The influence of light on the skin / by Robert L. Bowles.

  • Bowles, Robert L. (Robert Leamon), 1834-1913.
Date:
[1897?]
Catalogue details

Licence: Public Domain Mark

Credit: The influence of light on the skin / by Robert L. Bowles. 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.

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    “ For a healthy condition of the retina and epidermis it is necessary that the ratio between the intensities of the radiations in different parts of the spectrum shall remain nearly constant. “ Neglecting the effects produced by the phenomena of fluorescence and calorescence we are justified in making the following assumption. In the reflected light from snow the heat rays are nearly entirely absent, the violet (chemical) rays would be present with almost the same intensity as in the direct sunlight. It must be remembered that we are not here dealing with reflection from a plane surface. In snow the surface is so rough that an incident beam of light is completely dispersed at its surface, and the illumination of a point above the snow will not vary, within limits, with the angle of the incident beam. “ Considering the lack of evidence in favour of the X-rays pure and simple, being a cause of dermatitis similar to sunburn, it is worth while reviewing the facts in support of the theory that the true cause is to be found in the violet, or chemical rays, or in the increase of intensity of the violet rays with regard to the intensity of the red rays. “I think that the facts cited in your paper (British Medical Journal, March 7th, 1896), particularly in sections 5, 6, 8, 11, 14, &c., furnish sufficient support.” Here you see, from an entirely physical point of view, Mr. Travers, like Widmark and others, arrives at conclusions similar to my own—namely, that the vital changes on the skin are due to the chemical rays, and apparently to the chemical rays alone, and that the rays issuing from a Crooke’s tube are not an entirely new form of energy distinct and separate from light, but contain a proportion of luminous and chemical rays, and that light, as such, as well as the divisions into which it can be split up, may penetrate wood, clothing, and the human tissues. Immediately on the publication of Professor Roentgen’s discovery, I claimed for the X Pays, as then produced, an affiliation to those of light, and pre- dicted (Lancet and British Medical Journal, March, 1896) that they would be found to affect the tissues in a way similar to the violet rays of light. It was not long before this was shown to be the case, and various and intense forms of dermatitis ending even in necrosis have now become, unfortunately, a common experience. Whether