86 
Proceedings of the Royal Society of Edinburgh. [Sess. 
by Board of Trade examination, and also by R.A.F. Has a brother with 
defective colour vision. 19 patches. 
16. This observer was ISTo. 71 of the colour-perception spectrometer test. He obtained 
8 patches by that test instead of the normal 15. Called green a “dirty 
yellow,” and had the other colour names completely mixed up. Could not dis- 
tinguish the blue and green tramcars by their colour until they were directly 
opposite. In the four years that have elapsed since his former examina- 
tion he has improved considerably in using the colour names. 22 patches. 
17. 1^0. 211 of the microscope test. In the bead test he had everything wrong 
except two blues. In the green hole he put nothing except pale pink. 
When shown spectrum colours he called green “ yellow,” and yellowish 
green “ reddish yellow.” Did not think there was anything wrong with 
his colour vision, even after the tests were finished. 31 patches. 
18. No. 599 in microscope test. Knew he was “ partially colour blind,” but said 
he had no difficulty in recognising strong colours. Thought his memory 
for colours was bad. In bead test put green in red hole, and pink, pale 
pink, and dark pink in green. 32 patches. 
19. No. 579 in microscope test. Put green in red hole, and red, dark pink, and pale 
pink in green hole in bead test. 39 patches. 
20. No. 634 in microscope test. Peacock-blue in green and other slight errors in 
bead test. 13 patches. It is somewhat surprising that he does so well in 
the bead test with such a small number of patches. 
21. Came as the result of a dispute about the colour of an object. In bead test put 
gold and greenish yellow into green. 20 patches. 
22. No. 246 of the microscope test. Normal in bead test; but when shown a 
spectrum, called green with a trace of yellow in it “yellow.” 19 patches. 
23. This observer was a student at a school of navigation. His first Board of Trade 
examination was inconclusive ; the results of his second were referred to 
London for decision, and he was failed. He appealed, went to London 
for re-examination, and was failed again. He himself was very positive 
that his colour vision was good. 
In the bead test the very first step he took was to put peacock-blue into 
green. Everything else was normal. When shown spectrum colours he 
called orange “ red,” and both yellowish green and green with a slight tint of 
yellow “ yellow,” the latter two in a hesitating manner. He had the other 
spectrum colours right. His mean red-green reading in the microscope test 
was 10*9. 21 patches. 
24. No. 486 in microscope test. Said he had difficulties with purples and blues. 
Almost normal in bead test. 28 patches. 
25. This was a foreigner, who, I noticed in the laboratory, had the colour names 
completely wrong, although his knowledge of English was excellent. When 
examined by the bead test, he put dark pink in blue, left out greenish 
yellow, and put in the other beads in a hesitating manner. His performance 
under examination was not bad enough to account for his colour terminology, 
which doubtless was partly due to English not being his native language. 
42 patches. 
