ChenuQal K^iicfs^ t^t 



CHEMlCAI^ NOTICES. 



The following is an extract of a letter from U. P. Salmouj, 

 Phyfician to the French Army m Italy, to Profeflbr Mafcagnj, 

 of Sienna; 



*^ Brugnatclli is much employed ^i prefent in repeating , 

 the experiments pf Volta on the folution of metals by what 

 he calls the ele6lric acid. I have feen fome of his ele6lrats of 

 filver, which are the moft lingular phseaomenon I ever heard 

 of. Befides other curious obfervations, Brugnatclli has eoj^- 

 firmed the difcovcry of the' chemical alteration of metals by the 

 electric fluid. He has proved, by an exceedingly curious ex^ 

 periment, before made by Volta, that electricity decompofes 

 water ; that it feizes on the oxygen difengaged 5 and that, in 

 this combination, it acquires the aftonifliing property of dif- 

 folving filver and reducing it to the faline ftate. This may be 

 eafily tried : nothing is neceflary but to adjuft to Volta's appa- 

 ratus a filver conductor the two branches of which are each im- 

 merfed in a glafs of water. Scarcely is this communication 

 cftabliftied, when you will obferve a multitude of fmall bub-' 

 bles moving in a vortex around the branch of the conductor, 

 which receives from the apparatus the eleftric fluid, while 

 from the oppofite branch there proceeds a cloud of a cylindric 

 form, which dcfcends to the bottom of the veflel. If the free 

 gas, difengaged from the branch where the ele6lric fluid 

 enters, be colleCled, it will be found to be pure hydrogen : 

 you will find alfo, by infpefting the branch immerfed in the 

 fecond veflel, that the filver has not only been diflblved, but 

 that a large quantity of very brilliant dodecaedral cryftals has 

 been formed. If an arc of gold be fubftituted for the filver 

 condu6lor, the branch which receives the eleftricity and the 

 extremity where it ifllies will in like manner be covered with 

 bubbles, and the aeriform fluid collected is detonating gas. 

 The gold, however, has experienced no altera lion. It is 

 therefore evident that ele6lricity a£ls as a powerful acid ; it 

 appears alfo to be fufceptible of becoming oxygenated in the 

 dccompofition of water, of being flrongly charged with the 

 acidifying principle, and of afterwards extending its action 

 to the metals, with which it produces peculiar falls. The 



falts- 



