INGESTION OF CARBOHYDRATES. 233 



vals and measured periods by the respective increments per minute 

 resulted in totals of either carbon dioxide produced or oxygen absorbed. 

 The totals for periods and intervals, when added together, gave the 

 amounts for the total period in which increment was observed. The 

 computation of the increment began with the time when the subject 

 had finished eating and continued to the end of the last period of the 

 experiment, or through the period in which the increment apparently 

 ceased. 



The experiment of December 31, 1912, in which the subject J. C. C. 

 took 100 grams dextrose, may be used to illustrate this method of com- 

 puting the increment (see table 127, page 206) . The basal value for car- 

 bon dioxide determined on the same day was 187 c.c. per minute. The 

 amount per minute measured in the first period beginning at Il h 13 m 

 a. m. was 196 c.c., or an increment of 9 c.c. per minute for the 14 min- 

 utes and 39 seconds of the period ; the total increment observed in the 

 period (14.65 X 9) is therefore 132 c.c. Between the time when the 

 subject finished eating and the beginning of this period there was an 

 interval of 8 minutes. Assuming for this interval an increment per 

 minute of one-half that observed in the first period, the total increment 

 for the preliminary interval (8 X 4.5) was 36 c.c. The increase in 

 carbon dioxide for the second period beginning at Il h 45 m a. m. was 16 

 c.c. per minute, the total for the period (14.92 X 16) being 239 c.c. 

 Between the first and second periods there was an interval of 17 min- 

 utes and 21 seconds; assuming a value equal to the average of the per 

 minute increments in the first two periods, the total increase in carbon 

 dioxide for this interval (17.35 X 12.5) was 217 c.c. The results for 

 the remaining periods and intervals are obtained in the same manner 

 and the total increase in carbon dioxide to the end of the sixth period 

 following the ingestion of dextrose was, therefore, the sum of the com- 

 puted and measured increments (36 + 132+217+239+316+315+396 

 +349+550+270+372+195) or 3,387 c.c. The equivalent of this 

 amount is 6.7 grams of carbon dioxide. For the same period of obser- 

 vation, i. e., through the period ending at 2 h 26 m p. m., the increment of 

 oxygen computed and measured was 3 grams and the increase in heat 

 obtained from the measured area of increment superimposed on the 

 fasting base-line was 12 calories. 



The total increments for each sugar studied are shown in tables 174 

 to 177. Although the maximum effect, as we have seen, was obtained 

 usually inside of the first 1| hours after the ingestion of the sugar, 

 there was a positive increment in carbon-dioxide production, oxygen con- 

 sumption, and heat production, which was measurable for a fairly long 

 period. Usually the increments in oxygen consumption and heat 

 production persisted for about the same length of time, and thereafter 

 basal values were obtained for both these factors. Frequently the 

 increment in the carbon-dioxide production continued for some time 



