Vol.3. JUNE 1877. No. 20. 



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 TillocJis 'Philosophical Magazine, 1 * 

 Nicholson's 'Journal ,' and Thomson's 'Annals of Philosophy.'' 



CONDUCTED BY 



SIR ROBERT KANE, LL.D. F.R.S. M.R.I.A. F.O.S. 

 SIR WILLIAM THOMSON, Knt. LL.D. F.R.S. &c. 



AND 



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



FIFTH SERIES. 



N° 20.— JUNE 1877. 



WITH TWO PLATES, 



Illustrative of Mr. J. P. Harrison's Paper on the supposed Diathermancy 

 of Bock-Salt, and Mr. W. J. Lewis's Crystallographic Notes. 



With this (the regular Number for June 1877) is published, and 

 should be delivered to Subscribers, the Supplement (No. 21) toVol. III. 

 containing papers by Dr. Bornstein, Dr. E. J. Mills, Prof. E. Edlund, 

 Mr. P. E. Batnes, Mr. O. J. Lodge, and Mr. N. S. Maskeltne, 

 together with Notices respecting New Books, Proceedings of the Royal 

 and Geological Societies, Intelligence and Miscellaneous Articles, and the 

 Title-page, Table of Contents, and Index to Vol. HI. 



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