Page:Proceedings of the Royal Society of London Vol 4.djvu/171

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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.