340 



THE HUMAN MOTOR 



We can observe on every side applications of this principle 

 of equilibrium. Thus the 

 cyclist (fig. 240) bends over 

 his base of support. The 

 boxer, the fencer, the 

 soldier, with pack and rifle, 

 are ruled by the same prin- 

 ciple. In such cases the 

 equilibrium is more or less 

 constrained, and the static 

 expenditure of energy is 

 correspondingly greater 

 than in the state of rest. 



For example, the soldier 

 standing at " attention " 

 with his rifle on his shoulder 

 and his pack on his back, 



is far from being in a state Equilibrium of a cyclist, 



of rest. The attitude is really most uneconomical. An excess 

 in the opposite direction is exhibited in an asymmetrical attitude, 

 in which the abdomen is allowed to project in front of the chest. 

 This attitude is moderatelv economical, though less so than the 

 haunched attitude (fig. 235). 



262. Summary. The results obtained by the experiments 

 of Braune and Fischer give a location for the centre of gravity 

 of the whole body, at about j% 7 n of the height. That of the bust 

 alone lies approximately 18 cm. above the transverse axis of the 

 hips. The bust is 63% and the lower members 37% of the total 

 weight of the body. For an adult weighing 65 kg. the bust 

 weighs 41 kg. and the lower members 24 kg. The weight of the 

 lower leg is 6-83% of the total weight of the body. The total 

 length of the lower member of an adult varies from -87 to '9 

 metres or on the average -88 metres. Its total weight is 12 kg., 

 of which the lower leg claims 4-4 kg. 



These measurements and dimensions will be found of consider- 

 able use later. It may be remarked that they differ but slightly 

 from the average results obtained by Otto Fischer, f 1 ) The ex- 

 periments of Atwater (vide 103) show that for an adult placed 

 in a chamber at a temperature of 20 C., the expenditure of energy 



2120 

 is 2,120 Calories, i.e., ^j-^- A = 1-36 Calories per kilogram of 



DO X ^4 



body weight, per hour. In open-air life, as will be seen later 

 ( 341), this figure may reach 1-5 Calories, this being due to the 

 lower temperature (14 to 15 C.) and to the general state of 



( l ) Otto Fischer, Der Gang des Menschen (vol. xxv., No. 1, p. 16, of the 

 Abhandl d. Math. Phys Classe d. Sachs. Gesellsch. d. Wiss., Leipzig, 1899). 



