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the disorder ceases; the relation of the emetic is with certain pro- 

 perties belonging to the structures, which, in conjunction with it, 

 produce the state necessary to the act of vomiting; by this action 

 the bile is ejected. Disorder, dependent upon the presence of in- 

 durated faeces in the colon, is cured by purgatives; the relation of 

 the purgatives is with the secerning function of the internal coat of 

 the intestines, perhaps also with the mesenteric absorbents, and with 

 the properties concerned in the peristaltic motions of the intestines. 

 The indurated faeces are removed from the colon, as a consequence 

 of the state produced by this mediate relation. 



3. The remedies belonging to the third class are the most 

 numerous, and it is upon these that we rely (and the grounds of 

 this reliance will come to be examined) in all cases in which the 

 efficient cause is not known. To exemplify this class of medicines 

 which cure by latent causation: a disorder of the head may be cured 

 by repeated bleedings, local or general; long before the period at 

 which the disorder ceases, there may be much less blood than is 

 compatible with perfect health; that is, the disease continues when 

 the quantity of blood in the system is considerably less than at a 

 former period of health; bleeding then in this case does not cure by 

 removing a sensible cause of disease. A fever may be cured by 

 bleedings, purgatives, antimony, &c.: we do not know the cause of 

 fever, or if we can assign any cause it may be a remote one, which 

 has ceased to operate, such as cold; the phenomena of fever are 

 produced by a modified state of the principle of life; who can say 

 in what this modification consists? or, what cause (supposing the 

 state to be produced by some foreign properties) is removed by the 

 remedies? or, supposing the state to consist of deficient causes, 

 what properties, or whether any existing in the remedies, are the 

 identical ones which the spirit requires in order to have its state of 

 health restored? An berpetic eruption on the skin may be cured by 

 arsenic : who can specify the causation among the properties engaged 

 in these processes of the subversion of disease, and the restoration of 

 health? Not to be tedious in enumerating instances, we may briefly 

 say, that the precise causation by which remedies cure diseases is 

 never known, or is latent, except in those instances where the cause 

 which produces disease is a sensible one, or in which we infer a 

 sensible cause from analogy. These exceptions belong most fre- 

 quently to that class of remedies which cure diseases by an inter- 

 mediate relation, examples of which are specified under that class. 

 Inflammation, as pneumonia, is diminished by agents which reduce 

 the action of the heart, and diminish the volume of the circulating 

 fluids: the means which produce these effects are blood-letting, 

 which is perhaps directly related with the action of the heart, and 

 this action mediately with the state of inflammation; purgatives, 

 which are related with the properties of the intestines, and again 

 mediately with the state of inflammation; to which may be added 

 such medicines as nitre, ipecacuanha, emetic tartar, squill, digitalis, 

 &c. These means do not remove a supernumerary, or supply a 



