IV 



June 15, 1893. 



Page 



On the Elasticity of a Crystal according to Boscovich. By the Lord 

 Kelvin, P.R.S 59 



Magnetic Qualities of Iron. By J. A. Ewing, M.A., F.R.S., Professor 

 of Mechanism and Applied Mechanics in the University of Cam- 

 bridge, and Miss Helen G. Klaassen, Lecturer in Physics, Newnham 

 College 75 



Polarisation of Platinum Electrodes in Sulphuric Acid. By James B. 

 Henderson, B.Sc 77 



On the Annual and Semi-annual Seismic Periods. By Charles Davison, 

 M.A., Mathematical Master at King Edward's High School, Bir- 

 mingham 82 



Electrical Interference Phenomena somewhat analogous to Newton's 

 Rings, but exhibited by Waves passing along Wires of which a part 

 differs from the rest. By Edwin H. Barton, B.Sc., " 1851 Exhibi- 

 tion " Science Scholar 85 



On Interference Phenomena in Electric Waves passing through different 

 Thicknesses of Electrolyte. By G. Udny Yule 96 



On the Ratio of the Specific Heats of the Paraffins and their Mono- 

 halogen Derivatives. By J. W. Capstick, M.Sc. (Viet.), B.A. (Camb.), 

 Scholar and Coutts-Trotter Student of Trinity College, Cambridge .... 101 



On Operators in Physical Mathematics. Part II. By Oliver Heavi- 

 side, F.R.S 105 



On a Failure of the Law in Photography that when the Products of the 

 Intensity of the Light acting and of the Time of Exposure are Equal, 

 Equal Amounts of Chemical Action will be produced. By Captain 

 W. de W. Abney, C.B., F.R.S 143 



On the Displacement of a Rigid Body in Space by Rotations. Pre- 

 liminary Note. By J. J. Walker, F.R.S 147 



On a Graphical Representation of the Twenty-seven Lines on a Cubic 

 Surface. By H. M. Taylor, M.A., Fellow of Trinity College, Cam- 

 bridge 148 



Further Observations on the Shoulder Girdle and Clavicular Arch in 

 the Ichthyosauria and Sauropterygia. By H. G. Seeley, F.R.S 149 



Researches on the Structure, Organisation, and Classification of the 

 Fossil Reptilia. Part VIII. On further Evidences of Deuterosaurus 

 and Rhopalodon from the Permian Rocks of Russia. By H. G. 

 Seeley, F.R.S 168 



The Menstruation of Semnopithecus entellus. By Walter Heape, M.A., 

 Balfour Student at the University of Cambridge 169 



Studies in the Morphology of Spore-producing Members. Part I. 

 Equisetinese and Lycopodineae. By F. O. Bower, D.Sc., F.R,S., Regius 

 Professor of Botany in the University of Glasgow 172 



On Megaladapis madagascariensis, an Extinct Gigantic Lemuroid from 

 Madagascar. By C. J. Forsyth Major, M.D., For. Cor. Zool. Soc. 

 Lond., &c 176 



Some of the Effects and Chemical Changes of Sugar injected into a 

 Vein. By Vaughan Harley, M.D., Teacher of Chemical Pathology, 

 University College, London, Grocer Research Scholar 179 



