198 



relation subsisting between these and others belonging to a diffe- 

 rent seat, suggest, on the ground of analogy, that the existence of a 

 similar dependence should be investigated in this instance. It is to 

 be asked, 



1st, Is the spirit, which by its relation with venous blood forms 

 bile, the regular assimilating life of the structure? or, 



2nd, Is it dependent upon the vital properties of another seat? 

 and, if dependent, 



3rd, Is the dependence regular? or is the communication constant, 

 by the force of a natural relation? or is it of the occasional kind? 

 19. In this case also, in inquiring into a dependence, it is our 

 first suggestion from analogy to intercept the communication of the 

 hepatic nerves with their centres. This should be done so near to 

 their entrance into the liver as to obviate any confusion which might 

 arise from considering the communication with their ganglia as 

 equivalent to a connexion with the brain or spinal marrow. The 

 result of this experiment would be, either that the secretion of bile 

 proceeded as usual, or that it was suspended. If the former, the 

 independence of the functional spirit of the liver of properties exist- 

 ing in the seats of the nervous centres would be shewn; if the latter, 

 viz. that the secretion of bile was suspended, then it would be in- 

 ferred that the functional life of the liver acknowledged a dependence 

 upon a distant seat. This inference would be sanctioned by certain 

 analogies, proving that where there is no dependence the injury in- 

 flicted by simple division does not tend to suspend or impair organic 

 processes. The dependence in this case, as before suggested, would 

 be one of two kinds, either for the receipt or the privation of certain 

 properties, by the force of a distant relation ; which of these remains 

 to be discriminated, for which purpose we are not without some 

 analogies. 



20. With respect to the third question, viz. whether, -the de- 

 pendence being proved, it is of the regular or occasional kind, this 

 is to be determined only by observing the conformity of the result 

 of the function with these alternatives respectively. It will be 

 asserted that the secretion of bile is unremitting, and that therefore 

 the communication which makes the dependence, if any, must be so 

 too. That bile is unremittingly secreted is probable, and if it is not, 

 I do not perceive to what occasional cause an irregular communica- 

 tion can be ascribed in this instance. If a summary of the function 

 of the liver were to be attempted upon an imperfect evidence on 

 many points, furnished by loose and distant analogies, it would be 

 of the following kind. 



'21. Bile is produced by the secerning structure of the liver. 

 It is produced by a relation which subsists betxveen the functional 

 life of this structure and venous blood. The functional life of the 

 liver is of the regular dependent kind : that is, the assimilating life 

 of the structure is so related with arterial blood as to produce itself, 

 or to separate and unite its elements; properties communicated 

 from another seat unite with the assimilating life of .the secerning 



