^92 SECTIONAL TRANSACTIONS.— I, J, 



The facts of colour-blindness are totally opposed to any theory which assumed 

 elementary sensations of which the other colour sensations are compounded. 

 A theory of colour vision should explain how 50 per cent, of dangerously colour- 

 blind can pass the wool test, the varying size of the monochromatic divisions 

 in the spectrum with different degrees of colour perception, why the trichromic 

 mark out about half the normal number of monochromatic divisions in the 

 spectrum, designate yellow as red-green, and have an increased simultaneous 

 colour contrast ? When there are three definite colour sensations how can colour- 

 blindness be explained? When a colour-blind person is tested by making him 

 match a white with a mixture of red, green, and violet, he may put too much 

 red in the mixture, and then too much green, and also agree with the normal 

 match ; he may only agree with the normal match when the comparison white 

 light is increased in some cases and in others diminished in intensity. Cases 

 of shortening of the red end of the spectrum without defective colour discrimina- 

 tion require to be explained. A man may also make an anomalous equation, 

 putting too much green or too much red in the mixture, without any evidence 

 of colour-blindness. 



13. Dr. F. W. Edridge-Green, C.B.E. — The Necessitxj for a Standard 



of White. 



On account of the varying physical character of white light, even of daylight, 

 which varies at different times of the day, and still more with light from 

 artificial sources, any record for physiological purposes should contain a 

 reference to the source of white light, which sliould be used for purposes of 

 comparison and which can be reproduced by another observer. Very misleading 

 results are obtained by the omission of a comparison light. For instance, the 

 table of complementary colours given by Helmholtz was made without any 

 comparison white light ; his table does not agree with that of other observers. 



Tuesday, September 12. 



14. Dr. P. .M. ToLMiE. — The Cytology of the Blood and the Source, 



Drvelopment and Function of Sonic of the Corpuscles. 



15. Dr. J. H. Burn. — The Physiology of Sweating. 



After denervation of the limb of a cat, in which either the whole nerve 

 supply or the sympathetic fibres only are involved, changes taking place in the 

 response of the sweat glandsi to pilocarpine are accompanied by parallel changes 

 taking place in the dilatation of the limb in response to histamine injected 

 intravenously. The suggestion arising is that the activity of the sweat glands, 

 when stimulated by pilocarpine, depends on the local capillary tone, a tone 

 independent of the arterial tone in the limb, and that the maintenance of 

 this tone is dependent amongst other things on the integrity of the sensory 

 nerves. 



16. Prof. W. D. Halliburton, F.R.S. — Lecture on Our Bones and 



Teeth . 



SECTION J.-PSYCHOLOGY. 



(For references to the publication elsewhere of communications entered in the 

 following list of transactions, see pp. 409-10.) 



Thursday, September 7. 



1. Dr. C. S. Myers. — Industrial Psychology and the Efficiency 

 Engineer. 



