Vi CONTENTS OF VOL. XX. FIFTH SERIES. 



Pago 



Lord Rayleigh on the Thermodynamic Efficiency of the Ther- 

 mopile 361 



Dr. J. Kerr on Electro -optic Action of a Charged Franklin's 

 Plate . 363 



Prof. O. Lodge on the Seat of the Electromotive Forces in a 

 Voltaic Cell. Theories of Wiedemann and of Helmholtz . . 372 



On a Differential Resistance-Thermometer, by T. C. Men- 

 denhall 384 



On the Determination Qf the Coefficients of Internal Friction, 

 by Walter Konig 387 



Note on the Transmission of Light by Wire-Gauze Screens, 

 by S. P. Langley 387 



NUMBER CXXVL— NOVEMBER. 



Prof. De Volson Wood on the Luminiferous iEther 389 



Prof. F. Himstedt on a Determination of the Ohm 417 



Mr. J. Larmor on the Molecular Theory of Galvanic Polariza- 

 tion ' 422 



Assist.-Prof. J. W. Clark on the Influence of Pressure on 

 certain cases of Electrical Conduction and Decomposition. 435 



Prof. H. Hennessy on the Winters of Great Britain and 

 Ireland, as influenced by the Gulf-Stream 439 



Prof. H. Hennessy on the Comparative Temperature of the 

 Northern and Southern Hemispheres of the Earth 442 



Mr. J. J. Hood on Retardation of Chemical Change 444 



Prof. C. Michie Smith on Atmospheric Electricity. 456 



Notices respecting New Books : — 



Prof. C. Winkler's Handbook of Technical Gas-analysis. 461 



On the Separation of Liquid Atmospheric Air into two diffe- 

 rent Liquids, by S. Wroblewski 463 



On the Source of the Hydrogen occluded by Zinc Dust, by 

 Greville Williams ' 464 



On two new Types of Condensing Hygrometers, by M. G. 

 Sire * 468 



NUMBER CXXVIL— DECEMBER. 



Prof. O. Reynolds on the Dilatancy of Media composed of 



Rigid Particles in Contact. (PlateX.) 469 



Mr. G. Gladstone on the Refraction of Fluorine 481 



Mr. T. Gray on Measurements of the Intensity of the Hori- 

 zontal Component of the Earth's Magnetic Eield made in 

 the Physical Laboratory of the University of Glasgow. 

 (Plate XL) * ' 484 



