Vol.7. APRIL 1879. No. 43. 



Published the First Day of every Month. — Price 2s. 6d. 



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE. 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloch's 'Philosophical Magazine,' 

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



CONDUCTED BY 



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

 SIR WILLIAM THOMSON, Knt. LL.D. F.R.S. &c. 



AND 



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



FIFTH SERIES, 



N° 43.— APRIL 1879. &L 



WITH TWO PLATES. < 



Illustrative of Dr. O. J. Lodge's paper on the Determination of the 

 Variation of the Thermal Conductivity of Metals with Temperature, 

 and Messrs. Ayrton and Perry's on a new Determination of the 

 Ratio of the Electromagnetic to the Electrostatic Unit of Electric 

 Quantity. 



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