278 FOOD INGESTION AND ENERGY TRANSFORMATIONS. 



for the total increments computed from the basal values and the values 

 measured after the ingestion of the food are much larger than in the 

 two preceding experiments with the same subject and with essentially 

 the same protein intake. The chief value of the results of this experi- 

 ment lies in the fact that they show the highest effect to be found in 

 the first few hours after the ingestion of food. 



BEEFSTEAK AND POTATO CHIPS. 



As it was somewhat difficult for the subjects to eat beefsteak alone, 

 approximately 20 grams of potato chips were taken in a few of the 

 Boston calorimeter experiments. The potato chips contained a con- 

 siderable proportion of fat and about the same amount of carbohy- 

 drate. 1 The carbohydrate thus added to the diet was not sufficient 

 to affect the measurements appreciably and, in view of the relatively 

 large amount of fat in the beefsteak, it was assumed that the addi- 

 tional fat in the potato chips would play but a small part in the total 

 metabolism. The five experiments in this series were made between 

 January 17 and May 11, 1911, the amount of beefsteak ranging from 

 193 to 272 grams. These experiments continued for 3 hours after the 

 food was ingested. Thus the total time for the preceding basal ex- 

 periment and the food experiment was about 8 hours, which was as 

 long as it was practicable for the subjects to remain quiet. In all 

 cases the measurements were made in periods of 45 minutes. It 

 was subsequently decided that observations of this length with the 

 calorimeter did not give results with a sufficient degree of accuracy 

 and their use was discontinued in later experimenting. Except in the 

 experiment with J. J. C. on May 11, 1911, the basal values for this 

 series of observations were determined on the same day as the meta- 

 bolism subsequent to the ingestion of the beefsteak and potato chips. 

 Truly comparable values were thus obtained. Statistical data not 

 included in the tables or in the discussion of the experiments are 

 here given: 



J. J. C., 9 h %4 m a. m. to S h 37 m p. m., January 17, 1911. 64.9 kilograms. 

 3 basal periods. Low-carbohydrate supper preceding day. Basal periods 

 ended Il h 42 m a. m.; food periods began 12 h 37 m p. m. Went to sleep at begin- 

 ning of first basal period, but was wakened 20 minutes after period had begun; 

 very quiet all of this period, reading when awake. Quiet for most part in 

 second basal period, dozing slightly once. Very quiet in last basal period, also 

 in first, second, and third food periods, and slept part of time in third food 

 period. More wide-awake in last food period than previously and very quiet, 

 especially at end. Urinated 7 a. m., Il h 04 m a. m., and 3 h 50 m p. m. ; went 

 through motions of urinating each period, usually near beginning of period. 

 Basal periods: pulse rate, 62; respiration rate, 17. Food periods: pulse 

 rate, 64; respiration rate, 17. 



J. J. C., 12*lo m p. m. to 6 h lo m p. m., May 11, 1911. 64.6 kilograms. Very 

 quiet throughout experiment, sleeping greater part of time. Moved consider- 



p. 258 and table 50. 



