Color blindness : remarks / by B. Joy Jeffries at the twenty-ninth annual meeting of the board of the supervising inspectors of steam vessels.

Jeffries, B. Joy, 1853-

Date:: [1881]

Credit: Color blindness : remarks / by B. Joy Jeffries at the twenty-ninth annual meeting of the board of the supervising inspectors of steam vessels. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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$dent would certainly have resulted. I would especially recall tlie fact that his right eye, so defective in color sense, had a visual power of six-ninths of the normal, which would have allowed him to have con- tinued in service. And still farther, that the color sense had also fallen in the left eye, where there was still normal visual power. The pa- tient's doubts and my preliminary examination were convincing. Later the left eye also confounded red and green, yet its visual acuteness remained normal or nearly so. Clinical observations have sufficiently demonstrated the not infre- quent occurrence of acquired color-blindness. If, now, its frequency has already attracted attention, it should be still further remembered as being so much more dangerous than when congenital. In acquired color-blindness the person may for many days be quite unaware of his^ altered color-sense, and would only recognize it after repeated mistakes, any one of which under favorable circumstances may prove fatal. Whenever the surgeon suspects acquired color-blindness, the first thing requisite is the examination of the visual field for colors. In these cases we can also question as to color names, since the individual has known them, as we may prove by the color sense of his other eye if perfect, or his having still some color sense remaining. Most cer- tainly the first requisite in the control of color-blindness in certain public services, as of the anomalies of refraction in the army, is to insist on the examiner having a good knowledge of ophthalmology. Injuries about the head, such as sailors and railroad employes are particularly subject to, may cause diminished color perception. Ob- served cases might be cited in support of this statement. Alcohol and tobacco, each alone or when combined, produce, in poi- sonous doses, a deterioriation of the vision and color sense, as has been long known by specialists. This question has been very carefully studied and reported on by ophthalmic surgeons in Europe, England, and this country, quite recently. The results are the same, namely, that alcohol and tobacco together, or each alone, do cause failure of eyesight, both as to form and color. And, what is most important to be remembered, the color-blindness may exist when the person sees otherwise quite well. Hence such a person would escape detection. One of the writers on this topic. Professor iTuel, above quoted, very truly remarks: ^'The ordinary methods of examination would not detect such a color defect, especially at its outset; perimetric examinations are indispensable. These additional and peculiar tests, requisite after sickness and in- juries, are therefore also necessary where there is any suspicion of alco- hol or tobacco, particularly as it is the central portion of the field which is affected, just where we have our best vision. ]Now the point is, that such tests can only be a]3plied by skilled surgeons. The danger from partial or total color-blindness from these causes is the greater since they are sure to be overlooked by non-experts, especially as the visual power for form may be so good as not to call the person's attention to his own trouble, and cause him even to escape detection when exam- ined by the laity. Hence, therefore, the absolute necessity for periodic examinations of those known to use alcohol or tobacco very freely. And similar periodic examinations by skilled experts are equally requi- site for all injured or contused, and those convalescent from exhausting: diseases, before they return to their i30sitions. It will now at once be asked of me, if one out of every twenty-five$