CONTENTS. Xlll 



Page 



4. Oa a Dynamical Top. By G. T. Walkbk, M.A 613 



5. *Suggestions as to Matter and Gravitation in Professor Hicks's Cellular 



Vortex Theory. By C. V. Burton, D.Sc G13 



6. *0n the Graphical Representation of the Partition of Numbers. By 



Major P. A. Macmahon, F R.S 613 



7. On a New Canon Arithmeticus. By Lt.-Col. Allan Cunningham, R.E. 613 



8. On Mersenne's Numbers. By Lt.-Col. Allan Cunningham, R.E 614 



9. Recent Developments of the Lunar Theory. By P. H. Cowell, M.A ... G14 



10. The Relation between the Morphological Symmetry and the Optical 



Symmetry of Crystals. By William Baelow 617 



11. On a Species of Tetrahedron the Volume of any member of which can be 

 determined without employing the proof of the proposition that Tetrahedra 

 on equal bases and having equal altitudes are equal, which depends on 



the Method of Limits. By Professor M. J. M. Hill, M.A., D.Sc, F.R.S. 619 



12. On Absolute and Relative Motion. By Professor J. D. Everett, F.R.S. 620 



13. On the Magnetic Field due to a Current in a Solenoid. By W. 11. 



Everett, B.A 620 



14. On the Law of Error in the Case of Correlated Variations. By S. II. 

 BuRBURY, F.R.S ." 621 



Department II. Meteorology. 



1. Probable Projection Lightning Flashes. By Eric Stuart Bruce, M.A. , 

 Oxou., F.R.Met.Soc. 624 



2. Report on Solar Radiation 625 



3. Report on Earth Tremors 625 



4. Reportsou Earthquakes in Japan 625 



5. On some Experiments made with Lord Kelvin's Portable Electrometer. 



By Arthur Schuster, F.R S 625 



6. On Indian Thunderstorms. By C. Michie Smith 626 



7 *0n the Zodiacal Light considered as an Atmospheric Phenomenon. By 



W. H. Wood 626 



8. *0n the Local Origin of the Aurora Borealis. By W. H. Wood 626 



9. Report on the Application of Photography to Meteorology 626 



10. Report on the Meteorological Observations on Ben Nevis 626 



MONDAY, SEPTEMBER 16. 



1. *A Discussion ' On the Objective Character of Combination Tones ' 626 



Notes on the Objective Existence of Combination Tones. By A. ^^^ 



RiJCKER, M.A., F.R.S 626 



2. *A Discussion ' On a New Practical Heat Standard.' Introduced by a 

 Paper by E. H. Griffiths, F.R.S 628 



3 On the Thermal Conductivities of Mixtures of Liquids. By Charles 

 H. Lees, D.Sc 628 



4. A Method of Comparing the Heats of Evaporation of Different Liquids 



at their Boiling Points By Professor W. Ramsay, Ph.D., F.R.S., and 

 Miss Dorothy Marshall, B.Sc 628 



5. tOn a Harmonic Analyser. By G. U. Yule 630 



