THE ACTIVE FORCES OF LIVING ORGANISMS 33 



majority of bitters, alkaloids, and narcotics, the 

 primary effect of which is to diminish and not to 

 increase oxidation ; and it is clear that when under 

 their influence a variation in the vibrations of the 

 nerve-cells takes place the change or reaction would 

 not be in the direction of diminished oxidation and 

 greater contractility, but of increased oxidation and 

 greater expansion, going in some cases so far as ex- 

 treme laxness. It therefore becomes a question of 

 some moment whether the action and reaction of all 

 drugs should not be considered primarily from the 

 double point of view of their effect on the degree of 

 contraction and of oxidation of the tissues. In so 

 doing, however, it is essential to remember that the 

 reaction of a drug may be beneficial or the reverse, 

 but that in general it is more permanent and lasting 

 than the primary action. This is a fact which is the 

 more likely to be overlooked, since one is always 

 inclined to ascribe improvement after medicinal treat- 

 ment, especially in the case of many tonics, to the 

 action of the drug administered, whereas in reality it 

 is frequently due to the reaction of the system after 

 the drug has ceased to act. Nor is this, as at first 

 sight might appear, a matter of slight importance, for 

 it is evident that in the case of a patient, the vibra- 

 tions of whose nerve-cells tend habitually to the side 

 of excessive contraction and diminished oxidation, the 

 application of a tonic, which by reaction produces 

 these very effects, could only ultimately increase the 

 evil, whereas in cases of an opposite nature it might 



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