
EXPERIMENTS ON DIGESTION OF FOOD BY MEN. 169 
DESCRIPTIONS OF INDIVIDUAL EXPERIMENTS. 
Lxperiment No. 1.—Kind of food: Milk. Subject: Laboratory janitor. Age: 
28 years. ‘eight (without clothing): 67.6 kilos (149 lbs.). The experiment 
commenced with breakfast, October 23, 1894, and ended with dinner, October 
24, making 5 meals. 
The charcoal for the separation of the feces was taken with the milk of the 
first meal, so that the colored feces were included in the amount collected for 
analysis. The second separation was made with milk and charcoal for the next 
meal after the end of the experiment, z. ¢., for supper, October 24. The large 
weight of the feces suggests the idea that the first milk may flush the intestines 
so as to carry metabolic products or material with the feces which do not belong 
to the milk. This, if true, would account not only for the very large excretion, 
but also for the low digestibility of protein indicated. Asa matter of fact, the 
excretion for the first day was very large, and for the remaining time, two-thirds 
of a day, very small. The subject experienced no discomfort from his diet and 
performed his duties about the laboratory as usual. Since the results,do not 
appear to be entirely trustworthy, as indicating the proportions of nutrients 
digested, they are not included in the summary in table 53. 
Lixperiment No. 2.—Kind of food: Milk. Subject: Sameasin No.1. Weight 
(without clothing): 67.6 kilos (149 Ibs.). The experiment commenced with 
breakfast, October 29, 1894, and ended with dinner, October 31, making 8 
meals. ‘The separation of the feces was the same as in Experiment No. 1, and 
the same remarks apply. 
Experiment No. 3.—Kind of feod: Flour (as bread), and sugar. Szdzect: 
Same as in Nos. 1 and 2. Weight (without clothing): 67.6 kilos (149 Ibs.). 
The experiment commenced with breakfast, November 6, 1894, and ended with 
dinner, November 8, making 8 meals. The separation of the feces was made 
by means of milk and charcoal taken as the last meal preceding the commence- 
ment and the first meal after the end of the experiment, z. e., supper, November 
5, and supper, November 8. The division was made so that none of the col- 
ored feces were included in the portion analyzed. This is the usual method of 
separation and was followed in all subsequent experiments. The flour was 
made into bread, for which 1447 grams were used, with salt and baking powder, 
but without fat for ‘‘shortening.’”’ The resulting bread weighed 2312 grams. 
This experiment is defective in that the loss of material during the process of 
baking is left out of account. Late experiments* indicate that the loss of fat 
in the baking of bread may be very considerable. For this reason, and because 
of the very small amount of fat present even in the uncooked flour, as well as 
the doubtful accuracy of fat determinations by the ordinary methods, especially 
in feces, the figures for the digestibility of the fat are not given. 
Experiment No. 4.—Kind of food: Flour and milk. Swdzect.- The same as 
in the preceding experiments. Weight (without clothing): 67.6 kilos (149 Ibs.). 
The experiment commenced with breakfast, December 12, 1894, and ended with 
dinner, December 14, making 8 meals. The separation of the feces was made 
by milk and charcoal, as in experiment No. 3. Flour to the amount of 1500 
grams was made into 2436 grams of bread, as in the preceding experiment. 
The statements regarding the fat in the bread apply here as in experiment No. 3, 
but inasmuch as the fat of the flour or bread is so small in amount as compared 
with that furnished by the milk, the figures for the amount of fat digested are 
no doubt reliable. 

* See Bulletin No. 35, Office of Experiment Stations, United States Department of 
Agriculture, pp. 14 to 17. 
