PUNCTURE OF THE BOWEL THROUGH THE ABDOMINAL WALLS. 319 
that the abdominal wound will afterwards be covered by the skin. In 
passing the instrument it is directed perpendicularly to the surface and 
slightly towards the left elbow, and introduced far enough to be sure of 
perforating the bowel. The distance depends on the thickness of the 
abdominal wall. As a rule, the trochar can be introduced for 8^ to 
Fig. 145. — Abdominal organs seen from below. 
C, Caecum; r. v. C, 1st portion of colon ; v. Q, suprasternal flexure ; 1. v. C, 2nd 
portion of colon ; d. Q, diaphragmatic flexure ; D, loops of small intestine , 
M, loops of floating colon. 
4 inches, or even further, without danger. The stilette being removed, 
the abdominal gases discharge through the canula with a whistling 
noise; the canula is left in position until the distension subsides and 
gas fails to reaccumulate. To test this point the canula should be 
stopped with a cork. If tympanites does not recur, and the animal 
shows no further restlessness, the instrument may be removed. The 
procedure is similar to that in puncture of the rumen. lo pi event 
