102 PHYSIOLOGY OF THE NEW-BORN INFANT. 



By reference to table 12, it will be seen that the value of 866 calories 

 is over 100 calories higher than the highest value there recorded, for 

 only 3 observations are above 700 calories per square meter of body- 

 surface, these being obtained with infants 17, 27, and 81, who had a 

 heat-production per square meter of 713, 703, and 732 calories, respec- 

 tively. The average minimum heat-production of 612 calories per 

 square meter is 254 calories less than the minimum figure of Schloss- 

 mann and Murschhauser. 



Perhaps no better illustration than this can be found of the difficul- 

 ties of securing accurate information regarding the probable trend 

 of the metabolism of any group of individuals, in which one case 

 that was carefully and continuously studied gave a value of 866 calories 

 per square meter of body-surface, and a later research, in which 100 

 or more cases were studied, gave results very much lower, no value 

 being secured within essentially 130 calories of the minimum obtained 

 by the previous investigators. The cause for this discrepancy may 

 readily be found, we believe, in the inherent difficulties in obtaining 

 minimum metabolism measurements when the experimental periods 

 must of necessity be of several hours duration, as was the case with 

 Schlossmann and Murschhauser. Had these observers been able to 

 measure the metabolism of their infant in selected half-hour periods, 

 we have no doubt that their value of 866 calories would have been 

 materially reduced. 



The value of 866 calories reported by Schlossmann and Murschhauser 

 was not obtained with a new-born infant, but at the time their observa- 

 tions were published it was the general impression among pediatricians 

 that the metabolism of the new-born infant would be even higher per 

 unit of surface than that of an infant several months old. Accordingly, 

 the difference between our average minimum value of 612 calories and 

 the minimum value of Schlossmann and Murschhauser of 866 calories 

 per square meter of body-surface is, to say the least, most striking. 



It should likewise be borne in mind that it is impractical to use here for 

 comparison the heat-production per square meter per 24 hours recorded 

 for the infants studied in our previous research, 1 for these latter include 

 a large number of atrophic infants whose metabolism is admittedly 

 above normal. Although our material is slowly accumulating for an 

 estimation of the metabolism of perfectly normal infants from the time 

 of birth to the age of 2 years, we are not yet in a position to draw con- 

 clusions that will necessarily withstand subsequent addition of data; we 

 prefer, therefore, to defer the making of general deductions until later. 



INFLUENCE OF AGE UPON THE KATABOLISM. 



A general inspection of the values given in table 12 indicates that in 

 the first week of life there is some connection between the age and the 



Benedict and Talbot, Carnegie Inst. Wash. Pub. No. 201, 1914; also, Am. Journ., Diseases 

 of Children, 1914, 8, p. 1. 



