VI CONTENTS OF VOL. XXXV. FOURTH SERIES. 



Page 

 On the Passage of Electrical Currents through Incandescent 



Ga.«es, by M. E. Becquerel 319 



On the Woodwardite of Cornwall, by M. F. Pisani 320 



Dialysis of Induction-currents, by M. Bouchotte 322 



NUMBER CCXXXVIIL— MAY. 



Mr. F. C. Webb on "Inductive Circuits," or the Application of 

 Ohm's Law to Problems of Electrostatics -. 325 



Prof. F. Guthrie on a new form of Voltameter and Voltastat . . 334 



M. R. Riihlmann on the Alteration produced by Heat in the 

 Velocity of Propagation of Light in Water 336 



Mr. J. C. Maxwell on Mr. Grove's "Experiment in Magneto- 

 electric Induction." In a Letter to W. R. Grove, F.R.S. . . 360 



Mr. J. Croll on Geological Time, and the probable Date of the 

 Glacial nnd the Upper Miocene Period 363 



Mr. P. E. Chase on the Specific Magnetism of Iron 384 



Proceedings of the Royal Society : — 



Mr. J. C. Maxwell on Governors . , 385 



Proceedings of the Geological Society : — 



Mr. J. Prestwich on the Structure of the Crag-beds of 

 Norfolk and Suffolk, with some observations on their 

 Organic remains 398 



On Stellar Spectra, by Father Secchi 400 



On an Optical Phenomenon, by Professor Robert Ball, Esq. . . 404 



On an Apparatus for proving that the Electric Spark does not 

 pass through an Absolute Vacuum, by MM. Alvergniat. . . . 404 



NUMBER CCXXXIX.— JUNE. 



Prof. R. Clausius on the Second Fundamental Theorem of the 

 Mechanical Theory of Heat „ 405 



Mr. C. W. Merrifield on the Application of a Graphical Me- 

 thod to the Problem of Rectilinear Motion in a Homoge- 

 neous Resisting Medium 420 



M. Berthelot on a New Thermometer for measuring Tempera- 

 tures above the Boiling-point of Mercury. (With a Plate.) 423 



Prof. C. V. Zenger on the Periodic Change of Climate caused 

 by the Moon 433 



