Vol. 22, JULY 1886. No. 134 



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 TillocKs '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. 

 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° 134.-JULY 1886. 





WITH ONE PLATE. 



Illustrative of Prof. Wiedemann's Magnetic Researches. 



LONDON: 



PRINTED BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET, 



Sold by Longmans, Green, and Co. ; Xent and Co. ; Simpkin, Marshal], and Co. ; 

 and Whittaker and Co. ;— and by A. and C. Black, and T. and T. Clark, Edin- 

 burgh ; Smith and Son, Glasgow : — Hodges, Foster, and Co., Dublin : — Putnam, 

 New York : — Veuve J. Boyveau, Paris : — and Asher and Co., Berlin. 



