a 

 white film, which defended them from the atmosphere, and preserved them in 

 their metallic state. 



The gas disengaged at the positive wire was oxygen, and the metal depos- 

 ited was the base of the alkali, afterward called POTASSIUM. 



Soda, when submitted to a like process, gave a similar result, and the metal 

 educed from it was that which is now called SODIUM. 



This capital discovery was made in October, 1807. Potassium was dis- 

 covered on the 6th of that month, and sodium a few days after. 



Sensitive friends of the great British chemist have been moved to vindicate J 

 the glory of this discovery from those who would tarnish it by ascribing to the j 

 accidental possession of the laboratory and apparatus of the Royal Institution j 

 of Great Britain a share in producing it These generous survivors may tran- j 



