Vol.6. OCTOBER 1878. iNo.37 



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



THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE, 



AJSTD 



JOURNAL OF SCIENCE. 



Being a Continuation of Tilloclis 'Philosophical Magazine, 

 Nicholsons '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. Ac. 



AND 



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



_ . 



FIFTH SERIES. ^ 



N° 37.— OCTOBER 1878. £ 



WITH TWO PLATES. 



Illustrative of the Rev. J. F. Blake's Paper on the Measurement of 

 the Curves formed by Cephalopods and other Mollusks, and Prof. 

 E. Edlund's on Unipolar Induction, Atmospheric Electricity, and 

 the Aurora Borealis. 



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