CONTENTS of N° 253.— Fifth Series. 



LII. Therrno-Electric Interpolation Formulae. By Prof. Silas 

 W. Holman . . page 465 



LIII. Notes on the Electromagnetic Theory of Moving Charges. 

 By W. B. Moeton, B.A 488 



LIV. On a Simple Apparatus for determining the Thermal Con- 

 ductivities of Cements and other Substances used in the Arts. By 

 Chaeles H. Lees, D.Sc, and J. D. Choelton, B.Sc, Joule Scholar 

 of the Eoyal Society 495 



LV. On the Eelation between the Brightness of an Object and 

 that of its Image. By W. T. A. Emtage, M.A 504 



LVI. Adjustment of the Kelvin Bridge. By Eollo Appleyaed 506 



LYII. The Effect of "Wave Eorm on the Alternate Current Arc. 

 By Julius Eeith, 1851 Exhibition Scholar 507 



LYIII. On the Calculation of the Conductivity of Mixtures of 

 Electrolytes having a common Ion. By Douglas M c Intosh, 

 Physical Laboratory, Dalhousie College, Halifax, N.S. 510 



LIX. Notices respecting New Books : — Dr. H. du Bois's The 

 Magnetic Circuit ; Heemann Geassman^'s Ausdehnungslehre ; 

 Mr. A. H. Baekee's Graphical Calculus 517-519 



LX. Proceedings of Learned Societies : — 



Geological Society : — Mr. G. W. Lamplugh on the Speeton 

 Series in Yorkshire and Lincolnshire ; Eev. Edwin Hill on 

 Transported Boulder Clay ; Dr. Henet Hicks on the Morte 

 Slates and Associated Beds in North Devon and West 

 Somerset ; Prof. T. W. Edgewoeth David on Evidences 

 of Glacial Action in Australia in Permo-Carboniferous Time ; 

 Mr. Aleeed Haekee on certain Granophyres, modified by 

 the Incorporation of Gabbro Fragments, in Strath (Skye) ; 

 Prof. E. Hull on the Geology of the Nile Yalley, and on 

 the Evidence of the greater Volume of that Eiver at a former 

 Period 519-524 



LXI. Intelligence and Miscellaneous Articles : — 



On the Diffusion of Metals, by Prof. W. C. Eoberts-Austen . . 524 



Eontgen Eays not present in Sunlight, by M. Carey Lea .... 528 



On a new Areometer, by L.-N. Yandervyver 530 



Index 532 



With Titlepage, Contents, &c. 



*&* It is requested that all Communications for this Work may be addressed, 

 post-paid, to the Care of Messrs. Taylor and Francis, Printing Office, Red 

 Lion Court, Fleet Street, London. 



