248 



Prof. G. H. Darwin. 



May 2, 1901. 



Sir WILLIAM HUGGINS, K.C.B., D.C.L., President, in the Chair. 



A List of the Presents received was laid on the table, and thanks 

 ordered for them. 



In pursuance of the Statutes, the names of the Candidates recom- 

 mended for election into the Society were read, as follows : — 



Alcock, Professor Alfred William, 

 M.B. 



Dyson, Frank Watson, M.A. 

 Evans, Arthur John, M.A. 

 Gregory, Professor John Walter, 

 D.Sc. 



Jackson, Henry Bradwarcline, 



Captain, E.N. 

 Macdonald, Hector Munro, M.A. 

 Mansergh, James, M.Inst.C.E. 



Martin, Prof. Charles James, M.B. 

 Ross, Ronald, Major (I.M.S., re- 

 tired). 



Schlich, Professor William, CLE. 

 Smithells, Professor Arthur, B.Sc. 

 Thomas, Michael R. Oldfield, F.Z.S. 

 Watson, William, B.Sc. 

 Whetham, William C. Dampier, 

 M.A. 



Woodward, Arthur Smith, F.G.S. 



The following Papers were read : — 



I. " On the Variation in Gradation of a Developed Photographic 

 Image when impressed by Monochromatic Light of different 

 Wave-lengths." By Sir W. de W. Abney, K.C.B., F.R.S. 



II. " Ellipsoidal Harmonic Analysis." By G. H. Darwin, F.R.S. 



III. " On the Small Vertical Movements of a Stone laid on the Surface 

 of the Ground." By Horace Darwin. Communicated by 

 Clement Reid, F.R.S. 



" Ellipsoidal Harmonic Analysis." By G. H. Darwin, F.R.S., 

 Plumian Professor and Fellow of Trinity College in the 

 University of Cambridge. Received March 23, — Read May 2, 

 1901. 



(Abstract.) 



Lame's functions have been used in many investigations, but the 

 form in which they have been presented has always been such as to 

 render numerical calculation so difficult as to be practically impossible. 

 The object of this paper is to remove the imperfection in question by 



