through into thfe duodenum, thfe accumulation of cuyme that consequently fakes plac 

 in that direction, tends to propel the less soluble portions towards the cardia ; where, 

 according to the state of the organ, it may produce cardialgia, acrid eructations, or even 

 rumination. 



In the debilitated state of the stomach, and consequent deficiency of the secretions, 

 digestion can be perfectly performed only when the aliments are presented to it in 

 small quantity, and in a favourable state of complete comminution and intermixture 

 with the salivary juices, If, however, in this condition of the organ, the food is con- 

 veyed rapidly into it, possessed of neither of these requisites, so as to produce sudden 

 distension, a re-action of this viscus upon its contents takes place ; and, as the imper- 

 fectly masticated food constitutes the greater portion of the ingesta, there is abundance 

 present to be returned into the cardia and to be regurgitated, while there is a defi~ 

 ciency of aliment in a fit state to combine with, or to be operated upon, by the gastric 

 juices ; this when converted into chyme, is rapidly conveyed to the other extremity of 

 the organ, by the re -action of the muscular coat, arising from undue distension and the 

 stimulus of solid contents. Thus a double effect is produced by the healthy organic 

 contractility of this viscus, when in a weakened state, and yielding a diminished quan- 

 tity of the usual fluids, which state, indeed, rnay be considered as constituting this pecu- 

 liar affection, namely, the part of the aliment which is dissolved by the gastric juices 

 is conveyed toward the pylorus, whilst the tonic action of the stomach tending to di- 

 minish its capacity, pushes the less comminuted and indigestible portions of food into 

 the unresisting cardia ; whence they are returned, as we have described, in order to 

 undergo a second comminution and intermixture with the salivary juices ; after which 

 they are in a fit state to be conveyed to their destination along the mucous surfaces, 

 with the juices of which they combine, and thus permit a central portion of the mass to 

 return and undergo a similar process. 



Of the Influence ofthefineumo-gastric Nerves in Digestion* 

 Note L. 



The experiments of Dr. Phillip, although they by no means warrant the inferences 

 Which he deduced from them, show that the eighth pair of nerves conveys the influ- 

 ence of the cerebro-spinal system to the stomach, and re-intbrces and stimulates tha 

 vital energy bestowed on it by the ganglial system.' This conclusion is farther sup- 

 ported by the experiments lately performed at Paris by Breschet, Edwards and 

 Vavasseur. The inferences, which these physiologists have drawn from their experi- 

 ments, are 



1st. Simple section of the pneumo-gastric nerves in the region of the neck, without 

 loss of substance, and without separating the cut extremities, does not prevent diges- 

 tion from taking place, but merely retards it in an evident manner. 



2dty. Section of these nerves, with loss of substance, diminishes considerably, and 

 much more than simple section, the digestive action of the stomach, but it does not ap- 

 pear to abolish it completely. 



3dly. Section, or destruction of part of the spinal marrow, or removal of a portion of 

 the brain, acts in the same manner on the changes which the food undergoes in the sto- 

 mach. 



4thly. Narcotics, administered so as to produce coma, equally dimmish the energy 

 of the digestive powers. 



Sthly. It results, consequently, that every thing which diminishes the amount of ner- 

 vous influence, transmitted to the stomach, weakens the digestive action. 



6thly, and finally. When digestion is almost completely suspended by the section, 

 \vith loss of substance, of the pneumo-gastric nerves, the digestive action of the sto- 

 mach may be re-established, and the food contained therein be converted into chyle, by 

 means of the galvanic influence, with almost as much rapidity, and as perfectly, at least 

 in appearance, as under ordinary circumstances. {Archives generates, de Medicine, 

 .Aw*. 1823.) 



When the connexions of the different orders of nerves which supply the stomach arc 

 considered, and the intimate relation consequently subsisting between this organ and 

 the centres to which these nerves respectively belong, it cannot for a moment be 

 doubted that the interruption of the channel, through which this connexion takes 

 place, should be followed by a deranged stale of the functions depending thereon. Al- 



