SAVING THE EYES

New Zealand Times, Volume L, Issue 11583, 28 July 1923, Page 15

SAVING THE EYES

ADVICE TO SENIOR CADETS SOME USEFUL HINTS. (By Dr. E. L. Marchant.) “The eyes,” says Dr. Marchant, “are deleoate organa given us for use, but unrortunateiy they are often misused. Misuse means using them m auoh u manner os to throw undue strain on either tbe muscles moving tbe eyes, on the muscle' inside the eye which focuses the rays entering the pupil, or on the retina which receives the impressions and passes them on to the brain. HOW UNDUE STRAIN MAY ARISE. “Undue strain may come about by-. “1. treading or writing in a bad light -which requires 'bringing the eyes toe near the o&ject since to do this the eyes must be rotated inwards unduly and held there hy the muscles. No effort is required of tho muscles in looking straight ahead, but when they hare to keep the eyes in any other position for a long time they become tired. Also the focusing muscles has to work unduly to keep up dear right and the retina becomes tired through the effort to work in insufficient light. “2. Reading or writing in a bad position has a similar result since the muscles are required to help the eyes in some abnormal situation, and so are oveiwonked. This is why reading in -bed lying on the side is so tiring, as is lying far back in a chair, since the muscles which draw the eyes downward are in action all the time, and sometimes several groups of muscles are called upon for undue effort when looking down and also sideways. The correct position is sitting straight up with a book or paper inclined towards you ind the lignt falling from behind over the shoulder. In writing it must fall from the left to avoid throwing a shadow of the hand on tho portion of paper in use. “3. Reading small type or doing fine line drawing entails bringing the eyes too 1 near the object so as to en large the images entering the eye. The focusing muscle is left at tension and the muscles drawing the eyes inwards also, since the nearer the object the more musj the eyes he converged. Badly printed matter is de letorious in the same way as'the various parts of the letters have nut clear outlines, and the more indistinct tho print the greater the effort required to read it. Print should have the vertical components of tho letters darker than the horizontal ones for ease in reading. The typewriter has this defect, that the vertical and horizontal (components aro almost equal and also the contrast between coloured letters on white paper is less than between black on white. “Too little or too milch light can be equally tiring, since the former embraces- most of the defects already mentioned, while a glare tires the retina and the muscle governing the pupil which is in.constant action in endeavouring to shut out the excess of | light. Eyoyibody must hav„ noticed the pain caused in going into a [bright light from darkness, and to a

less degree the same thing ooours by using too muoh light in working. SHORT SIGHT CAUSED BY MISUSE. “4. The roost potent cause of eye strain tomes aibout .by using ey es which have defective sight without correcting glasses. There aie. three main detects which can be more or less well corrected by glasses.. These are: Socalled long sight, short sight, and astigmatism. Dong sight renders near work difficult and the focusing muscle is called upon unduly. The same thing happens with astigmatism but both can te satisfactorily corrected and then the eyes work normally. Neither of these defects is acquired by misuse, hut both are due to defective shape of the eyes, through bad development and usually the defect does net become Worse. Short sight is in a large number of oases caused by misuse. It not only tonds to become worse, but may reach such a high de gree as to render the subject practiaally .blind. Overuse and misuse of the eyes during the years of growth are mainly responsible for short sightedness, though undoubtedly there is some weakness in the fabric of the eyeballs in people who become very short-sighted. Dong sighted eyes and those with astigmatism may; subsequently become short-sighted by overuse without glasses. Glasses are given not only to. make a person see more clearly, blit also to endeavour to' prevent a defect becoming worse, and. also to do away with strain. Near sighted people seldom.' have trouble in near work and often do not realise how had their sight is until it is compared with that of one normally sighted. (‘One is so often told Ire parents when speaking of short-sighted children that they cannot keep these children away from books. Not only aie they usually children who overread, hut they tend to read in a bad light. THE EFFECTS OF EYE STRAIN. “Some of the effects of eye strain are: A. Headaches, usually after work, more felt in the forehead or behind the eyes. B. Soreness oi the eyeballs and eyelid* giving a feeling of heat and gnttiuess. C. Sensitiveness to light which may '.become very troublesome. ‘•if use of the eyes be persisted in, the edges of the eyelids became red and sore, and the eyeballs bloodshot, whila the edges of the eyelids stick to gether and matter may be found in the eyes in the morning. More die. taut effects fall on the nervous system, making the person either irritable or sleepy; and it is now generally lecog uiaed that eye strain is the source of ■many nervous troubles. “A well-known American eye specialist says: ‘To conserve the vision of the rising generation every child’s eyes should be examined by an eye specialist on entering Bchooi, and •very year afterwards.’ “This may seem .an extreme view, but so often are defects found which have been -quite unsuspected that much trouble would be prevented were it carried out. If even a numbei Of children were prevented from becoming short-sighted this dictum would be justified. “In addition to good lighting, good print, and corrected glasses, fresh air is most -necessary. These delicate organs cannot be expected to work normally unless supplied with healthy, blood as is easily found by anybody who works in a stuffy room. Inva-

lids should not be allowed to. read all | day, as they sometimes are, since the eyee during illness are weakened and calling an them to work overtime' is 11 only courting disaster, as many have found when it is too late. “SQUINT” AND EYE AGCffDUNTS. “All are familiar with the condition known as ‘squint,’ where one eye looks straight whil© th© othor mwirds or outwards. This defect is' in most cases due to difference between the sight of the two eyes, and if,treated early enough most oases are durable by glasses and treatment- A fact about squint now generally recognised is that if left alone the .squinting..eye does not develop, and is later found to be practically blind. Squint usually develops before four years of age, and if treatment be commenced at once—even sis early as two years the sight of the Bquinting eye can nearly always be .developed. Many people say squint disappears when children get older, and so it sometimes does; but usually only when the squinting eye baa become blind, and no longer attempts to see. “Concerning eye accidents such as the lodging of particles of grit «r fragments of metal, on the eyeball:— These should be removed as soon as possible, since the longer they remain the mode /flamed the eye becomes, and the greatet'is the damage to sight likely to os. The particles themselves are usually only skin deep, and if cleanly removed by a sterilised instru rhent auch as a doctor uses, there will be no danger. ■ It is the presence of microbes in • the little cut which' are dangerous, smee by causing inflammation ted extraction of part ot the eye* Mid this mat be eo extensive that the eye is lest alto, gether Wu this reason trving to remove these fragments with' ar pocket handkerchief is -as drmrr-rons as using a horseshoe nail. If dtfet gets into the eve it will fireneWdlv come, out if the eves he opehed'and sHu't . under water. Do not. mb' the eves, as this only drives the particles in deeper or scratches the front of the eye. The | heat Instrument to use is a child’s paint brush dircr-d in castor oil. If this fails * doctor should he consulted as the chance of losing eyesight is .not. worth risking DEAT/TW WITH-INFLAMMATION. “Inflammation e£ thq eygi is often

treated at home by such reraedicn tie-leaf pouiUces and mil* Anu t better application ie common salt at the rate of a level teaspoonful in a pint of warm water. Inis is an efficient cleanser, and has no bad points. Boracio acid is much used, but with some people it Is irritating, whereas salt never is This condition of inflammation u often brought about by wiping „ the eyes with a handkerchief. This article must always be full of microbes after it has been used, and should never be used as an eye duster In». flammation should not be allowed to remain- untreated, so consult a doctor as soon as possible Dealing with the question of: tseth preservation. Dr. Merchant wpd that children and adults ehorcld eat- at least seme brown bread for meals, also, wall cooked vegetables and a little fresh fruit to finish with, and fafihsu. taut the teeth should be <3 tubed at least twice dally, and preferably-; after autfe