i) MAY 1885. No. 120. 
Published the First Day of every Month.—Price 2s. 6d. 
THE 
LONDON, EDINBURGH, anp 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.LA. F.C.S. 
SIR WILLIAM THOMSON, Knr. LL.D. F.RS. &e. 
AND 
WILLIAM FRANCIS, Puz.D. F.L.S. F.R.A.S. F.C.S. 
FIFTH SERIES. 
N° 120.—MAY 1885. 
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