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on which the action of the heart depends , &c. 
pressure, either on ihe brain or spinal marrow, produced 
little or no effect on the action of the heart. Its action could 
be influenced by stimuli applied to the brain and spinal marrow 
long after the circulation had ceased. 
The peristaltic motion of the intestines, as far as we could 
judge from the following experiments, obeys the same laws 
as the action of the heart. 
Exp. i 7. A rabbit was deprived of sensibility by a blow on 
the occiput. The whole of the spinal marrow was then de- 
stroyed by a hot wire. On opening the abdomen, we found 
the peristaltic motion of the stomach and small and great in- 
testines quite as strong as when the nervous system is entire, 
as we ascertained by exposing the abdominal viscera of other 
rabbits. In another experiment, the spinal marrow was wholly 
removed, without at all affecting this motion. The removal 
of the brain, we found, produces as little effect upon it, as that 
of the spinal marrow. When both were removed at the same 
time, it remained unaffected. It continues till the intestines 
become cold, so that when the portions exposed to the air 
have lost their power, the motion of the parts beneath still 
remains. 
We endeavoured to ascertain how far this motion is influ- 
enced by stimuli applied to the brain and spinal marrow, but 
from its nature it is in every way so irregular, that no certain re- 
sult can be obtained. It often appeared to us, that spirit of wine 
applied to the brain and spinal marrow increased it. 
The admission of air into the cavity of the abdomen throws 
the bowels into strong spasmodic action, which alone would 
obscure any effect that can be supposed to arise from stimu- 
lating the brain. To remove this cause of failure, the abdomen 
