632 JOHN K. MUKLUST 



nourishment has been resorted to, the infant's tissues are depleted of 

 glycogen at 2 days just as are those of an adult after several days of 

 fasting, and anything less than a large feeding of carbohydrate is held 

 up by the tissues to satisfy their craving for storage glycogen. 



2. Basal Metabolism in the Newborn. Carpenter and Murlin found 

 the metabolism of the newborn taken per unit of weight to be two and a 

 half times that of the mother lying in bed beside the child. Later observa- 

 tions by Benedict and Talbot (&) and by Bailey and Murlin make the figure 

 for newborns less than a week old 1.75 and 1.87 calories respectively per 

 kilogram and hour as against 1.0 calory per kilogram and hour for the 

 normal adult. The figure given by Benedict and Talbot is the average of 

 observations on nearly one hundred subjects which ranged from two and a 

 half hours to seven days of age, and had an average age of two days. 

 That given by Bailey and Murlin is the average of twelve hourly periods 

 on four infants less than one week of age, during which the infant slept 

 all or substantially all of the time. On the basis of twenty-four hours 

 at the same rate, the metabolism would be 42 calories per kilogram 

 according to Benedict and Talbot, or 45 calories per kilogram and 

 twenty-four according to Bailey and Murlin. It should be noted, however, 

 that the periods selected for this average represented the periods of unusual 

 muscular repose, and that no infant would ever actually maintain a 

 metabolism so low for an entire twenty-four hour period. It avoids con- 

 fusion, therefore, to report all results of metabolism experiments done in 

 short periods on the hourly basis ; for it is obvious that when a child sleeps 

 quietly for the entire period, as it did in most instances in the two series 

 of experiments referred to, the metabolism obtained does not represent 

 an average condition for the entire twenty-four hours. In fact, it would 

 be next to impossible to find a short, period or to arrange conditions for 

 one which could be said to represent average conditions for twenty-four 

 hours. Moreover, a child does not metabolize materials in periods of 

 twenty-four hours as an adult may be said on certain grounds to do. If 

 there is any cycle of metabolism in the newborn, it corresponds to the 

 feeding period. 



The influence of weight on the metabolism per unit of weight is well 

 illustrated by the table on page 633 from Bailey and Murlin. The 

 metabolism is noticeably higher for a light-weight baby (W, birth-weight 

 6 Ibs.) than for a heavy baby (B, birth-weight 10 Ibs. 3 oz.). From 

 considerations which will be presented in discussion of metabolism of older 

 infants, it is practically certain that the principal factor responsible for 

 such a difference is the insulating effect of subcutaneous fat or of the 

 effect of fat to reduce the effective radiating surface. 



The average heat production of all of the infants over' 4.00 kilos 

 body weight and over one day of age in Benedict and Talbot j s(&) Table 12 

 (loc. cit. p. 95) is 1.75 calories per kilogram and hour, while the average 



