Vol. 34. DECEMBER 1892. No. 211 



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





THE v- 



LONDON, EDINBURGH, and DUBLLN> 



PHILOSOPHICAL MAGAZlftJS, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloctis 'Philosophical Magazine, 9 

 Nicholson's 'Journal? and Thomsons 'Annals of Philosophy.' 



CONDUCTED BY 



LORD KELVIN, LL.D. P.R.S. &c. 



GEORGE FRANCIS FITZGERALD, M.A. Sc.D. F.R.S. 



AND 



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



FIFTH SERIES. 



N° 211.— DECEMBER 1892, 



LONDON: 



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



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