CONTENTS OF VOL. XXVI 



(FIFTH SEEIES). 



NUMBER CLVI1L— JULY 1888. 



Page 

 Prof. A. Kimdt on the Indices of Refraction of the Metals . . 1 

 Mr. Herbert Tomliuson on a Theory concerning the Sudden 

 Loss of the Magnetic Properties of Iron and Nickel at 



certain Temperatures 18 



Mr. J. Joly on a Diffusion Photometer 26 



Mr. J. Joly on a Method of Determining the Specific Gravity 



of Small Quantities of Dense or Porous Bodies 29 



Mr. T. H. Blakesley on Magnetic Lag 34 



Mr. Charles V. Burton on Electromotive Eorces of Contact. . 43 

 Prof. Spencer Umfreville Pickering on Thermochemical Con- 

 stants 53 



Profs. W. E. Ayrton and J. Perry on the Governing of Elec- 

 tromotors 63 



Prof. S. P. Thompson on the Formulae of Bernoulli and of 



Haecker for the Lifting-power of Magnets 70 



Notices respecting New Books : — 



Watts's Dictionary of Chemistry 73 



Dr. T. Stevenson's Treatise on Alcohol, with Tables of 



Spirit Gravities 76 



On the Velocity of the Propagation of Sound, by MM. J. Violle 



and Th. Yautier 77 



On the Electrification of Metal Plates by Irradiation with 



Electrical Light, by W. Hallwachs 78 



The Benecke Prize in Philosophy 80 



NUMBER CLIX.— AUGUST. 



Prof. J. van't Hoff on the Eunction of Osmotic Pressure in 

 the Analogy between Solutions and Gases 81 



Messrs. Henry A. Rowland and Louis Byll on an Explanation 

 of the Action of a Magnet on Chemical Action 105 



