DISEASES OF THE EYE, OTT 
over it until the entire globe may be hidden from sight. This pro- 
trusion of the cartilage so as to cover the eye may be induced in the 
healthy eye by pressing the finger and thumb on the upper and lower 
lids, so as to cause retraction of the eyeball into the socket. When 
foreign bodies, such as sand, dust, and chaff, or other irritants, have 
fallen on the eyeball or eyelids it is similarly projected to push them 
off, their expulsion being further favored by a profuse flow of tears. 
This is seen, to a lesser extent, in all painful inflammations of the 
eye, and to a very marked degree in lockjaw, when the spasm of the 
muscles of the eyeball draws the latter deeply into the orbit and pro- 
jects forward the masses of fat and the cartilage. The brutal prac- 
tice of cutting off this apparatus whenever it is projected necessitates 
this explanation, which it is hoped may save te many a faithful serv- 
ant a most valuable appendage. That the cartilage and membrane 
may become the seat of disease is undeniable, but so long as its edge 
is thin and even and its surface smooth and regular the mere fact of 
its projection over a portion or the whole of the eyeball is no evi- 
dence of disease in its substance, nor any warrant for its removal. It 
is usually but the evidence of the presence of some pain in another 
part of the eye, which the suffering animal endeavors to assuage by 
the use of this beneficent provision. For the diseases of the cartilage 
itself, see ‘‘ Encephaloid cancer.” 
LACRIMAL APPARATUS. 
This consists, first, of a gland for the secretion of the tears, and, 
second, of a series of canals for the conveyance of the superfluous 
tears into the cavity of the nose. 
The gland is situated above the outer part of the eyeball, and the 
tears which have flowed over the eye and reached the inner angle are 
there directed by a small, conical papilla (lacrimal caruncle) into 
two minute orifices, and thence by two ducts (lacrimal) to a small 
pouch (lacrimal sac) from which a canal leads through the bones 
of the face into the nose. This opens in the lower part of the nose on 
the floor of the passage and a little outside the line of union of the 
skin which lines the false nostril with the mucous membrane of the 
nose. In the ass and mule this opening is situated on the roof instead 
of the floor of the nose, but still close to the external opening. 
EXAMINATION OF THE EYE. 
To avoid unnecessary repetition the following general directions are 
given for the examination of the eye: The eye, and to a certain extent 
the mucous membrane lining the eyelids, may be exposed to view 
by gently parting the eyelids with the thumb and forefinger pressed 
on the middle of the respective lids. The pressure, it is true, causes 
