Treatise on the diseases of the eye, including the anatomy of the organ / by Carl Stellwag von Carion ; translated from the fourth German edition and edited by D.B. St John Roosa, Charles S. Bull, and Charles E. Hackney.

Date:: 1873

Credit: Treatise on the diseases of the eye, including the anatomy of the organ / by Carl Stellwag von Carion ; translated from the fourth German edition and edited by D.B. St John Roosa, Charles S. Bull, and Charles E. Hackney. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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$DUST SPECTACLES. [This rule must not be construed into a jjrohibition of out-door life as a means of keeping active the nutritive forces, especially in obstinate forms of sub-acute con- junctival and corneal disease.] a. Dust-Spectacles, Goggles.—Wire-work, in spectacle frames, was at one time used as such, and called by this name. These dust-spectacles have the disadvantage of keeping the eye behind them continually en- veloped in tue vapor of its own moisture, which cannot fully escape. Thus the irritated condi- tion is rather increased than diminished. The principal reason for their disuse lies, however, in the impairment of distinct vision, which compels tne patient to strain his eyes severely in order to see surrounding objects distinctly. By the wire-work considerable objective light is kept away from the eye, and the frame of the dust-spectacles places the translucent gauze in an unfavorable angle to the outer world, tnus Lmiting tne visual held. Moreover, the manifold diffraction which the transmitted light under- goes on tne wire gauze comes into consideration. Besides, when these spectacles are worn in an atmosphere loaded with dust, the meshes of the gauze become tilled, and then their defects are increased. Ordinary glass spectacles, of circular shape, about an inch in diameter, are to be preferred to the dust-spectacles above described. Of course they protect the eye less; but where the clust is so abundant that sufficient protection is not afforded by the ordinary glass spectacles, or where a small amount of dust upon the eye proves injurious, the surgeon does well to prohibit the patient from being thus exposed. 3. A very common source of injury, among certain kinds of laborers, is the chip- ping off of bits of metal, stone, and the like (Stavenhagen), which come with great force upon the eye, and sometimes even enter it. These must often be removed by the aid of instruments, which usually cause considerable irritation and loss of substance. According to the detailed statistics of H. Cohn, almost half of the workers in metal suffer from such injuries. Wearing ordinary glass spectacles would diminish the danger somewhat, but they are too easily broken and too expensive to be com- monly used. Mica spectacles have therefore been introduced, but as yet they are unfortunately not generally employed. They are thin, almost perfectly transparent disks of mica in metallic frames, fitting well on the orbital ridge, and which are fastened on the head by a bandage, or, better still, by means of an ordinary specta- cle-frame_(i£ Cohn). They do not break, and are cheap. Besides, mica is a poor conductor of heat, and in working over tire it does excellent service, especially if colored blue or gray, in neutralizing the bright reflection. B. Among chemical causes of injury, our attention is especially called to 1. Uncleanliness of the edges of the lids or of the conjunctival sac. Among children we cannot give the matter too much attention, particularly where the case does not permit the use of the protective bandage. Children in play- ing are apt to soil their face and hands every moment, and rub the dirt into their eyes in order to alleviate itching. The rules for avoiding this are evident. It is only necessary to remark in passing, that those who have the care of children with eye-disease should be impressed with the necessity of keeping them away from all diity places or dirty substances. 2. The action of remedial agents.—Eye-washes, ointments, etc., which are employed at an improper time, or in too strong a solution, or too often, immediately upon the conjunctival sac or the globe, may be harmful by increasing the irritation or inflammation. Besides this we may mention salves, tinctures, and the like, which are used only for their irritative, absorbent, or narcotic effect, and which are applied to the lids or their vicinity; meal poultices, vegetable decoctions, baths which have been made more active by the addition of salts, etc. Among$