STOMACHAL DIGESTION. 247 



E. Corvisart), by long decoction in Papin's digester; the 

 same process with white of egg yields raetapeptone, which 

 may be afterwards transformed by the stomach or by artifi- 

 cial gastric juice into genuine peptones. Peptones have also 

 been produced by the action of ozone on the albumen of an 

 egg and on casein (Gorup-Besanez, Schiff), but for this 

 purpose the ozonized air must be made to pass during six- 

 teen to twenty days through a solution of albumen and 

 water; and this process, after all, yields only products resem- 

 bling peptones ; if injected into the veins of an animal, some 

 of them will reappear in the urine (Schiff). 1 



If we study the phenomenon of gastric digestion as a 

 whole, we no longer find in it, element by element, the simple 

 action which we have been examining: we know that the 

 amylaceous substances continue to be transformed into sugar 

 by the action of the saliva. The fats become slightly emul- 

 sive under the influence of the motions of the stomach, 

 and by mingling with the crumbled product of the solid 

 albuminoids ; but this emulsion is extremely unstable, and the 

 drops of fat show a tendency to reunite in large masses, 

 which float on the surface of the liquid. The different 

 albumens are transformed into different peptones, but there 

 are some kinds which for a long time resist the action of the 

 gastric juice : such as the cellular tissue of the muscles: and 

 some, finally, as the cellulose of plants, which are almost 

 refractory. The mingling of these different substances with 

 a large quantity of gastric juice forms what has also been 

 called chyme. But we see here, too, that the chyme is not a 

 substance immediately formed, but an extremely complex 

 pulp, and not at all fitted to give an exact idea of the diges- 

 tive action of the stomach. 



Attempts have been made to decide on the quantity of 

 gastric juice necessary to dissolve an aliment. In artificial 

 digestion a large quantity is required : thus one part of con- 

 crete albumen requires twenty-five parts of the juice ; the 

 quantity secreted is, therefore, very abundant, and is esti- 

 mated by litres: in man, for instance, it may be twenty litres 

 in twenty-four hours. The usual standard in animals is one 

 hundred grammes of gastric juice to one kilogramme of the 



1 See Cl. Bernard, " Lesons sur les Proprietes Physiologiques 

 et les Alterations Pathologiques des Liquides de 1'Organisme." 

 Paris, 1859. 



Blondlot, " De la Maniere d'agir du sue Gastrique." (Gazette 

 Medicale, 1857.) 



