THE MUSCLES 49 



of uncomfortable shoes on muscular activity ; mind and disposition. 

 4. State effect of aversion to walking on muscles; circulation. 5. If 

 a shoe is too loose, it slips up and down at the heel and chafes the skin 

 there ; if too tight, there is pres- 

 sure on the toes, which causes a 

 corn or ingrowing nail. Have 

 your shoes been correct, or have 

 they been too loose or too tight? 



According to this test, what pro- . 



FIG. 52. ARCH OF FOOT. It forms an 

 portion of people wear shoes that dastic spring _ 



are too tight? 6. How many 



sprained ankles have you known among boys ; girls ? 7. Why is it 

 that people who grow up in warm climates have high, arched insteps, 

 and short, broad, elastic feet, but people of the same race who pass their 

 childhood in cold climates often have long narrow feet with low arches 

 and sometimes have the deformity called " flat foot " ? 



Instinct as a Guide for using the Muscles. The instinctive feeling 

 called fatigue tells us when to rest. There is also a restless, uneasy 

 feeling that comes over a normal human being when confinement and 

 restraint of the muscles have reached an unhealthy limit. This feeling 

 should not be repressed for long at a time. Many, ruled by avarice, 

 ambition, interest in sedentary work, a silly notion of respectability, or 

 a false conception of duty, have repressed this feeling and have lost 

 it. There is then a feeling of languor, and a disinclination to the very 

 activity which health demands. An unheeded instinct is as useless as 

 an alarm clock that has been habitually disregarded. 



Exercise and Climate. In our warmest states and in the tropics, 

 one hour's vigorous physical labor a day, combined with the ordinary 

 activities of life, will keep a person in good condition. In the colder 

 states, muscular exertion for several hours is needed daily. 



Complete Living. Numberless people have devoted themselves to 

 an intellectual occupation, and planned to keep their bodies sound by 

 gymnastics and special exercises. Because of the monotony of exer- 

 cises, they are soon given up in nearly every instance. The safest way 

 is neater to allow all the energies to be devoted to a one-sided occupation, 

 but so to plan one^s life and work that a part of the time is devoted to 

 some physical work, whether it be in a garden, workshop, or orchard ; 

 in walking a long distance to the office ; at bookbinding, cooking, wood 

 carving, or any one of various other useful occupations. The result of 

 manual training shows that not only strength of body, but strength of 

 mind, is promoted by physical labor. Problems of war and of the chase 

 kept active both the body and mind of the savage. Hence he led 

 E 



