DISCUSSION OF RESULTS. 



131 



standing the fact that considerable muscular activity immediately preceded 

 the beginning of the period. Up to 4 h 12 m p. m., there was no approach to a 

 condition of repose, but the period from 4 h 12 m p. m. to 4 h 42 m p. m. was the 

 quietest period of the observation. The activity about 4 h 41 m p. m. was taken 

 as indicating that the infant was waking up ; as this would naturally be accom- 

 panied by considerable activity, a new period was begun. In the last period, 

 that from 5 h 8 m p. m. to 5 h 38 m p. m., the curve is reasonably constant, the 

 regularity of the line being broken by five or six movements. As a rule, per- 

 fectly smooth lines could rarely be obtained with this infant. 



"* 1 



, •> M l > I —>t »- 



■■+ »'» 



— ^r 



-+ — » > — h 



1 " Jt ' 



-W-*f~ 



-y\jwvwvww 



J.V 



FEB.27.I9I3 



Fig. 43. Kymograph curve for J. V., February 27, 1913. 



An examination of the estimated muscular activity given in table 24 shows 

 that while it varied from III to VI, the estimates usually followed quite closely 

 the total heat output. Thus, the two periods characterized as III represent 

 238 and 233 calories per 24 hours respectively, the two periods marked V 

 correspond to 259 and 254 calories per 24 hours, and the preliminary period, 

 which shows the most activity (VI), corresponds to 281 calories per 24 hours. 

 The fluctuations in the pulse-rate are not very great in this particular observa- 

 tion, the minimum being 135 and the maximum 144; in general they follow 

 the muscular activity and the total heat-production. 



Table 24. — Comparison of the pulse-rate, metabolism, and muscular activity in 

 observation with J. V., February 27, 1913. 



•Preliminary period, 



A record of the sensitivity test is shown at the bottom of the kymograph 

 curve, and the amplitude of the excursion and the regularity of the vibration 

 vouch for the sensitiveness of the apparatus at that time. 



