114 PHYSIOLOGY. 



Living Principle, its union with Body. 



The Living Principle is not simply diffused, but it is combined, or 

 makes one of the constituent parts of the whole, and the variety of 

 actions arises from the construction of the parts. I should call theharmony 

 between one part of the body and another ' vital harmony ; ' as, for 

 instance, the harmony of the blood with itself; the blood with the 

 vessels ; one part of the body with another, where the connexion is only 

 contact, which parts can be shifted without injury owing to this 

 harmony. 



Living Principle, its Nature and Degrees. 



A young animal has the Living Principle more lively, but perhaps 

 not so strong, as an old one. Injuries that do not affect the whole, are 

 sooner repaired : a broken bone unites sooner ; a cut unites or heals 

 sooner. But the whole living principle is sooner destroyed : young 

 animals cannot endure hunger and cold so long : pain throws them into 

 convulsions, so as to destroy life itself. 



Whatever Life is, it most certainly does not depend upon structure or 

 organization 1 . In contradiction to organization being a cause, we find 

 in general that the least organized are the most tenacious of life. Thus we 

 find that, in general, the most imperfect animals are the most difficult 

 to be killed, when the actions of the parts are stopped upon which life 

 is continued. But this is not constantly so, therefore peculiarity of 

 organization is not in the least necessary. 



A still stronger proof than the one above, that organization is not 

 essential to Life, viz. that different organizations make no difference 

 [in respect to life in the abstract], is, that different animals with the 

 same organization are very different with respect to their being easy or 

 difficult to be killed by the stoppage of those operations that continue 

 life. For instance, an eel will live out of water for many days, while a 

 mackerel dies instantaneously : a carp will live many weeks out of water 

 if kept in a moist place. These differences only respect respiration ; 

 which, however, is essential to life, although not so much so in some 

 animals as in others. 



A very great difference will take place in the same organization with 

 respect to food ; a sparrow, a linnet, &c, will soon die, if not regularly 

 supplied with food ; while an eagle, hawk, swallow, &c, will five a 

 great while without a supply. The food indeed is different, but the 



1 [I leave these passages without comment : they may serve to throw light on the 

 ofteu mooted question of Hunter's real opinions on the subject.] 



