BASAL KATABOLISM. 



103 



total katabolism. Although little in the nature of such a relationship 

 may be expected in the first hours after birth, for during the first 24 

 hours of life there must certainly be a profound readjustment of the 

 organism as a result of the radical change in environment, yet in order 

 that a study may be made of this possible relationship, three charts 

 have been plotted in which the total heat-production per 24 hours, the 

 heat-production per kilogram of body-weight, and the heat-production 

 per square meter of body-surface have been plotted against the age, 

 the minimum figures given in table 12 being used in all cases. (See 

 figures 7, 8, and 9.) 



INFLUENCE OF AGE UPON THE HEAT-PRODUCTION IN THE FIRST DAY. 



The total heat-production and the age in days at the time of measure- 

 ment are compared in figure 7, from which it will be seen that there is a 

 general tendency for the low values for the heat-production to occur 



Q 



Calories per 24 Hours 



FIG. 7. Minimum heat-production of new-born infants per 24 hours referred to age. 



on the first day of life. The chart does not take into consideration the 

 differences in body-weight, but this is done in figure 8, in which the 

 heat-production per kilogram of body-weight per 24 hours is plotted 

 against the age. In figure 8, also, we find that nearly all of the low 

 values, such as those under 40 calories per kilogram per 24 hours, 

 appear on the first day, even when the weight of the infant is taken 

 into account. 



This tendency is shown even more strikingly in figure 9, in which 

 the heat-production per square meter of body-surface per 24 hours is 

 plotted against the age, for all but 4 of the values below 600 calories 

 are found on the first day. It is likewise of interest to note that the 

 two highest values obtained with our infants for the heat-production 

 per square meter of body-surface per 24 hours were also found on this 



