202 A BIOMETRIC STUDY OF BASAL METABOLISM IN MAN. 



as to exclude them for use as indices of basal metabolism. These 

 authors based their comparisons on the carbon-dioxide excretion per 

 hour per kilogram of body- weight and per square meter of body-surface. 

 They express the relationship between the gaseous exchange of men 

 and women as a proportion. Their end results are summarized in 

 table 76. They conclude that in youth the carbon-dioxide production 

 of boys is considerably greater than that of girls of about the same age 

 and body-weight, but with increasing age this difference gradually 

 becomes less and less, and finally in old age it disappears entirely. It 

 must be noted here that the authors specifically state that it appears 

 to them that new experiments are necessary before this problem can 

 be completely solved. 



TABLE 76. Comparison of carbon-dioxide production in men and women: data of Sonden 



and Tigerstedt. 



In 1899 Magnus-Levy and Falk 7 published an extended series of 

 observations on both men and women in which the Zuntz-Geppert 

 respiration apparatus was employed. Although Johannson 8 had 

 shortly before emphasized the importance of controlling muscular 

 repose and had outlined his experience in the voluntary exclusion of 

 muscular activity, these observations of Magnus-Levy and Falk 

 represent the first comparative observations made upon both men and 

 women in which particular attention was given to complete muscular 

 rest; hence they are more nearly comparable with our experiments 

 than any series published previous to 1899. The series with men 

 comprise observations on 16 boys, 10 men between 22 and 56 years 

 of age, and 5 men 64 years old and over. The series of women include 

 observations on 9 girls, 15 women between 17 and 57, and 7 women of 

 71 years or older. The data as to age, weight, and height are recorded. 

 The authors have likewise computed the values per kilogram per 

 minute and per square meter of body-surface per minute. In their 

 comparisons of the values obtained with men and women on the basis 



7 Magnus-Levy and Falk, Arch. f. Anat. u. Physiol., Physiol. Abt., Suppl., 1899, p. 314. 



8 Johannson, Skand. Arch. f. Physiol., 1898, 8, p. 85. 



