﻿An**- 



fol. 41. MARCH 1871. No. 272. 



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THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloch's e Philosophical Magazine/ 

 Nicholson's 'Journal,' and Thomson's ' Annals of Philosophy.' 



CONDUCTED BY 



SIR ROBERT KANE, LL.D. F.R.S. M.R.I.A. F.C.S. 



AND 



WILLIAM FRANCIS, Ph.D. F.L.S. F.R.A.S. F.C.S. 



FOURTH SERIES. 



N° 272.— MARCH 1871. 



WITH THREE PLATES, 



Illustrative of Prof. R. Bunsen's Calorimetric Researches, and Mr. W. 



R. Birt's Investigations relative to Lunar Activity. 



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