DIGESTIBILITY OF BREAD. 1/9 



DIGESTION EXPERIMENTS WITH 1!R!:.\D. 



The experiments here reported were made in 1896 and 1897. 

 The subjects were young men with vigorous appetites and 

 apparently normal digestion. 



The food eaten. — The experiments began in each case with 

 a supper of milk, with which each subject took six gelatine cap- 

 sules filled with lamp-black. For the two days following the 

 food consisted chiefly of the bread under investigation. Butter 

 v.'as eaten with the bread, and the men were allowed milk and 

 coffee wuth sugar. On the morning following the second day 

 of the bread diet, the men again took lamp-black m capsules 

 and a breakfast of milk, no solid food being taken until noon. , 



No attempt was made to limit the amount of food taken. 

 The food of the men was kept separate. Whenever a new loaf 

 \\as needed, it was weighed and quartered, one quarter serving 

 for analysis. At the close of the experiment the food remaining 

 v/as weighed and the amount subtracted from that furnished. 



Feces. — The feces were deposited in a line in large tins pro- 

 \ ided for the purpose. That coming from the milk taken at the 

 beginning and end of the experiment, being deeply colored by 

 the lamp-black, was for the most part readily separated from 

 ihe feces coming from the bread diet. 



Urine. — As no marker can be used for urine, it was collected 

 for the two days of the bread diet, it being understood, of 

 course, that this does not correspond to the food taken during 

 that period. 



The tables which follow give the details of the digestion 

 experiments, the table on page 193 containing a summary of the 

 results. 



There is nothing in the table which requires explanation 

 unless it is the method of calculating the "per cent of energy 

 utilized." This is the same as used at the Storrs (Conn.) 

 Experiment Station and is described in the report of that 

 Station for 1894,* from which the following is quoted. 



"When protein is burned in the calorimeter it is completely 

 oxidized, the carbon being burned to carbon dioxide and the 



* Fuel values of cUgestetl nutrients in experiments with sheep, W. O. Atwatar 

 and Chas. D. Woods. 



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