1 6 Scientific Proceedings (40). 
in a saline bath and more or less under the influence of an anes- 
thetic This method hardly reproduces the normal condition as 
the act of laparotomy reduces and modifies greatly the peristalsis. 
In some instances the movements of the stomach have been studied 
from a gastric or oesophageal fistula and in the rabbit the move- 
ments can be studied graphically, as it has been discovered by 
Auer, in the perfectly normal and unanesthetized animal. 
In the April meeting of last year we presented some tracings 
showing the effect of magnesium upon gastric and duodenal 
peristalsis. At the present time we wish to explain more fully 
the method we have used and to demonstrate the act of obtaining 
the peristaltic tracing. This rabbit was operated four days ago. 
The movements of the stomach and of the duodenum are trans- 
mitted to the kymograph by means of catheters which carry at 
one end small balloons of thin rubber. The balloon end of one 
catheter is introduced and secured in the pyloric part of the stomach 
and that of the other in the descending part of the duodenum 
through openings made directly in each of these parts. By .means 
of a manometer and a rubber bulb which are interpolated between 
the catheter and a Marey's tambour the little balloons in the gut 
can be distended. When not studying the peristalsis the soft 
catheters are secured by means of a bandage around the animal. 
The peristalsis is usually obtained when the animal is in a normal 
crouching position. Soon after the operation there is very little 
peristalsis to be noticed. In the first few days the peristalsis 
improves from day to day in character, intensity and regularity. 
Three to five days after the operation the peristalsis seems to 
assume a normal character, which, however, we shall not discuss 
in the present communication. We wish to state, however, that 
in our earlier experiments in which the duodenal balloon also was 
introduced through the stomach we lost most of the rabbits 
within 24 or 36 hours after the operation. The administration of 
a small dose of physostigmin soon after the operation improved 
our results greatly. At present we introduce the catheter into 
the duodenum directly through an opening in the wall of the latter. 
Our results are now very satisfactory. 
