MancJiester Memoirs, Vol. hii. (191 3), No. Id. 17 



discovery of ammonium amalgam threw new light on the 

 matter. The experiments concerning it are described in 

 the following letter by Charles Blagden ' to Thomas 

 Thomson.^ 



. . . The chemists here have not succeeded in the French 

 experiment of obtaining the basis of potash pure in the 

 dry wa)' ; they get only an alloy of iron and the basis. 

 But two Swedish chemists, Berzelius'' and Pontin/" 

 have applied the affin.ity of the bases for mercury very 

 advantageously, and by means of it decomposed 

 ammonia calx, barytes, etc. The substances to be 

 decomposed must be put into contact with the mercury 

 and the galvanic current forced through. Carbonate 

 of ammonia being laid upon the quicksilver, the latter 

 is soon made by the galvanism to swell up to several 

 times its original bulk, and to assume the appearance 

 of an amalgam, which being thrown into water gradu- 

 ally shrinks back to its original size, and becomes 

 running quicksilver as before; it is a beautiful 

 experiment. 



The Swedes suppose that the hydrogene and 

 azote of the ammonia combine to form a metal, which 

 thus unites to the mercury. Mr. Davy thinks rather 

 that hydrogene and azote are both metals in a state of 

 vapour, which both unite to the mercury and form a 

 triple compound with it. Mr. Davy has successfully 

 repeated all the experiments, and has decomposed in 

 that manner 6 earth-baryte, lime, magnesia, silex, 



and alumine 



London, 7/7/1808. CHARLES BlaGDEN. 



'' Sir Charles Blagden (1748-^820), physician, Secretary of the Royal 

 Society. 



^ Thomas Thomson (1773-1852), chemist. Supporter of Dalton's theory 

 and author of a ' History of Chemistry.' 



® Jons Jacob Berzelius. The great chemist. (1779-1848.) 



1" Magnus Pontin of Pontin(i78i-i858). Swedish physician and author. 

 Collaborated occasionally with his friend Berzelius, whose biography he wrote. 



