CONTENTS OF VOL. V. — FIFTH SERIES. Vll 



Page 

 Sir W. Thomson on Problems relating to Underground Tem- 

 perature. A Fragment 370 



Dr. L. Bleekrode on the Electric Conductivity and Electrolysis 



of Chemical Compounds 375 



Notices respecting New Books : — 



Die Potentialfunction und das Potential, ein Beitrag zur 



mathematischen Physik von B. Clausius 389 



Proceedings of the Geological Society : — 



Mr. A. B. "Wynne on the Physical Geology of the Upper 



Punjab 392 



Mr. J. S. Gardner's Description and Correlation of the 



Bournemouth Beds 393 



Mr. E. Daintree on certain Modes of Occurrence of Gold 



in Australia 394 



Mr. W. H. T. Power on the Geology of the Island of 



Mauritius and the adjacent Islets 394 



On the Pitch of a Tuning-fork in an Incompressible Fluid, by 



Felix Auerbach 395 



A Note on Experiments with Floating Magnets ; showing the 

 Motions and Arrangements in a Plane of freely moving 

 Bodies acted on by Forces of Attraction and Eepulsion, and 

 serving in the Study of the Directions and Motions of the 



.Lines of Magnetic Force, by Alfred M. Mayer 397 



On Sensations of Light and of Colour, in Direct and Indirect 



Vision, by E. Landolt and A. Charpentier 398 



On the Galvanic Polarization of Platinum in Water, by Dr. 

 F. Exner , 400 



NUMBEB XXXIII.— JUNE. 



Mr. E. Sabine on some Electrical Experiments with Crystalline 

 Selenium 401 



Prof. G. Quincke on the Edge- angle and Spread of Liquids on 

 Solid Bodies 415 



Mr. F. Guthrie on the Influence of Temperature on the Pas- 

 sage of Air through Capillary Tubes 433 



Dr. L. Bleekrode on the Electric Conductivity and Electrolysis 

 of Chemical Compounds . . 439 



Prof. Challis's Theoretical Explanations of the Actions of the 

 Eadiometer, the Otheoscope, and the Telephone 452 



Mr. G. J. Stoney on some remarkable Instances of Crookes's 

 Layers, or Compressed Strata of Polarized Gas, at ordinary 

 Atmospheric Tensions 457 



Messrs. J. A. Wanklyn and W. J. Cooper on Water-Analysis. 

 Determination of Cellulose and modified Cellulose in Drink- 

 ing- Water 464 



