SITTING. 293 



, since the great beam of the whole fabric has thus 

 become permanently misshapen. 



938. Sitting Postures described. It might perhaps be 

 considered unnecessary to give any instructions on the 

 most comfortable manner of sitting, it being a natural 

 supposition that every one would consult their own ex- 

 perience in this respect. And yet, it may be the case, 

 that a few observations and experiments on this subject, 

 will be the means of diminishing the pain of those who 

 are for any considerable time confined to this posit on, 

 and thus avoid some of the evils which might otherwise 

 arise from it. 



939. The sitting posture, it will be found, soon be- 

 comes painful, and is maintained with difficulty, when the 

 inferior portion of the spinal column is bent inward, and 

 the arms are thrown back, with an erect position of the 

 neck and head. Even when the spine is supported by a 

 back, as in a chair, this posture becomes uneasy, because 

 the dorsal muscles, and those of respiration also, are kept 

 in an unnecessary state of action. This position will be 

 understood by Fig. 131. 



Fig. 131. Fig. 132. 



940. The most comfortable posture in sitting, is that 

 which at once relaxes the muscles of the back and those 

 of respiration, the inferior portion of the spine being gently 

 curved, but not made crooked ; while the upper part is 

 nearly straight, with the neck a little inclined, so as to 

 25* 



