PROCEEDINGS OF 

 THE ROYAL SOCIETY. 



vol. lxxi. No. 474. 



CONTENTS. 



PAGE 



A Note on a Forni of Magnetic Detector for Hertzian Waves, adapted for 

 Quantitative Work. By Dr. J. A. Fleming, F.E.S., Professor of Elec- 

 trical Engineering in University College, London 398 



A New Form of Self -restoring Coherer. By Sir Oliyee Lodge, F.E.S. . 402 



On Central American Earthquakes, particularly the Earthquake of 1838. By 



Admiral Sir John Daleymple Hay, Bart., G-.C.B., F.E.S. . . . 403 



The Emanations of Eadium. By Sir William Ceookes, F.E.S. . . . 405 



Bakeeian Lectuee. — On the Constitution of the Copper-Tin Series of Alloys. 



By C. T. Heycock and F. H. Neville. (Abstract) .... 409 



On the Formation of Barrier Eeefs and of the different Types of Atolls. By 



Alexander Agassiz, For. Mem. E.S 412 



The Electrical Conductivity imparted to a Vacuum by Hot Conductors. By 

 O. W. Eichabdson, B.A., B.Sc, Fellow of Trinity College, Cambridge. 

 Communicated by J. J. Thomson, F.E.S. (Abstract) .... 415 



On a New Series of Lines in the Spectrum of Magnesium. By A. Fowler. 

 A.E.C.Sc, F.E.A.S., Assistant Professor of Physics, Eoyal College of 

 Science, South Kensington. Communicated by H. L. Callendae, F.E.S. 419 



An Attempt to Estimate the Eelative Amounts of Krypton and of Xenon in 



Atmospheric Air. By Sir William Eamsay, K.C.B., F.E.S. . . .421 



Some Physical Properties of Nickel Carbonyl. By James Dewae, M.A., 

 Sc.D., LL.D., F.E.S., Jacksonian Professor in the University of Cam- 

 bridge, and Humpheey Owen Jones, M.A., Fellow of Clare College, 

 Jacksonian Demonstrator in the University of Cambridge. . . . 427 



An Enquiry into the Variation of Angles observed in Crystals, especially of 

 Potassium- Alum and Ammonium- Alum. By Professor H. A. Muses, 

 M.A., D.Sc, F.E.S. (Abstract) 439 



On the Dependence of the Eefractive Index of Oases on Temperature. By 

 George W. Walker, M.A. Communicated by Professor J. J. Thomson, 

 F.E.S. (Abstract) 441 



On the Evolution of the Proboscidea. By C. W. Andrews, D.Sc. Com- 

 municated by Professor E. Eay Lankester, F.E.S. (Abstract) . . 443 



A Comparative Study of the Grrey and White Matter of the Motor Cell 

 Groups, and of the Spinal Accessory Nerve, in the Spinal Cord of the 

 Porpoise (Phoccena communis). By David Hepburn, M.D., and David 

 Waterston, M.A., M.D. Communicated by Sir Wm. Ttjrneb, F.E.S. 

 (Abstract) . . . 444 



Price One Shilling and Sixptyce 



April 30, 1903. 



