Vol.6. SEPTEMBER 1878. No. 36, 



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 Tilloch's ( 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. &o. 



AND 



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



FIFTH SERIES. ^ 



j 

 N° 36.— SEPTEMBER 1878. 3 



WITH A PLATE. 



Illustrative of Mr. J. E. H. Gordon's Paper on the Effect of Variation of 

 Pressure on the Length of Disruptive Discharge in Air. 



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