10 MR. youatt’s veterinary lectures. 
enlargement of, or the most capacious part of the lachrymal duct, 
and to a person possessed of common eyesight it is plainly enough 
a sac. 
A long canal here commences, and runs down the lachrymal 
and along the maxillary bone, very small, and with difficulty 
admitting any probe. Passing over the maxillary, it takes a di¬ 
rection a little superiorly, so that it must not only be a small, but 
a flexible probe, to pass through it. About an inch and a half 
down the maxillary, and not more than half an inch from the 
foramen infra orbitarium posteriorly, and a little superiorly, it 
enlarges, and becomes membranous, and is continued downward 
until it terminates on the inner and inferior part of the nostril, 
below the proper lining of the nostril, and on the cuticle. It ter¬ 
minates on the cuticle, that the highly sensitive membrane of 
the nose may not be excoriated by the tears, occasionally ren¬ 
dered acrimonious, in inflammation of the eye. The oval ter¬ 
mination of this duct is easily brought into view by lifting the 
nostril. 
We shall have, by and by, to speak of a disease, which is 
characterized, in its later stages at least, by ulceration of the 
Schneiderian membrane, and ulcers of a chancrous nature assum¬ 
ing a definite rounded or oval form. Take care that you do not 
mistake this for one of them, or pronounce a healthy horse to be 
glandered, because, for the first time, you happen to observe the 
termination of this duct. It is a mistake that has been made by 
many a good horseman, and even by some veterinary surgeons. 
A little while ago I was sent for in great haste by the coachman 
of one of our four-in-hand gentlemen. I found him in sad tribu¬ 
lation ; one of his master’s best horses was glandered, and the 
disease would run through the whole team. It was the first time 
that this aperture had attracted the attention of a man who would 
not have yielded to any one in pretension to horse-knowledge. I 
knew one of your brethren who would otherwise have passed a 
veiy good examination, but he happened, unfortunately, to say 
that the nasal duct opened on the Schneiderian membrane; and 
he was turned back on this point of practice. 
FISTULA LACHRYMALIS. 
From some occasional acrimony of the tears, the membrane lin¬ 
ing this duct may inflame and thicken ; or some foreign body may 
insinuate itself into the duct; or some unctuous matter from the 
ciliary glands; and the fluid accumulates in the sac and distends 
it, and it bursts: and the ulcer eats through the integument, 
and there is a small fistulous opening beneath the inner canthus 
