62 Life and Health 



been invulnerable except at this point. The muscles of 

 the calf of the leg have great power, and are constantly 

 called into use in walking, cycling, dancing, and leaping. 



FIG. 36. A Few of the Important Muscles of the Back. 



90. Effect of Alcoholic Beverages upon Muscular Work. 

 Alcohol, even in small quantities, tends to depress the 

 nervous centers, and thus indirectly relaxes the muscles. 



