VI CONTENTS OF VOL. V. FIFTH SERIES. 



NUMBER XXXI.— APEIL. 



Page 

 Professors W. E. Ayrton and J. Perry on the Heat-conduc- 

 tivity of Stone, based on Fourier's Theorie de la Ohaleur. 



(Plates IX. & X.) . , 241 



Sir G. B. Airy on the Correction of the Compass in Iron Ships 



without use of a Fixed Mark. (Plate XL) 267 



Mr. S. P. Thompson on Permanent Plateau's Films 269 



Mr. EL F. Morley on Grove's Gas-Battery 272 



Mr. W. H. Preece on some Physical Points connected with the 



Telephone 281 



Prof. P. E. Chase on the Nebular Hypothesis. — VII. Undula- 

 tion 292 



Mr. S. T. Preston on the Bearing of the Kinetic Theory of 

 Gravitation on the Phenomena of "Cohesion" and "Che- 

 mical Action," together with the important connected In- 

 ferences regardingthe existenceof Stores of Motion in Space. 297 

 Notices respecting New Books : — 



Des Paratonnerres a Pointes, a Conducteurs et a Rac- 

 cordements Terrestres Multiples. Description detaillee 

 des Paratonnerres etablis sur 1'Hotel de Yille de 

 Bruxelles en 1865. Expose des Motifs des disposi- 

 tions adoptees par Melsens, Membre de l'Acad. Boy. 



de Belgique 311 



Proceedings of the Geological Society : — 



Prof. J. W. Judd on the Secondary Rocks of Scotland . . 313 

 On Galvanic Currents between Solutions of different degrees 

 of Concentration of the same Substance, and their Series of 



Tensions, by Dr. James Moser 317 



On the Extraction of Gallium, by MM. Lecoq de Boisbaudran 



and E. Jungfleisch 318 



On the Resistance of Fluids 320 



NUMBER XXXII.— MAT. 



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



Solid Bodies. (Plate XII.) 321 



G. W. von Tunzelmann on the Production of Thermoelectric 



Currents in Wires subjected to Mechanical Strain 339 



Prof. Helmholtz on Galvanic Currents occasioned by Differ- 

 ences of Concentration — Inferences from the Mechanical 



Theory of Heat 348 



Mr. R. Mallet on the Rate of Earthquake- wave Transit .... 358 

 Prof. P. E. Chase on the Nebular Hypothesis.— VIII. Criteria. 362 

 Prof. R. B. Clifton on the Difference of Potential produced 

 bv the Contact of different Substances , 367 



