240 
DIGESTION. 
ordinarily used, I will not presume to decide ; but I offer the 
foregoing results to the profession, persuaded of their im- 
portance and interest in studying the application and 
physiological action of oils on the animal system.” 
Lancet , Nov, 5, 1853. 
DIGESTION. 
Influence of the Pneumogastric Nerves on Digestion . — Bidder 
and Schmidt have instituted a series of experiments (four in 
number) to determine the influence of the pneumogastric 
nerves on digestion, two of which were performed on dogs 
in whom gastric fistulae had been formed. They found that 
— 1. Section of the vagi did not diminish the sensation of 
hunger, and increase that of thirst. The oesophagus being 
paralysed , however , in its lower part, by the section of the vagi in 
the middle of the neck, the food or saliva swallowed could 
not pass into the stomach, and was again rejected. The 
absence of the usual endosmose of fluid and saliva into the 
blood explained the thirst. 2. The motions of the stomach were 
not impeded : they could be felt by the finger introduced into 
the fistula, and food passed into the fistula was forwarded in 
the usual way , and did not return with the vomiting which was 
going on. Thus the vagus does not possess (in the neck) 
those fibres by which the muscular coat of the stomach is 
connected with the centre of its regular actions. Never- 
theless, irritation of the vagus in the neck excites the action 
of the stomach. 3. The secretion of the gastric juice was 
little diminished . When any diminution occurred it was to 
be attributed to the lack of the stimulus of food from para- 
lysis of oesophagus. In consequence of the continued excre- 
tions of the animal, a lack of the necessary water for the 
preparation of the gastric secretion occurred, and its elimina- 
tion diminished considerably, but rose again as soon as the 
surface of the alimentary canal was artificially moistened. 
The gastric juice formed under a general deficiency of fluid 
was far less acid than that furnished after a new supply of 
water. This, however, which in one case was observed to 
rise continuously till the time of death, differed little from 
the reaction before the operation, being, on an average, 
neutralised by 413 gr. of potash per cent. Thus the chemical 
constitution of the gastric fluid is not remarkably altered by 
section of the vagi. 4. Finally, it is proved that the quantity 
of albumen digested is materially diminished by section of the 
