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5. Hence the alternatives to be decided upon in this stage of 

 the inquiry arc, whether the entrance of fluids from the intestines 

 into the mesenteric absorbents is a process wholly hydraulic or 

 wholly functional, or whether not exclusively either, but of the 

 mixed kind? These alternatives may be discussed by consulting 

 analogies, &c. to some length ; but as we do not possess the facts 

 which will justify any very positive conclusion, I shall leave them as 

 alternatives on which our decision is suspended. 



6. Although we cannot determine whether the hydraulic pro- 

 cesses have any, or how great, a share in the entrance of fluids into 

 the lacteals, it will scarcely be doubted that the orifices of these 

 vessels operate processes upon the intestinal material of the functional 

 kind. We know that the fluids of the intestines are mixed, and that 

 it is inconsistent with analogy (as well, perhaps, as verifiable by 

 direct experiment) that the separation of lacteal fluid from this mass 

 should be performed by a mere mechanical filtration, or a mere 

 capillary absorption. If then the separation is an animal process, 

 in some respects resembling secretion, it is to be investigated rather 

 according to the laws of life than of inanimate matter. 



7. Does any lacteal absorption go on after death? An animal 

 may be killed a few hours after a full meal, at a time when it might 

 be presumed the nutrient fluids exist copiously in the bowels : it is 

 possible that, under these circumstances, by examining with a magni- 

 fier one or more lacteal trunks, the contents of which are compressed 

 out, it may be ascertained, either by their filling again or remaining 

 empty, whether lacteal chyle is separated and absorbed from among 

 the general contents of the intestines after life is extinct. The 

 peristaltic movements may be imitated, or the contents of the small 

 intestines agitated, with a view to facilitate mechanical separations; 

 and under the experiment the animal temperature may also be pre- 

 served. If no absorption took place, as from analogy seems most 

 probable, it would then be decided that this instance of absorption 

 is wholly an animal process. Presuming that it is an animal process 

 from the analogies hinted at (which may be adverted to in the gross, 

 by saying that none of the processes which take place during life 

 happen in the same way after death), presuming upon these analo- 

 gies, it is to be inquired in what way, or what are the agents mutually 

 concerned in the separation and absorption of chyle from the intes- 

 tines by the operation or concurrence of the properties of life? 



8. It may here be urged against the conclusiveness of the 

 above experiment, that after death the area of the absorbents is 

 different from that which obtained during life; and hence a separa- 

 tion of an hydraulic kind may not take place from an altered diame- 

 ter of the tubes which should perform it. This objection, however, 

 is of no great weight; for we can conceive a fault in the diameter of 

 the tubes to be one of only two kinds, they are either too large or 

 too small. Now it is ascertained in the sanguiferous system, and it 

 is here in consonance with every analogy which can be cited, that 

 the area of vessels is greater during life than after death ; that is, both 



