94 
METABOLISM EXPERIMENTS NOS. 29 AND 31. 
Subject. — J. F. S., the same person as in experiments Nos. 25, 26, 
and 28, His weight, with underclothing', was about 64.5 kilograms 
(142 pounds). 
Occupation during experiment. — Worked 8 hours a day upon a sta- 
tionary bicycle arranged as an ergometer, as described on page 20. 
The voltage of the electric current generated was measured, and the 
average number of pedal revolutions per minute observed. The cur- 
rent generated was passed through resistance within the chamber and 
thus transformed into heat, which was measured with the heat given 
off by the subject. The actual amount of work done each day was 
found by determining the watts required to drive the bicycle ergometer 
at the rate maintained by the subject during the experiment. 
Duration. — Experiments Xos. 29 and 31 were the first and third 
of a series of 3, each of 3 days* duration. The intervening experiment 
is not reported here. The usual preliminary period continued •! days, 
beginning with breakfast March 12, 1900. On the evening of the 
fourth day. March 15, the subject entered the calorimeter. Experi- 
ment No. 29 began at 7 a. m. March 16, and ended at 7 a. m. March 19. 
Experiment No. 31 began at 7 a. m. March 22, and ended at 7 a. m. 
March 25. 
Diet. — The aim of this series of experiments was to study the rela- 
tive replacing power of isodynamic quantities of different materials 
when the subject was at active exercise. There was. as usual, a basal 
ration supplemented by different materials. This basal ration was the 
same in both experiments, with the exception of slight differences due 
to variations in the composition of the milk consumed. It furnished 
approximately 100 grams of protein and 2,980 calories of energy per 
day. To this ration was added 128 grams of cane sugar per day. fur- 
nishing 507 calories of energy in experiment No. 29. and 63.5 grams 
of butter per day, furnishing 1 gram of protein and 511 calories of 
energy, in experiment No. 31. The kinds and quantities of food 
served at each meal and the quantities of drink at different periods 
of the day were as follows: 
Table 111. — Diet in metabolism experiments Xos. 29 and 31. 
FOOD— BASAL RATION. 
Food materials. 
Breakfast. 
Dinner. 
Supper. 
Total. 
Beef .. 
Grams. 
Grams. 
58 
23 
300 
150 
25 
Gnms. 
Grams. 
58 
Butter 
12 
300 
75 
25 
37.5 
12.5 
12 
300 
75 
25 
37.5 
12.5 
47 
Milk, whole 
900 
Bread 
300 
75 
75 
25 
