Color-names, color-blindness, and the education of the color-sense in our schools / by B. Joy Jeffries.

  • Jeffries, B. Joy (Benjamin Joy), 1833-1915.
Date:
1882
Catalogue details

Licence: Public Domain Mark

Credit: Color-names, color-blindness, and the education of the color-sense in our schools / by B. Joy Jeffries. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    5/16 (page 3)
    rare that the term color-blindness means, now-a-days, red or green blindness. It will be noticed how these colors correspond to the sen- sation derived through the three retinal zones before described, etc. Whilst the mistakes as to colors a color-blind makes are very charac- teristic, and seem most extraordinary, yet when we come to define what the defect is, it will be found not so easy or simple. Perhaps the best conception, and one most readily retained and kept in mind, is this ; viz., that to the color-blind (red or green-blind) all colors con- taining either of their two defective ones become so much darker, and seem as if they had been made with gray, or black and white mixed. This, of course, is in proportion to the amount of the color-blindness and the amount of the red or green in the given color. Color-blindness has not been detected by present methods of teach- ing colors by charts, colored objects, etc. It has escaped detection even where the best methods were employed by very intelligent teachers. This, however, is not so strange when we realize how it is not discovered in every-day life, and that even the adult and edu- cated color-blind are found ignorant of their defect, often stoutly re- senting any lack of chromatic visual power.' Recent extended research has proved some facts in relation to color-blindness which must be taken into consideration in relation to teaching colors in the schools. It is a congenital defect, and, as has been said, much more frequent in the male than in the female. It is hereditary, and follows the general law of heredity. Females, though they escape it, transmit it to their male offspring. As there is no rule without an exception, so here also the defect has been found in all the females of several generations of one family, and only in them, the males, normal-eyed. It may occur congenitally in one eye only. Several monocular cases have been seen and carefully ex- amined by very competent observers. Age, color, race, civilization, or occupation do not seem to have any influence on its frequency to judge by present statistics. The color-blind who can be put into the so-called hypnotic or mes- meric condition have temporarily been able to see colors normally ; also the normal-eyed who can be put into this condition arc rendered, for the time they are so, like the color-blind as to chromatic sense. Injuries which affect the brain may cause what is practically color- blindness, and in one eye only. Such cases are recorded. It has long been known as a symptom of certain cerebral affections, or cerebral and ocular troubles described in ophthalmic treatises. A condition of chromatic defect simulating perfectly color-blind- ness is produced by chronic poisoning from alcohol and from tobacco,