Report of the Committee on Colour-Vision. 373 

 " Examination by Daylight (Cards). 



In conducting the examination by daylight the examiner 

 should do it in three ways : — 



"1. The cards should be mixed up. The examiner should 

 then hold up each card separately, and ask the candidate 

 to name the colour ; and if the candidate does so without 

 hesitation, he is to be regarded as having passed the 

 daylight test. 



" 2. If the candidate hesitates in any of his answers so as to 

 raise a doubt in the mind of the examiner as to his ability 

 to readily distinguish colours, the examiner should put 

 all the cards on the table and require the candidate to 

 select all cards of a colour or colours named by the 

 examiner. 



" 3. Having done that, they should all be mixed up again, 

 and the candidate should be required to sort the cards 

 into eight heaps, putting all of one colour into each heap. 



"4. The result of the examination should be noted and 

 recorded in each case. 



"Examination by Artificial Light. 



The room should be dark. 



The lamp lighted and placed in the lanthorn. 



The applicant should be seated or should stand so as to be 



opposite to the opening of the lanthorn ; and, at least, 15 



feet from the front of the lanthorn. 

 He should first of all see the light in the lanthorn without the 



interposition of any glass, and be asked if it appears to 



him to have any colour, and if so what colour ? 

 The slide with the ground glass should then be put into the 



opening at the front of the lanthorn which is nearest to 



the light, and the applicant asked the same question. 

 The slide with the ground glass is to be left in, and the slides 



with the coloured glasses placed one by one, and separately, 



in front, of it, and the candidate asked in each case to name 



the colour or tint. 

 The result of the examination should of course be noted and 



recorded in each case. 



"General. 



The cards and glasses against which a star is placed in the 

 list are what may be called confusion tints. The candidate 

 is not to be regarded as having ' failed ' if he miscalls 

 these tints, provided that he names all the others correctly. 

 But if, having named all the others correctly, he miscalls 

 these so far as to name the drab card, No. 6, as red, pink, 



