136 METABOLISM AND GROWTH FROM BIRTH TO PUBERTY. 



TOTAL METABOLISM OF CHILDREN REFERRED TO AGE (EARLIER INVESTIGATORS). 



Since our study was made primarily to secure the metabolism under 

 conditions giving the basal metabolism, i. e., with the values unaffected 

 by muscular activity and with but little and preferably no influence 

 of food, it is important in comparing our results with those of earlier 

 writers to include of the latter only those obtained under conditions 

 approximating complete muscular repose. As shown in a considera- 

 tion of the previous literature on this subject (pages 4 to 21), 

 relatively few of the earlier values meet these conditions. For ex- 

 ample, all the studies of Andral and Gavarret 1 were made with the 

 children in the sitting position and the data obtained (see table 1, 

 page 5) indicate a total metabolism per 24 hours much higher at 

 the low ages than that found by us with either boys or girls. Such 

 values of the earlier studies as are suitable for comparison have, how- 

 ever, been charted, together with the lines showing the general trends 

 noted on our several charts. 



The values for the boy and girl studied by Scharling 2 can advan- 

 tageously be plotted, but the data for Forster's 3 children are averaged 

 in such a way that it would be difficult to apply them on our charts. 

 For example, he finds no material change in the carbon-dioxide pro- 

 duction per 10 kg. with children throughout the period from 3 to 7 

 years of age, namely, 11.7 grams per 10 kg. per hour, or approximately 

 3.50 calories per kilogram per hour. Since no data as to the body- 

 weight are given, it is impossible to plot his values on our charts, but 

 those given for children from 3 to 7 years of age correspond to about 84 

 calories per kilogram per 24 hours, which is far in excess of values 

 noted by us for any age. This high metabolism is made the subject 

 of special discussion by Forster. 



Speck's experiments, 4 which were made after the ingestion of food 

 and with the child in the sitting or standing position, are also un- 

 suitable for comparison with our data. 



The results of Sonden and Tigerstedt's extensive series 5 for the most 

 part can not be employed here, with the exception of the data obtained 

 with two subjects asleep. Thus with one boy, 11 years 2 months old, 

 and with a body-weight of 32 kg., the total heat was 1,237 calories 

 per 24 hours, a value quite in conformity with some points noted by us. 

 Another boy, 12 years of age, showed a somewhat higher heat output 

 of 1,373 calories. 



1 Andral and Gavarret, Ann. d. Chim. et d. Phys., 1843, s6r. 3, 8, p. 129. 



2 Scharling, Ann. d. Chem. u. Pharm., 1843, 45, p. 214; reprinted in detail in Ann. d. Chim. et 



d. Phys., 1843, ser. 3, 8, p. 478. 

 8 Forster, Amtl. Ber. d. 50 Versamml. deutsch. Naturf. u. Aerate in Milnchen, 1877, p. 355; 



also v. Ziemssen's Handbuch der Hygiene, Leipsic, 1882, 1, p. 76. See, also, Magnus-Levy 



and Falk, Archiv f. Anat. u. Physiol., 1899, Suppbd., p. 356. 

 4 Speck, Physiologic des menschlichen Athmens, Leipsic, 1892, p. 217. 

 * Sonden and Tigerstedt, Skand. Archiv f. Physiol., 1895, 6, p. 1. 



