Vol. 35. JUNE 1868. No. 239. 



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THE 

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PHILOSOPHICAL MAGAZINE, 



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JOURNAL OF SCIENCE. 



Being a Continuation of Tilloch's 'Philosophical Magazine,' 

 Nicholson's l Journal f and Thomson's 'Annals of Philosophy. 9 



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FOURTH SERIES, 



N° 239.— JUNE 1868. 



WITH A PLATE, 



Illustrative of M. Berthelot's Paper on a New Thermometer for measuring 

 Temperatures above the Boiling-point of Mercury, and Mr. J. Gill's 

 on the Dynamical Theory of Heat. 



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