« 



PROCEEDINGS 



OF 



THE ROYAL SOCIETY. 



1839. No. 39. 



May 30, 1839. 



The MARQUIS OF NORTHAMPTON. President, in the Chair. 



Professors Christopher Hansteen, Macedoine Melloni, Lambert 

 Adolphe Jacques Quetelet and Felix Savart, were severally elected 

 Foreign Members of the Society. 



Edward Davies Davenport, Esq., James Orchard Halliwell, Esq., 

 Gilbert Wakefield Mackmurdo, Esq., and the Venerable Charles 

 Thorp, D.D., were balloted for, and duly elected into the Society. 



John Howship, Esq., was balloted for, but not elected into the 

 Society. 



The reading of a paper entitled, " Fifth letter on Voltaic Com- 

 binations; with some account of the eiFects of a large Constant 

 Battery: addressed to Michael Faraday, Esq., D.C.L., F.R.S., Ful- 

 lerian Professor of Chemistry in the Royal Institution of Great Bri- 

 tain. By John Frederic Daniell, Esq., F.R.S., Professor of Che- 

 mistry in King's College, London," was resumed and concluded. 



The author, pursuing the train of reasoning detailed in his pre- 

 ceding letters, enters into the further investigation of the variable 

 conditions in a voltaic combination on which its efficiency depends ; 

 and the determination of the proper proportions of its elements for 

 the economical appHcation of its power to useful purposes. He 

 finds that the action of the battery is by no means proportioned to 

 the surfaces of the conducting hemispheres, but approximates to the 

 simple ratio of their diameters ; and hence concludes that the cir- 

 culating force of both simple and compound voltaic circuits in- 

 creases with the surface of the conducting plates surrounding the 

 active centres. On these principles he constructed a constant bat- 

 tery consisting of seventy cells in a single series, which gave, be- 

 tween charcoal points separated to a distance of three-quarters of 

 an inch, a flame of considerable volume, forming a continuous arch, 

 and emitting radiant heat and light of the greatest intensity. The 

 latter, indeed, proved highly injurious to the eyes of the spectators, 

 in which, although they were protected by grey glasses of double 

 thickness, a state of very active inflammation was induced. The 

 whole of the face of the author became scorched and inflamed, as if 

 it had been exposed for many hours to a bright midsummer's sun. 



