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A TEXTBOOK OF PHYSIOLOGY 



This is seen in the following table from experiments on animals 

 during a period of twenty -four hours' hunger: 



This rule holds for larger and smaller animals of the same 

 species, as may be seen from the following figure. 



The accompanying table shows the oxygen use per minuta in man 

 in the first few years of life, and again at the age of puberty. 



Years. 



Weight 

 in Kilos. 



% consumed (). ? Use per 

 per Min., Kilo of 



C.C. 



Relative Consumption 

 of Oxygen to A dull 

 (Standard^ 100). 



The basal metabolism of man, measured under conditions of fast- 

 ing and rest in bed, is 40 calories per hour per sq. metre of skin sur- 

 face, 37 for woman, 50 for boys of 12-13 years. The formula used for 

 measuring the surface is A W ' 425 x H ' 725 x 71-84. A = sq. metres; 

 W = weight in kilogrammes; H = height in centimetres. 



In young animals the increased metabolism may be due in part to 

 the actual processes of metabolism being more active in the growing 

 than in the adult animal. During the early months of their life infants 

 appear to be an exception to the rule ; their metabolism is much lower 

 than it should be as calculated from the body surface. The infant is 

 kept warm, and sleeps quietly most of its time in cradle or pram. 

 This very likely is not the case with the infant of the native Austra- 

 lim or Terra del Fuegian. Infants are generally over-coddled, and 

 are made more virile by some exposure to cold and exercise. In old 

 age the metabolism is reduced. 



It is doubtful whether sex influences the metabolism in any degree. 



