AND THE LIVING PRINCIPLE. 



267 



may be supposed to augment the secretions, and, 

 consequently, the depositations. 



These are simple views, and draw hut little on the 

 imagination for their support. There is, however, a 

 greater difficulty remaining ; not as to the existence 

 of a thinking or discriminating power, but as to a 

 living principle, distinct from sentient existence, and 

 from mere mechanical and chemical agency. We 

 can comprehend how the chyle and the blood may, 

 in their progress from stage to stage, supply all the 

 varied demand of membrane, muscle and bone ; but 

 it remains unexplained, by any of the principles 

 with which we are familiar, in what way are gene- 

 rated or continued, those motions which carry the 

 nourishment to these different stages, and expel 

 what is either superfluous or unfit for use. The pe- 

 ristaltic motion, the pulsation of the heart, and the 

 involuntary movements of the muscles, exhibit phe- 

 nomena inconsistent with the idea of inert matter, 

 and equally distant from the effects of attraction or 

 repulsion. These motions may all, indeed, be refer- 

 red to muscular motion ; and it seems also to be 

 true, that all muscular motion depends on nervous 

 energy or irritability ; but this only leads us to a 

 more wonderful contemplation. The whole animal 

 frame is ramified with nerves ; and their universal 

 efficiency is proved, by the immediate destruction of 

 those parts, the nervous fabric of which is destroyed. 

 How the nerves communicate information we do 

 not know ; but in whatever way effected, the change 



