SYMMETRICAL DEVELOPMENT. 19 



well with either hand. From a physiological point of view, 

 the use of a typewriter is to be preferred, in that it obeys the 

 law of muscle action in allowing periods of rest between 

 periods of action ; whereas, in holding a pen we use one side 

 of the body much more than the other, and keep certain 

 muscles in action nearly all the time. 



There are many advantages in being able to use either 

 hand. The teacher may need to stand on the right side of a 

 blackboard, and therefore to use his left hand. A ball-player 

 loses time if he can throw with only one hand. In carving, in 

 shaving, in bandaging, in administering medicine, it may be 

 necessary to use the left hand skillfully. The pianist and 

 the harpist use the two hands about equally, while the vio- 

 linist puts much more skill into his left hand. Trainers of 

 athletes usually begin by developing the left side of the body 

 till it equals the right in size and strength. 



Our strength depends on our muscles. It is a fine thing 

 to have strong, well-developed muscles, not only because they 

 give beauty of form, but because extra strength and endurance 

 may be needed in case of accident, to save one's own life or 

 that of others. In a case of fire, the ability to climb, to go 

 up or down a rope " hand over hand," may be all-important. 

 Any one's life may depend on his ability to run far and swiftly, 

 to swim, to jump, to lift a heavy weight. 



When we look at the skinned carcass of an animal in the 

 market, we observe that the muscles almost completely cover 

 the bones. The muscles are attached to the bones, and act 

 upon them as levers, giving our motions strength, quickness, 

 and precision. Without bones our motions would be like 

 those of an earthworm or slug, slow and uncertain. The 

 muscles, acting through the bones, can lift a weight that 

 would crush the muscles if laid directly upon them ; while a 

 bone, able to support a heavy weight without being crushed, 



