A. W. W., April 6, 1907

Essentially the same amount of food was taken in this experiment as in that on the preceding day with A. H. M., i. e., 755 grams, with a total nitrogen content of 34.67 grams. The results, including the data for the nitrogen excretion, are given in table 199. The basal values used were averages of the results obtained in two experiments made from 2 to 3 weeks previous to the experiment with beefsteak. A noticeable increase in carbon-dioxide production occurs in all periods, the maximum amount being obtained in the third period. The maximum oxygen consumption appeared in the second period, while the maximum heat production was found in the fourth period. The course of the respiratory quotient was somewhat irregular. Since there are material increases in the fourth period, it is evident that here again we have not obtained the total effect of the food upon the metabolism in the 8 hours of the experimental period, and the experiment is therefore incomplete in this respect. It was of course possible to have made the experiment of 24 hours' duration, subdividing it into three 8-hour periods, but the main purpose of our experimenting was to study the maximum effect in the earlier stages of digestion, and the data are sufficient for this purpose. Thus we find that the maximum increment for carbon-dioxide production was 26 per cent, for oxygen consumption 39 per cent, and for heat production 24 per cent. One anomalous value appears in the results - that is, the slightly negative value found for heat production in the first period. This may be taken as essentially the basal value, although undoubtedly an error in direct calorimetry may have accounted for the fact that no increment was noted. The general picture shown in these results is not unlike that of the preceding experiment, namely, a decided increase in all of the factors of the metabolism. The fact that the high increments continued even into the last period indicates that the effect of food ingestion had not begun to decrease at the end of the experiment.

Table 199. - A. W. W., April 6, 1907. Sitting. (2-Hour Periods). Beefsteak

Amount, 755 grams; nitrogen, 34.67 grams; total energy, 1,571 cals.

Fuel value: Total, 1,268 cals.; from protein, 70 p. ct.; from fat, 30 p. ct. Basal values (March 15 and 21, 1907): CO2, 50 grams; O2, 41 grams; heat, 155 cals.

1Subject ate beefsteak in 54 minutes.

2Sample included amount for about 1 hour following the eating of beefsteak.

A. H. M., May 24, 1907

Approximately half the amount of beefsteak used in the experiment with this subject on April 5, 1907, was taken in the second experiment, the amount in this case being 384 grams, with a nitrogen content of 17.63 grams. The basal values used in the first experiment were likewise employed here. The data regarding metabolism, together with those for nitrogen excretion, are given in table 200. An increase in carbon-dioxide production, oxygen consumption, and heat production occurred in the first three periods, with a return to the basal metabolism in the fourth period. We doubtless have here, therefore, the total effect of the ingestion of this amount of beefsteak. The maximum increment occurred in the second period with all three factors, the percentage maximum for carbon-dioxide production being 27 per cent, for oxygen consumption 20 per cent, and for heat production 16 per cent.

Table 200. - A. H. M., May 24, 1907. Sitting. (2-Hour Periods). Beefsteak

Amount, 384 grams; nitrogen, 17.63 grams; total energy, 799 cals.

Fuel value: Total, 644 cals.; from protein, 70 p. ct.; from fat, 30 p. ct. Basal values (March 6 and 9, 1907): CO2, 51 grams; O2, 46 grams; heat, 164 cals.

1Subject ate beefsteak in 1 1/2 hours.

2Heat eliminated corrected for change in body-weight, but not for change in body-temperature. 3Sample included amount for about 1/2 hour without food and for 1 3/4 hours with food preceding this period.

A. W. W., May 25, 1907

Although made with a different subject, this is essentially a duplicate of the experiment on May 24, 1907, as the amount of beefsteak ingested (373 grams) is practically the same in both experiments and approximately one-half the amount eaten by A. W. W. in the experiment on April 6, 1907. The nitrogen content of the food was 18.62 grams. The results are given in table 201, and show the same general picture as the data given in table 200, i. e., an increment in the first three periods with a return to the basal metabolism in the fourth period. A singular fact to be noted is that the maximum effect for all three factors was observed in the third period, although this immediately preceded the return to the basal level. The total increment in carbon-dioxide production was 20 grams, in oxygen consumption 32 grams, and in heat production 45 calories. The total increment in heat production is much less than that found in the comparison experiment with A. H. M.; the increments for carbon-dioxide production and oxygen consumption also vary considerably in the two experiments. From the results of these experiments it is evident that the ingestion of approximately 375 grams of beefsteak results in an increased metabolism which is essentially completed at the end of 6 hours, as the values obtained for the last 2-hour period of both 8-hour experiments indicate that the basal level for the metabolism had again been reached.

Table 201. - A. W. W., May 25, 1907. Sitting. (2-Hour Periods). Beefsteak

Amount, 373 grams; nitrogen, 18.62 grams; total energy, 1,144 cals.

Fuel value: Total, 981 cals.; from protein, 49 p. ct.; from fat, 51 p. ct. Basal values (March 15 and 21, 1907): CO2, 50 grams; 02, 41 grams; heat, 155 cals.

1Subject ate beefsteak in 23 minutes.

2Heat eliminated corrected for change in body-weight, but not for change in body-temperature.

3Sample included amount for about 1 hour preceding eating of beefsteak.