24 PHYSIOLOGY AND TEMPERANCE. 



upon each other in all directions. If we keep the spine bent 

 a long time, these cushions will not readily resume their 

 proper shape, and in this way people become stooped, espe- 

 cially in old age, when the cartilage is less elastic. In a 

 young person it is sufficiently yielding to make nearly an 

 inch difference in the height between rising in the morning 

 and at bedtime, after standing upright all day. 



A side view of the spinal column shows it to be curved. 

 In the neck it bends a little forward. Just below this it is 

 bowed backwards. This increases the capacity of the chest. 

 Then bending forward, it affords an advantageous resting- 

 place for important organs in the abdomen, and gives behind 

 favorable points of attachment to large muscles extending to 

 the legs. The large wedge-shaped part of the spine, filling in 

 the space between the hip bones behind, forms a well-marked 

 curve backward and then forward, and secures a perfect 

 resting-place for the organs contained within. This double 

 curving of the spine tends also to disperse the force of a fall. 

 These gentle curves have besides the effect of giving to the 

 body a pleasing and graceful outline, but if they are much 

 increased it becomes a deformity. In rickets, for example, 

 the bones of the spine are softened. The weight of the body, 

 especially if the child is kept standing a great deal, presses 

 the soft bones closer together in front, and increases the 

 curve at the back. 



The various bones of the spinal column fit so nicely into 

 each other, and are bound together so firmly by strong liga- 

 ments, that fractures and dislocations are very rare. The 

 head moves freely backward and forward as it rocks upon the 

 first bone of the spine. It turns from side to side around 

 a pivot in the second bone, carrying with it the first. We 

 bend the spine in some cases almost double, as may be seen 

 in the performances of an athlete, and yet there is no dis- 

 placement nor injury to the delicate cord within. 



