THE HUMAN FRAME. S*!? 



must be considerably less. The statue of an elephant, placed 

 upon a level surface, would stand without danger of overset- 

 ting: but the statue of a man, resting on the feet, in the usual 

 attitude of standing, Avould he thrown down by a very small 

 impulse. It is evident, indeed, that in the living body, if 

 the centre of gravity were at any moment to pass beyond 

 the base, no muscular effort which could then be made, would 

 avail, to prevent the body from falling. But the actions of 

 the muscles are continually exerted to prevent the yielding 

 of the joints under the weiglit of the body, which tends to 

 bend them. In quadrupeds, less exertion is requisite for 

 that purpose; and standing is in them, as we have seen, a 

 posture of comparative repose: in man it requires nearly as 

 great an expenditure of muscular power as the act of walk- 

 ing. Soldiers, on parade, experience more fatigue by re- 

 maining in the attitude of standing, than they would by 

 marching, during an equal time. Strictly speaking, indeed, 

 it is impossible for even the strongest man to remain on his 

 legs, in precisely the same position, for any considerable 

 length of time. The muscles in action soon become fatigued, 

 and require to be relieved by varying the points of support, 

 so as to bring other muscles into play. Hence, the weight 

 of the body is transferred altcrnatel}' from one foot to the 

 other. The action of standing consists, in fact, of a series of 

 small and imperceptible motions, by which the centre of 

 gravity is perpetually shifted from one part of the base to 

 another; the tendency to fall to any one side being quickly 

 counteracted by an insensible movement in a contrary direc- 

 tion. Long habit has rendered us unconscious of these ex- 

 ertions, which we are, nevertheless, continually making; 

 but a child learning to walk finds it difficult to accomplish 

 them successfully. It is one among those arts which he has 

 to acquire, and which costs him, in the apprenticeship, many 

 painful efforts, and many discouraging falls. But whenever 

 nature is the teacher, the scholar makes rapid progress in 

 learning; and no sooner have the muscles acquired tJie ne- 

 cessary strength, than the child becomes an adept in ba- 



