VOMITING. 633 



tion of intestine, which acts more speedily than the injection of sub- 

 stances into the veins. The abdomen of a dog was opened, and a ligature 

 passed round a portion of intestine, which was returned into the abdo- 

 men, and the wound closed by suture: vomiting took place. All the 

 abdominal muscles were next extirpated, the skin, alone, forming the 

 parietes of the cavity. This was brought together, and the vomiting 

 continued. On another dog, three-quarters of the diaphragm were 

 paralysed by the section of the phrenic nerves. The abdomen was 

 now opened, and a ligature placed round a portion of intestine. Vomit- 

 ing occurred. Lastly; these two experiments were united into one. 

 The abdominal muscles were cut crucially, and removed ; the phrenic 

 nerves divided; and the diaphragm was cut away from its fleshy portion 

 towards its tendinous centre ; leaving only a portion as broad as the 

 finger under the sternum. The integuments were not brought together; 

 yet vomiting continued. 



As these results were obtained on numerous repetitions of the experi- 

 ment, M. Maingault conceived himself justified in deducing inferences 

 opposite to those of M. Magendie, namely, that the contraction of the 

 diaphragm and abdominal muscles is only accessory to the act of 

 vomiting; that the action of the stomach is its principal cause; that 

 the latter is not a convulsive contraction, which strikes the eye, but a 

 slow, antiperistaltic action ; and that the only convulsive movement is 

 the contraction of the oesophagus, which drags the stomach upwards. 

 He adduces, moreover, various considerations in favour of his deduc- 

 tions. If the stomach, he asks, be passive, why does it possess nerves, 

 vessels, and muscular fibres? Why is vomiting more energetic, when 

 the stomach is pinched nearer to its pyloric orifice? Why are the rugae 

 of the mucous membrane of the stomach, during vomiting, directed in 

 a divergent manner from the cardiac and pyloric orifices towards the 

 middle portion of the organ ? If the diaphragm does all, why do we 

 not vomit whenever that muscle contracts forcibly ? Why does not the 

 diaphragm produce the discharge of urine in paralysis of the bladder? 

 Why is vomiting not a voluntary phenomenon? And, lastly, how is it 

 that it occurs in birds, which have no diaphragm ? 



The minds of physiologists were of course distracted by these conflict- 

 ing results. M. Richerand 1 embraced the views of M. Magendie ; and 

 affirmed, that he had never observed contraction of the stomach ; and 

 that it seemed to him the least contractile of any part of the intestinal 

 canal. With regard to the experiments of M. Maingault, he con- 

 sidered, that the stomach had not been wholly separated from the sur- 

 rounding muscles; that the action of the pillars of the diaphragm, and 

 the spasmodic constriction of the hypochondres are sufficient to com- 

 press the viscus; that nothing is more difficult to effect than the section 

 of the phrenic nerves below their last root ; and, moreover, such section 

 does not entirely paralyse the diaphragm, as the muscle still receives 

 twigs from the intercostal nerves and great sympathetic ; that the car- 

 dia, being more expanded than the pylorus, the passage of substances 

 through it is rendered easy; and that it is incorrect to say, that the 



1 Nouveaux Elemens de Physiologie, 7eme edit., Paris, 1817, 



