286 



APPENDIX. 



parts of the body above the hips, down through the 

 lower limbs to the feet ; and hence the necessity that 

 this column should have great strength and firmness, as 

 formerly shown. 



915. In standing, if the spine is bent backward so as 

 to throw the line of the centre of gravity behind the base, 

 the position soon becomes painful ; since the muscles of 

 the back must be in a continued state of unnatural ten- 

 sion, in order to maintain this position, and also because 

 the muscles of the lower limbs are unduly straightened, 

 for the purpose of preventing the body from declining 

 backward, and thus losing its balance. This uncomfort- 

 able position is represented by Fig. 128. 



916. The most natural posture in standing, is that which 



Fig. 128. Fig. 129. 



can be supported longest with the least fatigue, and this 

 appears to be when the spinal column is kept in a posi- 

 tion similar to that shown by Fig. 63 ; the muscles of 

 the back being kepi: in only just sufficient action to main- 

 tain the spine erect; the chest and arms, at the same 

 time, being thrown forward, so as to bring the centre of 

 gravity somewhat forward, rather than behind the base, 

 as shown by Fig. 129. In this posture, all the muscles 

 will be found to be in as complete a state of relaxation, 

 as is consistent with the erect position of the body. 



917. If the pupil will imitate a few times the different 

 postures here represented, she will soon find by expe- 

 rience, that one can be maintained much longer than the 

 other 



