540 



METABOLISM 



Surface in square cm. 



(1) 10,750 



(2) 7,662 



(3) 5,286 



(4) 3,724 



(5) 2,423 



Heat production in calorics 

 per square meter of sur- 

 face per day 

 1036 

 1097 

 1183 

 1153 

 1212 



(Rubner) 



Such results have prompted observers to conclude that the determining 

 factor in the calorie output of warm-blooded animals is the relative sur- 

 face of the animal. This is greater the smaller the animal, with the con- 

 sequence that heat is more rapidly lost to the surrounding air from the 

 surface, thus requiring more active combustion. Until quite recently it has 

 been generally believed that such a relationship between body surface and 

 heat production did actually exist, but, thanks to the work of F. G. Bene- 

 dict 7 and E. F. and D. Du Bois 6 , it is now known that the calculations were 



WEIGHT-KILOGRAMS 



Fig. 175. Chart for determining surface area of man in square meters from weight in kilo- 

 grams (Wt.) and height in centimeters (Ht.) according to the formula: Area (Sq. Cm.) = Wt. 

 0.425 XHt. 0.725 X71.84. (From Dubois and Dubois, Arch. Int. Med., 1917, vol. 17.) 



based upon incorrect computations of the body surface. In the older re- 

 searches the calculation was made by using a formula known as Meeh's, in 

 which weight was multiplied by a certain factor (viz., 12.312 x ^weight). 

 Du Bois, however, has shown that an average error of 16 per cent is in- 

 curred in using this formula. For accurate measurement the body was 

 covered with thin underwear, which was then impregnated with melted 

 paraffin and reinforced with paper strips to prevent it from changing in 

 area when removed. This model of the surface was afterwards cut up 

 into flat pieces and photographed on paper of uniform thickness, the pat- 



