136 



GASEOUS METABOLISM OF INFANTS. 



the fact that only periods of complete muscular repose can logically be used 

 in discussing infant metabolism. 



In connection with the classification of the activity in the several periods, 

 it is of interest to compare estimates made independently by two persons 

 several weeks after the first estimate was made. This is done in table 29. The 



Table 29. — Comparison of original estimates of activity with later estimates made 

 independently by two individuals. 



(Observation with M. M., June 5. 1913.) 



•Preliminary period. 



only disagreements after several weeks, during which time several hundred 

 records had been examined, are found in the estimates for the second and 

 fourth periods in distinguishing between classifications I and II. No attempt 

 was made to classify the activities beyond V, any degree of activity beyond 

 this being classed as VI. While one might say that the activity in the last 

 period was two or three times that of the first period, since it is classified as 

 VI, this conclusion is not justifiable, as is shown by the records of the pulse- 

 rate and the metabolism in these two periods. 



Observation with F. K., May 2, 1913. 



Another infant, F. K., with a body- weight of 5.68 kilograms, showed activi- 

 ties ranging from I to VI in the kymograph curve for May 2, 1913 (see figure 

 48). No curve previously given has shown a perfectly smooth line for an 



■mrrrn 



— v-vWrn — 



~~ff 



-it»»~ 



■fN*" 



'»fr "n ~ 



F.K. 



MAY2.I9I3 



Fig. 48. Kymograph curve for F. K., May 2, 1913. 



entire period, but such a line was obtained in the second experimental period 

 of this observation, i. e., that from 3 h 39 m p. m. to 4 h l m p. m. Incidentally 

 this indicates how large an amount of experimental work must be done in order 

 to secure a sufficient number of periods with minimum activity for comparison. 

 Indeed, for the fundamental discussion of the comparative metabolism of 

 infants, hardly one-third of our entire series of observations could be utilized. 

 An interesting comparison of the total metabolism, the pulse-rate, and the 

 records of the activity for this observation is given in table 30. A general 

 uniformity is observed, although the preliminary period (from 3 h l m p. m. to 



