WOUNDS PENETRATING INTO THE CHEST. 5T9 
2. Simple wounds through the parietes of the thorax , with the 
introduction of ciir for a few seconds . 
We effected these wounds with a bistoury, cutting at once 
through the wall of the chest, until we arrived at the pleura, 
which we divided with caution : we held open the edges of the 
wound with a flat piece of iron, and let the air enter during some 
seconds; and we then closed the wound with the same suture as 
in the last case. We have never seen any serious consequences 
from this species of wound. The respiration of some horses 
was not at all disturbed ; others, who were more irritable, heaved 
at the flanks for a few instants; but that was, perhaps, as much 
to be traced to the pain of the operation as to any introduction 
of air into the chest. 
3. Simple ivounds , with the introduction of air into the chest 
during several minutes; and even during some hours . 
The introduction of air into the chest for any considerable 
time has always been followed by symptoms more or less mani¬ 
fest, but these varied according to the manner in which the ex¬ 
periment was made, and the circumstances in which the horse 
was placed. The wound was effected in the middle of the space 
between the third and fourth false ribs. The incision was three 
centimetres long (somewhat more than an inch) externally, and 
from one to two centimetres (one-third to two-thirds of an inch) 
internally, and a current of air was established between the ex¬ 
ternal atmosphere and the cavity of the chest by introducing a 
canula, a centimetre (almost two-fifths of an inch) in diameter 
through the pleura into the chest, and which was plunged in a 
direction from above downwards. 
Soon after the introduction of the canula, the respiratory 
movements became accelerated, and, not long after that, the 
nostrils were dilated. The respiratory murmur could no longer 
be heard, but, on the contrary, and very distinctly, a sound pro¬ 
duced by the friction of the lung against the air introduced into 
the pleural sac, and especially when we closed the aperture of 
the canula. The chest resounded loudly on percussion. These 
symptoms increased in proportion to the length of time that the 
air had access to the interior of the chest. 
As the result of various experiments, we ascertained that, after 
one minute, respiration was simply accelerated; after five mi¬ 
nutes, the nostrils were dilated, and the edges of the nostrils 
curled. Generally the animal coughed hardly and frequently. 
After ten minutes, the flanks began to be considerably agitated, 
with a violent and prolonged contraction of the abdominal muscles ; 
a peculiar sound was heard at the nostrils, which might be called 
nasal breathing (souffle nasal), because it resembled the difficult 
