22 



GASEOUS METABOLISM OF INFANTS. 



production of atrophic infants can be abnormally high aside from 

 any effect which the environmental temperature or the body activity 

 may have upon it. 



Finally the direct calorimetric and gasometric researches of Howland 1 

 in Lusk's laboratory should be especially noted. In discussing the 

 calculation of the body-surface, Howland cites the use of the factor 

 12.3 as a constant for infants, but we are not aware of any writers who 

 have previously used this factor. The experiments were made with the 

 respiration calorimeter 2 at the Cornell University Medical College in New 

 York. Three infants under one year of age were studied and ocular 

 observations of the activity of the infants were recorded. 



Howland's experiments were subsequently published in detail and 

 the results more fully discussed. 3 In this paper the relationship between 

 body-surface and body-weight is extensively treated and the various 

 factors and formulas are considered. A curve is proposed which is 

 represented by the algebraic expression y = mx + b, in which y is the 

 surface area of the infant, x the weight of the infant in grams, m the 

 constant 0.483, and b 730 sq. cm. 



Table 1 1 .—Heat-production of infants, directly and indirectly measured, as reported by Howland. 



The last portion of the paper, which is of most significance, compares 

 the direct and indirect computation of the heat-production of the 

 infants observed. This comparison is of such value to workers in 

 metabolism that it is given here in table 11. The agreement between 

 the heat-production as directly measured and as indirectly computed 

 is striking, to say the least, and justifies for the present the utilization 

 of the indirect method of computing the calorimetry of infants. 



Rowland, Proc. Soc. Exp. Biol, and Med., 1911, 8, p. 63; Hoppe-Seyler's Zeitschr. f. Physiol. 

 Chem. 1911, 74, p. 1. 



*Williams, Jour. Biol. Chem., 1912, 12, p. 317. 



8 Howland, Trans. 15th Int. Congress on Hygiene and Demography, Washington, 1913, 2, 

 p. 438. 



