X PREFACE. 



the improvement of your people has received the impulse of Your 

 Majesty's gracious sympathy and support. 



We desire to assure Your Majesty of our dutiful and affectionate 

 attachment to Your Majesty's person, and our loyalty to the 

 Throne. And we earnestly pray that Your Majesty may long be 

 spared to promote the happiness and receive the grateful homage 

 of Your Majesty's subjects. 



Signed on behalf of the Victoria Institute, this 22nd day of June, 

 1897, 



Gr. G. Stokes, PresiJent. 

 Halsbury, Vice-President. 

 Francis W. H. Petrie, Capt., 



Honorary Secretary. 

 8, Adelphi Terrace, London. 



REPLY, 



Whitehall, 



5 Jtdy, 1897. 

 Sir, 



I have had the honour to lay before the Queen the loyal and 

 dutiful Address of the President, Council and Members of the 

 Victoria Institute on the occasion of Her Majesty attaining the 

 sixtieth year of Her Reign, and I have to inform you that Her 

 Majesty was pleased to receive the same very graciously. 



I have the honour to be, 



Your obedient Servant, 



M. W. Ridley. 



This Twenty-Ninth Volume of the Journal of the 

 Transactions is a record of the various important questions, 

 treated in papers by competent authors, and carefully 

 investigated, and impartially discussed at meetings by 

 those who have studied the subjects to whose opinions 

 have been added the comments of others whom distance 

 has prevented attending the Institute's gatherings in person. 



The papers and discussions in this volume are upon the 

 following subjects : — " The Perception of Light," by Sir 

 G. G. Stokes, Bart., F.R.S., the President ; with remarks by 

 the Right Honourable Lord Halsbury, F.R.S. (Lord High 

 Chancellor), Sir H. Barkly, G.C.M.G., K.C.B., F.R.S., Sir 



