CONTENTS OF VOL. XLIV. 



(FIFTH SEELES). 



NUMBER CCLXVL— JULY 1897. 



Page 

 Mr. W. C. Darnpier Whetham on the Ionizing Power o£ 

 Solvents , 1 



Dr. Yladimir Novak on the Specific Electric Conductivities 

 and Freezing-points of Solutions of Water in Formic Acid. 9 



Messrs. W. Craig Henderson and J. Henry's Experiments on 

 the Motion of the iEther in an Electromagnetic Field .... 20 



Messrs. T. A. Garrett and William Lucas on a INickel Stress 

 Telephone 26 



Lord Bayleigh on the Incidence of Aerial and Electric Waves 

 upon Small Obstacles in the form of Ellipsoids or Elliptic 

 Cylinders, and on the Passage of Electric Waves through 

 a circular Aperture in a Conducting Screen 28 



Mr. W. Sutherland on Thermal Transpiration and Radio- 

 meter Motion 52 



Dr. P. Zeeman on Doublets and Triplets in the Spectrum 

 produced by External Magnetic Forces 55 



Mr. W. A. Price on Alternating Currents in Concentric Cables 61 



Mr. Eollo Appleyard on the Formation of Mercury Films 

 by an Electrical Process 74 



Mr. J.Eose-Innes on the Isothermals of Isopentane. (Plate I.) 76 



Prof. E. L. 0. Wadsworth on the Conditions which Determine 

 the Ultimate Optical Efficiency of Methods for Observing 

 Small Eotations, and on a Simple Method of Doubling the 

 Accuracy of the Mirror and Scale Method 83 



Dr. Cr. Johnstone Stoney on the Proof of a Theorem in 

 Wave-motion • • 98 



Dr. J. Carruthers Beattie on the Electrification of Air by 

 Uranium and its Compounds. With a Note by Lord Kelvin 102 



Mr. Albert A. Michelson on Eadiation in a Magnetic Field . 109 



Mr. W. Watson on an Instrument for the Comparison of 

 Thermometers ; 116 



