d form of
sore eye, as _congestion of the eyelids_, and the more severe type, as
true _conjunctivitis_ (see p. 18).

=CONGESTION OF THE EYELIDS.=--This may be caused by smoke or dust in
the atmosphere, by other foreign bodies in the eye; frequently by
eye-strain, due to far- or near-sightedness, astigmatism, or muscular
weakness, which may be corrected by an oculist's (never an optician's)
prescription for glasses. Exposure to an excessive glare of light, as
in the case of firemen, or, on the other hand, reading constantly and
often in a poor light, will induce irritation of the lids. The germs
which cause "cold in the head" often find their way into the eyes
through the tear ducts, which connect the inner corner of the eyes
with the nose, and thus may set up similar trouble in the eyes.

=Symptoms.=--The eyes feel weary and "as if there were sand in them."
There may be also smarting, burning, or itching of the lids, and there
is disinclination for any prolonged use of the eyes. The lids, when
examined, are found to be much deeper red than usual, and slightly
swollen, but there is no discharge from the eye, and this fact serves
to distinguish this mild type of inflammation from the more severe
form.

=Treatment.=--The use of dark glasses and a few drops of zinc-sulphate
solution (one grain to the ounce of water) in the eye, three times
daily, will often cure the trouble. If this does not do so within a
few days then an oculist should be consulted, and it will frequently
be found that glasses are needed to secure freedom from irritation of
the eyes. In using "eye-drops" the head should be held back, and
several drops be squeezed from a medicine dropper into the inner
corner of the eye.

=CONJUNCTIVITIS; CATARRHAL INFLAMMATION OF THE EYES.=--In this
disorder there is discharge which sticks the lids together during the
night. The inner surface of the lids is much reddened, the blood
vessels in the lining membrane are much enlarged, and the lids are
slightly swollen. The redness may extend to the eyeball and give it a
bloodshot appearance. There is no interference with sight other than
momentary blurring caused by the discharge, and occasionally there is
very severe pain, as if a cinder had suddenly fallen in the eye. This
symptom may occur at night and awaken the patient, and may be the
reason for his first consulting a physician.

One eye is commonly attacked twenty-four to thirty-six hours before
the other, an