﻿CONTENTS OF VOL. XXXVIII. 



(FIFTH SERIES). 



NUMBER CCXXX.— JULY 1894. 



Page 



Mr. W. Sutherland on the Attraction of Unlike Molecules. — 

 I. The Diffusion of G-ases 1 



Mr. Carl Barus on Coloured Cloudy Condensation, as Depend- 

 ing on the Temperature and the Dust-contents of the Air. 

 (Plate Y.) 19 



Dr. W. Peddie on Torsional Oscillations of Wires 36 



Dr. Charles V. Burton on the Mechanism of Electrical Con- 

 duction. — Part I. Conduction in Metals 55 



Mr. W. B. Croft : Some Observations on Diffraction. (Plates 

 I -IV.) 70 



Dr. L. Bleekrode on some Experiments with Carbon Dioxide 

 in the Solid State 81 



Prof. R. Threlfall on an Approximate Method of finding the 

 Forces acting in Magnetic Circuits 89 



Prof. O. Henrici on a New Harmonic Analyser 110 



Mr. Archibald Sharp on an Harmonic Analyser, giving 

 Direct Readings of the Amplitude and Epoch of the various 

 constituent Simple Harmonic Terms 121 



Prof. Perry : Remarks on Prof. Henrici's Paper on a new 

 Harmonic Analyser 125 



Rev. O. Fisher on the Effect of Sphericity in Calculating the 

 Position of a Level of no Straiu within a Solid Earth, and 

 on the Contraction Theory of Mountains 131 



Mr. E. L. O. Wadsworth on an Improved Form of Littrow 

 Spectroscope. (Plate VI.) 137 



Dr. Alexander Macfarlane on the Geometrical Interpretation 

 of log Vq 143 



Dr. John Kerr on a Fundamental Question in Electro-Optics. 144 



Notices respecting New Books : — 



Mr. O. Heaviside's Electromagnetic Theory 146 



Proceedings of the Geological Society : — 



Mr. J. Parkinson on Leigh Creek Jurassic Coal-Measures 

 of South Australia ; and on the Physical and Chemical 

 Geology of the Interior of Australia 157 



On the Dependence of the Photoelectric Current on the 

 Position of the Plane of Polarization of the Exciting Light 



