108 



PHYSIOLOGY 



CHAP. 



centre of gravity is placed lower than in man ; in children, on the 

 contrary, it is higher, owing to the relatively greater or less 

 development of the pelvis. 



In order to ascertain the centre of gravity in the antero- 

 posterior plane of the body, Meyer placed a naked subject in the 

 erect and rigid posture, and then made him bend forward on the 

 front of his feet and his heels as far as possible without falling. 

 By means of a plumb line he determined the lines of gravity in 

 the two most extreme postures, and the points of intersection of 



FIG. 68. Normal position. (Braune and 

 Fischer.) In this position the centres of 

 rotation of the principal articulations fall 

 in the same vertical plane indicated by the 

 line. 



FIG. 69. Military position or "stand at 

 ease." (Braune and Fischer.) In this 

 position the centres of rotation for the 

 lower limbs lie behind the vertical line that 

 passes through the centre of gravity. 



these lines in the body represent its centre of gravity in the given 

 erect and rigid posture. 



More recently Braune and Fischer have applied the same 

 method to the dead body frozen and extended on its back upon a 

 board. The rigid and invariable form of the body enabled them 

 to determine exactly the point of intersection of three perpen- 

 dicular lines of gravity obtained by successively suspending the 

 body in three different positions. 



According to Weber the centre of gravity of the whole body 

 in the erect position is at about the level of the sacral promontory ; 

 according to Meyer it lies at about the upper border of the second 

 sacral vertebra inside the spinal canal ; according to Braune and 

 Fischer it is considerably farther forward, at the level of the upper 

 border of the third sacral vertebra. 



