Proceedings. 



Ordinary Meeting, April 2nd, 1889. 



Professor OsBORNE REYNOLDS, M.A., LL.D., F.R.S., 

 President, in the Chair. 



Professor SCHUSTER described Lord Rayleigh's colour- 

 mixer, for testing colour sensations. There are many small 

 peculiarities in colour sensation different from colour blind- 

 ness, but certain more distinct peculiarities are rare and 

 seem to run in families. Persons affected by these greater 

 diversities agree quite well among themselves in their judg- 

 ment of a colour, and there is no intermediate class between 

 them and those having normal sight. 



Mr. Ralph Holmes, B.A., read a " Note on the Propa- 

 gation of Sound through an Atmosphere of Varying 

 Density." 



Dr. HODGKINSON read a third communication "On 

 Colour and its relation to the Structure of Coloured Bodies ; 

 being an Investigation into the Physical Cause of Colour in 

 natural and artificial bodies and the Nature of the Structure 

 producing it," describing the structures which cause the 

 silvery sheen of the herring and other fish, and those which 

 produce the distinctive colours offish. The author explained 

 how, on drying, these scaly structures give rise to the 

 changing colours of the dying dolphin. 



