292 APPENDIX. 



ble difference in the length of the column at different 

 times. In young persons the elasticity is much greater 

 than in the aged, these parts gradually hardening with 

 the years a person lives, until the spine finally loses a 

 great proportion of its flexibility, and in these circum- 

 stances, there is very little diurnal difference in the length 

 of the column. But in youthful persons the difference in 

 the length, especially if they are tall, between morning 

 and evening, may be from half to a quarter of an inch, 

 and may be found by the common mode of measuring. 

 Thus do we grow taller during the night, and shorter 

 during the day. 



936. Now these cartilages, being thus compressible 

 and elastic, in young persons, but gradually hardening 

 with age, it is plain that if one edge or side, in such a 

 one be pressed more than the other, and this pressure be 

 continued for any considerable length of time, they will 

 not grow of a uniform thickness, the part thus pressed 

 becoming thinner, and the opposite part thicker than nat- 

 ural. Without reference to growth, the same effect 

 would be produced by the pressure of, and the gradual 

 hardening of these parts. Therefore, if the spinal col- 

 umn be bent into any unnatural shape, and the same pos- 

 ture be continued day after day, and month after month, 

 as is too often the case with young ladies at school, the 

 cartilaginous plates will finally become wedge-shaped, 

 having a thick and a thin edge, and as they harden with 

 age, they will continue to operate as wedges in retain- 

 ing the spine in that crooked state by which they were 

 forced into this form ; and thus the person will probably 

 become deformed for the remainder of her life, in spite 

 of all the frames, pulleys, and weights, and other Pro- 

 crustean apparatus, which may be applied to remedy the 

 evil. 



937. This effect would be produced in such persons as 

 had not arrived at the age when the cartilages become 

 hard. But in those who are quite young, as from in- 

 fancy to twelve or fourteen years, even the bones of the 

 spinal column being still comparatively soft, would con- 

 form more or less to the curvature given it, thus making 

 a deformity from which there is not the slightest hope of 



