﻿CONTENTS OF VOL. XII. SIXTH SERIES. Til 



Page 



Dr. G. von Xeumayer's Anleitung zu Wi>-fMischaftlichen 

 Beobacbtungen auf Reisen 526 



S. Yogi's Die Physik Roger Bacos .^ 527 



Jamin's Cours de Physique de l'Ecole Polytechnique, 

 Troisieme Supplement par Prof. Bouty 527 



Drs. Millikan and Gale's First Course in Physics 528 



G. de Metz's La Double Refraction accidentelle dans 



les Liquides 528 



Proceedings of the Geological Society : — 



Dr. Maria Ogilvie Gordon on Interference-Phenomena in 

 the Alps 529 



Mr. W. R. Baldwin- Wiseman on the Influence of 

 Pressure and Porosity on the Motion of Sub-Surface 



Water \ , 531 



Intelligence and Miscellaneous Articles : — 



Atomic Conductivities of the Ions, by P. Blackmail .... 532 



NUMBER LXXIL— DECEMBER. 



Mr. W. A. Scoble on the Strength and Behaviour of Ductile 

 Materials under Combined Stress 533 



Dr. H. W. Malcolm on Double Refraction in Colloids produced 

 by Electric Endosmose 54S 



Dr. G. Bakker on the Theory of Surface Forces 557 



Dr. S. Tolver Preston on Certain Questions connected with 

 Astronomical Physics 570 



Prof. E. H. Barton and Mr. J. Penzer on Simultaneous Vibra- 

 tion-Curves of String and Air photographically obtained 

 from a Monochord. (Plate XIX.) 576 



Mr. G. A. Schott : A Kinematical Explanation of Groups of 

 Spectrum Lines with Constant Erequencv-Difference .... 579 



Dr. W. Marshall Watts and Mr. H. M. Wilkinson on the 

 " Swan " Spectrum 581 



Prof. R. W. Wood on the Intensification of Glass Diffraction 

 Gratings, and the Diffraction Process of Colour Photography. 5s5 



Prof. J. A. Fleming on the Electric Radiation from Bent 

 Antenna). (Plates XVII. & XVIII.) 588 



Dr. R. S. Willows on the Electrical Resistance of Alloys . . 604 



Xotices respecting Xew Books : — 



W. H. Wheeler's Practical Manual of Tides and Waves . 610 

 Dr. C. Doelter's Pedogenesis 610 



Index , 611 



