The Bridgeport evening farmer., 1917-09-01
SAVE YOUR EYES
 IS NEW WARNING
Advance in Science of Fit ting Glasses Gan Correct
 Errors in Dogs Eyes

A short time ago, an article was widely published about valuable hunting dog which had been fitted with eyeglasses for astigmatlsIn. Probably most people who read it, laughed and thought that such fake was too palpab1e to be considered in earnest or else that the dogs owner himself was defective in some of the other organs ordinarily carried in the head.
 The modern science of fitting eye glasses, however, mak~s it possible to fit dog, or any other dumb animal, with 8 lens which will correct its eye sight. Up to date methods nave brought about the invention of tnstru. ments by. which the error of the hu- man eye can be accurately measured, and lenses to correct the error pres cribed without asking the patient single question. The silent method" Is very rarely used exclusively, how ever, except in the case of the for eigper, or our friend the dog, when no interchange of thought can be eff fected and the examiner must rely entirely upon the findings of his in Strum entS.
 ] The eye parallels closely the con- ] struction of the familiar camera. It has 8 shutter, a diaphragm, liens,
 a dark chamber, and a sensitized por-
 ton. exactly like the little instrument
 which one may buy at any corner
 drug store. The eyelId serves the same purpose as the shutter, and also | by covering the front of the eye many l times in the course of a day, keeps it
 washed clean from dust, and other
 foreign. substances. The part of the | "a | eyelid is called the cornea. Next in side that is little diaphragm which opens and closes automatically to reg ulate the quantity of light admitted | through the lens. Next is a little | lens made of very elastic, highly | transparent, jelly-like substance call ! ed the lenticular lens. The space be- tween the lens and the sensitized DOT ton of the eye is filled with a vitreous
 substance which is quite transparent. Corresponding with the sensitized plate or film of the camera, the back I portion of the eye is extremely sensi-
 tive to light vibrations and which car l ry the picture as thrown upon them, | to the brain. In some manner which is not yet understood the brain in- terprets the nerve message into a sen- II sation of light.
 | The focus of the 1enticular lens is varied by a series of strong muscles T which have the power either of flat tening it out, which makes the lens
 weaker, or of making it more spheric-
 al in shape, and stronger. This can easily be seen if you shift your gaze
 from this page to some distant object.
 It will be the fraction of a second be-
 fore you will see the sharp outlines of that object suddenly appear. In the
 same manner, looking back at your page, you will find it takes an instant for the print to come strongly into focus.
 This focusing power of the eye is I called the accommo dation, and it is
 when the strength. of the accommo oda- ton muscles is Insufficient to cover all distances or when the retina is . not located at the proper focusing dis
 tance for the lens to receive a sharI
 image, that glasses are made neces-
 sary. When the eyeba11 is so long , that the little image made by the lens comes to as harp focus before ii
 reaches the retina it will be easy tc see objects far away. This condition 7 is called near-sightedness or myopia
 But if the eyeball is so short that the
 retina stops the rays of light before ; they come to a sharp focus, it will bt possible to see objects at a distance but hard to see nearby things. Thi. isc alfed farsi ghtedness or hyeropia
 The work of correcting these de fects is very simple in theory being matter of adding to or subtractins
 from the power of the eye's lens b,
 means of an extra lens of glass tt :, :, make the vision normal. Thus if tht T eye is far-sighted a coSvex lens O ' proper strength will be put in iron ], of it, to shorten the focal distanc, until the sharp image falls on, thu
 retina. In the other case, if the ey, ! is short-sighted, the focal distance 7. will be heightened by the use of
 cOncave lens of glass.
 ? In addition to these two simple CT ! TOTS of eyesight there IS astigmatisfn
 a common error of -refraction. This i
 caused when the curvature of the len : departs from the true spherical shap, 2 and becomes like, the surface of al , eggshell.
 ] In the normal eye the accommoda tive power of the lens to focus itse1 : on different objects is sufficient for great many years but age fina1l , weakens the muscles and hardens tn lens so that it does not readily re ! spond to the impulses received, an, n then glasses are always necessary. Il old age it is generally found that tn . eye can see best at a distance, bu U finds it hard to see things near by Sometimes when the accommoda Etion works perfectly, younger peopI o find it necessary for them to wea
 rest glasses while working Tn : muscles of the eye which bring abou . this accommodation are kept at a Il abnormal strain in order to keep tn
 eyes at the proper focus, but by tn
 use of a lens which will allow ther
 to relax a little. much comfort i
 lsecured. In some cases where yisio
 was apparently perfect, it has bee
 found that this intense strain on tn a accommodation when engaged in nea work not only uses up the entire VI
 tality of the eye nerves but reache - out and saps vitality from the othe d organs of the body, thus giving ris l. to serious functional disorders sue J. as headaches, dyspepsia, insomni tt and quick fatigue.
 le If your eyes burn or smart, if tn l. lids are red. if you cannot keep stead le fly at work for long time, if yo le are nervous or quick tempered-hee le the warning signal and consult an e5 l. perienced ocu1ist, optometrist or opt l. elan. Even if you are already wear r. ing glasses, your eyes may need fui -al has