244 STORRS AGRICULTURAL EXPERIMENT STATION. 



Fifty digestion experiments are here reported. These were 

 made with three different subjects ' all young ^ active, healthy men, 

 whose digestive powers were believed to be unimpaired. The 

 individual experime^its were generally three or foitr days in 

 letigth, though a few were only one day and one was eight days. 

 Eighteen of the experiments ivere carried on while the subjects 

 were outside the calorimeter, a7id thirty-two formed part of the 

 metabolisiJt experiments with the subjects in the respiration cham- 

 ber. The amounts of (external) muscular work performed by the 

 subjects ranged in different experiments from almost none to hard 

 zvork eight hours a day, and in one experifnent sixteen hours. 

 The diet zvas simple, and co7itained a 7iumber of common food 

 materials, both animal and vegetable. In eighteen of the studies 

 the quantities of the different n^itrients were about the same as in 

 ordijtary diet. In seveiiteen experitnents the diet contained large 

 quantities of fat, and in fotirteen large qicantities of carbohy- 

 drates, though the energy in these cases was not greater than was 

 required to satisfy the needs of the body under the conditio?is of the 

 experiments. 



No effect of individuality upon the availability of the nutrients 

 of the diet is evident. With each subject the range of variatio7i iyi 

 the results of similar experiments is much wider than the differ- 

 ences between the averages of similar experiments -with different 

 subjects. 



If the sojourn ivithin the calorimeter had any influeyice upo7i 

 the availability of the diet, it was to i7nprove it very slightly i7i 

 S07)ie cases; while i7i others there zvas 7io appare7it effect. The i7i- 

 dividual experi77ie7its shoiv considerable variatio7i i7i the residts 

 i7iside and outside^ the caloriineter, the availability bei7ig ivith the 

 same subject someti7nes larger a7id sometii7ies S7naller i7iside the 

 calori77ieter than outside. Co77ipari7tg the averages of the results 

 for all the preli77iinary periods for each subject with those for the 

 calori77ieter periods , the coeffi,cie7its were slightly laiger with E. O. 

 and f. F. S. duri7ig the latter period, bid withf. C. W. the av- 

 erage results were practically the sa77ie for the expe7'i7ne7its withi7i 

 the calorimeter as for those oidside. 



Increasing the qua7itity of either carbohydrates or fat above 

 those co77imo7i in the ordinary diet had no effect 2ipo7i the avail- 

 ability of the other 7iidrients of the diet, while the availability of 

 the fat or the carbohydrates i7i the experi77ie7its in which either 



