i8§5-] 
Testing for Colour-blindness. 
411 
not permitted to present themselves for the further examina 
tions in navigation and in seamanship. In the event, how- 
ever, of either a mate or master having already received a 
certificate of a lower grade, and presenting himself for one 
of a higher grade, and then failing to satisfy the examiner 
of his ability to distinguish colours, the higher grade certifi- 
cate has been granted, with a statement written across it 
that “ the holder has failed to pass the examination in 
colours.” This has, no doubt, in individual cases operated pre- 
judicially; it has prevented incompetent mates or masters 
from obtaining employment, but it is only right and just 
that shipowners should be in a position to protect themselves. 
No case of hardship has, however, come to the knowledge 
of the Board : furthermore, to guard against injustice or a 
hasty judgment on the part of the examiner, a candidate 
may, on the expiration of three months from his first ex- 
amination, apply to be re-examined for a second and third 
time, and by a later order he can obtain the permission of 
the Board of Trade to be again tested in colours for the 
fourth and last time. 
By the extension of the colour-test to all persons, any 
man or boy about to enter the Mercantile Marine can satisfy 
himself and his friends of his ability to distinguish the 
colours of the flags and lights in use on board ship. These 
optional examinations have also been the means of preventing 
those who are unable to name colours from taking to the sea 
at all as a means of livelihood. 
It is a matter of considerable regret that the colour-test 
has not been made obligatory upon pilots and men on the 
“ look out,” as well as upon masters and mates. Pilots 
claim the right to navigate all ships as soon as they near 
our coasts, and it is of the very gravest importance that 
they should make no mistake as to the lights displayed by 
other ships. This omission is entirely owing to a divided 
authority, the pilot service being exclusively under the control 
of the Trinity House, a body alleged to be somewhat 
addicted to placing obstacles in the way of scientific 
progress. 
The mode of conducting the colour-test examination is of a 
threefold nature— by coloured cards, wools, and glasses. The 
examiners are supplied with selected boxes of each of these, 
and the examination commences with the cards, the most 
important daylight test being red, gieen, and black : if the 
candidate is able to distinguish and name the colour of each 
it is sufficient, and he obtains his ceitificate. I he standaid 
red and green glasses are of the same colours as the “port” 
