BIT OF PERCUSSION-CAP IN THE EYE.

A bit of exploded percussion-cap entering the eye is usually fatal to the injured organ. Children are fond of exploding caps with a hammer or stone. It is an extremely dangerous pastime; and an eye being struck, an oculist should be at once consulted, as there is danger, not only of the loss of the eye, but, if certain unfavourable symptons are neglected, of the loss of the other uninjured eye as well.

SYMPATHETIC DISEASE OF THE UNINJURED EYE.

This may occur if a wound in the fellow-eye is very serious, or if a bit of metal has lodged within it. It is imperative therefore in these cases to seek competent advice, not wholly for the sake of the injured eye, but to save the sound eye also. To save the uninjured eye, it is sometimes advisable to have the injured eye removed, so as to prevent the spread of the inflammation to the sound one and avert blindness.

ARTIFICIAL EYES.

An artificial or glass eye is a thin shell of glass or porcelain, made to fit over the stump or remains of an eye that has been removed, or has been lost by disease. It is painted in imitation of the natural eye, and in favourable cases is easily mistaken for it

across the room. It is usually inserted in the morning by the wearer, and removed at night; and when charlatans advertise that they insert artificial eyes without pain, they only promise to do what every wearer of a glass eye does for himself every day.

THE EYES OF CHILDREN.

New-born babies are subject to a dangerous inflammation of the eyes, coming on two or three days after birth. There is great swelling of the eyelids, and later a copious discharge of matter from the eyes. This discharge is contagious, and coming in contact with healthy eyes, may give rise in them to a similar disease. Great care should be taken therefore to keep the child apart from others, and the greatest cleanliness should be provided for. The affected eye or eyes should be syringed out every hour with warm water, so that the poisonous matter may be removed as soon as formed. When severe, this affection is very dangerous to the sight, and therefore the best medical aid-an oculist, if possible-should be summoned without delay.

CATARACT IN CHILDREN.

When children are observed to avoid a bright light in reading and study, and are noticed to hold the book more or less at one side, as well as very

near the eyes, it probably will be found that they have cataracts. A cataract is an opacity of the lens, L in Fig. A below. This lens in health is quite transparent like glass, but in cataract it becomes opaque and unclear, somewhat like ground glass. The centre of the lens, right behind the

middle of the pupil (P), is generally the most opaque. The pupil (which is the hole in the iris) has, as is generally known, the power of enlarging in a dim light, and of growing smaller in a bright light. The larger this hole or pupil, the better the child with cataract sees; and therefore a dim light is preferred for reading. If the opaquest part of the

lens is not exactly in the centre, but more at one side, then the print will be read more easily by holding the book slightly at the other side of the eye. And always the book must be held quite near, to aid the eye in its difficult task of seeing through an unclear lens.

By looking at the figure, it will be seen also that any spot on the transparent front of the eye (C) that covers the pupil and iris (I)-very much as a watch-glass covers the face of a watch-would also make sight imperfect and difficult. But if the front of the eye and lens are clear and the pupil open, the eye being well formed, a loss of sight must be due to disease in the back of the eye,in the retina (R) and its adjacent tissues, or else the optic nerve (ON) for some reason fails to carry the impression of sight in the eye to the brain.

WHAT TO DO FOR CATARACT IN CHILDREN. In these cases an oculist should be seen in order to determine whether it be cataract, or near-sight, or some other affection. If cataract, then he will advise its removal; or, if small or at one side, perhaps the making of an artificial pupil instead. As an eye covered by a cataract gradually loses its visual power through want of exercise of the sight, advice in these cases should be sought during the early life of the child.

E

OVER-SIGHT A CAUSE OF SQUINT OR CROSS-EYE.

The defect of sight called over-sight, the opposite of near-sight, is sufficiently explained at page 20. It is sometimes the cause of weak sight in children, and is then to be treated as directed on pages 58, 59. It is also the usual cause of a turning inward of one or both eyes, constituting squint or cross-eye. In the beginning of this squint, if the child is old enough to be fitted with proper convex glasses, the affection may be cured by thus curing the oversight. But if the trouble is one of years' standing, it should be cured by a surgical operation. Go to a good oculist, and he will cut the muscle of convergence (M C in the figure, p. 48), and this will restore the eye to its proper position.

PROGRESSIVE NEAR-SIGHT IN CHILDREN.

Near-sight in children is noticed usually at about the age of seven or eight or earlier, if the tendency is inherited; and from this age up to that of fifteen or sixteen, if acquired. It is probably very often acquired, oftener than is generally supposed; at least, it is often observed when neither parents nor relatives, so far as can be learned, are similarly affected. Too much study, too much school, too continuous use of the eyes on near objects, too little out-door life and exercise of the eyes in