488 



INDEX. 



Unitation, on, 346. 



Vanilla, on the conversion of conife- 

 rine into the aromatic principle of, 

 229. 



Vapours, on the molecular structure 

 of, in connexion with their densi- 

 ties, 320. 



Venus as a luminous ring, on, 159. 



Vision, on the mixture of colours in 

 binocular, 78. 



Volcanic energy, on, 144. 



Walenn (W. H.) on unitation, 346. 



Water, on the decomposition of, by 

 iron, 413. 



Watts (Dr. W. M.) on carbon and 

 hydrocarbon in the modern spec- 

 troscope, 104; on the spectrum of 

 the aurora, 410. 



Weber (Dr. H. F.) on the specific 

 heat of the elements carbon, boron, 

 and silicon, 161, 276. 



Weiser (R.) on permanent ice in a 

 mine in the Rocky Mountains, 77* 



Wullner (Prof.) on spectra of gases, 

 448. 



END OF THE FORTY-NINTH VOLUME. 



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