CHYMIFICATION. 595 



More recent experiments by Messrs. Wilson Philip, 1 Breschet, Milne 

 Edwards, and Vavasseur, 2 have shown, that the mere division of the 

 nerves, and even the retraction of the divided extremities for the space 

 of one-fourth of an inch, does not prevent the influence from being 

 transmitted along them to the stomach; but that if a portion of the 

 nerve be actually removed, or the ends folded back, chymification is 

 wholly or partly suspended. 3 Most of the experimenters agree with 

 Sir Benjamin Brodie in the opinion, that chymification is suspended 

 owing to the secretion of the gastric juice having been arrested by the 

 division of the nerves under whose presidency it is accomplished. MM. 

 Breschet and Milne Edwards, however, conceive, that the effect is 

 owing to paralysis of the muscular fibres of the stomach produced by 

 the section of the nerves; in consequence of which the different por- 

 tions of the alimentary mass are not brought properly into contact 

 with the coats of the stomach, so as to be exposed to the action of its 

 secretions; and they affirm, that when the galvanic influence is made 

 to pass along the part of the nerve attached to the stomach, its effect 

 is to restore the due action of the fibres; and, that a mechanical irri- 

 tant, applied to the lower end of the divided nerves, produces a similar 

 kind of change on the food in the organ; from which they conclude, 

 that the use of the par vagum, as connected with the functions of the 

 stomach, is to bring the alimentary mass into necessary contact with 

 the gastric secretions. These experiments were repeated in London by 

 Mr. Cutler, under the inspection of Dr. Philip and Sir B. Brodie ; but 

 the effects of mechanical irritation of the lower part of the divided 

 nerve did not correspond with those observed by MM. Breschet and 

 Milne Edwards. 4 



The experiments of F. Arnold, 5 and of MM. Bouchardat and San- 

 dras 6 lead them also to infer, that the nerves of the stomach appear to 

 influence chymification in so far as the process depends upon the 

 various motions of the organ. 



M. Longet 7 has endeavoured to reconcile these discordant results. 

 Having opened many dogs, he ascertained, that in the greater number, 

 irritation of the pneumogastric nerves induced contraction of the 

 stomach. Frequently, during his experiments, he saw the stomach 

 assume the hour-glass form. In a few dogs, the movements of the 

 stomach, on the irritation of the nerve, were scarcely perceptible. After 

 repeating his experiments on forty dogs, he recognised that the differ- 

 ence in the results obtained depended on the condition of the stomach 

 itself. Thus, if the animal was opened when it was full, irritation of 

 the pneumogastric nerves caused manifest movement; but, when empty, 

 scarcely any was excited: the movements, in fact, were feeble in pro- 



1 Philos. Transact, for 1822. 2 Archives Generates de Med., Aout, 1823. 



3 Ware, North American Medical and Surgical Journal., Philad., 1848. 



4 Bostock's Physiology, 3d edit., p. 523, London, 1836. 



5 Lehrbuch der Physiologic des Menschen, Zurich, 1836-7 ; noticed in British and Foreign 

 Medical Review for Oct., 1839, p. 478. 



Annuaire de Therapeutique, pour 1848, p. 283, Paris, 1848. 



7 Comptes Rendus, Fevr., 1842. See, also, Bischoff, in Mailer's Archiv., Berlin, 1843, and 

 Prof. E. Weber, art. Muskelbewegung, in Wagner's Handworterbuch der Physiologic, 15te 

 Lieferung, s. 41, Braunschweig, 1846. 



