CONTENTS OF VOL. IX. 



(FOURTH SERIES.) 



NUMBER LVL— JANUARY 1855. 



Page 

 Mr. W. R. Grove on a Method of increasing certain Effects of 



Induced Electricity 1 



M. V. Regnault on the Elastic Forces of Vapours in vacuo and 

 in Gases, at different Temperatures ; and on the Tensions 

 of the Vapours furnished by mixed or superposed Liquids 



(concluded) 4 



Sir J. W. Lubbock on the Heat of Vapours 25 



Mr. A. B. Northcote on the Brine-springs of Worcestershire. . 27 

 Prof. \V. Thomson on the Possible Density of the Luminiferous 

 Medium and on the Mechanical Value of a Cubic Mile of 



Sunlight 36 



The Rev. J. A. Galbraith on the Composition of the Felspars 



of the Granite of the Dublin and Wicklow Mountains 40 



Prof. Magnus on the Elastic Forces of Vapours of Mixtures of 



two Liquids 44 



Sir W. R. Hamilton on some Extensions of Quaternions (con- 

 tinued) 46 



The Rev. A. Thacker on a case of disturbed Elliptic Motion. . 51 

 Notices respecting New Books : — Mr. T. Hopkins on the 

 Atmospheric Changes which produce Rain and Wind, and the 



Fluctuations of the Barometer 54 



Proceedings of the Royal Society 56 



On a peculiar Phaenomenon in the Electro-deposition of Anti- 

 mony, by Mr. G. Gore 73 



On the Composition and Properties of Fats, by D. Heintz. ... 74 



On Phillyrine, by C. Bertagnini 78 



Meteorological Observations for November 1854 79 



Meteorological Observations made by Mr. Thompson at the 

 Garden of the Horticultural Society at Chiswick, near 

 London; by Mr. Veall at Boston; and by the Rev. C. 

 Clouston at Sandwick Manse, Orkney 80 



NUMBER LVIL— FEBRUARY. 



Prof. Faraday on some Points of Magnetic Philosophy 81 



M. W. Eisenlohr on the Action of the Violet and Ultra-violet 

 Invisible Light 114 



