Art. LIX.—The Effects of School Life on Sight.
[Read before the Auckland Institute, 31st July, 1882.]
It is nearly four years ago I had occasion to examine the sight of the children attending schools in Auckland. In the report of my examination, which was kindly received by the members of the school-board, I stated the percentage of short-sightedness which existed amongst the school-children, and I also pointed out the dangers of school-life in regard to the sight, and how such dangers might be removed or lessened.
During the last three years, while sojourning in Europe, especially in England and Germany, I have still pursued my favourite branch of study, and I have endeavoured to acquaint myself with the progress made and attention given to arrest the pernicious effects of bad light, bad printing, bad ventilation, and bad seats and desks in our schools at home. I have carefully compared the statistics of short sight, taken twelve years ago, with the statistics taken recently and I have noticed that apparently the evil has at least not advanced in its stride. This is no doubt especially due to the
efforts of some of our scientific men, who have repeatedly drawn the attention of the public and of the officials towards the causes which endanger a whole nation to advance from the stage of short sight to that of weak sight. Hirschberg in Berlin, Cohn in Breslau, Sibreich in London, and others, have lectured and written on the subject; and it is my intention in this short paper to give a hurried synopsis of their opinions and of my own observations in this matter.
The changes in the functions of the visual organ, which are immediately developed under the influence of school-life, are the following:—
Decrease of the range of vision.
Decrease of the acuteness of vision.
Decrease of the endurance of vision.
1. Decrease of the range of vision,—short sight,—(Myopia) is that condition of the eye in which rays of light are united in front of the retina in consequence of an extension of the axis of the eye.
As a rule, shortsightedness appears only feebly developed in children, and with proper attention could be stayed, often removed. The most dangerous time for such eyes are the years between eight and fifteen. The visual organ is then in a state of change and growth, and very susceptible to outer influences, the effects of which become easily settled and permanent. When the children look persistently at near and small objects, an undue pressure on the eye is produced by the accommodation muscle, as well as by the accumulation of blood, caused by the stooping position, thus gradually expanding the visual axis. The young scholar not only remains shortsighted, but the defects increase in proportion to the admittance of injurious influences. The sedentary occupations of learned men, or watchmakers, engravers, and others furnish us with a striking example how easily the power of sight for distant objects may be impaired. Shortsighted eyes should not only be guarded against over-straining, especially against evening work, but proper counter-influences against the prime causes should be instituted. In the same degree as excessive working on near objects may gradually produce an expansion of the eyeball from the front to the back, in the same degree could this be prevented by practising the sight upon distant objects, by much outdoor exercise (also school-gymnastics) and carefully guarding against that which is obnoxious to a normal development of the organ. And in sinning against this normally natural development, the schools in particular may be accused. Excessive reading predominates over oral teaching in too great a measure. I do not mean so much in the rural schools or lower public schools, but in the universities and colleges, where a vast amount of mental work must be accomplished in order to enter with honorary degrees into professional life. If extensive
learning is identical with advanced culture, then, indeed, knowledge is a dangerous present of civilization as regards the sight. And if knowledge is transmitted to our brains by means of our eyesight in badly-lighted and badly-ventilated rooms through small and indistinct print, and by sacrificing proper rest and sleep, then shortsightedness will make its appearance in a more aggravated form, and more quickly, than under proper hygienic conditions.
In order to stem the tide of short sight, Prof. Cohn, in Breslau, makes the following demands to the schools throughout the civilized world—demands to which I fully consent:—
For the protection of eye and sight of school-children it is necessary—
To have a pause of fifteen minutes after every lesson of three-quarters of an hour.
To pause half an hour at eleven o'clock, if the morning instructions are carried on during five hours.
To have a reading board for testing the sight fixed in the room. If certain letters cannot be distinguished at a certain distance, the pupil must rest the organ.
To shorten the lessons and the tasks at home.
To introduce lessons on hygiene in all schools, colleges, and universities.
Every Council of Education should have a medical man as a member.
To close, by law, all school-rooms which are badly lighted and insufficiently ventilated.
In Germany, the nursery of short-sightedness, the above injunctions are of vital importance. But also England should adopt them, as the evil of short sight has increased rapidly in that country during the last twenty years. Australia and New Zealand are in a too sympathizing contact with the motherland to be entirely excluded from the unpleasant influences of the latter.
It is true that short-sightedness is often hereditary, but this must not be thought to mean that the children of short-sighted parents are born short-sighted. They have only the predisposition to become so, and their predisposition is developed during school-life, more or less, according to certain external conditions; and the more so, of course, under conditions which tend to produce short sight even in children who have no hereditary predisposition.
Prof. Sibreich points out and demonstrates that short-sightedness has also an injurious influence on the general health by inducing a habit of stooping. Its increase from a national point of view is to be considered a serious evil. In former times, when literary education was confined to a
small number, this question was of little or no importance, but now, especially when England and its colonies are about to extend the benefit of school-education to all children, the question how to prevent short sight deserves serious consideration.
I mentioned in the beginning, that not only Myopia, but also a decrease of acuteness of vision, so-called Amblyopia, is frequently developed during school-life. Often this serious condition is the result of a positive disease in the interior of the eye, which is of too individual a character to be considered here. However, amblyopia of one eye, is mostly produced by unsuitable arrangements for work, which disturbs the common action of the two eyes, and weakens the eye which is excluded from use.
But even more frequently than this defect is a decrease of endurance of the vision—Asthenopia. This very frequent affection, which has destroyed many a career, prevented the development of many a fine intellect, and deprived many of the fruits of their laborious exertions and persevering industry, arises principally from two causes. The first is a congenital condition, called hypermetropia, which can be corrected by convex glasses, and which cannot therefore be laid at the door of school-life. The second is a disturbance of the harmonious action of the muscles of the eye—a defect which is generally caused by unsuitable arrangements for work.
It is not my intention to enter here on a scientific explanation of the various causes of these disturbances of the organ of sight, for the three anomalies I have mentioned all arise from the same circumstances—viz., insufficient or ill-arranged light, or from a wrong position during work.
Insufficient or ill-arranged light obliges us to lessen the distance between the eye and the book while reading or writing. When the eye looks at a very near object, the accommodating apparatus and the muscles which turn the eyes, so that the axes converge towards the same object, are brought into a condition of greater tension, and this is to be considered as the principal cause of shortsightedness and its increase.
How can these evils be prevented? In answering this important question, I do not pretend to express an original opinion only. As a disciple of those great men who have made ophthalmology a flowery limb on the great tree of medical science, I must confine myself to repeat their teaching, and I do so in the firm belief of teaching the truth. But common sense even could answer the question before us.
The light must be sufficiently strong and fall on the table from the lefthand side, and, as far as possible from above. The children ought to sit straight, and not have the book nearer to the eye than ten inches at the least. Light coming from the right-hand is not so good as from the left,
because the shadow of the hand falls on that part of the paper at which we are looking. Light from behind is still worse, because the head and upper part of the body throw a shadow on the book; but the light that comes from the front and falls on the face is by far the worst of all, for, in the first place, it does not attain the object desired, and, next, it is most hurtful to the eyes. It is hurtful because, firstly, the retina becomes fatigued by the full glare upon it, and the diffused light renders the comparatively dark images of the printing and writing more difficult to be perceived. Secondly, the position assumed by the children, in order to avoid the disturbing influences of the light, places the axis of the eye in a very unfavourable direction, which, as I have already mentioned, induces short sight, differences in the sight of the two eyes, and certain weakness of the muscle of the eye.
If, in consequence of such bad light, the child is necessitated to hold the book high up to the face to distinguish the letters clearly, then the consequence will be as before mentioned. The human eyes are moved in different directions by six muscles. The muscles of both eyes can only be brought into contemporaneous action in a certain way. Thus we can only move both eyes at the same time up or down, or bring them together from parallelism to convergence, and vice versa. Of the possible combination of the muscles, some can be brought into action for a length of time, others only for a few seconds. Thus we can only with an effort look at a near object if it is higher than the eye. On the contrary, we can look with ease at an object equally distant if it is below the eye. Therefore you must not think that the natural position of the book while reading depends upon chance. It is a physiological necessity; if we strive against it the eye becomes fatigued, and, if the effort is repeated regularly and for a long time, a derangement of the harmonious action of the muscles of the eye is the consequence.
I have dwelt on these matters exhaustively in a lecture on the human eye which I delivered four years ago in Auckland. I also laid a special stress not only on the pernicious effects of bad light, but also of bad print. Books badly printed or with very small type are certainly not fit for continued use, for in many cases an eye-disease is imprinted therein. In order to prove to you what importance is attached to clearly-printed books at Home, let me state that some years ago the Ministerial Board of Education in Germany condemned over half a million of books by reason of their indistinct type.
With regard to the various positions of the desks and seats, let me quote again Professor Sibreich, who says it is difficult to give an account of the reason for the positions those desks and seats occupy; in fact, they appear
to be the result of mere accident. Sometimes unimportant circumstances—such as the position of the door or fireplace, or the best place for the blackboard—have decided the matter. More frequently it has depended on the desire to have the faces of the children in full light. Against this I have already declared myself. Most frequently, however, the wish to place the children as near as possible to the master has regulated the arrangement, and has led to placing the seats in a horseshoe form; but also in this arrangement only one-third of the children can have a proper light. I admit it is very difficult to answer all requirements in this respect, especially if the schools have not been built with a proper consideration to the hygienics of the human vision. However, in most class-rooms it would be easy to make the necessary alteration—to have the light come from the left-hand side, and, by raising the benches one above the other, or, simpler still, by sufficiently raising the master's place, to enable the teacher to survey the whole class at a glance.
I am afraid my advice in this matter will not soon be practically followed, as even in Europe only after years of urging and preaching have the necessary alterations been made in schools; but my paper has at least drawn attention to the matter, and it must rest in the future what fruit it will bear.