EXPERIMENTS ON THE METALS rROM THE MXED ALKAtlS. 3£3 



chemists have expressed themselves satisfied both with the 

 experiments, and the conclusions drawn from them: 

 but as usually happens in a state of activity in science, and 

 when the objects of inquiry are new, and removed from 

 the common order of facts, some inquirers have given 

 hypothetical explanations of the phenomena, different from 

 those I adopted. 



Messrs. Gay-Lussac and Thenard, as I have mentioned 

 on a former occasion, suppose potassium and sodium to be 

 compounds of potash and soda with hidrogen ; a similar 

 opinion seems to be entertained by Mr. Ritter. Mr. 

 Curaudau* affects to consider them as combinations of 

 charcoal, or of charcoal and hidrogen, with the alkalis; 

 and an inquirer + in our own country regards them as com- 

 posed of oxigen and hidrogen, 



I shall examine such of th«se notions only as have been 

 connected with experiments, and I shall not occupy the 

 time of , the Society with any criticisms on matters of mere 

 speculation. 



In my two last communications, I have given an account Gay-Lussac and 



of various experiments on the action of potassium upon Thenard's 



ammonia, the process from which Messrs. Gay-Lussac and action of potas- 



Thenard derive their inferences. At the time that these sium . on am ~ 



moma, 



papers were written, I had seen no other account of the 

 experiments of the French chemists, than one given in a 

 number of the Moniteur ; and as this was merely a sketch, 

 which I conceived might be imperfect, I did not enter into 

 a minute examination of it. I have since seen a detail of 

 their inquiry in the second volume of the Mem. d'Arcueil, 

 a copy of which Mr. Berthollet has had the goodness to 

 send me, and the publication of which is dated June 7, 

 1809: and from this detail it seems, that they still retain 

 their Opinion ; but upon precisely the same grounds as 

 those, to which I have before referred. That no step of 

 the discussion may be lost to the Society, I shall venture 

 to state fully their method of operation, and of reason- 



* Journal de Physique, June, 1808 ; or Journal, vol. xxiv ; p. 40. 

 f Nicholson's Journal, August, 1809, p. 258 



Y2 They 





