104 THE HUMAN LUNGS. 



cle of the frame may take the lead in initiating the action, for all 

 the muscles are connected together, and tend instinctively to influ- 

 ence each other. Thus we may have splenic breathing, or umbilical 

 breathing, or hepatic breathing, according to the part of the surface 

 which begins the inspiratory traction. Now, the spirit of any ac- 

 tion is according to its beginning in the body. But this is too im- 

 portant a subject to be discussed within our present limits. 



It is now, therefore, evident that the movements of the respira- 

 tion are not confined to the chest, but are systemic motions pervad- 

 ing the head, body and limbs, and lying at the basis of the func- 

 tions of the parts; and thus that bodily actions or functions are 

 never created, but only shaped or formed out of a stock of motion 

 given in the nature of things. Furthermore, as habits are no 

 sooner engendered than they are written upon the body, and espe- 

 cially upon the nervous system, it is plain that this habit of recipro- 

 cal breathing is deeply inscribed as a second nature upon the animal 

 textures, and that they tend to fall into it upon the least impulse 

 given ; according to the well-known laws of recurrence in the bodily 

 frame. Thus, on the showing of facts, life may be defined as the 

 progressive education of the organs and viscera into habits of breath- 

 ing which contradistinguish them from dead organs. 



What we have said might have been taken by analogy from the 

 air as well as from the lungs. For the air also has the three func- 

 tions; a chemical, by which it combines with other substances; a 

 statical, by which it presses with so many pounds to the square 

 inch; and a mechanical, by which it serves as a motor force when- 

 ever its columns are displaced or its volume agitated. The lungs, 

 as we have now shown, correspond to, and make use of the air in all 

 these three departments. We may, therefore, resume in saying, 

 that the chemical powers of air are chemico-vital powers of lungs, 

 and the mechanical powers of air, mechanico-vital powers of lungs. 



We do not forget, in these observations, that breathing commences 

 only at birth, and that another order of things prevails previously. 

 But this different state does not contradict the views put forth. 

 Were this the place, we might pursue the thread of science into that 

 other and attractive but mysterious sphere of whose still spring the 

 round of this life jg but the first expansion. But we must be con- 



