A NATION IN SPECTACLES.

Lyttelton Times, Volume CXVI, Issue 14192, 15 October 1906, Page 4

A NATION IN SPECTACLES.

(By HENRY G. MACLAURIN, in tlw “Daily Mail.”) The Englishman who reads without the aid of spectacles will be an object of curiosity before another century dawns. We shall, indeed, by.that time be largely a nation of spectacle-wearers. The average town-dweller will deem a pair of spectacles to be as necessary an adjunct to his personality as a pair of boots, a hat, dr an umbrella. Not that a rapid deterioration of the national eyesight is to be anticipated. Far from it. Spectacles will bo worn not only by people with defective eyesight, but by those whose visual power is normal. ‘ HOW STATURE MAKES LENSES. First let me draw attention to a ro markable organism situated a fraction of an inch behind the transparent front surface of the eyeball—by name,; the crystalline lens. This lens practically is identical with an ordinary magnifying glass of small compass and high ; power. Only between it and the lens of commerce there is a vital point of difference. For example, were it possible for a' man to have the crystalline lens removed (as in a cataract operation), and replaced by an artificial lens of equivalent power, he would have the following curious experience. Everything outside the radius of a few. feet would be seen distinctly; everything inside this radius would be seen indistinctly. He would recognise objects a yard, a frir- ' long, a mile distant] but a page of I printed matter held ten inches from his eyes would present a confused, : undecipherable blur. , This admits of a simple .explanation. An artificial ‘ lens is hen-adjustable, whereas a lens used for near work requires to be of higher focus than, .one , { used for distance. In the .human eye ; nature provides for this contingency in a remarkable and altogether unique way. The crystalline lens,is invested, at its circumference, with a; powerful muscle—the ciliary, .This muscle contracts upon the lexis, thereby reducing its area and causing -it, to bulge; the lens by this means assumes a greater, convexity; becomes, in fact, of higher power, therefore adapts the eye Tor near vision.' , ■ ■ ■ ■ ' 4 OVERWORKED EYES. The action ,of the ciliary muscle ,is automatic. When a person .looks into the distance, the muscle is in a state of , relaxation, allowing the lens to. assume its minimum convexity. On the contrary, fixation of the eyes on a pear object is the signal fox* the ciliary immediately to contract, thus causing the lens to assuino its maximum convexity. Our admimtion for this-wonderful, provision of nature is • not unxningled with apprehension. The demands of present-day commercial life are causing the willing ciliary to he worked to excess. Use, in a word, is giving place to abuse. CHIEF CAUSE OF BAD EYESIGHT. An interesting comparison here Suggests itself'between outdoor workers on. the one hand and/ indoor workers on the other—i.e., between those whose eyes are rarely used for close work anil these to whom close application is habitual. In the former case the ciliary muscles are well-nigh permanently at rest—strain, consequently, is, an unknown quantity. In the latter case the ciliaries are always in active operation, suffering (according to the precis© nature of a person’s employment) maximum contraction for eight, ten, or even twelve hours daily. Frequently these exacting conditions 'have |o be .fulfilled’ by persons totally unfitted by temperament and constitution to discharge them. No matter. Necessity admits of no alternative, save one from , which the brainworker and bread-winner shrinks.' ■'vl . _ But is there no way of relieving the ciliary (muscle of its arduous - arid exhausting task P If so, obviously the brain worker has a valuable asset placed; at his disposal. ■■ I would- say yes—on this ground. That a convex lens of specific power, by being placed before the eye during the time the latter is used for close vision, adds to the strength of tlx© crystalline lens, and thus allows of a proportionate reduction in the contraction of ’the ciliary muscle. Even a perfect ©ye may gain by the aid of lenses (the writer, indeed, can vouch for this from practn cal experience); though, .of course, where the eye is defective/the result- ; ant benefit is immeasurably greater. DISTRESS SIGNALS. A brain-worker using his- ciliary muscles many hours daily and neglecting available precautions must bn© day suffer from eyestrain. _ Eye-etrain, itt, , effect, is synonymous with ovex-worked eye-muscles. There is a certain point, at which the ciliary begins to lagri Be- - yond this point the effoi't to sustain ita contraction is a war against Nature. , The worker is immediately conscious of Nature’s distress signals; is conscious of tlxem but may not heed them. Too often, there is, for him, no respite. Stop be would, if he could; but stoppage would entail precisely those:consequences which most men seek bo avoid. Loss of situation, for instance. Situations, nowadays, ax© an elusive quantity; once lost, they are not easily, regained. To-day,' it is an easy matter for a man who drops out of the running bo go to the wail; easier than : seme people, with superlative _ wisdom and assured circumstances, think. • The worker does not drop out. Ha continues his uphill fight agaxixst ..adverse conditions; overdraws his reserve of nervous energy ; saps his vitality of nerve and bx - ain. Distressing headaches and other' inconveniences are a part'of his daily, life. These frequently are the forewarning of a, complete' breakdown, : The; base is. tact overstated. Doubtless many causes contribute to this _ breakdown,: but eyestrain certainly is not the least; - ■ “ For' many years there- was an - unwillingness, on the part of the medical faculty to give to eye-strain its proper place in their This unwillingness, however, xs rapidly passing away, inasmuch as many doctors now recommend to a qualified oculist; all patients whose symptoms lead them to, suspect the existence of eye-strain. ' .This is as it should be. A-mechanical defect can bo corrected by mechanical means only. To prescribe drugs in cases of headache and other forme of nerve trouble without first liaving ascertained the state of the eyes is equivalent; to nourxng water into a bucket with a bole in it. That the number of spectacle-wearers has largely increased during the last few years is due not to tbe ; fact that , eyesight is more defective than formerly but because, owing to the advance in’ the science of eyesight testing and spectacle fitting, it is possible to give relief through the medium of -glasses in oases where it was deemed impossible. i BATTALIONS OF SPECTACLE WEARERS. Perhaps public education . has had some part in compassing this result, for people how seek the advice of the oculist -where formerly they went with' all speed to the doctor. A marked feature, too, of the present day, is the diminishing prejudice against the wearing of spectacles. Judging by the .re-, cent tests to'which school children have ■ beep subjected, we may safely assume that the next generation \v : 'l scarcely be in advance of this in the matter of good eyesight, and there will be annies of spectacle-wearers where there ar# now merely battalions.