232 



The Numerical Registration of Colour. [Feb. 19, 



square image of the spectral colour patch, and the second image over 

 the latter. The same determinations are gone through as those just 

 determined. 



The following are the determinations of some of the coloured 

 glasses submitted to the Committee, recorded in this manner : 



The following are determinations of some coloured pigments in 

 electric light: 



