ON LEECHES. 
116 
were fixed in the nasal cavity* ; nevertheless, oil of olives, which 
1 sometimes employed as an injection to get rid of those in the 
nasal cavity (before I observed that they abandoned it of their 
own accord, as they could not live in it so well as in the mouth), 
and it appeared to me to accelerate their fall. Whatever may be 
the success of these means, that which I have always made use of, 
because it seemed to me to be the quickest and surest, and the 
easiest to put into execution on leeches in the mouth, was to 
extract them either with a pair of forceps, or simply with my 
fingers wrapped in lint. 
This operation, which has little difficult in it, nevertheless requires 
a degree of attention and particular precaution, which consists in, 
after having laid hold of the leech by the middle of his body, or, 
what is still better, as near as possible to that extremity which 
adheres to the pituitary membrane, then to extend it gently, yet 
sufficiently hard to fatigue it, but not so rapidly and roughly as 
to tear or break it, which will infallibly happen if we are not 
careful. The strength with which the leeches adhere to the 
membrane by the implantation of their teeth into its tissue is 
usually so great that they would break sooner than let go, 
either from the impossibility of their quickly disengaging their 
teeth, which some say are endowed with a sort of erection and 
cannot be withdrawn for a certain space of time, or from some other 
cause; but the leech which, without being broken, is carefully 
and steadily extended, soon becomes fatigued with this trac- 
tion, and easily comes off of itself. This operation is always 
accompanied by acute pain to the horse, occasioned by some of 
the fibres of the mucous membrane of the mouth being forced out, 
from which sometimes, but very rarely, a slight haemorrhage re- 
sults, but which is never of much consequence. During the 
five years that I was in Spain, and through the summers had oc- 
casion every day to repeat the operation several times, I never 
saw any of those copious haemorrhages which are said to result 
from these cases. The little blood which did flow seemed to me 
too trifling to be worthy the notice of a veterinarian. 
When the leeches are broken in pulling them off, there still 
remains a portion, indefinitely fixed on the membrane of the mouth of 
the horse ; but I have never seen, as some have asserted, that af- 
* And why should we wait for these agents, the action of which is so un- 
certain, when we can produce the same effects with much more facility ? It 
is true that the leeches are sometimes found in the farthest parts of the mouth, 
so that they can scarcely be perceived and cannot be got at ; but they will 
in a short time descend of their own accord to place themselves on parts 
where they may remain for some time, so that it often happens that those 
which could scarcely be seen on the first inspection of the mouth can a short 
time after be seized and pulled out easily. 
