314 DIGESTION. 



which a scale of the relative digestibility of different articles of food 

 might be made out. And even if all the conditions were similar, 

 a doubt would always remain as to the precise moment at which 

 gastric digestion might be said to terminate. There can be no 

 definite rule regarding the beginning of digestion, for the solvent 

 process commences as soon as the gastric juice comes in contact 

 with the object to be digested : if, for instance, we allow albumen 

 which has been previously carefully rinsed with acetic acid to 

 remain only five minutes in the stomach, a careful weighing will 

 generally (although not always) indicate a loss, which in this case 

 can only depend on actually digested albumen; a portion is, there- 

 fore digested in the course of five minutes, or, at all events, a 

 quarter of an hour, which shows that albumen obviously may be 

 digested in so short a time. We find, however, that when coagu- 

 lated albumen is introduced in considerable quantity into the 

 stomach, remains of it may sometimes be detected in that organ, 

 even after five hours ; as we cannot regard the commencement of 

 the process as affording a measure of the digestibility, the termina- 

 tions may probably serve this purpose. But even the end cannot 

 be always accurately determined ; for while one part of the albu- 

 minous body commonly leaves the stomach in an undigested state, 

 another often remains for a long time in the stomach, in conse- 

 quence of the digesting force of that organ becoming gradually 

 weakened, and its glands secreting less juice after it has been for 

 some time in a state of functional activity a circumstance which 

 more than any other, is dependent on the individual constitution. 

 In many animals, however, the stomach is never altogether empty, 

 as for instance, in the rabbit. Even when these animals perish 

 from hunger, the remains of their last meal may still be found in 

 the stomach. Although this is not the case with the carnivora and 

 omnivora, it shows that the termination of gastric digestion and 

 the emptying of the stomach cannot furnish any appropriate 

 standard for the determination of the digestibility of a substance. 

 It might perhaps appear superfluous to devote so much space to 

 the consideration of a subject which is so simple of compre- 

 hension, but we must bear in mind these relations and the general 

 vagueness of the idea in question, before we can even attempt 

 to construct any scale of the digestibility of the simple and com- 

 pound articles of food, which could be of use for purely prac- 

 tical purposes. C. Schmidt has never found all the albumen 

 dissolved in the stomach, and after it had remained for six hours 

 inclosed in muslin bags, he constantly found that half of it was still 



