380 Notices respecting Neiv Books. 



by placing it between the wires of a battery; the repetition of 

 Gay-Lussac and Thenard's very important process for preparing 

 potassium; and his attempts to decompose the earths. With respect 

 to the latter Dr, Paris remarks, " his results were indistinct : they 

 could not, like the alkalies, be rendered conductors of electricity 

 by fusion, nor could they be acted upon in solution, in conse- 

 quence of the strong affinity possessed by their bases for oxy- 

 gen." While engaged on this subject he received a letter from 

 Berzelius, announcing the fact that he, in conjunction with Pontin, 

 had decomposed barytes and lime by negatively electrizing mercury 

 in contact with them, and thus had obtained amalgamsof the bases of 

 those earths : these experiments were repeated by Davy with many 

 in addition, and an account of them was read before the Royal 

 Society on the 30th of June 1808. The memoir was entitled 

 •' Electro-chemical Researches on the Decomposition of the Earths; 

 with Observations on the Metals obtained from tliem, and on the 

 Amalgam of Ammonia." 



It will not be requisite to enter into a discussion on the nature 

 of the amalgam ; the appearances which it presents have not been 

 explained. But that hydrogen and azote are metals, or contain any- 

 thing metallic, will scarcely now be maintained ; the amalgama- 

 tion is probably merely apparent, and the recent experiments of 

 Mr. Daniell tend to confirm this opinion. 



In 1808 Davy read his third Bakerian Lecture j the title of it is 

 " An Account of some new Analytical Researches on the Nature of 

 certain Bodies, particularly the Alkalies, Phosphorus, Sulphur, Car- 

 bonaceous matter, and the Acids hitherto undecompounded ; with 

 some general Observations on Chemical Theory." Of this excellent 

 paper Dr. Paris gives an analysis. So sanguine was Davy's hope of 

 decomposing some substances which have even yet resisted analysis, 

 that he addressed a letter to Mr. Children during the progress of 

 his experiments; in which he says, " I hope on Thursday to show 

 you nitrogen as a complete wreck, torn to pieces in different ways." 

 In a letter to the above-named gentleman, dated September 23, 

 1809, we also meet with some opinions which subsequent investiga- 

 tions have by no means corroborated. " I doubt not," he says, "you 

 have found before this, as I have done, that the substance we mis- 

 took for sulphitretted hydrogen is telluretted hydrogen, very soluble 

 in water, combinable with alkalies and earths, and a substance 

 affording another proof that hydrogen is an oxide." He says also, 

 " I find that taking ammonium as the basis of hydrogen, according 

 to the ideas which I stated, all the compounds will agree with the 

 suppositions that I mentioned to you, viz. eight cubic inches of hy- 

 drogen, two of oxygen, ammonia j _yb7<r and two, xvater ; four and 

 four, nitrogen ; four and six, nitrous oxide ; four and eight, nitrous 

 gas; four and ten, nitric acid." 



We need hardly observe that of the opinions here mentioned, 

 that only which we have printed in italics is to be found in his 

 *' Elements of Chemical Philosophy," printed within three years 

 from the date of this letter. 



This 



