THE SKELETON.' 15 



The lower leg has two bones the tibia 

 and Foot!* ( a )> and the^ftwZa (b). The knee-joint, 

 between the thigh bone and the bones of 

 the lower leg, is protected by a flat bone called the 

 knee-pan (2). There are seven bones in each heel, 

 five in the middle part of each foot, three in each of 

 the larger toes, and two in each great toe. 



Notice this peculiarity in the form of the foot. It 

 is curved or arched from the heel to the front. 

 Here is another arrangement for springiness, with- 

 out which, walking would not only become clumsy 

 but painful. 



The bones of a grown person are so much 

 hardened by the mineral matter which 

 has increased in their structure, that they 

 are not easily changed in shape. They are more 

 easily broken than bent. Neither is the full-grown 

 joint likely to change in shape and character during 

 the active years of life. So the general carriage of 

 the body in adult life, depends on the habits and 

 circumstances which shaped it in youth. We have 

 learned that in childhood the bones are quite flexible 

 and disposed to bend, instead of breaking, under a 

 strain. For this reason, children who begin to walk 

 very early become more or less bow-legged. Pupils 

 who are in the habit of leaning forward on the desk, 

 in school, will certainly, more or less deform their 

 bodies. If a boy, in walking, carries his body in a 

 lazy, stoop-shouldered position, he will go bent and 

 deformed through life. Avoid leaning the body 



