408 THE LAWS OF ORGANIC 



ments similar to what take place at the acme of 

 life, if the extensibility and resisting power of 

 the orta and pulmonary artery were the only or 

 chief differences of the two periods. 



There are three reasons which induce me to 

 dissent from Dr Cu ,i EN'S explanation : 



, The comparative unfrequency of hemop- 

 tysis is one of considerable importance. If we 

 suppose, agreeably to him, that certain great 

 organic and functional changes take place at any 

 two or three periods of existence, and that these 

 are not peculiar to one individual, but are com- 

 mon to all mankind, from the operation of uni- 

 versal causes on matter precisely of the same na- 

 ture, is it philosophical to bring forward a few 

 solitary cases in support of principles that are found 

 inefficient in their general application ? 



b, The second objection to this view is, that 

 the aorta and pulmonary artery are sometimes 

 found to be partly ossified without this condition 

 having been characterized by hemoptysis, or 

 any unpleasant symptom. When the parts are 

 thus disorganized, the distending power and ex- 

 tensibility must be materially diminished. 



c, In the third place, HIPPOCRATES has stated, 

 that hemoptysis happens between the age of 

 15 and 35 ; and to this observation Dr CULLEN 

 assents. If hemoptysis depend on any particu- 

 lar conformation of an organ or organs, or on 

 #ny constitutional change that occurs, or is liable 



