EYE-SIGHT, ITS DEFECTS AND TREATMENT. 



273 



emphasis in his recent work on " Eye-sight, 

 Good and Bad," on the inexpediency of post- 

 poning the use of artificial aids when they are 

 needed. The failing of sight for near objects 

 is the result of a loss of adjustability in the 

 crystalline lens which can never be regained, 

 and the loss will be accelerated by overstrain- 

 ing the eye. Spectacles should be resorted to 

 as soon as they are needed, and should be 

 always carefully adjusted to the actual need. 

 Mr. Carter says : " It can not be too generally 

 understood that spectacles, instead of being a 

 nuisance or an incumbrance, or an evidence of 

 bad sight, are to the far-sighted a luxury be- 

 yond description, clearing outlines which were 

 beginning to be shadowy, brightening colors 

 which were beginning to fade, intensifying the 

 light reflected from objects by permitting them 

 to be brought closer to the eyes, and instantly 

 restoring near vision to a point from which, 

 for ten or a dozen years previously, it had been 

 slowly and imperceptibly, but steadily, de- 

 clining. This return to juvenility of sight is 

 one of the most agreeable experiences of mid- 

 dle age ; and the proper principle, therefore, is 

 to recognize loss of near sight early, and to 

 give optical help liberally, usually commencing 

 with lenses of + T25 or + 1'50, so as to render 

 the muscles of accommodation not only able to 

 perform their tasks, but able to perform them 

 easily. When, as will happen after a while in 

 consequence of the steady decline of accommo- 

 dation, yet more power is required, the glasses 

 may be strengthened by from half a dioptric to 

 a dioptric at a time, and the stronger glasses 

 should at first be taken into use by artificial 

 light; the original pair, as long as they are 

 found sufficient for this purpose, being still 

 worn in the day-time." Mr. Carter and Dr. 

 Harlan both strongly recommend, whether for 

 the failure of near vision or for near-sighted- 

 ness, the use of spectacles in preference to eye- 

 glasses, which are less perfectly adjusted before 

 the eyes and less steadily held in place. 



Short sight is a defect of vision which arises 

 from no natural or progressive modification of 

 the organism of the eye, but it is often aggra- 

 vated and indeed produced by the bad condi- 

 tions under which the eyes are used. The or- 

 ganic cause of myopia is a too great depth of 

 the eyeball, which causes the sharp image of 

 an object to be formed in front of the retina 

 instead of directly upon it. Eyes that are sub- 

 ject to this defect have a very sharp vision for 

 objects held quite close to them, but at a little 

 distance the outlines become blurred and the 

 details indistinct. The remedy is spectacles 

 with concave glasses, which should be adopted 

 promptly when the need is discovered, because 

 by constant straining of the eye its defect will 

 become aggravated, even if an actually diseased 

 condition is not induced. The organic pecul- 

 iarity which is the cause of near-sightedness is 

 often inherited, and some children are myopic 

 at birth, but in general it is only the tendency 

 that is congenital. This may be held in check, 

 VOL. xxi. 18 A 



or it may be accelerated, and very often near- 

 sightedness originates in later life. It is most 

 prevalent where civilization is farthest ad- 

 vanced, is more common in old than in new 

 communities, in cities than in the country, 

 among brain-workers and cultivated people 

 than among laborers and the illiterate. There 

 is a general agreement among authorities that 

 a great development or increase of it takes 

 place during school-life, and the result is largely 

 due to preventable causes. "There is no longer 

 any room for doubt," says Mr. Brudenell Car- 

 ter, "that badly-lighted and badly-fitted schools 

 form a great machinery for the development 

 of myopia, and it is probable that this ma- 

 chinery, where, as in Germany, it has for a 

 long time been in unchecked operation, may 

 have an important influence upon the form of 

 the eyeball, which will be inherited by large 

 numbers of the population." Dr. Harlan de- 

 clares that " it has been positively established 

 by careful and extensive statistics that short 

 sight is more frequently, if not almost exclu- 

 sively, developed during school - life." Dr. 

 Colin, of Breslau, reported, as the result of 

 an examination of 10,000 school-children, that 

 1,000 of them were near-sighted, and he found 

 that the defect increased numerically as the 

 pupil advanced through the different grades 

 of the schools. He found 6'7 per cent of my- 

 opia in the elementary, 10'3 in the interme- 

 diate, 19 - 7 in the high schools, and 26'2 in 

 the gymnasia. Similar investigations with like 

 results have been made by Dr. Erismann, in 

 Russia, and by Drs. Agnew, Loring, and Lundy, 

 in the United States. Dr. Lundy, of Detroit, 

 found an increase of near-sightedness in a 

 twelve years' course at school from at the 

 beginning to 12 per cent in the highest grade, 

 a progressive development of 1 per cent a year. 

 Imperfect light, impure air, bad construction 

 and arrangement of desks and seats, and badly- 

 printed books, are among the causes assigned. 

 Dr. Donders, of Utrecht, declares that " the 

 foundation of near-sightedness is mainly laid 

 in schools, where, by imperfect light, the pu- 

 pils read bad print or write with pale ink." 

 Another cause of injury to the eyes, as well as 

 the general health, is the admission to schools, 

 and too close confinement there, of children at 

 a too early age. 



There is a form of imperfect vision known 

 as astigmatism, which is caused by a more or 

 less irregular curvature of the front part of the 

 eye. "When it exists to any marked degree, 

 vertical and horizontal lines can not be dis- 

 tinguished with equal clearness. It is in some 

 measure corrected by the use of glasses with a 

 cylindrical instead of a spherical curvature. A 

 structural defect of the eye, in the treatment 

 of which great progress has been made, is that 

 known as cataract, in which the crystalline 

 lens condenses and thickens until it becomes 

 impermeable by light. It is now very effectu- 

 ally treated by the complete removal of the 

 lens, the place of which is supplied by a 



