640 JOHN K. MUKLIISr 



higher. Since, however, the period of crying continues for the normal 

 newborn rarely more than a few hours at most, the additional allowance 

 of food energy should not he computed on a 24-hour basis, but an attempt 

 should be made to estimate the total period of crying. 



The energy allowance for growth cannot yet be estimated with any 

 accuracy. In general it may be stated only that any energy left over 

 after the basal and activity metabolism are provided for will be available 

 for growth, since, so far as we can see at present, no allowance is necessary 

 for dynamic action or for fluctuations of external temperature. 



It would appear from the foregoing that an energy supply of 2.5 cal- 

 ories per kilogram per hour or 60 calories per kilogram and 24 hours, 

 will amply cover the maintenance requirement of newborn infants who 

 are not more than normally active. Any intake beyond this amount may, 

 it is presumed, be counted upon to furnish materials for growth. Further 

 study of the "growth quota" in infants of this age, however, is very much 

 needed. 



G. Energy Metabolism from Two Weeks 

 to One Year of Age 



The energy metabolism of infants over two weeks of age has been 

 much more extensively studied. Beginning with the fragmentary ob- 

 servations of Forster in 1877 down to and including 1920, not less than 

 a score of important researches have been published on the normal child. 

 (Birk and Edelstein, Rowland (6), Kubner and Heubner(a, &_, c,), 

 Schlossmann and Murschauser (a, 5, c, d), Bahrdt and Edelstein, Frank 

 and Wolff, Murlin and Hoobler, Xiemann(a, c), Bonniot, Saint-Albin, 

 Variot and Lavialle, Hoobler(fr)). These fall into two groups according 

 to the method of observation adopted. The earlier researches by the in- 

 direct method were made for the most part upon a few individuals, but 

 these were studied very exhaustively with a view to account for all of the 

 food ingested. The later researches by the indirect method and all the ob- 

 servations upon normal infants by the direct method have sought rather to 

 establish standards of metabolism with which abnormal or pathological 

 cases could be compared. Consequently a considerable number of sub- 

 jects have usually been employed. Several of the investigators have se- 

 lected from their own cases those whom they consider normal. In the 

 case of some others it has been necessary to select from the published tables 

 whom the authors describe as of normal weight for age. 



1. Respiratory Quotient. Very little need be added to what was said 

 under this heading for the newborn. Carbohydrate is the food which in- 

 fluences the quotient most. Soon after a feeding of milk, whether breast 

 or cow's milk, the quotient will be found higher than just before, provided 



