I* 



K 37. JUNE 1894. No. 229, 



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



THE 

 ' LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AND 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloelis 'Philosophical Magazine,' 

 Nicholson s 'Journal,* and Thomson's '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° 229.— JUNE 1894. 



>!rPff 



LONDON: 



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



Id by Simpkin, Marshall, Hamilton, Kent, and Co., Ld.; Whittaker and Co. ; 

 and "by A. and C. Black ; — T. and T. Clark, Edinburgh ; Smith and Son, 

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