STANDING. 279 



The Foot. In describing the parts concerned in stand- 

 ing and walking, we will begin with the base, or foun- 

 dation. 



We will however only give a slight description of the 

 bones of this part. The tarsus is that part which reach- 

 es from the heel to the middle of the foot, marked a, fig. 

 130. It is composed of seven bones. The metatarsus, 

 6, consists of five long bones, laid close together, and 

 reaching from the tarsus to the roots of the toes. The 

 phalanges, c, or bones of the toes, are so called because 

 each row forms a phalanx. Of these there are fourteen 

 in the whole. Thus the bones of the foot are 26 in 

 number. These are covered with cartilages, and sup- 

 plied with tendons ; the first binding them together in 

 the strongest manner, and the second giving them mo- 

 tion in all directions. There is indeed no part of the 

 human frame which is put together with so much care, 

 and so strongly guarded against accidents, as the foot. 

 It is obvious that were this not the case, so small a part 

 would not withstand the violent concussions to which it 

 is subjected, in sustaining the whole weight of the body, 

 in leaping and other exercises. 



The two bones of the lower limb, the tibia, or shin 

 bone, and fibula, which is placed on its outside, form by 

 their lower extremities, the inner and outer ankle bones. 

 These are articulated with the great bone of the foot, 

 called the astragalus ; by which a hinge joint is formed, 

 having also some lateral motion. 



Now when we walk, this joint allows the foot to roll 

 easily upon the ends of these bones, so that the toes may 

 be directed according to the inequalities of the surface 

 over which we pass. But when the foot is fixed on the 

 ground, the muscles instantly act in such a manner as to 

 give the joint a firm support, so that the whole body rests 

 upon it, while the other foot is carried forward. 



In walking, the heel first touches the ground, at "which 

 instant the bones of the leg and foot are in the positions 

 with respect to each other, represented by Fig. 130. If 

 the legs were situated perpendicularly over the part 

 which first comes to the ground, we should come down 

 with a dead blow, or jolt, as one does who has a wood- 



