THE LAWS OF ORGANIC 



situation and form ; the atmospheric air rushes 

 in to dilate the cells, which had previously been 

 compressed, or almost obliterated ; and the blood 

 likewise, jinding less resistance in the chest, flows 

 towards it in greater quantity than usual producing 

 palpitation of the heart, if the quantity be slight ; 

 if inordinate, syncope, from the great oppression. 



CCCLXX. The alterations which the ab- 

 domen undergoes in parturition may be re- 

 garded as operating in the same manner upon 

 the chest and its contents, and we have some- 

 times the same effects ; but Nature, by certain 

 wise provisions, has diminished very much the 

 liability of the female to such occurrences. The 

 first five or six months of gestation are attended 

 by a greater difficulty of breathing and thoracic 

 derangements than the remainder of the period ; 

 and this arises from the situation of the foetus, 

 which is principally confined to the upper part 

 of the abdomen, and therefore more injurious to 

 the respiratory function ; but, from this time to 

 the period of confinement, it gradually descends, 

 and occupies the lower region of the abdominal 

 cavity, relieving the function of respiration. 

 During the pains of parturition the foetus de- 

 scends still more, till at last it reaches the pelvis. 

 The gradual changes during labour having the 

 tendency to effect this end, the sudden expulsion 

 of the fcetus is not accompanied by serious 

 results ; because the respiratory organs have, by 



