r iii ] 



CONTENTS. 



(A) 

 VOL. 211. 



List of Illustrations page v 



Advertisement vii 



I. On the Absolute E.rpi vision of Mercury. By HUGH L. CALLEN!>AR, M.A., LL.D., 



F.ti.X., Professor of Physics >tt the Imperial College of Science and Tech- 

 nology, S.W., and HERBERT Moss, RSc., A.R.C.S., Demonstrator of Physics 

 at the Imperial College of Science and Technology, London, S. W. . page 1 



II. Tin' Effect of Pressure upon Arc Spectra. No. 3. Silver, X 4000 to X 4600. 



No. 4. -Gold. By W. GEOFFREY DUFFIELD, D.Sc., Honorary Research 

 Fellow in Physics in the University of Manchester. Communicated by 

 ARTHUR SCHUSTER, F.RS. 33 



III. Memoir on the Theory of the Partitions of Numbers. Part V. Partitions 



in Two-dimensional Space. By Major P. A. MAcMAHOtf, R.A., D.Sc., 

 F.RS. 75 



IV. Sturm- Liouville Series of Normal Functions in the Theory of Integral 



Equations. By J. MERCER, M.A. (Cantab.), D.Sc. (Live)-pool), Fellow of 

 Trinity College, Cambridge. Communicated by Prof. A. R. FORSYTH, Sc.D., 

 LL.D., F.RS. Ill 



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