CONTENTS OF VOL. XVI. 



NUMBER C— JANUARY, 1840. Page 



On th.e Theory of Substitutions in Chemistry, proposed by M . 



Dumas. In a Letter to M. Pelouze from M. Berzelius .... 1 

 Mr. Jeffreys's Experiments on Mechanical Exosmose with refer- 

 ence to determining the Existence of any difference of Mag- 

 nitude between liquid and gaseous Particles 10 



Mr. R. Potter on Photometry in connexion with Physical 



Optics 16 



Mr. Gulliver's Observations on the Blood Corpuscles or Red 



Disks of the Mammiferous Animals. No. 1 23 



Mr. J. T. Cooper on the Employment of Carbon in Voltaic 



Combinations 35 



Prof. Sylvester on Derivation of Coexistence : Part I, Being 



the Theory of simultaneous simple homogeneous Equations 37 

 Dr. Schafhaeutl on the Combinations of Carbon with Silicon 

 and Iron and other Metals, forming the different species of 



Cast Iron, Steel, and Malleable Iron 44 



Mr. HalliweU's Observations on the Authenticity of the Pass- 

 age in the Treatise of Boetius de Geometria on Numerical 



Contractions 51 



Mr. Warington on the coloured FUms produced by Electro- 

 chemical Agency and by Heat 52 



Rev. D. WHliams on the Geology of Devon and Cornwall, 

 with reference to a Paper read before the Geological Society 



on December 4, 1839 59 



New Books : — MiUer's Treatise on Crystallography, — Transac- 

 tions of the Cambridge Philosophical Society, — Carpenter's 



Principles of General and Comparative Physiology 65 



Proceedings of the Royal Astronomical Society 72 



■ Linnaean Society 76 



New System of Postage 78 



Letter Barometer 79 



New Scientific Books 79 



Meteorological Observations for November 1839 79 



Meteorological Observations made at the Apartments of the 

 Royal Society by the Assistant Secretary, Mr, Roberton ; 

 by Mr. Thompson at the Garden of the Horticultural Society 

 at Chiswick, near London ; by Mr. Veall at Boston ; and by 

 Mr. Dunbar at Applegarth Manse, Dumfries-shire 80 



NUMBER CI.— FEBRUARY. 



Dr. Draper's Account of some Experiments made in the South 



ofVirginia, on the Light of the Sun ^ 81 



a2 



