180 



concerned, respectively, have in the process we are considering. 

 But the final purpose of their concurrence is sufficiently clear. 



$ 15. The substances which support life, when submitted to the 

 functions of the preparatory organs, not only will not support, but 

 actually destroy it, if introduced into the circulation in their crude 

 state. * Hence it is obvious that the final purpose of the function of 

 the stomach is to produce in food a change which constitutes the 

 second stage (mastication and deglutition comprising the first) of 

 preparation, for such a relation with the other seats of life and 

 organization as will concur towards their support. 



16. The life of the stomach has been divided into the regular 

 assimilating, and the dependent functionary. The former is that 

 properly belonging to the texture, and is independent of all other 

 seats, being dependent only upon the properties of arterial blood : 

 the latter is so far dependent upon another seat, that a division 

 (which we have admitted as a test of influence by privation) of the 

 nerves which supply the stomach will impair, or perhaps incapacitate 

 the organ for its digestive function. 



17. The laws which govern the functionary life are perhaps in 

 many circumstances irregular. In the instances quoted from the 

 animal system, we have observed that the influence communicated 

 to a distant seat is traceable to a foreign cause, which disturbs the 

 natural state of quiescence, and in some measure of independence. 

 Thus the muscles of the legs may act in consequence of an operation 

 upon the auditory or optic nerves, &c. In other words, an influ- 

 ence is communicated to the brain, of the occasional sort, which if 

 the muscles of the legs before possessed, independently of the 

 brain, they would move, whether a train of actions were laid or not, 

 by an operation upon the auditory or optic nerves. 



18. But, although communication of influence making function 

 is clearly shewn to take place in many instances, as the result of a 

 relation which is manifested under preternatural circumstances; as 

 in the examples just quoted, by foreign excitation; yet it does not 

 foljow but communications for the same end, viz. that of perfecting 

 functions, may be perpetually taking place under the operations of 

 causes, which are so far natural, that they may even be possessed 

 by the foetus. Such a perpetual communication may take place 

 without invalidating our distinction of the assimilating and de- 

 pendent or occasional life; and whether the communication does 

 take place in the subject of our present consideration, we are to 

 examine. The question relates to the organic system. 



19. The proper secretion of the stomach is formed when this 

 organ is under no foreign excitement by food, or, in other words, 

 when it is empty. If the properties necessary to the secretion do 

 not wholly belong to the stomach, but are in part derived from 

 another seat, then this example furnishes a proof of a spontaneous 

 diffusion of vital properties, and an alliance of them with the in- 

 herent life of the seat to which they are conveyed, for the purpose 

 of establishing a function. It bag been assumed, upon tbe credit of 



