CONTENTS OF VOL. VII. 



(FIFTH SEEIES). 



NtfMBEE XL.— JANUARY 1879. 



Page 

 M. W. Beetz on the Excitation of Electricity at the Contact of 



Solids and G-ases 1 



Mr. G. F. Fitzgerald on the Mechanical Theory of Crookes's 



Force 15 



Mr. W. H. Preece on the Electric Light 29 



Prof. H. F. Weber on the Inductions that occur in the Tele- 

 phone 34 



Mr. W. Baily on Starch and Unannealed Glass under the 



Polariscope. (Plates I.-IV.) 39 



M. J. Frohlich on a new Proposition in the Theory of Diffrac- 

 tion, and its Application 51 



Mr. W. Crookes on the Illumination of Lines of Molecular 



Pressure, and the Trajectory of Molecules 57 



Notices respecting New Books : — 



Mr. H. F. Blanford : I. Eeport on the Administration of 

 the Meteorological Department of the Government of 

 India in 1876-77; II. Eeport on the Meteorology 

 of India in 1876 ; III. Indian Meteorological Me- 

 moirs 64 



Proceedings of the Geological Society : — 



Mr. C. E. Austin on the Distribution of Boulders by other 



Agencies than that of Icebergs 66 



Prof. T. G. Bonney and Mr. F. T. S. Houghton on some 



Mica-Traps from the Kendal and Sedbergh Districts . . 66 

 Mr. W. A. E. Ussher's Pleistocene Notes on the Cornish 



Coast near Padstow 66 



Mr. W. A. E. Ussher on the Pleistocene History of Corn- 

 wall 67 



On the Figure of the Planet Mars. Letter from Professor H. 



Hennessy 67 



On a new Phenomenon of Static Electricity, by E. Duter .... 69 

 New Observations on the Part played by Pressure in Che- 

 mical Phenomena, bv M. Berthelot 70 



