

1889.] Spectrum of the Rings of Saturn. 315 



February 7, 1889. 

 Professor G. G-. STOKES, D.C.L., President, in the Chair. 



The Presents received were laid on the table, and thanks ordered 

 for them. 



The following Papers were read : 



I. " Second Series of Results of the Harmonic Analysis of 

 Tidal Observations." Collected by G. H. DARWIN, LL.D., 

 F.R.S., Fellow of Trinity College and Plumian Professor 

 in the University of Cambridge. Received January 18, 



1889. 



[Publication deferred.] 



II. " The Principles of training Rivers through Tidal Estuaries, 

 as illustrated by Investigations into the Methods of 

 improving the Navigation Channels of the Estuary of the 

 Seine." By LEVESON FRANCIS VERNON-HARCOURT, M.A., 

 M.lnst.C.E. Communicated by A. G. VERNON-HARCOURT, 

 F.R.S. Received January 19, 1889. 



[Publication deferred.] 



III. " Note on the Spectrum of the Rings of Saturn." By J. 

 NORMAN LOCKYER, F.R.S. Received and read February 7, 



1889. 



The acknowledged meteoritic constitution of the rings of Saturn 

 rendered it important to obtain a photograph of their spectrum, in 

 order that it might he determined whether collisions there were of 

 sufficient intensity to produce incandescent vapours. It has long 

 been known that the rings appear much -more luminous than the 

 planet, and the magnificent photographs obtained by the Brothers 

 Henry show that this is truer for the blue light than for the visual 

 rays. 



The weather has been so bad that only one long exposure photo- 

 graph has been taken. Although the instrument was not in perfect 



VOL. XLV. 



