I(i2 COLOR-BLINDNESS IN ITS EKLATION TO 



•while directing our researches especially to this point, not a few have 

 been painters and tailors. 



But such disregard to the subject of colors is no longer permitted in 

 occupations where colored signals are employed and where human life 

 may depend upon the manner in which the signal is or is not understood, 

 as on railways and at sea. 



A great number of color blind are to be found employed in almost 

 every position on railways, without the defect in their chromatic sense 

 being suspected by themselves or others. Nay, more, a number of them, 

 far from being willing to acknowledge, even after the examination, the 

 existence of such a defect, urgently demand a new trial, even six or 

 seven, offering all kinds of pretexts to account for their repeated failures. 

 They all agree in declaring that they have excellent sight; that they 

 have never had the least diificulty in distinguishing signals, though they 

 have been employed for a long time and in the most important positions, 

 that for instance of engineer, and had never made the slightest mistake; 

 that the engineer is never the only one whose duty it is to watch the 

 signals. He has always near him a fireman, and in his neighborhood 

 an assistant engineer, a greaser, etc., who come to his aid at critical 

 moments. That must be a very rare case where all the officials are 

 affected with color-blindness. 



Looking practically at the fact mentioned and the explanation given, 

 it might be imagined probably that color-blindness, although a subject 

 of scientific interest, could not possess any possible practical interest. 

 At least, it might be believed that all the stir which has been made in 

 our country about color-blindness amongst railway employes was founded 

 upon nothing real. Since it is proved (it may perhaps be urged) that the 

 color-blind have long been employed on railways and the defect never 

 remarked, without any accident or even inconvenience resulting from 

 it, and finally since they can really learn to distinguish signals, although 

 otherwise than by colors, their kind of blindness should not legitimately 

 give rise to any preventive measures whatsoever. And doubtless a 

 great many still reason in this manner. 



We will not dwell here upon what experience has or has not proved 

 with regard to this in our country. The fact is certain that colorblind- 

 ness in other countries has caused numerous and serious accidents. And 

 even though experience should not have proved it in an absolute manner, 

 it would not be the less evident that in such cases no one has the right 

 to await a new experience of this kind before proceeding from words 

 to acts, inasmuch as it can be demonstrated that, in spite of the many 

 circumstances aiding the color-blind to obey signals, all danger is not 

 averted, and uncertainty still remains. Now, this is not difScult to 

 prove, for neither the fact that color-blind individuals have been long 

 employed on railways without causing accidents, or without the discov- 

 ery of the defect, nor the circumstances we have cited to explain this 

 fact, furnish the slightest ground for security. 



