The Manufacturer and Builder 10, 1893
Is color-blindness a product of civilization? An investigation described in Science by Messrs. Blake and Franklin, Physical Laboratory, Kansas University, favors an affirmative answer to the question. Of 159,732 persons tested in Europe and America, nearly 4 per cent. were found to be color-blind. But when the ordinary Berlin worsteds were used to test the color perception of number of Indians, representing many tribes, only 3 in 418, or 0.7 per cent., were found to be deficient. These were full-blooded Indians, and all males. It appears, therefore, that as with civilized peoples, the percentage of color-blind males is greater than that of females.
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