SCIENTIFIC NEWS. 



79 



SCIENTIFIC NEWS* 



Royal Society, 



T, 



HE Bakeriaii Lecture has been lately read before the chemical 



Royal Society by H.Davy, Esq. F.R.S., on Electricity con- agency of elcc- 



sidered as to its chemical agencies. Mr. Davy has found that 



a great number of bodies are capable of being decomposed 



by electricity ; particularly those containing alkalies, acids, 



alkaline earths, and metallic oxides : and he finds that their 



elements are separated in a voltaic circuit, made vf'Ah. water, jhe voltaic 



in such a way, " that all acid matter arranges itself round the current sepa- 



. , , , ._ , ,,. . , ,, It ,. ,, rates acids trom 



positively electrified metallic point, and all alkaline matter, j^eir bases; so. 



and the oxides, round the negaitively electrified point. In that the acids 

 ^,. , , • Til II I Lt arrange them- 



this way, he decomposes insoluble as well as soluble com- ^^^,^^5 ^q^^j 



pounds. Sulphuric acid and the earths are separately pro- the positive 



cured from the earthy neutral compounds, and soda and pjt- bases'round 



ash evolved from minerals and stones containing them, the negative. 



By the attracting and repellent powers of the different This povirer is 

 electricities, acid and alkaline matter are transported through |° ^-Ji^ljeve^nt 

 menstrua for which they have a strong attraction, and through the usual ef- 

 animal and vegetable substances. Thus sulphuric acid will fects ofchemi- 

 be repelled through an alkaline solution from the negative to 

 positive point, and vice versa ; potash or lime will be repelled 

 from the positive point to the negative, through an acid 

 solution. 



Mr. Davy explains these phenomena by means of some other Mr. D.'s ex- 

 experiments. As in " Voltas contacts of metals, <^opper [j^g^^ ^^"^.^5 Is 

 and zinc appear in opposite states j so Mr. Davy finds that that he finds 

 acids and alkalies, with regard to each other, and the metals, J|j^ bases to* 

 possess naturally the power of affording electricities," and possess respec- 

 may be said to be respectively in states of negative and po- "^^^^ the ne- 

 sitive electrical energies ; and the bodies naturally negative sitive states, 

 are repelled by negative electricity, and the bodies naturally ^"^ conse- 

 positive attracted by negatively-electrified points, - ■* attracted by 



the contrary 



