Vol.8. NOVEMBER 1879. No. 50. 



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



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of TillocKs 'Philosophical Magazine? 

 Nicholson's c Journal f and Thomson's 'Annals of Plmosophy.'' 



CONDUCTED BY \^\ /j&^ * 



. M.R.LA.*R$r 



SIR ROBERT KANE, LL.D. F.R.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° 50.— NOVEMBER 1879. 



WITH TWO PLATES. 



Illustrative of Dr. C. Barus's Paper on the Eelation between the Ther- 

 moelectric Properties, the Specific Eesistance, and the Hardness of 

 Steel, Mr. L. Schwendler's on a new Standard of Light, and Mr. W. 

 Grant's on the Conjugate Positions of two Circular Coils of Wire. 



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