ease should ever remember that they are put on their good behavior for the rest of their lives.

So much space has been devoted to one of the results of "overwork," that too little is left fully to allude to the other exciting causes of feeble eyesight. We have not deemed it necessary to warn our readers against the fatal results of extraordinary ambition, such as rendered blind the great Milton. His case was one of amaurosis; still this disease seldom follows persistence in literary labor, because few continue their labors as he did after such obvious warnings to stop.

IV. The improper adjustment of light lays the foundation, in many cases, of serious weakness of the eyes. On this subject educated men have much to learn; for while they think that they are acting wisely, they are often imperceptably doing themselves great mischief.

ADJUSTMENT OF LIGHT.

Very few give any attention to this subject until warned by evidences of the failure of eyesight. This warning is ofien practically too late. Light may be deficient, or may be excessive in quantity. The introduction of gas into our private houses has undoubtedly produced injury to the vision on account of its extreme brilliancy, but oftener far on account of its misapplication and mismanagement. The argand burner furnishes light of as good a quality, and a flame as steady, as can be procured in any way. If properly shaded and guarded, no better light need be desired. Several of our eminent jurists, who have much experience in night work, prefer sperm or wax candles. There is no doubt that great improvements will yet be introduced, so that the gas flame will be made to furnish a light more like the white light of day, and more steady. It must of necessity be concentrated, and for this reason be less excellent than daylight; besides, it lacks the chromatic constituents of the light which the sun supplies.

The student by all means should avoid reflected light, or light deficient in chromatic constituents, and alternations as of bright light and comparative darkness. A case is related by a German writer which serves as a good illustration: "A lawyer took lodgings in Pall Mall. The front windows of the house faced the street, and were exposed to the full blaze of the merid

ian sun; while the back room, having no opening but into a small, close yard, surrounded by high walls, was very dark. In this room he performed all his labors and studies, but came into the other to his breakfast and dinner. His sight soon became weak, and at last he was troubled with a continual pain in the eyeballs. He tried glasses of various kinds, and sought council of various oculists, but without obtaining relief. At last it occurred to him that the frequent alternations of light, in going and coming suddenly from the dark study into the bright blaze of the dining-room, might be the cause of his disorder. He immediately hired other lodgings in a different quarter of the city, more favorably situated in regard to the light, and discontinued reading and writing for a while in the evening. This was suf ficient, and soon effected a cure."

The strong, healthy eye bears violent alternations of light and darkness. Not so the eye of one enervated by the want of exercise, undue mental effort, or accidental causes. The blinding influence of the sudden accession of light is illustrated in the well remembered history of Caspar Hauser, as well as in the account of the cruelties of Regulus and Dionysius. It will be remembered that these prisoners, after being confined in dark dungeons, were made blind by sudden exposure to light.

THE BED-ROOM.

The window of the bed-room should not look toward the rising sun. Unless designing to rise before the sun is up, the bedroom window looking toward the east should be carefully protected by a shutter or blind. We have a case of serious ophthalmia now under our care, which owed its origin to a short exposure to sunlight before rising in the morning. Such cases are not unfrequent. For the same reason, namely, that the pupil is in a dilated condition, and therefore unprepared for the accession of light, evil results have occurred from gazing at the moon or at an eclipse, viewing panoramas, and other similar

exposures.

THE STUDY.

The study should be a well-lighted room. The table should be so situated that the light is received high over the left shoulder, in such manner as to bathe the eye and face with

equal light. The light should in no wise be reflected from the paper, or from surrounding objects. Enough light should be received to obtain distinct, easy vision. Too much light dazzles, too little debilitates.

Evening study should not be preceded by "resting" the eyes in darkness. By this means the eyes are not rested, but are rendered less fitted for subsequent labor. It is poor economy to save candle-light. Eyesight is worth more than candles. One of the reasons why artificial light injures the eyesight is, that it is not universally diffused like daylight; it also differs in chromatic constituents, and is unsteady. Artificial light has an excess of red rays, which are longer than the others and penetrate the eye. The admixture of blue rays tends to produce the white light of the day. For this reason engravers place bottles of blue water near their work. The scholar may, to some extent, accomplish the same purpose, by having a lampshade of blue, and a table cover of the same color. Probably the best light that could be afforded would be from numerous gas jets near the ceiling, covered by blue glass chimneys.* Thus daylight would be best imitated. The eye is most rested by green in the day time, and most relieved by blue at night. The study walls should be painted green, the carpet should be of the same color, and the shades. Sometimes window shades of light blue answer very well.

SHADES AND BLINDS.

An intelligent correspondent in Cambridge, Mass., very properly suggests, that curtains as ordinarily arranged shade the window at the wrong end. They obscure the light where it could be received without reflection, and force the eye to bear that which is reflected from the pavement, or from the balcony floor. Unless a grass plot is fortunately situated, the light is seldom favorably modified. Modern inside blinds, made in small sections, afford perhaps the best kind of window shades for every apartment. The student should in every way guard his eyes. Fashion should not induce him to wear a hat with a narrow brim, even at the risk of being regarded outre. It is certain that the present fashion for ladies' bonnets, which are * At our suggestion Cornelius Baker & Co., of Philadelphia, have prepared some blue chimneys for reading lamps of the proper tint.

pinned on the back of their heads, never originated among the thinking of either sex. In relation to this whole subject popular minds little regard its importance. We saw to-day in a shop window a lamp-shade with a bright polished metallic inner surface. It was recommended as economical in so much as it increased the light of the gas jet. The words "a patent applied for," were stamped upon the article. It would be correctly named if called an eye destroyer."

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When gas is used it should never be unshaded. The shade should be diaphanous; it should never be made of thick paper, tin, or any opaque substance, nor should it ever be lined with a reflecting material.

We have suggested a lamp-shade of "blue barege," or "tissue," which being cut of the proper shape, it can be readily drawn over the ordinary wire frame, which is sold in the shops, to sustain the common paper shade. This contrivance is employed and gives much satisfaction in several of our seminaries of learning.

We furnish below a drawing which will guide the reader if he desires to cut a piece of barege or tissue to fit a frame of the description referred to.

The frames are usually two feet eight inches in circumference at the bottom, and fourteen and a half inches at the top. If the shape below is adhered to, a depth of seven inches will leave sufficient room to fold over the

gauze or barege upon either edge of the frame.

BAD HABITS.

Looking at panoramas, fireworks, lightning, reading by the light of the moon or at twilight, the use of the telescope or the microscope, are all dangerous modes of employing the eyes. On this subject we might say much if space afforded. There are two methods of injuring the eye by the false direction of light, which we must pause to mention: that is, reading by a side light, or while lying in bed. The universality of the first FOURTH SERIES, VOL. XIII.-8

habit has led to the frequent observation among oculists that the left eye is most apt to be diseased. The evil effects of the latter are illustrated in the case of a patient who has applied to us while writing this page. He has asthenopia in the left eye, caused by reading in bed while lying upon his right side. It is true the light should come over the left shoulder, but it should fall from above, and the head should be erect.

BEST TIME TO WORK.

It is better to work by daylight, and to use the evening for the lightest literary employments, such as require the least mental effort. The eye so strongly sympathizes with the working of the brain, the student is earnestly advised to a frequent change of literary occupation. With regard to the best time to work, the earliest evening is probably better than the early morning. On this subject individual experience is the best guide. It should never be forgotten, however, that the eyes do not always cry out when they are overworked.

EFFECT OF A DAZZLING LIGHT.

We do not know of a better place than this to enter our protest against the method of lighting churches. We are often told by our patients that it takes half the week to recover from the effects of the gas lights on Sabbath evening. The subject of deranged vision must enter the church, after having passed through darkness from his own lighted home, to meet a glaring, dazzling light wherever he turns his eyes. If he would look at the preacher he must endure the ordeal of facing Argand burners, or gas jets, shining directly in his eyes. Surely on this subject there is too little consideration.

It is said by Mr. White Cooper, of England, that, after the great exhibition of 1851, several instances came under his notice in which the sensibility of the retina was temporarily blunted by the excitement to which it was exposed in that brilliant scene. There can be little doubt, we think, that the more general introduction of gas into our houses has increased the number of cases of morbid sensibility of the retina, for the same reason that such effects were manifest after the great exhibition in England.