18 IS.] Imperial Institute of France. 309 



explain it. It was long ascribed to the muscular trituration of 

 the stomach ; but Reaumur having remarked that food contained 

 in incompressible tubes, open at the two ends, was digested like 

 other food, the general opinion since that time has been that the 

 food was dissolved by means of a juice secreted by the stomach. 



Spallanzani, in a very celebrated work, having applied the 

 gastric juice out of the stomach to every kind of food, affirmed 

 that it produced, when assisted by heat, effects nearly similar to 

 those produced in the stomach itself. This philosopher went so 

 far as to ascribe to this gastric juice, thus separated, the pro- 

 perty of stopping putrefaction. He drew this conclusion from 

 his observations, which has been tacitly adopted by most phy- 

 siologists, that the gastric juice produces its effects in conse- 

 quence of its peculiar nature, of its composition, and affinities. 



M. de Montegre, Doctor of Medicine, having the power of 

 throwing up, without inconvenience, what he has in his stomach, 

 has thought of employing this power in order to determine the 

 different points of the received doctrine respecting digestion. 

 When he throws up the contents of his stomach while fasting he 

 obtains a notable quantity of a liquid which he considers as true 

 gastric juice, and which he examined with respect to its che- 

 mical properties as well as its action on the food. 



He found this liquid very similar to saliva; but its action 

 appeared to him very different from the statement of Spallan- 

 zani. When exposed to a temperature similar to that of the 

 human body, in phials placed under the armpit, it putrefied 

 exactly like saliva. It did not stop the course of putrefaction 

 in other substances, except when it was acid ; and by adding a 

 little vinegar to saliva it was made to possess the same property. 

 This acidity is not essential; and when M. de Montegre swal- 

 lowed enough of magnesia to absorb it the digestion went on 

 as well as usual. Acidity appeared again in a little time: even 

 when M. de Montegre mixed the food which he swallowed with 

 magnesia it became acid-after a sufficient time. 



These experiments, repeated a great number of times, and 

 with all the requisite precautions, have induced the author to 

 . tout hide that the gastric juice does not differ from saliva, that 

 it cannot stop putrefaction, nor produce digestion independent 

 of the vital action of the stomach; and that the acidity which 

 appears, and which the food evolves during digestion, is an 



ct of the action of the stomach. 



It is much to be wished that M. de Montegre would continue 

 hi', reManh<"-, and make them also upon those animals that 

 N).;illanz;.ni employed, that \vc may determine what to think of 

 a doctrine which has lor a considerable time been generally 

 ( nihiaci (I 



i hat authors may be able to verify the date of their observa- 



2 



