OBSERVATIONS BY HASSELBALCH. 29 



utes. The experiment was made with the same male infant as experi- 

 ment 25 in table 4, the weight of the child being 3,600 grams and the 

 age 6 days. It was breast-fed. The temperature of the apparatus 

 was 25 to 26 C.; the body-temperature of the infant was 37.0 to 

 36.6 C. The percentage of carbon dioxide in the air of the chamber 

 was 1.534; the carbon-dioxide elimination per kilogram per hour, 

 reduced to C. and 760 mm., was 764 c.c. and the respiratory quotient 

 0.897. The child was crying violently three-quarters of the experi- 

 mental period and was evidently cold. In the middle of the experi- 

 ment there was a quiet period with a little sobbing. It would be 

 erroneous to consider the great increase in metabolism (compare 

 experiment 25, table 4) in this experiment a result of the child's' 

 " chemical heat regulation" brought about by a cold reflex. 1 The 

 infant would have reacted to any other equally powerful irritant with as 

 severe crying and with equally high metabolism. 



Even if the previous experiments leave no doubt that the carbo- 

 hydrates of the food play the same role in the infant's nutrition as in 

 that of adults, namely, that of the most accessible food elements and 

 consequently most quickly consumed for heat production, and even if 

 the results in table 4 are most easily interpreted on the supposition 

 that the absorption and metabolism of carbohydrates reach their 

 climax 1 to H hours after the meal, further experimental evidence is 

 still needed of the correctness of this hypothesis. With this purpose 

 in mind three infants were put on a diet so arranged that meals were 

 given between their regular feedings. These meals consisted of 4 to 5 

 grams of grape or milk sugar dissolved in a little water. 



In experiment 29 of table 5 the respiration experiment commences 3 

 hours after the milk meal and about 1^ hours after the lactose meal. 

 The quotient is 1.0. In experiment 26, in which the grape sugar was 

 given 4 hours and again one-half hour previous to the experiment 

 (breast-feeding between the two feedings about 2 hours previous to the 

 experiment), it is seen that the quotient 0.869 does not point towards 

 an exclusive carbohydrate metabolism. In the course of the half 

 hour the absorption of the administered grape-sugar has not taken place. 

 Finally, in experiment 31, undertaken about 3^ hours after the last 

 milk meal and about 1\ hours after the last grape-sugar feeding, the 

 quotient is 0.845, an index that the metabolism of the 4 grams of grape- 

 sugar has to a great extent taken place as quickly as %\ hours after admin- 

 istration. 



This result corresponds strikingly with those obtained by Speck and 

 Magnus-Levy with adults (my discussion of the results in table 4 were 

 based on the results obtained by these two authors), and with Mosso's 

 demonstration of a temperature rise of 1 C. in the case of a starving 

 dog, about an hour after the ingestion of an amount of sugar correspond- 

 ing to that used in these experiments. It is thus clear that the custom 

 of feeding sugar-water immediately after the birth-bath rests upon a 



(Archiv f. d. ges. Physiol., 1902, 89, p. 166) interprets a rise in metabolism from 332 

 c.c. to 579 c.c. carbon dioxide as a sign of an "auffallige Thiitigkeit der chemischen Regulation," 

 without giving information about the child's behavior in the two cases. 



