228 Scientific Labors and Character of 



and we recognize in him, as in our own Franklin, an uncommon un- 

 ion of the philosopher with the man of strong common sense. 



The foregoing lectures, together with his public lectures as pro- 

 fessor of Chemistry at the Royal Institution, appear to have occupied 

 a great share of his attention from 1802 to 1806, when we arrive at a 

 new era in his life. It was during this and the following year, that 

 he made his brilliant discoveries in Galvanism. The discovery of 

 the metallic bases of the fixed alkalies, which has led also to the 

 knowledge of the composition of the earths, was one of the most im- 

 portant discoveries hitherto made in chemistry, and deservedly ranks 

 with the discovery of carbonic acid by Dr. Black, of oxygen gas by 

 Dr. Priestley, and of the composition of water by Mr. Cavendish. 

 Some men of intelligence, however, not particularly conversant ^vith 

 chemical science, have expressed to us their inability to comprehend 

 the reason why so much importance has been attached to the gal- 

 vanic discoveries of Davy, or why they have been rewarded with 

 such unbounded applause. To evolve from a piece of potash a me- 

 tallic globule, seems too inconsiderable a matter, to deserve the pop- 

 ularity with which the achievement has been rewarded. But they 

 do not reflect that it is one of the peculiarities of chemical analysis, 

 that discoveries made with the minutest quantities of bodies, often 

 lead to the grandest conclusions. Thus a drop of water was no 

 sooner resolved into its constituent elements, oxygen and hydrogen, 

 than a new flood of light beamed forth upon the world ; not only dis- 

 playing to the mind, in a new and more interesting view, the expanse 

 of waters, but revealing at once the cause of innumerable phenomena 

 of chemistry which depend on the agencies of water, and disclosing 

 the mysterious constitution of the vegetable kingdom. In like man- 

 ner, the kno\vledge of the composition of a particle of potash, con- 

 ducted us to a knowledge of the elementary constitution of the solid 

 globe itself. To pass by the remarkable and brilliant physical prop- 

 erties of potassium, it became, moreover, in its turn, a most powerful 

 auxiliary in investigating the composition of many other bodies ; for, 

 it was its strong aflinity for oxygen, the strongest possessed by any 

 known body, that had enabled it, under all previous trials, to disguise 

 its metallic nature ; but this oxygen being withdrawn from it, potas- 

 sium itself now became a powerful agent of analysis, appropriating to 

 itself as it does the oxygen of every other substance that contains it. 



It is far greater merit in science to discover new powers of nature, 

 or new facts which admit of exlensive ceneralization, than to arrive 



