Digestibility of Food. 519 



of apple and in one case by a solid food in the shape of gluten crackers and 

 shredded wheat. After fasting experiment No. 77, the subject did not remain 

 in the chamber and his diet for that day taken outside of the chamber was 

 chosen at will. During the day he consumed milk, bread, tomatoes, lemons, and 

 oranges, but the total quantity of food ingested was small, furnishing but 43.47 

 grams of protein, and 1311 calories of energy (see table 176). On the next 

 day the quantity of protein and energy was more than doubled, while on the 

 third day, the subject consumed 120 grams of protein and 3649 calories of 

 energy. The food experiments inside the respiration calorimeter which fol- 

 lowed certain of the fasting experiments, formed only a transitional period 

 from fast to complete food, inasmuch as the diet consumed was generally lim- 

 ited, especially as regards protein. Thus, in experiment No. 76, the food fur- 

 nished but 37.6 grams of protein and 1841 calories of energy per day, and while 

 the energy was sufficient to meet the requirements of the body during the inac- 

 tive period in the calorimeter, the protein was not sufficient to equalize the 

 draft upon body protein. 



On the first day after food experiment No. 76, i. e., the fourth day after the 

 end of the fast, the subject consumed a diet furnishing 131.5 grams of protein 

 and 5064 calories of energy, and on the following day, the amounts were even 

 larger, i. e., 167.5 grams of protein and 6612 calories of energy. 



While, therefore, the subjects were unable to consume large amounts of 

 food on the first day after fast, there seemed to be no difficulty in ingesting 

 large quantities on the second day. This is especially noticeable on the second 

 day after experiment No. 77, as has been pointed out above. 



THE DIGESTIBILITY OF FOOD AFTER INANITION. 

 The experiments with food which followed the fasting experiments in the 

 respiration calorimeter furnish some data regarding the digestibility of food 

 material after fasting. It is conceivable that after a long period of rest the 

 stimulus due to the ingestion of food would result in an excessive flow of the 

 digestive juices and increased peristalsis, and in an expulsion of feces from 

 the colon. On the other hand, the quantity of fecal material required to 

 distend the colon before defecation might result in a delay in the expulsion of 

 feces. The feces from ordinary digestion experiments are preceded by feces 

 of a character not especially different from those to be analyzed. Thus, 

 separation between the experimental feces and those resulting from the food 

 preceding is not based upon physical condition. Eegularity in the time of 

 meals and the amounts taken is also of importance in securing uniform con- 

 sistency of the feces. The irregularity in the ingestion of food, especially on 

 the first day following fasting, is one of a number of factors which tend to 

 hinder the accurate separation of feces. The small amounts of food ingested 

 on the first day, in some instances containing only 38 grams of protein, 



