THE LEVERS OF THE BODY 



57 



Levers of the second order : 



(i) Illustrated by lifting one leg off the ground. In this case 

 the hip-joint is the fulcrum, the leg is the weight to be moved, and 



Fig. 68. The Motion of the Body on 

 the Hip. 



Fig. 69. Lifting the Leg. 



the lifting power is produced by the contraction of a muscle which 

 extends from the hip-bone to the knee-cap. (Fig. 69). 



Fig. 70. Raising the Body on the Toe. 



(2) Raising the body on the toe. The toe rests on the ground, 

 thus forming the fulcrum. The weight is that of the body sup- 

 ported at the ankle, and the power is supplied by the contraction 

 of the muscles of the calf, which are connected with the heel. 



