Color Blindness.

Manufacturer and Builder 8, 1893

In a recently-published report issued by the Marine Department of the British Board of Trade, some curious and valuable information is given with regard to the proportion of color blindness in the mercantile marine of that country. The number of candidates who presented themselves for examination for certificates as masters and mates during the previous year, was 4,688, of whom 31 were rejected because of their inability to distinguish colors. Of this number, 21 insisted that red was green, and others asserted that red was some other color than either red or green — usually drab. Candidates to the number of 201 mistook drab for green, 64 mistook drab for pink, and others asserted that it was white or yellow or red. As for pink, 106 persons said it was green, 32 that it was drab, 17 that it red, and 34 that it was something else. With regard to green, 32 averred that it was white, 42 that it was pink, 33 that it was drab, and 28 that it was red. It appears, however, as before stated, that only 31 were entirely disqualified, as their inability to distinguish colors was so great that it would probably lead to disaster on the high seas, while in the majority of instances the defect was a particular one, and consisted rather in the inability to distinguish one or two colors than in the inability to distinguish all colors, save black and white.

At the same time the figures show how common color blindness is. No exhaustive experiments have ever been carried out with the view of ascertaining the proportion of sufferers from the defect, but it has been asserted on good authority that one individual in thirty is partially, and one individual in fifty, is wholly unable to distinguish between colors. The defect is believed to be more common among men than among women, one writer on the subject holding that superior color perception on the part of the female has been transmitted and intensified. Another adds: "If the condition is an inherited one, then possibly evolutionists may be able to explain the female superiority in this respect by reference to farback ages when selection of their partners was, theoretically, a marked duty and privilege of the weaker sex." It may be remarked that savages of both sexes seem to be more favorably endowed than civilized man in regard to the color sense. Their fine perception of color is manifest in their war paint, their crowns of brilliant flowers, and still more brilliant birds' feathers, their brightly-stained skins and parti-colored dresses, all in marked contrast to the more civilized dwellers in the temperate zones.

Color blindness is an important question, not as bearing on navigation alone, but upon every kind of employment in which the security of life and property depends upon accuracy in distinguishing signals. Defective eyesight has been responsible for many serious accidents, and ability to distinguish at least the primary colors ought to be an indispensable condition for those intrusted with the direction of vessels and employed in the traffic on railways.

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