The effects of ultra-violet rays upon the eye

In 1909 Messrs. J. Herbert Parsons and E. E. Henderson commenced some experiments on the action of short wave-length light on the lens and ciliary body, using Uviol glass mercury-vapour tubes and examining the lens and its capsule after exposure. To test for damage to the ciliary body too slight to be appreciable microscopically use was made of an observation of Römer’s, that in animals sensitised to the blood of another species, htemolysins were not transmitted from the blood to the aqueous unless the constitution of the latter were altered by a previous paracentesis or an inflammatory lesion of the iris and ciliary body. Positive results were obtained, but the experiments were not sufficiently extensive to be conclusive. I have, therefore, on behalf of the Committee of the Royal Society on Glassworkers’ Cataract, repeated and extended the experiments along lines suggested by Mr. Parsons. In the attempt to determine the effect of rays of various wave-lengths on the media of the eye, attention has been paid to three possible aetiological factors:—(1) The intensity of the light. (2) The part of the spectrum mainly represented in the source of light. (3) The possibility of the inclusion of electrolytic and mechanical as well as of radiant energy.