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departments ; we find that the most powerful agents which affect 

 the spirit are of the chymical kind; we know how life and its pro- 

 cesses are modified by them ; and we see them, as in the cases of 

 poisons, producing its extinction, &c. But although from their 

 alliance we consider these properties as chymical, yet may they (the 

 efficient ones) be wholly vital, and not those by which the pheno- 

 mena of the laboratory are accomplished. My meaning may be 

 illustrated by a supposed example. Thus, death may be occasioned 

 by one of the metallic oxyds: with respect to its chyraical nature, it 

 is an oxygenated metal which kills ; but it may possess properties 

 related with life, which do not belong to the metal or to the oxygen, 

 but which are allied or associated with them, and having their rela- 

 tion only with vital properties, are inefficient in regard to the 

 chymical ones: that is, the chymical substances may be related with 

 those of their own kind, which are met with in the laboratory; and 

 their vital associated properties also with those of their own kind, 

 which are met with in living bodies, and perhaps in spontaneous 

 formations approaching to life. This, however, is a refinement 

 merely consistent with the doctrines of causation, and not worthy of 

 attention in the present state of analytical research, which is yet to 

 be employed upon grosser matters. To return from this digression: 

 the supposition of a mechanical agency in this business of lacteal 

 separation and absorption is, on the grounds referred to, dismissed. 

 With regard to the chymical, we observe that the agents of chymis- 

 try are generally of the material kind; hence we have difficulty in 

 distinguishing their share in phenomena occurring by means of the 

 secretions, but not in places where secretions do not take place; and 

 as the absorbent, in some respects stands contra-distinguished to the 

 secerning, extremities, so on this ground the supposition of a chymi- 

 cal agency can scarcely be indulged. According then to this view, 

 at least the principal agency in the business we are considering ap- 

 pears of the spiritual kind. 



4th, Are the separation of lacteal fluid from intestinal chyle and 

 its absorption to be considered as the result of one process, or are 

 they accomplished by the same properties? We can answer this 

 question only by remarking, that the absorbents elsewhere shew a 

 capability of absorbing almost any substances which are fairly sub- 

 mitted to their action ; and that when, as in the present case, they 

 take only, from among many, one fluid, which rarely digresses from 

 a pretty uniform character, the exception must be attributed to some 

 peculiarity, to the operation of properties which do not obtain gene- 

 rally in the absorbent system. Whether these modifying properties^ 

 those which make this example of absorption peculiar, are those 

 upon which also depend the separation of lacteal fluid from the in- 

 testinal material, is more than can be decided, or even conjectured 

 upon with any great shew of truth, in the present state of our 

 evidences. 



5th, Is lacteal fluid a mere separation? or is it a new constitution 

 made up by a combination of properties from absorbent orifices 



