572 Analysis of Books, fyc. 



His third Bakerian Lecture was read before the Royal Society 

 in December, 1808 : it contained his * Researches on the nature of 

 certain Bodies, particularly the Alkalies, Phosphorus, Sulphur, 

 Carbonaceous Matter, and the Acids hitherto undecompounded; 

 with some observations on Chemical Theory.' These inquiries are 

 continued and extended in a paper read before the Royal Society in 

 February, 1809, and in his fourth Bakerian Lecture, published in 

 that year. The contents of these papers will hardly admit of 

 analysis or abridgment, but Dr. Paris has given an account of the 

 general results : these consist of his account of the mutual action of 

 potassium and ammonia upon each other; in the course of which he 

 obtained an olive-coloured substance, which he was inclined to 

 regard as the metallic base of ammonia : he also believed that 

 nitrogen had been decomposed during the process, and that its 

 elements were oxygen and a metallic base, or oxygen and hydrogen. 

 His attention was called to tellurium by an observation of Ritter, 

 that, of all the metallic substances, it was the only one by which he 

 could not procure potassium through the agency of negative 

 electricity. In pursuing the inquiry, Davy found that tellurium and 

 hydrogen were capable of combining and of forming a gas, to 

 which he gave the name of 'telluretted hydrogen; and that so far from 

 preventing the decomposition of potash, it formed an alloy with 

 potassium when negatively electrified upon the alkali, and had the 

 most intense affinity with it. The results of his inquiry whether 

 sulphur, carbon and phosphorus in their ordinary form may not 

 contain hydrogen, were far from conclusive. He succeeded in 

 decomposing boracic acid, but was anticipated in some of his 

 results by Gay-Lussae and Thenard. He at first proposed to call 

 the base of that acid boracium ; but, finding it more analogous to 

 carbon than any other substance, he adopted the term boron. ' His 

 experiments and reasonings upon muriatic acid, at this period 

 (says Dr. Paris), derive their greatest interest from their fallacy, and 

 the vigour he subsequently displayed in disentangling himself from 

 a web of his own fabrication.' 



At this period, on his representation, a splendid voltaic battery 

 was constructed, the means being raised by a subscription among 

 the members of the Royal Institution for the purpose. It consisted 

 of 200 troughs, each containing 10 double plates, arranged in cells 

 of porcelain, and containing, in the whole, a surface of metal of 

 128,000 square inches. All the phenomena of chemical decomposi- 

 tion were produced with intense rapidity by this combination; and 

 he instituted several experiments with the hope, already alluded to, 

 of decomposing nitrogen. 



The evidence by which Davy established the important fact that 

 oxymuriatic acid is a simple body, which becomes muriatic acid by 

 its union with hydrogen, was deduced from a course of experiments 

 conducted with the most consummate skill and perseverance; the 

 results of which were given to the world in his Bakerian Lectures 



