s the use of the conjunctiva? How are the white spots
frequently seen upon the eye accounted for?

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910. There are found several small glands on the internal surface of
the cartilage, which have the appearance of parallel strings of
pearls. They open by minute apertures upon the edges of the lids. The
secretion from these glands prevents the edges of the eyelids from
being united during sleep.

911. The edges of the eyelids are furnished with a triple row of long,
thick hairs, called _eyelashes_, which curve upward from the upper
lid, and downward from the lower, so that they may not interlace with
each other in the closure of the eyelids. These appendages of the eye,
by closing, not only protect it from moisture, but from dust,
particularly during sleep. They likewise, by their movements in
opening and shutting, spread the lubricating fluid equally over the
eye.

912. The LACHRYMAL APPARATUS, which secretes the tears, consists of
the _Lachrymal Gland_ with its ducts, _Lachrymal Canals_, and the
_Nasal Duct_.

913. The LACHRYMAL GLAND is situated at the upper and outer angle of
the orbit. It is about three quarters of an inch in length, flattened
and oval in shape, and occupies a depression in the orbital plate of
the frontal bone. Ten or twelve small ducts pass from this gland, and
open upon the upper eyelid, where they pour upon the conjunctiva the
lachrymal fluid, or tears. This secretion is maintained while we are
asleep, as well as when we are awake. The eye from this cause is kept
constantly moist.

914. The LACHRYMAL CANALS commence at minute openings upon the free
borders of each eyelid, near the internal angle of the eye, by two
small orifices, called _punc'ta lach-ry-ma'li-a_, (tear points.) Each
of these points communicate with the sac at the upper part of the
nasal duct.

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910. What are found on the internal surface of the cartilage of the
eyelids? Where do they open, and what is their use? 911. With what are
the edges of the eyelids furnished? What are their uses? 912. Of what
does the lachrymal apparatus consist? 913. Describe the lachrymal
gland. How many ducts pass from this gland, and what do they convey to
the eye? Why is the eye constantly moist? 914. Where do the lachrymal
canals commence?

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915. The NASAL DUCT is a short canal, about three quarters of an inch
in length, directed downward and backward to t